Journal articles: 'Radiographic subtraction'

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Ruttimann, U. E. "Computer-Based Reconstruction and Temporal Subtraction of Radiographs." Advances in Dental Research 1, no. 1 (1987): 72–79. http://dx.doi.org/10.1177/08959374870010011601.

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The most important physical parameter limiting the diagnostic performance achieved with radiographic images is the signal-to-noise ratio (SNR). In most dental applications, the normal anatomical structures contribute to a background pattern in the image that is limiting the SNR attainable. Hence, the projection direction of radiographs is a fundamental determinant of the SNR. The acquisition of a basis set of projection images obtained from a plurality of spatially registered sampling directions permits the reconstruction of any desired slice lying within a limited volume by tomosynthesis. Alternatively, the multi-projection strategy permits synthesis of any arbitrary radiographic image whose projection direction lies within the cone spanned by the basis projection directions. This feature can be used to synthesize a desired image at the proper projection angle required for meaningful subtraction from a previously obtained radiograph, and thus to suppress anatomy-related background variations.

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Ferreira, Rívea Inês, Francisco Haiter-Neto, Cínthia Pereira Machado Tabchoury, Guilherme Assumpção Neves de Paiva, and Frab Norberto Bóscolo. "Assessment of enamel demineralization using conventional, digital, and digitized radiography." Brazilian Oral Research 20, no. 2 (2006): 114–19. http://dx.doi.org/10.1590/s1806-83242006000200005.

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This experimental research aimed at evaluating the accuracy of enamel demineralization detection using conventional, digital, and digitized radiographs, as well as to compare radiographs and logarithmically contrast-enhanced subtraction images. Enamel subsurface demineralization was induced on one of the approximal surfaces of 49 sound third molars. Standardized radiographs of the teeth were taken prior to and after the demineralization phase with three digital systems - CygnusRay MPS®, DenOptix® and DIGORA® - and InSight® film. Three radiologists interpreted the pairs of conventional, digital, and digitized radiographs in two different occasions. Logarithmically contrast-enhanced subtraction images were examined by a fourth radiologist only once. Radiographic diagnosis was validated by cross-sectional microhardness profiling in the test areas of the approximal surfaces. Accuracy was estimated by Receiver Operating Characteristic (ROC) analysis. Chi-square test, at a significance level of 5%, was used to compare the areas under the ROC curves (Az) calculated for the different imaging modalities. Concerning the radiographs, the DenOptix® system (Az = 0.91) and conventional radiographs (Az = 0.90) presented the highest accuracy values compared with the other three radiographic modalities. However, logarithmically contrast-enhanced subtraction images (Az = 0.98) were significantly more accurate than conventional, digital, and digitized radiographs (p = 0.0000). It can be concluded that the DenOptix® system and conventional radiographs provide better performance for diagnosing enamel subsurface demineralization. Logarithmic subtraction significantly improves radiographic detection.

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Jeffcoat, M. K., and M. S. Reddy. "Digital Subtraction Radiography for Longitudinal Assessment of Peri-Implant Bone Change: Method and Validation." Advances in Dental Research 7, no. 2 (1993): 196–201. http://dx.doi.org/10.1177/08959374930070021101.

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The purpose of this paper is to present a digital subtraction technique for the assessment of peri-implant bone change over time in vivo. Digital subtraction radiography may be used to detect areas of bony change that have occurred between radiographic examinations, and image processing algorithms have been developed which can relate the magnitude of the change on the subtraction image to a reference wedge, thereby allowing calculation of the mass of the lesion. This manuscript will present two algorithms for the assessment of osseous change. The method was validated in monkeys by means of small bony chips placed intra-orally prior to the first radiograph. The chips were removed, a second radiograph taken, and the images subtracted. Each algorithm was used to isolate the lesion and calculate change in bone mass. Overall, there was excellent correlation between the calculated lesion mass (in milligrams) and actual lesion mass (r2 > 0.9). The utility of the method was demonstrated by comparison of the results of subtraction radiography in successful implants and in implants that did not integrate during the healing phase.

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Reddy, Michael S., and I.-Chung Wang. "Radiographic Determinants of Implant Performance." Advances in Dental Research 13, no. 1 (1999): 136–45. http://dx.doi.org/10.1177/08959374990130010301.

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This paper reviews and compares the strengths and weaknesses of radiographic techniques including periapical, occlusal, panoramic, direct digital, motion tomography, and computed tomography. Practical considerations for each method, including availability and accessibility, are discussed. To date, digital subtraction radiography is the most versatile and sensitive method for measuring boss loss. It can detect both bone height and bone mass changes on root-form or blade-form dental implants. Criteria for implant success have changed substantially over the past two decades. In clinical trials of dental implants, the outcomes require certain radiographic analyses to address the hypothesis or clinical question adequately. Radiographic methods best suited to the objective assessment of implant performance and hypothesis were reviewed.

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da Silva, Renan Lucio Berbel, Eduardo Felippe Duailibi Neto, Franscisco Fernando Todescan, Glaucio Morente Ruiz, Claudio Mendes Pannuti, and Israel Chilvarquer. "Evaluation of cervical peri-implant optical density in longitudinal control of immediate implants in the anterior maxilla region." Dentomaxillofacial Radiology 49, no. 6 (2020): 20190396. http://dx.doi.org/10.1259/dmfr.20190396.

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Objective: This research aimed to longitudinally evaluate the optical density of peri-implant alveolar bone. The data acquired from study participants previously treated with 37 osseointegrated implants were analyzed utilizing the radiographic subtraction technique. Methods and materials: The radiographic follow-ups were performed five times: at the implantation of the prostheses and after 15, 90, 180 and 360 days. Intraoral radiographs were obtained by the paralleling technique using individualized Hanshin-type positioners to guarantee the standardization of the images. The obtained digital images were aligned and equalized before they were submitted to the radiographic subtraction procedure. Results: A significant difference was found between the distal region of Group I (patients treated with osseointegrated implants who required extraction of the dental element) and the 360 day follow-up and the distal region of Group II (patients with healed alveolar sockets) in all follow-up analyses (p < 0.05). We did not observe a significant difference between the groups analyzed and other follow-ups concerning the subcrestal and middle third regions for both the mesial and distal variables (p > 0.05). There was a statistically significant difference in the distal sites [χ2 = 5,745,, p = 0.03], showing a significant association between time and the presence of bone resorption. This association was not shown on the mesial surface (p = 0.16). Conclusion: We concluded that there was no statistically significant difference between groups I and II. Using this technique, we were able to quantitatively and qualitatively evaluate the changes in the proximal sites on the digital radiographic images for the analyzed data. Digital subtraction technology to measure peri-implant bone density is an accurate and reproducible technique for quantifying peri-implant bone reactions to different therapeutic modalities.

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Van der Stelt, P. F. "Modern Radiographic Methods in the Diagnosis of Periodontal Disease." Advances in Dental Research 7, no. 2 (1993): 158–62. http://dx.doi.org/10.1177/08959374930070020601.

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For many years, radiographs have been a valuable aid in the diagnosis of periodontal disease and the evaluation of treatment effects. Computer-based image acquisition and processing techniques will now further increase the importance of radiography in periodontal diagnosis. Temporal changes of lesions can be made easily visible by means of subtraction radiography based on digital images. This process requires a pair of images with identical gray-level distributions and projection geometry. The gray-level distribution and perspective projection of images can be corrected by means of digital image processing. A pair of identical images can thus be obtained without mechanical alignment of patient, film, and x-ray source. Algorithms have been developed for automatical determination of the borders of lesions and can subsequently produce quantitative information ranging from simple distance measurements to advanced multidimensional quantitation of image parameters. Accurate volume measurements can be carried out by the utilization of calibration wedges in the image. Image reconstruction procedures, such as tomosynthesis, provide information about the third dimension, which is normally lost in conventional radiographic projections. The buccal and lingual sites of the alveolar crest can be inspected separately. The progress of computer-aided procedures as discussed in this paper appears to have great potential for the improvement of the radiographic diagnosis of periodontal lesions. Especially, the benefits of reproducibility and quantitative evaluation of treatment effects will greatly improve the role of radiography in periodontics.

