Changes in the Shape and Volume of Subcortical Structures in Patients With End-Stage Renal Disease

Introduction: End-stage renal disease (ESRD) typically causes changes in brain structure, and patients with ESRD often experience cognitive and sleep disorders. We aimed to assess the changes in the subcortical structure of patients with ESRD and how they are associated with cognitive and sleep disorders.Methods: We involved 36 adult patients for maintenance hemodialysis and 35 age- and gender-matched control individuals. All participants underwent neuropsychological examination and 3T magnetic resonance imaging (MRI) to acquire T1 anatomical images. The laboratory blood tests were performed in all patients with ESRD close to the time of the MR examination. We used volumetric and vertex-wise shape analysis approaches to investigate the volumes of 14 subcortical structural (e.g., bilateral accumbens, amygdala, hippocampus, caudate, globus pallidus, putamen, and thalamus) abnormalities in the two groups. Analyses of partial correlations and shape correlations were performed in order to identify the associations between subcortical structure, cognition, and sleep quality in patients with ESRD.Results: The volumetric analysis showed that compared with the healthy control group, patients with ESRD had less bilateral thalamus (left: p < 0.001; right: p < 0.001), bilateral accumbens (left: p < 0.001; right: p = 0.001), and right amygdala (p = 0.002) volumes. In the vertex-wise shape analysis, patients with ESRD had abnormal regional surface atrophy in the bilateral thalamus, right accumbens, left putamen, and bilateral caudate. Moreover, the Montreal Cognitive Assessment (MoCA) score was associated with volume reduction in the bilateral thalamus (left: Spearman ρ = 0.427, p = 0.009; right: ρ = 0.319, p = 0.018), and the Pittsburgh Sleep Quality Index (PSQI) score was associated with volume reduction in the bilateral accumbens (left: ρ = −0.546, p = 0.001; right: ρ = −0.544, p = 0.001). In vertex-wise shape correlation analysis, there was a positive significant correlation between regional shape deformations on the bilateral thalamus and MoCA score in patients with ESRD.Conclusion: Our study suggested that patients with ESRD have subcortical structural atrophy, which is related to impaired cognitive performance and sleep disturbances. These findings may help to further understand the underlying neural mechanisms of brain changes in patients with ESRD.

Bilateral thalamus stroke due to percheron artery

Bilateral thalamus ischemic stroke is a rare condition that carries significant morbidity and mortality in comparison to other forms of stroke. It is usually associated with an anatomical variant with the thalamic paramedian arteries arising from a common trunk from the posterior cerebellar artery, known as Percheron artery. This infarct is difficult to be recognized and early recognition of this syndrome improves survival and functional recovery. We report a case of bilateral thalamic stroke after cardiac surgery.

Artery of Percheron Occlusion: A Diagnostic Challenge

Artery of Percheron occlusion is a rare cause of ischaemic stroke characterized by bilateral thalamus infarction. Presentation is varied and non-specific, with the most frequent manifestations being altered level of consciousness, hypersomnolence or altered oculomotor movements. We describe the case of a 37-year-old man hospitalized for hypersomnia and hypomnesia with 3 days of evolution, who was diagnosed with a bilateral thalamus stroke due to artery of Percheron occlusion.

Abstract 1122‐000055: Parenchymal and Subarachnoid Angiogenesis in Patients with Vein of Galen Aneurysmal Malformation

