Israel Medical Association Journal

Background: Only a small proportion of schizophrenia patients present with catatonic symptoms. Imaging studies suggest that brain motor circuits are involved in the underlying pathology of catatonia. However, data about diffusivity dysregulation of these circuits in catatonic schizophrenia are scarce.

Objectives: To assess the involvement of brain motor circuits in schizophrenia patients with catatonia.

Methods: Diffusion tensor imaging (DTI) was used to measure white matter signals in selected brain regions linked to motor circuits. Relevant DTI data of seven catatonic schizophrenia patients were compared to those of seven non-catatonic schizophrenia patients, matched for sex, age, and education level.

Results: Significantly elevated fractional anisotropy values were found in the splenium of the corpus callosum, the right peduncle of the cerebellum, and the right internal capsule of the schizophrenia patients with catatonia compared to those without catatonia. This finding showed altered diffusivity in selected motor-related brain areas.

Conclusions: Catatonic schizophrenia is associated with dysregulation of the connectivity in specific motoric brain regions and corresponding circuits. Future DTI studies are needed to address the neural correlates of motor abnormalities in schizophrenia-related catatonia during the acute and remitted state of the illness to identify the specific pathophysiology of this disorder.

Mechanical thrombectomy with stent retrievers is now the reference therapy for acute ischemic stroke (AIS) in the anterior circulation in association with thrombolysis. We conducted an extensive systematic review and meta-analysis to evaluate the clinical and angiographic outcomes of stent-retriever thrombectomy in patients with acute anterior circulation stroke. Available literature published to date on observational studies and three randomized trials (MR CLEAN, ESCAPE, and EXTEND-IA) involving the stent-retriever device were reviewed. Successful recanalization and favorable clinical outcome were defined by a TICI ≥ 2b and modified Rankin Scale score of ≤ 2 at 90 days following AIS, respectively. A total of 2067 patients harboring an anterior circulation stroke were treated with a stent retriever: 433 patients from 3 randomized trials involving the device and 1634 patients from observational studies. Mean NIH Stroke Scale score on admission was 16.6, and mean time from onset to recanalization was 300 minutes. Successful recanalization was achieved in 82% (95%CI 77–86, 31 studies). The 90 day favorable outcome was achieved in 47% (95%CI 42–5.2, 34 studies) with an overall mortality rate of 17% (95%CI 13–20, 31 studies). Symptomatic intracerebral hemorrhage was identified in 6% (95%CI 4–8, 32 studies). In patients with AIS caused by a proximal intracranial occlusion of the anterior circulation, stent-retriever thrombectomy is safe and restores brain reperfusion in four of five treated patients, allowing favorable clinical outcome in one of two AIS patients with large vessel occlusion. 

Objectives: To evaluate common misinterpretations of head CT scans by radiology residents in a level I trauma center ED.

Methods: We studied 960 head CT scans of patients admitted to our ED from January 2010 to May 2011. They were reviewed separately by two senior neuroradiologists and graded as being unimportant (score of 1), important but not requiring emergent treatment (score of 2), and important requiring urgent treatment (score of 3). We recorded the time of day the examination was performed, the year of residency, the site, subsite and side of the lesion, the pathology, the anatomical mistake, false-positive findings, and the attending neuroradiologists' score.

Results: A total of 955 examinations were interpreted of which 398 had misinterpreted findings that were entered into the database, with the possibility of multiple errors per examination. The overall misinterpretation rate was 41%. The most commonly missed pathologies were chronic infarcts, hypodense lesions, and mucosal thickening in the paranasal sinuses. The most common sites for misdiagnosis were brain lobes, sinuses and deep brain structures. The highest percentage of misinterpretation occurred between 14:30 and 20:00, and the lowest between 00:00 and 08:00 (P < 0.05). The overall percentage of errors involving pathologies with a score of 3 by at least one of the neuroradiologists was 4.7%. Third-year residents had an overall higher error rate and first-year residents had significantly more false-positive misinterpretations compared to the other residents.

Conclusions: The percentage of errors made by our residents in cases that required urgent treatment was comparable to the published data. We believe that the intense workload of radiology residents contributes to their misinterpretation of head CT findings.

Objectives: To assess the ability of perfusion-weighted imaging to differentiate between high grade gliomas and brain metastases.

Methods: During 5 months, 21 patients (age 40–85, median age 61, 16 males and 5 females) with either glioblastoma multiforme (GBM) or metastasis (pathology proven), underwent MRI for assessment of the tumor prior to surgery. Most of the scans were done at 3 Tesla. The scans included perfusion-weighted imaging sequences. Perfusion in the tumor, in the peritumoral edema and in normal tissue were assessed using Functool® software. The ratios of tumor perfusion and peritumoral edema perfusion to normal tissue perfusion were calculated and compared.

Results: Bleeding artifact precluded perfusion assessment in four patients. There was no statistically significant difference between the tumor perfusion ratios of high grade gliomas and those of metastases. The edema perfusion ratios were higher in GBM than in metastases (P = 0.007).

Conclusions: Perfusion-weighted imaging of peritumoral edema can help to differentiate between GBM and metastases.