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Wang, Michael Y., and Sigurd H. Berven. "Lumbar Pedicle Subtraction Osteotomy." Operative Neurosurgery 60, suppl_2 (2007): ONS—140—ONS—146. http://dx.doi.org/10.1227/01.neu.0000249240.35731.8f.

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Abstract THE CORRECTION OF lumbar kyphotic deformities requires careful preoperative clinical and radiographic evaluation. For patients with rigid deformities at locations where previous anterior spinal surgery was performed, pedicle subtraction osteotomy remains an attractive treatment option. This technique uses a single-stage posterior approach for removal of the posterior elements and a wedge of the vertebral body. Using this method, it is possible to introduce up to 35 degrees of lumbar lordosis and add up to 10 cm of posterior trunk translation. Patient satisfaction from correction of these deformities is frequently excellent, but a high degree of attention must be directed to avoid neural injuries and reduce intraoperative blood loss.

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De Lin, Ming, Ehsan Samei, Cristian T. Badea, Terry T. Yoshizumi, and G. Allan Johnson. "Optimized radiographic spectra for small animal digital subtraction angiography." Medical Physics 33, no. 11 (2006): 4249–57. http://dx.doi.org/10.1118/1.2356646.

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PARTRIDGE, J. B., and R. E. SLAUGHTER. "Radiographic Projections for Coronary Angiography – Implications for Digital Subtraction Angiography." Australasian Radiology 30, no. 3 (1986): 230–35. http://dx.doi.org/10.1111/j.1440-1673.1986.tb01745.x.

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Ricketts, D. N. J., K. R. Ekstrand, S. Martignon, R. Ellwood, M. Alatsaris, and Z. Nugent. "Accuracy and Reproducibility of Conventional Radiographic Assessment and Subtraction Radiography in Detecting Demineralization in Occlusal Surfaces." Caries Research 41, no. 2 (2007): 121–28. http://dx.doi.org/10.1159/000098045.

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Choi, Ho Yong, Seung-Jae Hyun, Ki-Jeong Kim, Tae-Ahn Jahng та Hyun-Jib Kim. "Surgical and Radiographic Outcomes After Pedicle Subtraction Osteotomy According to Surgeonʼs Experience". SPINE 42, № 13 (2017): E795—E801. http://dx.doi.org/10.1097/brs.0000000000001958.

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Singh, K., R. Sundgren, B. Bolstad, L. Björk, and M. Lie. "Iodixanol in Abdominal Digital Subtraction Angiography." Acta Radiologica 34, no. 3 (1993): 242–45. http://dx.doi.org/10.1177/028418519303400308.

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The safety, tolerability and efficacy of iodixanol 270 mg I/ml were compared to those of iohexol 300 mg I/ml in a double-blind, randomized, parallel abdominal intra-arterial DSA phase III trial. Fifty-nine patients were included in the trial; 39 patients received iodixanol and 20 received iohexol. The mean volume of iodixanol administered was 235.8 ml (0.93 g I/kg b.w.) while the mean volume of iohexol was 254.7 ml (1.10 g I/kg b.w.). No differences in diagnostic information and radiographic density were apparent in spite of the difference in the concentration of iodine. No serious adverse events occurred. Four patients (10%) in the iodixanol group and 2 (10%) in the iohexol group experienced adverse events. Eight percent of the injections of iodixanol promoted discomfort, compared to 12%) of the injections of iohexol. An increase in S-urea and S-creatinine was seen with both agents the first day after injection, but appeared to be less pronounced with iodixanol than with iohexol. Other serum tests revealed no changes of clinical importance. Both iodixanol and iohexol were found to be effective, safe and well tolerated contrast media for abdominal intra-arterial DSA.

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Ibrahim, Dalia, Ahmed El Fiki, Mohamed Hafez, and Sahar Saleem. "Report of a case of cavernous haemangioma of the cavernous sinus." BJR|case reports 5, no. 4 (2019): 20190031. http://dx.doi.org/10.1259/bjrcr.20190031.

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Cavernous haemangioma of the cavernous sinus is a rare vascular malformation. It's often confused with other parasellar masses. Here, we report a case of a female with a left parasellar mass which was misdiagnosed as schwannoma vs meningioma using CT and MRI. The patient was operated via the pterional approach but resection had been halted due to severe haemorrhage and only tumour biopsy could be obtained. The diagnosis of cavernous sinus haemangioma was established by histopathology and confirmed by subsequent digital subtraction angiography. The patient refused second surgery or adjuvant radiosurgery and the treatment strategy was observation and follow-up. Retrospectively, we included the key radiographic features of cavernous sinus haemangioma which would facilitate pre-operative diagnosis and avoid unforeseen operative complications. Diagnostic radiographic features include a well-defined mass in the cavernous sinus which shows isodense to slightly hyperdense attenuation on non-contrast CT scan with possible adjacent pressure bone remodelling. On MRI, it shows remarkable high T2 signal; intense homogenous enhancement or characteristic progressive contrast enhancement on sequential enhanced images. On digital subtraction angiography, it may demonstrate a vascular blush.

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Arslan, Soley, and Melek Hilal Kaplan. "The Effect of Resin Infiltration on the Progression of Proximal Caries Lesions: A Randomized Clinical Trial." Medical Principles and Practice 29, no. 3 (2019): 238–43. http://dx.doi.org/10.1159/000503053.

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Objective: The aim of this clinical trial was to assess the effect of resin infiltration on the progression of proximal caries lesions. Subjects and Methods: Forty-one patients, aged between 15 and 33 years, with 2 or more non-cavitated proximal caries lesions were included. In 41 of the adolescent and young adults, 45 pairs of proximal lesions with radiological extension into the inner and outer half of the enamel, or into the outer third of the dentin, were randomly allocated to the test groups (resin infiltration application + fluoridated toothpaste and flossing use) or to the control group (fluoridated toothpaste and flossing use). Standardized geometrically aligned digital bitewing radiographs were obtained using individual biting holders. The radiographic progression of the lesions was assessed after 1 year by digital-subtraction radiography. The McNemar test was used for statistical analysis. Results: In the test group 1/45 of the lesions (2.2%) and in the control group 9/45 of the lesions (20%) showed progression. The caries progression rate of the control group was significantly higher than that of the test group (p < 0.05). Conclusions: Resin infiltration of proximal caries lesions is effective in reducing progression of the lesion.

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Mirzapour, M., A. Movafeghi, and E. Yahaghi. "Quantitative weld defect sizing using convolutional neural network-aided processing of RT images." Insight - Non-Destructive Testing and Condition Monitoring 63, no. 3 (2021): 141–45. http://dx.doi.org/10.1784/insi.2021.63.3.141.

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Non-destructive confirmation of seamless welding is of critical importance in most applications and digital industrial radiography (DIR) is often the method of choice for internal flaw detection. DIR images often suffer from fogginess, limiting the inspection of flawed regions in online and quantitative applications. Much focus has therefore been put on denoising and image fog removal to yield better outcomes. One of the methods most widely used to improve the image is the fast and flexible denoising convolutional neural network (FFCN). This method has been shown to offer excellent image quality performance combined with fast execution and computing efficiency. In this study, the FFCN image processing technique is implemented and applied to radiographic images of welded objects. Enhancement of defect detection is achieved through sharpening of the image feature edges, leading to improved quantification in weld flaw sizing. The method is applied to the radiographic images using the weighted subtraction method. Experienced radiographers find that the weld defect detail is better visualised with output images from the FFCN algorithm compared to the original radiographs. Improvement in weld flaw size quantification is evaluated using test objects and the distance between the first two lines of the image quality indicator (IQI). The results show that the applied algorithm enhances the visualisation of internal defects and increases the detectability of fine fractures in the welded region. It is also found that, by selective image contrast enhancement near the flaw edges, flaw size quantification is improved significantly. The algorithm is found to be efficient, enabling online automated implementation on standard personal computers.

