Virchow-Robin space dilatation may predict resistance to antidepressant monotherapy in elderly patients with depression.

BACKGROUND: Late-life depressive disorders have been linked to cerebrovascular disease (the vascular depression hypothesis). Treatment resistance may be associated with vascular-based lesions in the white matter and basal ganglia. Virchow-Robin spaces (VRS) are cerebrospinal fluid spaces associated with microangiopathy of small cerebral vessels. This study tested the hypothesis that dilation of Virchow-Robin spaces seen on Magnetic Resonance Imaging (MRI) is associated with treatment resistance in elderly depressed individuals. METHODS: 50 patients with late-onset (age over 60 years) major depressive disorder (29 responders to monotherapy, 21 non-responders to monotherapy) and 35 normal volunteers were recruited. Assessment of deep white matter lesions [WML] and periventricular hyperintensities [PVH] (both with the Scheltens rating scale score, [Scheltens, P., Barkhof, F., Leys, D., et al. (1993) A semiquantative rating scale for the assessment of signal hyperintensities on magnetic resonance imaging. J Neurol Sci;114(1):7-12.]) and the severity of VRS dilatation (using a new scale) were scored from MRI images. Statistical group comparisons and multiple regression analyses were performed to quantify the relationship between imaging features and clinical outcome. RESULTS: There was a trend for greater WML Scheltens scores in the monotherapy resistant group compared to responders and control subjects, but only using the basal ganglia VRS score was there a statistically significant difference. A score of 2 or greater on the VRS score was 80% sensitive and 62% specific in predicting non-response to antidepressant monotherapy. The VRS score accounted for 38% of the variance in the multiple regression model and the PVH score, which was an independent predictor of outcome, contributed another 6%. LIMITATIONS: Numbers are small and type II errors possible, especially for the Scheltens ratings. Treatment response was limited to response or non-response to monotherapy and was retrospectively derived. The VRS scale was originally designed for use in patients with vascular dementia and has not been used before in affective disorders. Although all depressed subjects were late-onset, it is possible that depression led to vascular disease rather than vice versa. CONCLUSION: VRS dilatation is common in diseases associated with microvascular abnormality, which is the presumed basis of vascular depression in the elderly. VRS score may be useful in determining which patients are less likely to respond to antidepressant monotherapy. Prospective studies of patients with a wider range of treatment responses are indicated.

Is volume transfer coefficient (K(trans)) related to histologic grade in human gliomas?

PURPOSE: The purpose of this study was to examine the relationship between contrast transfer coefficient [K(trans)] and grade in gliomas. MATERIAL AND METHODS: Median values of K(trans), CBV(T1), and of the 95th percentile (95%) of the distribution (K(trans) [95%] and CBV(T1) [95%]) were calculated in 39 patients with glioma. Group comparisons and post hoc pairwise comparisons were performed. The relationship between variables and grade used Spearman rho and canonical discriminant analysis. The separation of high- from low-grade tumors was separately assessed by using Mann-Whitney U tests and logistic regression. Receiver operator curve analysis was performed for high- and low-grade tumors and grade III and grade IV tumors. RESULTS: There were significant differences between grades for all variables (P < .001). Pairwise comparisons demonstrated significant differences between grades II and III and II and IV for all variables except K(trans), which did not show significance in the grade II and III comparison, and between III and IV for CBV(T1) and CBV(T1) (95%; P < .01). All variables correlated with grade (P < .01). Discriminant analysis showed independent relation between both CBV(T1) and K(trans) (95%) and grade, and the canonical function produced a total correct classification of 74.4% of cases. Logistic regression analysis for low- versus high-grade tumors showed K(trans) (95%) and CBV(T1) to be independent factors (P < .01 and P < .05). CONCLUSION: There are strong independent relationships between both CBV and K(trans) and histologic grade in gliomas. Both measurements show good discriminative power in distinguishing between low- and high-grade tumors with diagnostic sensitivity and specificity >90%.

Dilatation of the Virchow-Robin space is a sensitive indicator of cerebral microvascular disease: study in elderly patients with dementia.

BACKGROUND AND PURPOSE: Virchow-Robin spaces (VRSs) are CSF spaces that accompany blood vessels as they perforate the brain substance. Dilatation of VRS is associated with microangiopathy. Microvascular disease has a major etiologic and pathogenetic role in dementias. To our knowledge, no investigators have looked at the relationship between dilated VRS on MR imaging and cerebral microvascular disease. The aim of our study was to test the hypothesis that dilatation of VRS is associated with subcortical vascular dementia. METHODS: We recruited 75 patients with Alzheimer's disease (n = 35), ischemic vascular dementia (n = 24), or frontotemporal dementia (n = 16) and 35 healthy volunteers. We assessed deep white matter and periventricular hyperintensities and the severity of VRS dilatation, as scored on MR images. Statistical group comparisons and multiple regression analyses were performed to quantify the relationship between imaging features and diagnoses. RESULTS: White matter lesions were more common in patients with ischemic vascular dementia than in those with Alzheimer's disease or healthy volunteers (P < .01). VRS scores were significantly higher in patients with vascular dementia than in patients with AD (P < .001), patients with FTD (P < .01), or healthy volunteers (P < .001). VRS scores accounted for 29% of the variance in the regression model, and scores for periventricular hyperintensity accounted for 2%. CONCLUSION: VRS dilatation is common in diseases associated with microvascular abnormality and can be used as a diagnostic tool to differentiate vascular dementias from degenerative dementias.

Adult cerebral malaria: prognostic importance of imaging findings and correlation with postmortem findings.

PURPOSE: To correlate imaging abnormalities, clinical features, and postmortem findings in patients with proved cerebral malaria. MATERIALS AND METHODS: Twenty-one patients aged 17-50 years with cerebral malaria consented to undergo transverse nonenhanced (10-mm sections) and contrast material-enhanced (8-mm sections in posterior fossa and 10-mm sections in supratentorial region) CT on admission (n = 21) and on day 10 (n = 6), with thin sections (5 mm) obtained in the area of abnormality. All CT scans were evaluated for diffuse cerebral edema, focal parenchymal abnormalities, and hemorrhage. CT findings were categorized as normal, diffuse cerebral edema, and edema with thalamic hypoattenuation without or with cerebellar hypoattenuation. Spearman rank correlation test was performed. RESULTS: Initial scans were normal in seven patients with mild disease (median Acute Physiology and Chronic Health Evaluation [APACHE] II score of 7, median Glasgow Coma Scale [GCS] score of 10), and all survived. Of eight patients with diffuse cerebral edema (GCS > or = 8; median APACHE II, 21), six survived. Cerebral edema with thalamic and cerebellar white matter hypoattenuation was seen in five patients. All had GCS score of 6 or less, median APACHE II score of 26, and multiorgan failure; none survived. One patient (GCS = 6) had thalamic hypoattenuation without cerebellar lesions. He survived with mild residual hemiparesis. Diffuse petechial hemorrhages were seen in the cerebrum and cerebellum at autopsy in all seven patients who died. These petechial hemorrhages were not visualized on CT scans. CT findings did not correlate with degree of parasitemia. CONCLUSION: CT findings correlate well with level of consciousness and severity of disease but underestimate the extent of disease at pathologic examination. A normal CT scan indicates a favorable outcome, whereas cerebellar hypoattenuation portends a poor outcome.