Introduction : Vein of Galen Aneurysmal Malformation (VGAM) is an arteriovenous malformation that accounts for 30% of all pediatric vascular malformations. VGAMs undergo significant remodeling of hemodynamic and structural anatomy due to angiogenesis. These changes not only affect the malformation on a molecular and morphological basis, but may also lead to alterations in planned surgical procedures. It is imperative to better understand the dynamic, angiogenic environment of the cerebrovasculature in order to more effectively treat this disease. Methods : We present 36 cases of secondary angiogenesis in VGAM. We also present three case reports of angiogenesis secondary to VGAM. Results : Pre‐interventional angiogenesis was identified in 16 patients (44.4%) and post‐interventional angiogenesis in 20 patients (55.6%) following a stage of embolization therapy. The cohort of patients with pre‐interventional secondary angiogenesis was significantly older than patients with post‐interventional angiogenesis at initial angiogram (12 months ± 40.1 months vs. 4.0 months ± 5.4 months; p<0.05). Choroidal VGAMs presented with angiogenesis more frequently than Mural VGAMs (4/14 Mural vs 32/42 Choroidal; p<0.01). Angiogenesis was localized to either the left, right, or bilateral thalamus in 2 cases, to the cisternal space surrounding the VOG in 16 cases, and both in 18 cases. Conclusions : Upon identification of secondary angiogenesis, our team’s strategy is to embolize the venous component of the fistula. The ideal strategy in our practice is cannulation of the primary feeder of the malformation, as close to the fistula as possible, and injection of highly concentrated n‐BCA glue (70%‐90%) in a transarterial approach. After multiple rounds of embolization, feeders become less dilated and may be difficult to distinguish from angiogenesis. In this pattern, we use low‐concentrate nBCA (40%‐50%) from an identifiable, proximal feeder and occlude the venous component of the fistula. We identified two patterns of secondary angiogenesis: 1) pre‐interventional angiogenesis identified at the initial diagnostic angiogram, 2) de‐novo, post‐interventional angiogenesis during the staged‐embolization treatment‐course. Occasionally, we noted random bursts of angiogenesis. A combination of the hypoxic environment, inflammation, and hemodynamic alterations to the VGAM caused by liquid embolic/coiling may lead to a burst of angiogenesis that subsides after repeated treatment. We hypothesize that the immature sinuses typically associated with VGAM patients, which experience a decrease in blood flow and subsequently narrow after embolization, may contribute to turbulent blood flow. Development of parenchymal and subarachnoid angiogenesis is common during the multi‐session treatment of VGAM. It represents the response to the angiogenic stimuli released from the draining vein. This angiogenesis can be observed to regress spontaneously or mature as we continue to treat the VGAM. It is unnecessary to embolize secondary angiogenesis outright and it is our recommendation to chiefly target primary feeders of the VGAM as close to the venous component as possible.

Altered Coupling Between Resting-State Cerebral Blood Flow and Functional Connectivity Strength in Cervical Spondylotic Myelopathy Patients

Background: Changes in regional neural activity and functional connectivity in cervical spondylotic myelopathy (CSM) patients have been reported. However, resting-state cerebral blood flow (CBF) changes and coupling between CBF and functional connectivity in CSM patients are largely unknown.Methods: Twenty-seven CSM patients and 24 sex/age-matched healthy participants underwent resting-state functional MRI and arterial spin labeling imaging to compare functional connectivity strength (FCS) and CBF between the two groups. The CBF–FCS coupling of the whole gray matter and specific regions of interest was also compared between the groups.Results: Compared with healthy individuals, CBF–FCS coupling was significantly lower in CSM patients. The decrease in CBF–FCS coupling in CSM patients was observed in the superior frontal gyrus, bilateral thalamus, and right calcarine cortex, whereas the increase in CBF–FCS coupling was observed in the middle frontal gyrus. Moreover, low CBF and high FCS were observed in sensorimotor cortices and visual cortices, respectively.Conclusion: In general, neurovascular decoupling at cortical level may be a potential neuropathological mechanism of CSM.