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Khalifehzadeh, Shabnam, Sina Haghanifar, Niloofar Jenabian, Sohrab Kazemi, and Mahmoud Hajiahmadi. "Clinical and radiographic evaluation of applying 1% metformin biofilm with plasma rich in growth factor (PRGF) for treatment of two-wall intrabony periodontal defects: A randomized clinical trial." Journal of Dental Research, Dental Clinics, Dental Prospects 13, no. 1 (2019): 51–56. http://dx.doi.org/10.15171/joddd.2019.008.

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Background. The ultimate aim of periodontal treatment is to regenerate periodontium and regenerative treatment after that. The aim of this study was to evaluate the effect of PRGF with 1% metformin biofilm in the treatment of two-wall intrabony periodontal defects. Methods. In this clinical trial, 8 patients with moderate chronic periodontitis and two-wall intrabony defect were selected. The defects were assigned to 4 groups: debridement, 1% metformin, PRGF, PRGF and metformin. The parameters of vertical probing depth, vertical clinical attachment level and gingival index were measured at baseline, immediately before surgery, and 3 and 6 months after surgery. In addition, the radiographic changes were evaluated with digital subtraction radiography before and 6 months after surgery. Analysis of the results was performed with repeated measurements, Friedman test and chisquared test. Results. All the groups exhibited improvements in all the clinical parameters after 6 months. Inter-group comparison of GI, CAL and PPD parameters revealed no statistically significant differences. Radiographic changes in the group of 1% metformin with PRGF revealed statistically significant differences compared with other groups; however, there were no statistically significant differences in other groups. Conclusion. Application of PRGF with 1% metformin in intrabony two-wall periodontal defects was effective in improving the clinical parameters but this effect revealed no difference compared with other groups; however, in terms of radiographic changes significant improvements were noted.

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Brian, O'Shaughnessy, Tim Kuklo, Benson Yang, Tyler Koski, and Stephen Ondra. "P68. Thoracic Pedicle Subtraction Osteotomy for Fixed Sagittal Deformity: Clinical and Radiographic Outcomes." Spine Journal 7, no. 5 (2007): 114S. http://dx.doi.org/10.1016/j.spinee.2007.07.274.

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Smith, Justin S., Christopher I. Shaffrey, Virginie Lafage, et al. "Spontaneous improvement of cervical alignment after correction of global sagittal balance following pedicle subtraction osteotomy." Journal of Neurosurgery: Spine 17, no. 4 (2012): 300–307. http://dx.doi.org/10.3171/2012.6.spine1250.

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Object Sagittal spinopelvic malalignment is a significant cause of pain and disability in patients with adult spinal deformity. Surgical correction of spinopelvic malalignment can result in compensatory changes in spinal alignment outside of the fused spinal segments. These compensatory changes, termed reciprocal changes, have been defined for thoracic and lumbar regions but not for the cervical spine. The object of this study was to evaluate postoperative reciprocal changes within the cervical spine following lumbar pedicle subtraction osteotomy (PSO). Methods This was a multicenter retrospective radiographic analysis of patients from International Spine Study Group centers. Inclusion criteria were as follows: adults (>18 years old) with spinal deformity treated using lumbar PSO, a preoperative C7–S1 plumb line greater than 5 cm, and availability of pre- and postoperative full-length standing radiographs. Results Seventy-five patients (60 women, mean age 59 years) were included. The lumbar PSO significantly improved sagittal alignment, including the C7–S1 plumb line, C7–T12 inclination, and pelvic tilt (p <0.001). After lumbar PSO, reciprocal changes were seen to occur in C2–7 cervical lordosis (from 30.8° to 21.6°, p <0.001), C2–7 plumb line (from 27.0 mm to 22.9 mm), and T-1 slope (from −38.9° to −30.4°, p <0.001). Ideal correction of sagittal malalignment (postoperative sagittal vertical alignment < 50 mm) was associated with the greatest relaxation of cervical hyperlordosis (−12.4° vs −5.7°, p = 0.037). A change in cervical lordosis correlated with changes in T-1 slope (r = −0.621, p <0.001), C7–T12 inclination (r = 0.418, p <0.001), T12–S1 angle (r = −0.339, p = 0.005), and C7–S1 plumb line (r = 0.289, p = 0.018). Radiographic parameters that correlated with changes in cervical lordosis on multivariate linear regression analysis included change in T-1 slope and change in C2–7 plumb line (r2 = 0.53, p <0.001). Conclusions Adults with positive sagittal spinopelvic malalignment compensate with abnormally increased cervical lordosis in an effort to maintain horizontal gaze. Surgical correction of sagittal malalignment results in improvement of the abnormal cervical hyperlordosis through reciprocal changes.

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Yang, Benson P., Stephen L. Ondra, Larry A. Chen, Hee Soo Jung, Tyler R. Koski, and Sean A. Salehi. "Clinical and radiographic outcomes of thoracic and lumbar pedicle subtraction osteotomy for fixed sagittal imbalance." Journal of Neurosurgery: Spine 5, no. 1 (2006): 9–17. http://dx.doi.org/10.3171/spi.2006.5.1.9.

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Object he authors conducted a study to evaluate the radiographically documented and functional outcomes obtained in patients who underwent pedicle subtraction osteotomy (PSO). They also compared outcomes after classification of cases into thoracic and lumbar PSO subgroups. Methods he authors analyzed data obtained in 35 consecutive PSO-treated patients with sagittal imbalance. One surgeon performed all surgeries. The minimal follow-up period was 2 years. Events during the perioperative course and complications were noted. Standing long-film radiographs of the spine were obtained and measurements were made preoperatively, immediately postoperatively, and at most recent follow-up examination. The modified Prolo Scale and the 22-item Scoliosis Research Society (SRS-22) Outcomes Questionnaire were administered. Early complications after PSO included neurological injury, wound-related problems, and nosocomial infections. Late complications were limited to pseudarthrosis and attendant instrumentation failure. Early and late complication rates ranged from 10 to 30% for both thoracic and lumbar PSO cohorts. Lumbar PSO was associated with improvements in local, segmental, and global measures of sagittal balance, whereas thoracic PSO was only associated with local improvement. Most patients rated their functional status as fair to good according to the modified Prolo Scale and reported, according to the SRS-22 Outcomes Questionnaire, that they were satisfied with the overall treatment of their back condition. Conclusions The ability to perform a PSO at both lumbar and thoracic levels is a powerful asset for the spine surgeon treating spinal deformity. In the present study radiographic and clinical outcomes were superior when PSO was used to treat lumbar deformity rather than thoracic deformity because of several anatomical and technical obstacles that hindered the thoracic procedure. Nevertheless, the thoracic PSO proved a useful addition with which to produce regional improvement in sagittal balance for patients with a fixed thoracic kyphosis.

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Choi, Ho Yong, Seung-Jae Hyun, Ki-Jeong Kim, Tae-Ahn Jahng, and Hyun-Jib Kim. "Radiographic and Clinical Outcomes Following Pedicle Subtraction Osteotomy : Minimum 2-Year Follow-Up Data." Journal of Korean Neurosurgical Society 63, no. 1 (2020): 99–107. http://dx.doi.org/10.3340/jkns.2018.0170.

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Cury, Patricia R., Ney S. Araujo, Jon Bowie, Enilson A. Sallum, and Marjorie K. Jeffcoat. "Comparison Between Subtraction Radiography and Conventional Radiographic Interpretation During Long-Term Evaluation of Periodontal Therapy in Class II Furcation Defects." Journal of Periodontology 75, no. 8 (2004): 1145–49. http://dx.doi.org/10.1902/jop.2004.75.8.1145.

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Lee, Keun-Ho, Ki-Tack Kim, Yong-Chan Kim, Joong-Won Lee, and Kee-Yong Ha. "Radiographic findings for surgery-related complications after pedicle subtraction osteotomy for thoracolumbar kyphosis in 230 patients with ankylosing spondylitis." Journal of Neurosurgery: Spine 33, no. 3 (2020): 366–72. http://dx.doi.org/10.3171/2020.3.spine191355.

