An Illustrative Review of the Pathomechanisms of Symptomatic Developmental Venous Anomalies.

OBJECTIVE: Symptomatic developmental venous anomalies (DVAs) are rare. Here, we illustrate the varied clinicoradiologic profiles of symptomatic DVAs and contemplate the mechanisms that render these (allegedly) benign entities symptomatic supported by a review of literature. METHODS: Institutional databases were searched to identify cases of symptomatic DVAs. Clinical and imaging (angiographic and cross-sectional) data of 9 cases with 11 neurovascular symptoms consequent to inflow/outflow perturbations and mechanical obstruction that manifested because of the strategic topography of underlying DVAs were analyzed. A review of the existing literature on DVAs in agreement with our case series was performed on publications retrieved from the PubMed database. RESULTS: Symptoms secondary to venous hypertension arising from flow-related perturbations were broadly divided into those arising from restricted outflow and increased inflow. Restricted outflow occurred because of collector vein stenosis (n = 2) and collector vein/DVA thrombosis (n = 3), whereas the latter pathomechanism was initiated by arterialized/transitional DVAs (n = 2). A mechanical/obstructive pathomechanism culminating in moderate supratentorial ventriculomegaly was noted in 1 case. One patient was given a diagnosis of hemorrhage associated with a cavernoma. CONCLUSIONS: Awareness and contextualization of potential flow-related perturbations and mechanical insults that render DVAs symptomatic aid in accurate diagnosis, management, and prognostication.

Utility of 3D T1-weighted turbo spin echo black blood sequence for the diagnosis of cerebral venous thrombosis.

PURPOSE: Accurate assessment of dural sinus, deep and cortical venous thrombosis on MR imaging is challenging. The aim of this study is to evaluate the accuracy of 3D-T1 turbo spin echo (T1S), sequences in detecting venous thrombosis and comparing it with susceptibility-weighted imaging (SWI), magnetic resonance venography (MRV) and post contrast T1 magnetization-prepared rapid acquisition gradient echo (T1C). METHODS: A blinded retrospective observational analysis of 71 consecutive patients evaluated for cerebral venous thrombosis (CVT) and 30 control patients was performed. Multimodality reference standard adopted included T1C, SWI with MRV. Sub-analyses in superficial, deep and cortical venous segments were performed in addition to correlation of signal intensity of thrombus with the clinical stage. RESULTS: A total of 2222 segments in 101 complete MRI examinations were evaluated. Sensitivity/specificity/positive predictive value/negative predictive value/accuracy and precision of T1S for detection of cortical vein thrombosis was 0.994/1/1/0.967/0.995/1, 1/0.874/0.949/1/0.963/0.950 for detection of superficial venous sinus thrombosis and 1/1/1/1/1/1 for deep venous thrombosis. The AUC yield for T1S was 0.997 for cortical, 1 for deep and 0.988 for superficial venous segments. CONCLUSION: T1S paralleled the accuracy of conventional sequences in the overall detection of CVT but showed superior accuracy in the detection of cortical venous thrombosis. It makes a fitting addition to the CVT MRI protocol in scenarios demanding negation of gadolinium administration.

Cryptococcus gattii: A Poseur to Behold!

Cryptococcosis is an invasive systemic mycosis caused by Cryptococcus, a genus of yeast. Causative organisms for human cryptococcosis include Cryptococcus neoformans and Cryptococcus gattii. Disease due to C.neoformans is conventionally seen in patients with underlying immunosuppression, whereas C.gattii-related infection is usually seen in immunocompetent people. The fact that the infection can occur among otherwise healthy individuals underscores the importance of having a necessary understanding of the pathophysiology and clinical and radiological presentations of the disease. We report a case of disseminated pulmonary and central nervous system (CNS) cryptococcosis in an apparently immunocompetent individual with unusual radiological findings necessitating probing for alternative diagnoses. We have attempted to supplement and revise the existing data on the radiological manifestations of C.gattii.

Parry Romberg syndrome: Imaging features in 4 consecutive cases and review of literature.

Parry Romberg syndrome (PRS) is a distinct sporadic self-limiting entity comprising progressive hemi- atrophy of the face with predisposition to affect the skin, subcutaneous tissue and in some cases deeper extension to the cartilage, osseous structures and musculature (Wong et al., 2015; Aydin et al., 2015; Sharma et al., 2012) [1-3]. Neurologic and ocular involvement is variable as is the progression of this entity. With a multitude of aetiologies ranging from autoimmune to infectious this syndrome is a diagnosis of exclusion, with a highly variable prognosis, drawing the amusement of radiologists and clinicians. Radiological assessment and subsequent diagnosis of this entity can aid in alleviating the lifestyle hampering progression of this disease process. We hereby report 4 cases of this syndrome and aim to describe the varied radiological presentations of this entity with concise review of literature.

Changes in resting-state functional brain activity are associated with waning cognitive functions in HIV-infected children.

Delayed brain development in perinatally HIV-infected children may affect the functional brain activity and subsequently cognitive function. The current study evaluated the functional brain activity in HIV-infected children by quantifying the amplitude of low frequency fluctuations (ALFF) and functional connectivity (FC). Additionally, correlation of ALFF and FC with cognitive measures was performed. Twenty-six HIV-infected children and 20 control children underwent neuropsychological (NP) assessment and resting-state functional magnetic resonance imaging (rs-fMRI). ALFF and FC maps were generated and group differences were analyzed using two-sample t-test. Furthermore, ALFF and FC showing significant group differences were correlated with NP scores using Pearson's correlation. Significantly lower ALFF in the left middle temporal gyrus, precentral and post central gyrus was observed in HIV-infected children compared to controls. FC was significantly reduced in the right inferior parietal, vermis, middle temporal and left postcentral regions, and significantly increased in the right precuneus, superior parietal and left middle frontal regions in HIV-infected children as compared to control. HIV-infected children showed significantly lower NP scores in various domains including closure, exclusion, memory, verbal meaning, quantity and hidden figure than controls. These waning cognitive functions were significantly associated with changes in ALFF and FC in HIV-infected children. The findings suggest that abnormal ALFF and FC may responsible for cognitive deficits in HIV-infected children. ALFF and FC in association with cognitive evaluation may provide a clinical biomarker to evaluate functional brain activity and to plan neurocognitive intervention in HIV-infected children undergoing standard treatment.