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BACKGROUND AND PURPOSE: Conventional angiography is the benchmark examination to diagnose cerebral vasospasm, but there is limited evidence regarding its reliability. Our goals were the following: 1) to systematically review the literature on the reliability of the diagnosis of cerebral vasospasm using conventional angiography, and 2) to perform an agreement study among clinicians who perform endovascular treatment. MATERIALS AND METHODS: Articles reporting a classification system on the degree of cerebral vasospasm on conventional angiography were systematically searched, and agreement studies were identified. We assembled a portfolio of 221 cases of patients with subarachnoid hemorrhage and asked 17 raters with different backgrounds (radiology, neurosurgery, or neurology) and experience (junior ≤10 and senior >10 years) to independently evaluate cerebral vasospasm in 7 vessel segments using a 3-point scale and to evaluate, for each case, whether findings would justify endovascular treatment. Nine raters took part in the intraobserver reliability study. RESULTS: The systematic review showed a very heterogeneous literature, with 140 studies using 60 different nomenclatures and 21 different thresholds to define cerebral vasospasm, and 5 interobserver studies reporting a wide range of reliability (κ = 0.14–0.87). In our study, only senior raters reached substantial agreement (κ ≥ 0.6) on vasospasm of the supraclinoid ICA, M1, and basilar segments and only when assessments were dichotomized (presence or absence of ≥50% narrowing). Agreement on whether to proceed with endovascular management of vasospasm was only fair (κ ≤ 0.4). CONCLUSIONS: Research on cerebral vasospasm would benefit from standardization of definitions and thresholds. Dichotomized decisions by experienced readers are required for the reliable angiographic diagnosis of cerebral vasospasm.

MCA aneurysms are still commonly clipped surgically despite the recent development of a number of endovascular tools and techniques. We measured clinical uncertainty by studying the reliability of decisions made for patients with middle cerebral artery (MCA) aneurysms.A portfolio of 60 MCA aneurysms was presented to surgical and endovascular specialists who were asked whether they considered surgery or endovascular treatment to be an option, whether they would consider recruitment of the patient in a randomized trial, and whether they would provide their final management recommendation. Agreement was studied using κ statistics. Intrarater reliability was assessed with the same, permuted portfolio of cases of MCA aneurysm sent to the same specialists 1 month later.Surgical management was the preferred option for neurosurgeons (Individual clinicians did not agree regarding the best management of patients with MCA aneurysms. A randomized trial comparing endovascular with surgical management of patients with MCA aneurysms is in order.

BACKGROUND AND PURPOSE: After aneurysmal SAH, transcranial Doppler is commonly used to monitor cerebral vasospasm. The diagnostic accuracy of transcranial Doppler flow velocity values in detecting angiographic vasospasm in patients requiring urgent endovascular intervention has not been established. MATERIALS AND METHODS: We performed a retrospective analysis of a consecutive series of patients with aneurysmal SAH who underwent transcranial Doppler (index test) within 24 hours of conventional angiography (reference test). The judgment of 33%, 50%, and 66% degree of vessel narrowing on angiography was independently established by multiple neuroendovascular clinicians. Vessel-specific per-segment and per-patient transcranial Doppler velocities were studied using receiver operating characteristic curves, the Youden index, and minimal acceptable sensitivity models. Optimal mean flow-velocity thresholds were explored to calculate sensitivity and specificity using a per-patient judgment of vasospasm of at least 50% angiographic narrowing in any large arterial segment except A1. RESULTS: In 221 patients, vasospasm was found in 15%, 8%, and 4% of arteries when the degree of reference angiographic luminal narrowing was 33%, 50%, and 66%, respectively. Mean flow velocities were significantly higher in vasospastic segments (P = . 001), but per-segment exploratory analyses yielded unsound mean flow velocity thresholds. The Youden and minimal acceptable sensitivity models proposed mean flow velocity thresholds of approximately 160 cm/s for the anterior circulation and 80 cm/s for the posterior circulation in the per-patient diagnosis of angiographic vasospasm (≥50%), yielding a sensitivity of 80%–90% (95% CI, 0.77–0.96), but with a corresponding specificity of 50% (95% CI, 0.40–0.56). CONCLUSIONS: In this study, a threshold transcranial Doppler mean flow-velocity value that would accurately diagnose ≥50% angiographic vasospasm remained elusive.