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OBJECTIVEThe purpose of this study was to investigate the rate of and the risk factors for surgery-related complications demonstrated on radiography after pedicle subtraction osteotomy (PSO) for thoracolumbar kyphosis in patients with ankylosing spondylitis (AS).METHODSThe authors retrospectively reviewed the medical records of 230 consecutive patients with thoracolumbar kyphosis due to AS who had undergone 1-level PSO at a single institution in the period from 2010 to 2017. The causes of surgery-related complications were divided into two types: surgical/technical failure and mechanical failure.RESULTSThe patients consisted of 20 women and 210 men, with an average age of 43.4 years. The average follow-up period was 39.0 months. The preoperative sagittal vertical axis was 18.5 ± 69.3 cm, which improved to 4.9 ± 4.6 cm after PSO. Of the 77 patients (33.5%) who experienced minor or major surgery-related complications, 56 had complications related to surgical/technical failure (overall incidence 24.3%) and 21 had complications related to mechanical failure (overall incidence 9.1%). Fourteen patients (6.1%) underwent reoperation. However, among the 77 patients with complications, the rate of revision surgery was 18.2%. The most common radiological complications were as follows: sagittal translation in 24 patients, coronal imbalance in 20, under-correction in 8, delayed union in 8, and distal junctional failure and kyphosis in 8. The most common causes of reoperation were coronal imbalance in 4 patients, symptomatic malposition of pedicle screws in 3, and distal junctional failure in 3. Delayed union was statistically correlated with posterior sagittal translation (p = 0.007).CONCLUSIONSPSO can provide acceptable radiographic outcomes for the correction of thoracolumbar kyphosis in patients with AS. However, a high incidence of surgery-related complications related to mechanical failure and surgical technique can develop. Thorough radiographic investigation before and during surgery is needed to determine whether complete ossification occurs along the anterior and posterior longitudinal ligaments of the spine.

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Deviren, Vedat, Justin K. Scheer, and Christopher P. Ames. "Technique of cervicothoracic junction pedicle subtraction osteotomy for cervical sagittal imbalance: report of 11 cases." Journal of Neurosurgery: Spine 15, no. 2 (2011): 174–81. http://dx.doi.org/10.3171/2011.3.spine10536.

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Object Sagittal imbalance of the cervicothoracic spine often causes severe pain and loss of horizontal gaze. Historically, the Smith-Peterson osteotomy has been used to restore sagittal balance. Cervicothoracic junction pedicle subtraction osteotomy (PSO) offers more controlled closure and greater biomechanical stability but has been infrequently reported in the literature. This study details the cervicothoracic PSO technique in 11 cases and correlates clinical kyphosis (chin-brow to vertical angle [CBVA]) with radiographic measurements. Methods Between February 2008 and September 2010, 11 patients (mean age 70 years) underwent a modified PSO (10 at C-7, 1 at T-1) for treatment of sagittal imbalance. Preoperative and postoperative sagittal plane radiographic measurements were made. The CBVA was measured on clinical photographs. Operative technique and perioperative correction were reported for all 11 patients and long-term follow-up data was reported for 9 patients, in whom the mean duration of follow-up was 23 months. Outcome measures used for these 9 patients were the Neck Disability Index, the 36-Item Short Form Health Survey (SF-36), and a visual analog scale for neck pain. Results The mean values for estimated blood loss, surgical time, and hospital stay in the 11 patients were 1100 ml, 4.3 hours, and 9.9 days, respectively. The mean preoperative and immediate postoperative values (± SD) for cervical sagittal imbalance were 7.9 ± 1.4 cm and 3.4 ± 1.7 cm. The mean overall correction was 4.5 ± 1.5 cm (42.8%), the mean PSO correction 19.0°, and the mean CBVA correction 36.7°. There was essentially no correlation between preoperative C2–T1 radiographic kyphosis and preoperative CBVA (R2 = 0.0165). There was a moderate correlation with PSO correction angle and postoperative CBVA (R2 = 0.38). There was a significant decrease in both the Neck Disability Index (51.1 to 38.6, p = 0.03) and visual analog scale scores for neck pain (8.1 to 3.9, p = 0.0021). The SF-36 physical component summary scores increased by 18.4% (30.2 to 35.8) with no neurological complications. Conclusions The cervicothoracic junction PSO is a safe and effective procedure for the management of cervicothoracic kyphotic deformity. It results in excellent correction of cervical kyphosis and CBVA with a controlled closure and improvement in health-related quality-of-life measures even at early time points.

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Yu, Qian, Lifeng He, Tsuyoshi Nakamura, Yuyan Chao, and Kenji Suzuki. "A Mutual-Information-Based Global Matching Method for Chest-Radiography Temporal Subtraction." Journal of Advanced Computational Intelligence and Intelligent Informatics 16, no. 7 (2012): 841–50. http://dx.doi.org/10.20965/jaciii.2012.p0841.

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Lung cancer is the most common cancer in the world. Early detection is most important for reducing death due to lung cancer. Chest radiography has been widely and frequently used for the detection and diagnosis of lung cancer. To assess pathological changes in chest radiographs, radiologists often compare the previous chest radiograph and the current one from the same patient at different times. A temporal subtraction image, which is constructed from the previous and current radiographs, is often used to support this comparison work. This paper presents a Mutual-Information (MI)-based global matching method for chest-radiography temporal subtraction. We first make a preliminary transformation on the previous radiograph to make the center line of the lungs in the previous radiograph coincide with that of the current one. Then, we specify areas of the lungs to be used for mutual information registration and extract rib edges in these areas. We transform the rib edge image of the previous radiograph until mutual information between the rib edge image of the previous radiograph and that of the current radiograph becomes maximal. Finally, we use the same transform parameters to transform the previous radiograph, and then use the current radiograph and the transformed previous radiograph to construct the temporal subtraction image. The experimental result demonstrates that our proposed method can enhance pathological changes and reduces misregistration artifacts.

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Grondahl, K., B. Kullendorff, K. G. Strid, H. G. Grondahl, and C. O. Henrikson. "Detectability of artificial marginal bone lesions as a function of lesion depth. A comparison between subtraction radiography and conventional radiographic technique." Journal of Clinical Periodontology 15, no. 3 (1988): 156–62. http://dx.doi.org/10.1111/j.1600-051x.1988.tb01562.x.

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Lee, Ji-Young, Seung-Bum Kye, Won-Kyoung Kim, et al. "The Effect of Splinting with Concomitant Root Planing: A Clinical and Digital Subtraction Radiographic Study." Journal of the Korean Academy of Periodontology 31, no. 1 (2001): 207. http://dx.doi.org/10.5051/jkape.2001.31.1.207.

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Queiroz, Adriana C., Priscila Brasil da Nobrega, Fabiola S. Oliveira, et al. "Treatment of Intrabony Defects with Anorganic Bone Matrix/P-15 or Guided Tissue Regeneration in Patients with Aggressive Periodontitis." Brazilian Dental Journal 24, no. 3 (2013): 204–12. http://dx.doi.org/10.1590/0103-6440201302169.

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Intrabony periodontal defects present a particular treatment problem, especially in patients with generalized aggressive periodontitis (G-AgP). Regenerative procedures have been indicated for this clinical situation. The aim of this study was to compare treatment outcomes of intrabony periodontal defects with either anorganic bone matrix/cell binding peptide (ABM/P-15) or guided tissue regeneration (GTR) in patients with G-AgP. Fifteen patients, with two intrabony defects ≥3 mm deep, were selected. Patients were randomly allocated to be treated with ABM/P-15 or GTR. At baseline and at 3 and 6 months after surgery, clinical and radiographic parameters and IL-1β and IL-6 gingival fluid concentrations were recorded. There was a significant probing pocket depth reduction (p<0.001) for both groups (2.27 ± 0.96 mm for ABM/P-15 group and 2.57 ± 1.06 mm for GTR group). Clinical attachment level gain (1.87 ± 0.94 mm for ABM/P-15 group and 2.09 ± 0.88 mm for GTR group) was also observed. There were no statistically significant differences in clinical parameters between the groups. The radiographic bone fill was more expressive in ABM/P-15 group (2.49 mm) than in GTR group (0.73 mm). In subtraction radiographs, the areas representing gain in density were 93.16% of the baseline defect for ABM/P-15 group versus 62.03% in GRT group. There were no statistically significant differences in inter-group and intra-group comparisons with regards to IL-1β and IL-6 quantification. Treatment of intrabony periodontal defects in patients with G-AgP with ABM/P-15 and GTR improved significantly the clinical outcomes. The use of ABM/P-15 promoted a better radiographic bone fill.

