Academic literature on the topic 'Whole-brain map'

ObjectiveTo test the hypothesis that in periventricular nodular heterotopia (PVNH) structure and function of cortical areas overlying the heterotopic gray matter are preferentially affected.MethodsWe studied a group of 40 patients with PVNH and normal-appearing cortex and compared their quantitative MRI markers of brain development, structure, and function to those of 43 age- and sex-matched healthy controls. Inspired by models of neocortical development suggesting that neuronal migration follows a curvilinear path to preserve topologic correspondence between the outer ventricular zone and the cortical surface, we computationally defined the overlying cortex using the Laplace equation and generated synthetic streamlines that link the ventricles, where nodules are located, and the neocortex.ResultsWe found multilobar cortical thickening encompassing prefrontal, latero-basal temporal, and temporoparietal cortices largely corresponding with the PVNH group-averaged map of the overlying cortex, the latter colocalized with areas of abnormal function, as defined by resting-state fMRI. Patients also presented hippocampal functional hyperconnectivity and malrotation, the latter positively correlating with neocortical maldevelopment indexed by increased folding complexity of the parahippocampus. In clusters of thickness and curvature findings, there were no significant differences between unilateral and bilateral PVNH; contrasting brain-wide metrics between cohorts was also unrevealing. There was no relationship between imaging markers and disease duration except for positive correlation with functional anomalies.ConclusionOur quantitative image analysis demonstrates widespread structural and functional alterations in PVNH with differential interaction with the overlying cortex and the hippocampus. Right hemispheric predominance may be explained by an early insult, likely genetically determined, on brain morphogenesis.

This study was aimed at investigating the application of deep learning 4D computed tomography angiography (CTA) combined with whole brain CT perfusion (CTP) imaging in acute ischemic stroke (AIS). A total of 46 patients with ischemic stroke were selected from the hospital as the research objects. Image quality was analyzed after the 4D CTA images were obtained by perfusion imaging. The results showed that whole brain perfusion imaging based on FCN can achieve automatic segmentation. FCN segmentation results took a short time, an average of 2-3 seconds, and the Dice similarity coefficient (DSC) and mean absolute distance (MAD) were lower than those of other algorithms. FCN segmentation distance was 17.87. The parameters of the central area, the peripheral area, and the mirror area of the perfusion map were compared, and the mean transit time (MTT) and time to peak (TTP) of the lesion were prolonged compared with the mirror area. Moreover, the peripheral CBV was increased, and the differences between the parameters were significant ( P < 0.05 ). In conclusion, using the deep learning FCN network, 4D CTA combined with whole brain CTP imaging technology can effectively analyze the perfusion state and achieve clinically personalized treatment.

NeuroLF is a dedicated brain PET system with an octagonal prism shape housed in a scanner head that can be positioned around a patient’s head. Because it does not have MR or CT capabilities, attenuation correction based on an estimation of the attenuation map is a crucial feature. In this article, we demonstrate this method on [18F]FDG PET brain scans performed with a low-resolution proof of concept prototype of NeuroLF called BPET. We perform an affine registration of a template PET scan to the uncorrected emission image, and then apply the resulting transform to the corresponding template attenuation map. Using a whole-body PET/CT system as reference, we quantitively show that this method yields comparable image quality (0.893 average correlation to reference scan) to using the reference µ-map as obtained from the CT scan of the imaged patient (0.908 average correlation). We conclude from this initial study that attenuation correction using template registration instead of a patient CT delivers similar results and is an option for patients undergoing brain PET.

In neonatal rodents, a loss of brain stem serotonin [5-hydroxytryptamine (5-HT)] in utero or at birth compromises anoxia-induced gasping and the recovery of heart rate (HR) and breathing with reoxygenation (i.e., autoresuscitation). How mean arterial pressure (MAP) is influenced after an acute loss of brain stem 5-HT content is unknown. We hypothesized that a loss of 5-HT for ∼1 day would compromise MAP during episodic anoxia. We injected 6-fluorotryptophan (20 mg/kg ip) into rat pups (postnatal days 9–10 or 11–13, n = 22 treated, 24 control), causing a ∼70% loss of brain stem 5-HT. Pups were exposed to a maximum of 15 anoxic episodes, separated by 5 min of room air to allow autoresuscitation. In younger pups, we measured breathing frequency and tidal volume using “head-out” plethysmography and HR from the electrocardiogram. In older pups, we used whole body plethysmography to detect gasping, while monitoring MAP. Gasp latency and the time required for respiratory, HR, and MAP recovery following each episode were determined. Despite normal gasp latency, breathing frequency and a larger tidal volume ( P < 0.001), 5-HT-deficient pups survived one-half the number of episodes as controls ( P < 0.001). The anoxia-induced decrease in MAP experienced by 5-HT-deficient pups was double that of controls ( P = 0.017), despite the same drop in HR ( P = 0.48). MAP recovery was delayed ∼10 s by 5-HT deficiency ( P = 0.001). Our data suggest a loss of brain stem 5-HT leads to a pronounced, premature loss of MAP in response to episodic anoxia. These data may help explain why some sudden infant death syndrome cases die from what appears to be cardiovascular collapse during apparent severe hypoxia.