Israel Medical Association Journal

Endovascularly retrieved clots may be a potential resource for diagnosing stroke etiology. This method may influence secondary prevention treatment. We measure thrombin activity eluted by serially washing clots. We concluded that an assay measuring the change in thrombin in clots retrieved during acute stroke endovascular thrombectomy procedures may serve as a diagnostic marker of the origin of the clot. The suggested mechanism for these differences may be the clot location before its retrieval, with high blood flow causing thrombin washout in atherosclerotic clots, in contrast to atrium appendage low blood flow retaining high thrombin levels.

Background: Enthesopathy may lead to calcification of the stylohyoid ligament and can cause elongation of the styloid process (SP).

Objectives: To evaluate whether SP elongation is associated with two common enthesitis-related diseases: ankylosing spondylitis (AS) and diffuse idiopathic skeletal hyperostosis (DISH).

Methods: Cervical spine computed tomography (CT) examinations of patients with DISH (n=64, Resnick criteria), AS (n=24, New York criteria) and a controls (no radiological signs of DISH or AS, n=54) were retrospectively evaluated. The DISH group was further divided into patients with and without cervical DISH. The length of right and left SP was measured independently by two readers on coronal and sagittal curved reformats. The average right and left styloid length and average length per person were compared among the groups.

Results: Demographic characteristics were similar between the DISH and control groups (average age 68.2 ± 15.7, 69.2 ± 12.7 years, male:female ratio 48:16 and 35:19, respectively, P > 0.05), whereas age was significantly lower (average age: 53 ± 15 years, P < 0.0001) in the AS group, which was also composed mainly of men. The AS and DISH groups had significantly longer SP compared to controls (AS 37.9 ± 9.6 mm, DISH 34.4 ± 9 mm, control 30.3 ± 10.1 mm, P < 0.05). There was no correlation between age and SP length. Inter-reader reliability of SP measurements was excellent in all groups (ICC = 0.998, P < 0.0001).

Conclusions: SP elongation is associated with both AS and DISH substantiating the enthesopathy-related pathophysiology of this finding.

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.