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Cohen, A. M., A. D. Linney, and B. Reece. "Application of a Video Image Subtraction System to Measure and Control Head Position in Cephalometry." British Journal of Orthodontics 15, no. 2 (1988): 79–86. http://dx.doi.org/10.1179/bjo.15.2.79.

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Variation in head position in the cephalostat is a potential source of error in cephalometrics as it causes distortion of the radiographic projection of the head. Image subtraction is an electronic technique enabling images to be superimposed and which highlights any differences. Using this method, a study was carried out to assess the reproducibility of the position of the head in the cephalostat. It was also used to find out whether subjects could improve their own head relocation by looking at the monitor and trying to achieve the best possible fit on the original image.

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Ghuman, Mandeep, Vivek Gupta, Shankhneel Singh, S. Dhandapani, and N. Khandelwal. "Left Common Carotid Artery Agenesis with Hypoplastic Left Internal Carotid Artery Originating from the Aortic Arch: A Rare Anomaly Presenting with Internal Carotid Artery Aneurysm and Subarachnoid Hemorrhage." Journal of Clinical Interventional Radiology ISVIR 01, no. 01 (2017): 049–52. http://dx.doi.org/10.1055/s-0036-1597952.

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AbstractMost arch anomalies are asymptomatic and detected incidentally on imaging or on autopsy. Occasionally, such anomalies can manifest clinically when associated with another vascular pathology such as an intracranial aneurysm. In this report, we describe a rare case of agenesis of the left common carotid artery with separate origin of the left internal carotid artery and the external carotid artery from the arch discovered on digital subtraction angiography performed during the evaluation of subarachnoid hemorrhage. Knowledge of such anomalies and radiographic appearance is essential for interventional neuroradiologist in planning treatment of such cases.

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Schwab, Frank J., Ashish Patel, Christopher I. Shaffrey, et al. "Sagittal realignment failures following pedicle subtraction osteotomy surgery: are we doing enough?" Journal of Neurosurgery: Spine 16, no. 6 (2012): 539–46. http://dx.doi.org/10.3171/2012.2.spine11120.

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Object Pedicle subtraction osteotomy (PSO) is a surgical procedure that is frequently performed on patients with sagittal spinopelvic malalignment. Although it allows for substantial spinopelvic realignment, suboptimal realignment outcomes have been reported in up to 33% of patients. The authors' objective in the present study was to identify differences in radiographic profiles and surgical procedures between patients achieving successful versus failed spinopelvic realignment following PSO. Methods This study is a multicenter retrospective consecutive PSO case series. The authors evaluated 99 cases involving patients who underwent PSO for sagittal spinopelvic malalignment. Because precise cutoffs of acceptable residual postoperative sagittal vertical axis (SVA) values have not been well defined, comparisons were focused between patient groups with a postoperative SVA that could be clearly considered either a success or a failure. Only cases in which the patients had a postoperative SVA of less than 50 mm (successful PSO realignment) or more than 100 mm (failed PSO realignment) were included in the analysis. Radiographic measures and PSO parameters were compared between successful and failed PSO realignments. Results Seventy-nine patients met the inclusion criteria. Successful realignment was achieved in 61 patients (77%), while realignment failed in 18 (23%). Patients with failed realignment had larger preoperative SVA (mean 217.9 vs 106.7 mm, p < 0.01), larger pelvic tilt (mean 36.9° vs 30.7°, p < 0.01), larger pelvic incidence (mean 64.2° vs 53.7°, p < 0.01), and greater lumbar lordosis–pelvic incidence mismatch (−47.1° vs −30.9°, p < 0.01) compared with those in whom realignment was successful. Failed and successful realignments were similar regarding the vertebral level of the PSO, the median size of wedge resection 22.0° (interquartile range 16.5°−28.5°), and the numerical changes in pre- and postoperative spinopelvic parameters (p > 0.05). Conclusions Patients with failed PSO realignments had significantly larger preoperative spinopelvic deformity than patients in whom realignment was successful. Despite their apparent need for greater correction, the patients in the failed realignment group only received the same amount of correction as those in the successfully realigned patients. A single-level standard PSO may not achieve optimal outcome in patients with high preoperative spinopelvic sagittal malalignment. Patients with large spinopelvic deformities should receive larger osteotomies or additional corrective procedures beyond PSOs to avoid undercorrection.

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Eskilsson, Karin, Deep Sharma, Christer Johansson, and Rune Hedlund. "The impact of spinopelvic morphology on the short-term outcome of pedicle subtraction osteotomy in 104 patients." Journal of Neurosurgery: Spine 27, no. 1 (2017): 74–80. http://dx.doi.org/10.3171/2016.11.spine16601.

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OBJECTIVEPedicle subtraction osteotomy (PSO) is commonly performed for correction of spinal sagittal plane deformities. The PSO results in complex, multiple changes of the spinopelvic alignment. The influence of the variability of individual pelvic morphology has not been fully analyzed in previous outcome studies of sagittal imbalance. The aim of this study was to define radiological variables affecting the outcome after PSO in adult spinal deformities, with special emphasis on the variability of pelvic morphology.METHODSClinical and radiographic outcomes were analyzed in a retrospective analysis of 104 patients who underwent a PSO at a single center. The radiographic variables studied were sagittal vertical axis (SVA), T1SPI (T-1 spinopelvic inclination), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). To control for the individual variation of pelvic morphology, the LL/PI, PT/PI, and SS/PI ratios were calculated. Clinical outcome was assessed using the visual analog scale for pain, Oswestry Disability Index, and EQ-5D preoperatively and at a minimum 1-year follow-up. Correlation coefficients were calculated between each individual radiographic variable and the outcome measures. The importance of LL mismatch to TK, reflecting the importance of a harmonious spine, was analyzed by comparing the outcome of patients with a TK+LL+PI ≤ 45° to those with a sum > 45°.RESULTSSVA and T1SPI demonstrated the strongest correlation with the clinical outcome scores (r = 0.4–0.5, p < 0.001). LL correlated weakly with the clinical outcome (r = 0.2–0.3, p < 0.003). Mismatch of LL to PI, however, did not correlate significantly with the outcome. Similarly, only weak and inconsistent correlation was observed between PT, SS, PT/PI, SS/PI, and functional outcome. Patients with a TK+LL+PI ≤ 45° had a significantly lower ODI score (33 vs 44) and a significantly higher EQ-5D score (0.64 vs 0.40) than patients with a sum > 45° (LL is a negative value).CONCLUSIONSPSO resulted in a substantial correction of sagittal imbalance and improved outcome in most patients in this study. Correction of the global sagittal balance appears to be a necessary precondition for a good outcome. A harmonious spine with a TK and an LL of similar magnitude seems to add to a positive outcome.

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Okino, Taichi, Tamotsu Kamishima, Kenneth Lee Sutherland, et al. "Radiographic temporal subtraction analysis can detect finger joint space narrowing progression in rheumatoid arthritis with clinical low disease activity." Acta Radiologica 59, no. 4 (2017): 460–67. http://dx.doi.org/10.1177/0284185117721262.