Brain Volumetric Alterations in Preclinical HIV-Associated Neurocognitive Disorder Using Automatic Brain Quantification and Segmentation Tool

PurposeThis study aimed to determine if people living with HIV (PLWH) in preclinical human immunodeficiency virus (HIV)-associated neurocognitive disorder (HAND), with no clinical symptoms and without decreased daily functioning, suffer from brain volumetric alterations and its patterns.MethodFifty-nine male PLWH at the HAND preclinical stage were evaluated, including 19 subjects with asymptomatic neurocognitive impairment (ANI), 17 subjects with cognitive abnormality that does not reach ANI (Not reach ANI), and 23 subjects with cognitive integrity. Moreover, 23 healthy volunteers were set as the seronegative normal controls (NCs). These individuals underwent sagittal three-dimensional T1-weighted imaging (3D T1WI). Quantified data and volumetric measures of brain structures were automatically segmented and extracted using AccuBrain®. In addition, the multiple linear regression analysis was performed to analyze the relationship of volumes of brain structures and clinical variables in preclinical HAND, and the correlations of the brain volume parameters with different cognitive function states were assessed by Pearson’s correlation analysis.ResultsThe significant difference was shown in the relative volumes of the ventricular system, bilateral lateral ventricle, thalamus, caudate, and left parietal lobe gray matter between the preclinical HAND and NCs. Furthermore, the relative volumes of the bilateral thalamus in preclinical HAND were negatively correlated with attention/working memory (left: r = −0.271, p = 0.042; right: r = −0.273, p = 0.040). Higher age was associated with increased relative volumes of the bilateral lateral ventricle and ventricular system and reduced relative volumes of the left thalamus and parietal lobe gray matter. The lower CD4+/CD8+ ratio was associated with increased relative volumes of the left lateral ventricle and ventricular system. Longer disease course was associated with increased relative volumes of the bilateral thalamus. No significant difference was found among preclinical HAND subgroups in all indices, and the difference between the individual groups (Not reach ANI and Cognitive integrity groups) and NCs was also insignificant. However, there was a significant difference between ANI and NCs in the relative volumes of the bilateral caudate and lateral ventricle.ConclusionMale PLWH at the HAND preclinical stage suffer from brain volumetric alterations. AccuBrain® provides potential value in evaluating HIV-related neurocognitive dysfunction.

Interaction of Chemotherapy and Radiotherapy in Altering the Morphology of Subcortical Structures in Patients With Nasopharyngeal Carcinoma

Neuroimaging studies have found significant structural alterations of the cerebral cortex in patients with nasopharyngeal carcinoma (NPC) following radiotherapy (RT) or concomitant chemoradiotherapy (CCRT), while their effects on the morphology of subcortical structures remain largely unknown. In this study, we investigated the subcortical morphological alterations between three groups: 56 untreated NPC patients (pre-RT group), 37 RT-treated NPC patients (post-RT group), and 108 CCRT-treated NPC patients (post-CCRT group). Using FSL-FIRST, we found that, compared with the pre-RT group, the post-CCRT group exhibited morphological atrophy in the bilateral thalamus, bilateral putamen, left pallidum, and left caudate and morphological inflation in the left caudate, while the post-RT group only exhibited morphological atrophy in the bilateral thalamus. We also found a significant negative correlation between the maximum dosage of RT for temporal lobes and the morphological changes of the bilateral thalamus in treated NPC patients. These results indicated that there may be an interaction between RT and CT that can cause subcortical damage.

Cortical and Subcortical Grey Matter Abnormalities in White Matter Hyperintensities and Subsequent Cognitive Impairment

Grey matter (GM) alterations may contribute to cognitive decline in individuals with white matter hyperintensities (WMH) but no consensus has yet emerged. Here, we investigated cortical thickness and grey matter volume in 23 WMH patients with mild cognitive impairment (WMH-MCI), 43 WMH patients without cognitive impairment, and 55 healthy controls. Both WMH groups showed GM atrophy in the bilateral thalamus, fronto-insular cortices, and several parietal-temporal regions, and the WMH-MCI group showed more extensive and severe GM atrophy. The GM atrophy in the thalamus and fronto-insular cortices was associated with cognitive decline in the WMH-MCI patients and may mediate the relationship between WMH and cognition in WMH patients. Furthermore, the main results were well replicated in an independent dataset from the Alzheimer's Disease Neuroimaging Initiative database and in other control analyses. These comprehensive results provide robust evidence of specific GM alterations underlying WMH and subsequent cognitive impairment.