Background and purpose Appropriate management of ruptured intracranial aneurysm (RIA) in patients eligible for surgical clipping but under-represented in or excluded from previous randomized trials remains undetermined. Methods The International Subarachnoid Aneurysm Trial-2 (ISAT-2) is a randomized care trial comparing surgical versus endovascular treatment (EVT) of RIA. All patients considered for surgical clipping but eligible for endovascular treatment can be included. The primary endpoint is death or dependency on modified Rankin score (mRS > 2) at 1 year. Secondary endpoints are 1 year angiographic results and length of hospital stay. Results An interim analysis was performed after 103 patients were treated from November 2012 to July 2017 in 4 active centers. Fifty-two of the 55 patients allocated to surgery were treated by clipping, and 45 of the 48 allocated to EVT were treated by coiling, with 3 crossovers in each arm. The main endpoint (1 year mRS > 2), available for 76 patients, was reached in 16/42 patients allocated to clipping (38%; 95%CI: 25%–53%), and 10/34 patients allocated to coiling (29%; 17%–46%). One year imaging results were available in 54 patients: complete aneurysm occlusion was found in 23/27 patients allocated to clipping (85%; 67%–94%), and 18/27 patients allocated to coiling (67%; 47%–81%). Hospital stay exceeding 20 days was more frequent in surgery (26/55 [47%; 34%–60%]) than EVT (9/48 [19%; 10%–31%]). Conclusion Ruptured aneurysm patients for whom surgical clipping may still be best can be managed in a randomized care trial, which is feasible in some centers. More participating centers are needed.

Background:Endovascular therapy (ET) is infrequently used in the setting of acute penetrating intracranial trauma.Methods:We report a case where ET was used immediately prior to and following removal of an embedded intracranial knife, which was found to be disrupting the anterior cerebral artery.Results:The proximal vessel was coiled and angiographically occluded and then the knife was removed with the microcatheter in place. Immediate angiography allowed us to see and quickly treat the contrast extravasation with further coiling. Despite full medical management, the patient died of elevated intracranial pressure.Conclusion:In this severely injured patient, endovascular therapy represented the most suitable means to attempt safe removal of the knife.

One hundred double contrast enema examinations using a colonic activator (veripaque) in the preliminary cleansing enema and 51 conventional barium enema examinations without a preliminary veripaque enema have been performed on 94 patients with either ulcerative colitis or Crohn's disease of the colon. The severity of the disease at barium enema examination has been graded and compared with the severity of the disease found at sigmoidoscopy. In the double contrast examination, there was agreement between the radiological and sigmoidoscopic findings in 77% of cases and a disagreement of one grade in the remaining 23% of cases. The double contrast enema demonstrated lesions in the colon proximal to the range of the sigmoidoscope of a greater severity than that seen at sigmoidoscopy in 30% of cases. It was not found possible to use the same grading method with the conventional enema, and unless frank ulceration is present, it is considered that the conventional enema is unreliable in assessing the state of the colonic mucosa. It is concluded that the double contrast enema, using a colonic activator in the preliminary cleansing enema, causes no greater risk of complications than either the conventional enema or sigmoidoscopy.

A study is made of certain properties of a model cell network based on lateral inhibition. It is demonstrated that specific patterns of input activity, termed eigenpatterns, will pass through the network without distortion. Under certain conditions the network will show selectivity for one particular eigenpattern, and the degree of this selectivity is under the control of non-specific parameters of the network.

Results are presented from an experiment to measure the magnitude of translational head movements during steady fixation when the head was supported in various ways. The significance of the results for eye movement recording is discussed.

The effect of grating size on the threshold for a 30 cycle per degree grating pattern is investigated for various colours of illumination and target orientations. It is shown under certain conditions that the threshold decreases as the target size is increased, and this is attributed to spatial integration of information.

Bacteriological studies were carried out on samples of gastric juice obtained from 31 patients with peptic ulcer before and immediately after a month's course of cimetidine. After cimetidine there were major increases in both total bacterial counts and counts of nitrate-reducing organisms and qualitative changes suggesting the establishment of a flora which included large numbers of "faecal" organisms.