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Background Recent papers suggest that finger joints with positive synovial vascularity (SV) assessed by ultrasonography under clinical low disease activity (CLDA) in rheumatoid arthritis (RA) patients may cause joint space narrowing (JSN) progression. Purpose To investigate the performance of a computer-based method by directly comparing with the conventional scoring method in terms of the detectability of JSN progression in hand radiography of RA patients with CLDA. Material and Methods Fifteen RA patients (13 women, 2 men) with long-term sustained CLDA of >2 years were included. Radiological progression of finger joints was measured or scored using the computer-based method which can detect JSN progression between two radiographic images as the joint space difference index (JSDI), as well as the Genant-modified Sharp score (GSS). We also quantitatively assessed SV of these joints using ultrasonography. Results Out of 270 joints, we targeted 259 finger joints after excluding nine damaged joints (four ankylosis, three complete luxation, and two subluxation) and two improved joints according to the GSS results. The JSDI of finger joints with JSN progression was significantly higher than those without JSN progression ( P = 0.018). The JSDI of finger joints with ultrasonographic SV was significantly higher than those without ultrasonographic SV ( P = 0.004). Progression in JSDI showed stronger associations with ultrasonographic SV than progression in GSS (odds ratio [95% confidence interval]: 7.19 [3.37–15.36] versus 5.84 [2.76–12.33]). Conclusion The computer-based method was comparable to the conventional scoring method regarding the detectability of JSN progression in RA patients with CLDA.

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Manwaring, Jotham C., Konrad Bach, Amir A. Ahmadian, Armen R. Deukmedjian, Donald A. Smith, and Juan S. Uribe. "Management of sagittal balance in adult spinal deformity with minimally invasive anterolateral lumbar interbody fusion: a preliminary radiographic study." Journal of Neurosurgery: Spine 20, no. 5 (2014): 515–22. http://dx.doi.org/10.3171/2014.2.spine1347.

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Object Minimally invasive (MI) fusion and instrumentation techniques are playing a new role in the treatment of adult spinal deformity. The open pedicle subtraction osteotomy (PSO) and Smith-Petersen osteotomy (SPO) are proven segmental methods for improving regional lordosis and global sagittal parameters. Recently the MI anterior column release (ACR) was introduced as a segmental method for treating sagittal imbalance. There is a paucity of data in the literature evaluating the alternatives to PSO and SPO for sagittal balance correction. Thus, the authors conducted a preliminary retrospective radiographic review of prospectively collected data from 2009 to 2012 at a single institution. The objectives of this study were to: 1) investigate the radiographic effect of MI-ACR on spinopelvic parameters, 2) compare the radiographic effect of MI-ACR with PSO and SPO for treatment of adult spinal deformity, and 3) investigate the radiographic effect of percutaneous posterior spinal instrumentation on spinopelvic parameters when combined with MI transpsoas lateral interbody fusion (LIF) for adult spinal deformity. Methods: Patient demographics and radiographic data were collected for 36 patients (9 patients who underwent MI-ACR and 27 patients who did not undergo MI-ACR). Patients included in the study were those who had undergone at least a 2-level MI-LIF procedure; adequate preoperative and postoperative 36-inch radiographs of the scoliotic curvature; a separate second-stage procedure for the placement of posterior spinal instrumentation; and a diagnosis of degenerative scoliosis (coronal Cobb angle > 10° and/or sagittal vertebral axis > 5 cm). Statistical analysis was performed for normality and significance testing. Results Percutaneous transpedicular spinal instrumentation did not significantly alter any of the spinopelvic parameters in either the ACR group or the non-ACR group. Lateral MI-LIF alone significantly improved coronal Cobb angle by 16°, and the fractional curve significantly improved in a subgroup treated with L5–S1 transforaminal lumbar interbody fusion. Fifteen ACRs were performed in 9 patients and resulted in significant coronal Cobb angle correction, lumbar lordosis correction of 16.5°, and sagittal vertebral axis correction of 4.8 cm per patient. Segmental analysis revealed a 12° gain in segmental lumbar lordosis and a 3.1-cm correction of the sagittal vertebral axis per ACR level treated. Conclusions The lateral MI-LIF with ACR has the ability to powerfully restore lumbar lordosis and correct sagittal imbalance. This segmental MI surgical technique boasts equivalence to SPO correction of these global radiographic parameters while simultaneously creating additional disc height and correcting coronal imbalance. Addition of posterior percutaneous instrumentation without in situ manipulation or overcorrection does not alter radiographic parameters when combined with the lateral MI-LIF.

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Miguens, Sergio Augusto Quevedo, Elaine Bauer Veeck, Vania Regina Camargo Fontanella, and Nilza Pereira da Costa. "A Comparison between Panoramic Digital and Digitized Images to Detect Simulated Periapical Lesions Using Radiographic Subtraction." Journal of Endodontics 34, no. 12 (2008): 1500–1503. http://dx.doi.org/10.1016/j.joen.2008.09.006.

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Anderson, Joshua L., Mohamed H. Khattab, Alexander D. Sherry, et al. "Improved Cerebral Arteriovenous Malformation Obliteration With 3-Dimensional Rotational Digital Subtraction Angiography for Radiosurgical Planning: A Retrospective Cohort Study." Neurosurgery 88, no. 1 (2020): 122–30. http://dx.doi.org/10.1093/neuros/nyaa321.

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Abstract BACKGROUND Stereotactic radiosurgery (SRS) for cerebral arteriovenous malformations (AVMs) is well-established. Radiographic advantages exist for 3-dimensional rotational digital subtraction angiography (3DRA) over 2-dimensional digital subtraction angiography (2D DSA) in delineating AVM nidus structure for SRS treatment planning. However, currently there is limited to no data directly comparing 2D DSA versus 3DRA in terms of patient outcomes. OBJECTIVE To investigate whether the use of 3DRA over 2D DSA in radiosurgical treatment planning for AVMs associates with improved clinical outcomes. METHODS All AVM patients treated with SRS at our institution between the years 2000 and 2018 were identified. Primary outcomes were obliteration rates and time to obliteration (TTO); secondary outcomes included rates of post-SRS hemorrhage, salvage therapy, and symptomatic radionecrosis. A minimum of 12 mo of follow-up imaging/angiogram post-SRS was required, or alternatively evidence of obliteration on angiogram prior to 12 mo post-SRS. Single predictor and multivariable Cox regression and logistic regression models were constructed to test for association between radiographic, clinical, and treatment factors with outcomes. RESULTS A total of 75 patients were included. Total 17 patients received 3DRA and 58 patients received 2D DSA, with a median follow-up of 3.29 yr. The 3DRA is significantly associated with improved TTO on single predictor (HR 2.87, 1.29-6.12; P = .0109) and multivariable analysis (HR 2.448, 1.076-5.750; P = .0330) and increased odds of achieving obliteration by 3 yr post-SRS on single predictor analysis (OR 6.044, 1.405-26.009; P = .0157). CONCLUSION The 3DRA over 2D DSA in SRS treatment planning for AVMs may result in improved TTO and 3-yr obliteration rates. Further investigation and prospective study are warranted.

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Saville, Philip A., Abhijeet B. Kadam, Harvey E. Smith, and Vincent Arlet. "Anterior hyperlordotic cages: early experience and radiographic results." Journal of Neurosurgery: Spine 25, no. 6 (2016): 713–19. http://dx.doi.org/10.3171/2016.4.spine151206.

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OBJECTIVE The aim of this study was to evaluate the segmental correction obtained from 20° and 30° hyperlordotic cages (HLCs) used for anterior lumbar interbody fusion in staged anterior and posterior fusion in adults with degenerative spinal pathology and/or spinal deformities. METHODS The authors report a retrospective case series of 69 HLCs in 41 patients with adult degenerative spine disease and/or deformities who underwent staged anterior, followed by posterior, instrumentation and fusion. There were 29 females and 12 males with a mean age of 55 years (range 23–76 years). The average follow-up was 10 months (range 2–28 months). Radiographic measurements of segmental lordosis and standard sagittal parameters were obtained on pre- and postoperative radiographs. Implant subsidence was measured at the final postoperative follow-up. RESULTS For 30° HLCs, the mean segmental lordosis achieved was 29° (range 26°–34°), but in the presence of spondylolisthesis this was reduced to 19° (range 12°–21°) (p < 0.01). For 20° HLCs, the mean segmental lordosis achieved was 19° (range 16°–22°). The overall mean lumbar lordosis increased from 39° to 59° (p < 0.01). The mean sagittal vertical axis (SVA) reduced from 113 mm (range 38–320 mm) to 43 mm (range −13 to 112 mm). Six cages (9%) displayed a loss of segmental lordosis during follow-up. The mean loss of segmental lordosis was 4.5° (range 3°–10°). A total complication rate of 20% with a 4.1% transient neurological complication rate was observed. The mean blood loss per patient was 240 ml (range 50–900 ml). CONCLUSIONS HLCs provide a reliable and stable degree of segmental lordosis correction. A 30° HLC will produce correction of a similar magnitude to a pedicle subtraction osteotomy, but with a lower complication rate and less blood loss.