Thalamic dysconnectivity in the psychosis risk syndrome and early illness schizophrenia

Background Schizophrenia (SZ) is associated with thalamic dysconnectivity. Compared to healthy controls (HCs), individuals with SZ have hyperconnectivity with sensory regions, and hypoconnectivity with cerebellar, thalamic, and prefrontal regions. Despite replication of this pattern in chronically ill individuals, less is known about when these abnormalities emerge in the illness course and if they are present prior to illness onset. Methods Resting-state functional magnetic resonance imaging data were collected from psychosis risk syndrome (PRS) youth (n = 45), early illness SZ (ESZ) (n = 74) patients, and HCs (n = 85). Age-adjusted functional connectivity, seeded from the thalamus, was compared among the groups. Results Significant effects of group were observed in left and right middle temporal regions, left and right superior temporal regions, left cerebellum, and bilateral thalamus. Compared to HCs, ESZ demonstrated hyperconnectivity to all temporal lobe regions and reduced connectivity with cerebellar, anterior cingulate, and thalamic regions. Compared to HCs, PRS demonstrated hyperconnectivity with the left and right middle temporal regions, and hypoconnectivity with the cerebellar and other thalamic regions. Compared to PRS participants, ESZ participants were hyperconnected to temporal regions, but did not differ from PRS in hypoconnectivity with cerebellar and thalamic regions. Thalamic dysconnectivity was unrelated to positive symptom severity in ESZ or PRS groups. Conclusions PRS individuals demonstrated an intermediate level of thalamic dysconnectivity, whereas ESZ showed a pattern consistent with prior observations in chronic samples. These cross-sectional findings suggest that thalamic dysconnectivity may occur prior to illness onset and become more pronounced in early illness stages.

Correlation Between Cerebral Venous Oxygen Level and Cognitive Status in Patients With Alzheimer’s Disease Using Quantitative Susceptibility Mapping

PurposeTo quantitatively assess the blood oxygen levels of the cerebral vein using quantitative susceptibility mapping (QSM), and to analyze the correlation between magnetic susceptibility value (MSV) and clinical laboratory indicators/cognitive scores in patients with Alzheimer’s disease (AD).Materials and MethodsFifty-nine patients (21 males and 38 females) with clinically confirmed AD (AD group) and 22 control subjects (12 males, 10 females; CON group) were recruited. Clinical data and laboratory examination indexes were collected. All patients underwent Mini-mental State Examination, Montreal Cognitive Assessment, Clock Drawing Task, and Activity of Daily Living Scale test, as well as a routine MRI and enhanced gradient echo T2 star weighted angiography (ESWAN).ResultsHigher cerebral venous MSV was observed in AD group compared to CON group, significant differences were observed for bilateral thalamus veins and left dentate nucleus veins. The MSV of bilateral thalamus veins, bilateral internal cerebral veins, and bilateral dentate nucleus veins had significant negative correlation with Mini-mental State Examination score; the MSV of bilateral thalamus veins, bilateral dentate nucleus veins, right septal vein had a significant negative correlation with Montreal Cognitive Assessment scores; a significant negative correlation between the MSV of bilateral thalamus veins, left dentate nucleus vein, right septal vein and the Clock Drawing Task score; the MSV of bilateral thalamus veins, left dentate nucleus vein had a significant negative correlation with Activity of Daily Living Scale score. The MSV of left dentate nucleus vein was positively correlated with the course of the disease, the MSV of bilateral septal vein were positively correlated with the total cholesterol, and the MSV of left septal vein had a positive correlation with LDL.ConclusionDecreasing cerebral venous oxygen level in AD patients may affect cognitive status, and associated with the deterioration of the disease in AD patients.