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Ichikawa, Shota, Tamotsu Kamishima, Kenneth Sutherland, Takanobu Okubo, and Kou Katayama. "Radiographic quantifications of joint space narrowing progression by computer-based approach using temporal subtraction in rheumatoid wrist." British Journal of Radiology 89, no. 1057 (2016): 20150403. http://dx.doi.org/10.1259/bjr.20150403.

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Gkanatsios, Nikolaos A., Walter Huda, and Keith R. Peters. "Effect of radiographic techniques (kVp and mAs) on image quality and patient doses in digital subtraction angiography." Medical Physics 29, no. 8 (2002): 1643–50. http://dx.doi.org/10.1118/1.1493213.

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Seifalian, A. M., D. J. Hawkes, C. R. Hardingham, A. C. F. Colchester, and J. F. Reidy. "Validation of a quantitative radiographic technique to estimate pulsatile blood flow waveforms using digital subtraction angiographic data." Journal of Biomedical Engineering 13, no. 3 (1991): 225–33. http://dx.doi.org/10.1016/0141-5425(91)90132-q.

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Bundit, Arpapan, Pusadee Yotnuengnit, Sirinun Wisetsin, and Apichart Chittacharoen. "A Randomized Controlled Trial and Radiographic Evaluation of Adjunctive Periodontal Treatment with Calcium and Vitamin D Supplementation." International Journal of Experimental Dental Science 5, no. 1 (2016): 50–55. http://dx.doi.org/10.5005/jp-journals-10029-1123.

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ABSTRACT Aim The objective of this study was to use clinical parameters, digital subtraction analysis, and computer intensity measurement to evaluate the effect of calcium and vitamin D supplementation in adult periodontitis patients with vertical bony defect after initial therapy. Materials and methods A total of 31 systemically healthy patients with moderate to severe chronic periodontitis and normal serum calcium level were included. The most obvious proximal vertical bony defect was selected in each patient as an area of interest (AOI). Subjects received initial periodontal therapy. They were randomized into two groups. The test group (n= 17) received calcium (600 mg twice daily) and vitamin D (0.25 µg once daily) supplements for 6 months. The control group (n= 14) received placebos. At baseline and 6 months, probing pocket depth (PPD), clinical attachment level (CAL), and standardized vertical bitewing radiographs were recorded for the AOI. Results A greater percentage of patients in the test group (64.7%) than in the control group (35.7%) gained bone according to both radiographic evaluation methods. At baseline and 6 months, no significant intragroup or intergroup differences in PPD and CAL were observed. Slightly greater PPD reduction and CAL gain were noted in the test group. Conclusion Periodontal healing of vertical bony defects was better among patients who used calcium and vitamin D supplements than among control patients. Although the difference was not statistically different between the groups, the test group tended toward more improvement. How to cite this article Bundit A, Yotnuengnit P, Wisetsin S, Chittacharoen A. A Randomized Controlled Trial and Radiographic Evaluation of Adjunctive Periodontal Treatment with Calcium and Vitamin D Supplementation. Int J Experiment Dent Sci 2016;5(1):50-55.

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Rutkowski, James L., David A. Johnson, Nicholas M. Radio, and James W. Fennell. "Platelet Rich Plasma to Facilitate Wound Healing Following Tooth Extraction." Journal of Oral Implantology 36, no. 1 (2010): 11–23. http://dx.doi.org/10.1563/aaid-joi-09-00063.

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Abstract Following tooth removal bone formation normally takes 16 weeks and may result in less than adequate volume for the necessary reconstruction. Platelet rich plasma (PRP) has been promoted as an effective method for improving bone formation. Its use is often expensive, time consuming, or not clinically convenient for the patient and/or clinician. This study examines a simple method for obtaining a “Buffy Coat”-PRP (BC-PRP) and its effect on bone healing following the removal of bilateral mandibular 3rd molars. Subtraction digital radiography and CT scan analysis were used to track changes in radiographic density at PRP treated sites in comparison to ipsilateral non-PRP treated sites. PRP treated sites demonstrated early and significant increased radiographic density over baseline measurements following tooth removal. The greatest benefit of PRP is during the initial 2-week postoperative healing time period (P &lt; .001). During weeks 3 though 12, BC-PRP treatment resulted in significant (P &lt; .0001) increases in bone density compared to control, but there was no significant interaction between time and treatment (P &gt; .05). For the entire time period (0–25 weeks) PRP treatment was significant (P &lt; .0001) and time was significant (P &lt; .0001) but there was no significant interaction (P &gt; .05) between the effect of PRP treatment and time. It required 6 weeks for control extraction sites to reach comparable bone density that PRP treated sites achieved at week 1. Postoperative pain, bleeding, and numbness were not significantly affected by BC-PRP application. Results suggest that this simple technique may be of value to clinicians performing oral surgery by facilitating bone regeneration following tooth extraction.

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Zeng, Yan, Zhongqiang Chen, Qiang Qi, et al. "Clinical and radiographic evaluation of posterior surgical correction for the treatment of moderate to severe post-tuberculosis kyphosis in 36 cases with a minimum 2-year follow-up." Journal of Neurosurgery: Spine 16, no. 4 (2012): 351–58. http://dx.doi.org/10.3171/2011.12.spine11568.

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Object The object of this study was to compare the clinical and radiographic outcomes of 36 patients with posttuberculosis kyphosis who underwent one of two types of osteotomy. Methods Each patient underwent single-stage correction via a posterior surgical approach. A modified pedicle subtraction osteotomy (mPSO) was performed when the kyphotic deformity was less than 70° (7 cases), whereas a posterior vertebral column resection (VCR) was performed when the kyphotic deformity exceeded 70° (29 cases). Full-length standing radiographs were obtained before surgery and at follow-up visits. These images were used to measure the kyphosis angle; sagittal alignment of the lumbar, thoracic, and cervical regions; and sagittal balance of the spine. Back pain was rated using the visual analog scale (VAS), and neurological function was classified based on the American Spinal Injury Association (ASIA) grading system. Each patient's overall satisfaction with surgical treatment was measured with the Patient Satisfaction Index. For purposes of comparison, patients were studied in 2 groups based on the region of their kyphotic apex. Half of the cohort had apical kyphosis in the lower thoracic spine or thoracolumbar junction (TL group). Using both radiographic and clinical assessments, the authors compared this group with the other half of the patients who had apical kyphosis in the upper to mid thoracic spine (MT group). Results The cohort included 15 males and 21 females, with an average age of 34 years at the time of surgery. The minimum follow-up was 24 months, and the mean follow-up was 31 months. Following surgery, kyphosis across the treated segments was reduced by an average of 60°. Lumbar lordosis also improved by an average of 24°, and thoracic kyphosis improved by an average of 20°. Both back pain and neurological function improved after surgical treatment. There was a 67% improvement in VAS scores, and 13 of the 36 patients had improvement in their ASIA grade. The 2 surgical procedures used for deformity correction (mPSO and VCR) demonstrated comparable radiographic and clinical results. Note, however, that differences were found in both radiographic and clinical outcomes in comparing patients who had lower thoracic or thoracolumbar (TL group) versus upper to midthoracic (MT group) apical kyphosis. Conclusions Posterior tubercular kyphosis can be effectively improved through corrective surgery, and deformity correction can be accompanied by improvement in clinical symptoms. When appropriately selected, both the mPSO and the VCR can be expected to yield satisfactory reduction of post-tuberculosis kyphotic deformities. Differences in radiographic and clinical outcomes should be anticipated, however, when treating such deformities in different regions of the spine.

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Lopes, Demetrius Klee, Andrew Kelly Johnson, Robert Givens Kellogg, Daniel Mark Heiferman, and Kiffon Marie Keigher. "Long-term Radiographic Results of Stent-Assisted Embolization of Cerebral Aneurysms." Neurosurgery 74, no. 3 (2013): 286–91. http://dx.doi.org/10.1227/neu.0000000000000263.

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Abstract BACKGROUND: Aneurysmal subarachnoid hemorrhage is a disabling disease. Endovascular coiling provides minimally invasive, effective, and safe treatment of both ruptured and unruptured intracranial aneurysms. Intracranial stents have improved the endovascular treatment of complex aneurysms, but the long-term durability of this treatment modality needs clarification. OBJECTIVE: To elucidate the long-term success of intracranial stent use in the treatment of aneurysms. METHODS: Four hundred ten patients were treated with stent-assisted endovascular management of 464 aneurysms. Treatment of 363 small aneurysms, 88 large aneurysms, and 13 giant aneurysms was analyzed with respect to both long-term anatomic results with digital subtraction angiography and magnetic resonance angiography over the follow-up period. RESULTS: The 6-month angiographic results of 387 aneurysm treatments revealed complete aneurysm occlusion in 282 (72.9%), residual aneurysm neck in 50 (12.9%), and residual aneurysm filling in 55 (14.2%). Long-term radiographic follow-up, performed in 262 patients (mean, 3.63 years), showed significant recurrence of only 3 aneurysms after 6-month follow-up imaging. Forty-eight aneurysms (11.9%) were considered radiographic failures during the follow-up period. CONCLUSION: The aneurysm recurrence rate after stent-assisted embolization in this series was similar to published data using only coil embolization for the period between treatment and the initial follow-up imaging. For aneurysms that do not initially recur, the presented data suggest improved durability in the subsequent long-term follow-up period.

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Leveque, Jean-Christophe, Alicia Edwards, and Rajiv K. Sethi. "Preoperative, Intraoperative, and Postoperative Standing Lordosis After Pedicle Subtraction Osteotomy: An Analysis of Radiographic Parameters and Surgical Strategy." Spine Deformity 4, no. 3 (2016): 245–50. http://dx.doi.org/10.1016/j.jspd.2015.10.005.

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Muhtadan. "The utilization of image subtraction and wavelet decomposition-reconstruction for improving FCM based segmentation of radiographic weld defect." Journal of Innovative Technology and Education 3 (2016): 265–73. http://dx.doi.org/10.12988/jite.2016.61044.

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Queiroz, Christiano Sampaio, Viviane Almeida Sarmento, Roberto Almeida de Azevedo, Thaís Feitosa Leitão de Oliveira, and Luana Costa Bastos. "A comparative study of internal fixation and intermaxillary fixation on bone repair of mandibular fractures through radiographic subtraction." Journal of Cranio-Maxillofacial Surgery 42, no. 5 (2014): e152-e156. http://dx.doi.org/10.1016/j.jcms.2013.07.013.

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Panteleyev, A. A., S. P. Mironov, K. M. Buhtin та ін. "ЕFFECTIVENESS OF FOUR-ROD FIXATION FOR PEDICLE SUBTRACTION SPINAL OSTEOTOMY". Traumatology and Orthopedics of Russia 24, № 3 (2018): 65–73. http://dx.doi.org/10.21823/2311-2905-2018-24-3-65-73.

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Introduction.Pedicle subtraction osteotomy (PSO) provides for significant segmental correction of the sagittalbalance of the spine. At the same time, the technique is associated with a high risk of complications, with rod fracture at the osteotomy site being the most common. The purposeof this study — to assess the effectiveness of four-rod fixation compared to literature data on standardtwo-rod fixation in patients undergoing PSO. Materials and Methods.The study is a retrospective analysis of 47 consecutive patients with rigid spinaldeformities, who underwent pedicle subtraction osteotomy at the lumbar level. The average age of the patients (33 females and 14 males) was 59.7 years. In all cases spinal fixation carried out using a four-rod construct with additional short rods at the osteotomy site. The minimal postoperative follow-up was 2 years. A detailed analysis of the radiographic data was carried out with calculation of the global sagittal balance and spinopelvic parameters. A detailed assessment of complications in the early and late postoperative periods was also performed. After an exhaustive review of literature, a comparative analysis was made of the four-rod fixation technique with current literature data on the frequency of complications (in particular, rod fractures in the osteotomy zone) after two-rod fixation. Results.In all cases the osteotomy was performed at one level, most often at L3 (49%). The average length offixation was 9.8 segments. The average angle of segmental correction was 27.1°. In most cases, it was possible to achieve adequate correction of spinopelvic parameters. Among complications, bone resorption around screws was most prevalent (23.4% of cases). Proximal junctional kyphosis occurred in 12.8% of cases, neurologic deficit — in 14.9% of cases, infectious complications — in 10.6% cases. Asymptomatic pseudarthrosis, confirmed by CT data, was observed in 12.8% of patients. Rod fracture at the PSO site and adjacent segments was not observed in any of the cases. Rod fractures of other localization were observed in 10.6% of patients. Conclusion. According to the literature, the frequency of rod fractures at the osteotomy site is the most frequentcomplication of PSO. The results of this study showed that four-rod fixation in PSO significantly reduces the incidence of pseudarthrosis and rod fracture rate in the long-term follow-up and provides greater control over the process of osteotomy closure.

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Vasconcelos, Karla de Faria, Sergio Lins de-Azevedo-Vaz, Deborah Queiroz Freitas, and Francisco Haiter-Neto. "CBCT Post-Processing Tools to Manage the Progression of Invasive Cervical Resorption: A Case Report." Brazilian Dental Journal 27, no. 4 (2016): 476–80. http://dx.doi.org/10.1590/0103-6440201600740.

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Abstract This case report aimed to highlight the usefulness of cone beam computed tomography (CBCT) and its post-processing tools for the diagnosis, follow-up and treatment planning of invasive cervical resorption (ICR). A 16-year-old female patient was referred for periapical radiographic examination, which revealed an irregular but well demarcated radiolucency in the mandibular right central incisor. In addition, CBCT scanning was performed to distinguish between ICR and internal root resorption. After the diagnosis of ICR, the patient was advised to return shortly but did so only six years later. At that time, another CBCT scan was performed and CBCT registration and subtraction were done to document lesion progress. These imaging tools were able to show lesion progress and extent clearly and were fundamental for differential diagnosis and treatment decision.

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Hsu, Brian, Serkan Erkan, Ensor Transfeldt, et al. "194. Pedicle Subtraction vs. Smith-Petersen Osteotomies for Correction of Fixed Sagittal Plane Deformities: Radiographic Outcomes in 151 Patients." Spine Journal 8, no. 5 (2008): 97S. http://dx.doi.org/10.1016/j.spinee.2008.06.232.

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Kakizawa, Yukinari, Hisashi Nagashima, Fusakazu Oya, et al. "Compartments in arteriovenous malformation nidi demonstrated with rotational three-dimensional digital subtraction angiography by using selective microcatheterization." Journal of Neurosurgery 96, no. 4 (2002): 770–74. http://dx.doi.org/10.3171/jns.2002.96.4.0770.

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✓ Although in several histological studies of arteriovenous malformation (AVM) nidi the presence of compartments has been documented, no clinical study has been published. The present study was conducted to determine the presence of nidus compartments in clinical cases by using a new radiographic method. Two patients with unruptured and one with a ruptured AVM (all Spetzler—Martin Grade III) were studied. A microcatheter was superselectively introduced into each of two or three feeding arteries of the AVMs under three-dimensional (3D) angiographic guidance to obtain 3D images of the nidus by using rotational digital subtraction angiography. On 3D images the different feeding arteries were found to be independent from one another, which allowed the authors to confirm the presence of compartments. On the other hand, separate feeding arteries often had a common draining vessel. Compartments in AVM nidi were demonstrated by a novel rotational 3D angiographic procedure by using superselective microcatheterization, which should be useful for designing treatment strategies for large and complex AVMs.

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Journal articles on the topic 'Radiographic subtraction'

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