Cerebral Vasospasm: A Review Findlay, J. Max; Nisar, Joshua; Darsaut, Tim
Canadian journal of neurological sciences,
01/2016, Letnik:
43, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Cerebral vasospasm is a prolonged but reversible narrowing of cerebral arteries beginning days after subarachnoid hemorrhage. Progression to cerebral ischemia is tied mostly to vasospasm severity, ...and its pathogenesis lies in artery encasement by blood clot, although the complex interactions between hematoma and surrounding structures are not fully understood. The delayed onset of vasospasm provides a potential opportunity for its prevention. It is disappointing that recent randomized, controlled trials did not demonstrate that the endothelin antagonist clazosentan, the cholesterol-lowering agent simvastatin, and the vasodilator magnesium sulfate improve patient outcome. Minimizing ischemia by avoiding inadequate blood volume and pressure, administering the calcium antagonist nimodipine, and intervention with balloon angioplasty, when necessary, constitutes current best management. Over the past two decades, our ability to manage vasospasm has led to a significant decline in patient morbidity and mortality from vasospasm, yet it still remains an important determinant of outcome after aneurysm rupture.
Vasospasme cérébral : revue du sujet. Le vasospasme cérébral consiste en un rétrécissement prolongé mais réversible d’une artère cérébrale débutant dans les jours suivant une hémorragie sous-arachnoïdienne (HSA). La progression vers l’ischémie cérébrale est liée surtout à la sévérité du vasospasme et sa pathogenèse est en lien avec le caillot formant une gaine autour de l’artère. Cependant, les interactions complexes entre l’hématome et les structures environnantes demeurent mal connues. Le délai entre l’HSA et le vasospasme fournit une occasion potentielle de prévention. Des essais contrôlés randomisés récents n’ont pas démontré que le clazosentan, un antagoniste de l’endothéline, la simvastatine, un hypocholestérolémiant, ou le sulfate de magnésium, un vasodilatateur, améliorent le résultat chez le patient. Actuellement, le meilleur traitement consiste à minimiser l’ischémie en s’assurant que le volume sanguin et la tension artérielle sont adéquats, en administrant de la nimodipine, un antagoniste du calcium, et en procédant à une angioplastie par ballonnet si nécessaire. Au cours des vingt dernières années, une diminution significative de la morbidité et de la mortalité due au vasospasme a été observée grâce à ces moyens de traitement. Cependant le vasospasme demeure un important déterminant de l’issue chez le patient après la rupture d’un anévrisme cérébral.
Atypical teratoid/rhabdoid tumor in adults is a relatively rare malignant neoplasm. It is characterized by the presence of rhabdoid cells in combination with loss of either the INI1 or BRG1protein ...from the tumor cells.
A systematic review was conducted using MEDLINE using the terms "atypical teratoid rhabdoid tumor" AND "adult." The systematic review was supplemented with relevant articles from the references. Cases were included if the pathology was confirmed by loss of INI1 or BRG1. We included a case from our institution. The dataset was analyzed using descriptive statistics and log-rank test.
A total of 50 cases from 29 articles were included in this study. The average age at diagnosis was 36.7 years. The most common locations reported are the sellar region and cerebral hemispheres (without deep gray matter involvement). Of the 50 cases, 14 were reported to show evidence of dissemination. The average overall survival was 20 months. There was a significant difference in survival between the adjuvant therapy groups (
= < 0.0001).
Atypical teratoid rhabdoid tumor of the central nervous system in adults is a rare neoplasm associated with a poor prognosis in a majority of patients. The treatment and clinical course are highly variable, and it remains unclear which factors impact prognosis.
Recurrence of chronic subdural haematomas (CSDHs) after surgical drainage is a significant problem with rates up to 20%. This study focuses on determining factors predictive of haematoma recurrence ...and presents a scoring system stratifying recurrence risk for individual patients.
Between the years 2005 and 2009, 331 consecutive patients with CSDHs treated with surgery were included in this study. Univariate and multivariate analyses were performed searching for risk factors of increased post-operative haematoma volume and haematoma recurrence requiring repeat drainage.
We found a 12% reoperation rate. CSDH septation (seen on computed tomogram scan) was found to be an independent risk factor for recurrence requiring reoperation (p=0.04). Larger post-operative subdural haematoma volume was also significantly associated with requiring a second drainage procedure (p<0.001). Independent risk factors of larger post-operative haematoma volume included septations within a CSDH (p<0.01), increased pre-operative haematoma volume (p<0.01), and a greater amount of parenchymal atrophy (p=0.04). A simple scoring system for quantifying recurrence risk was created and validated based on patient age (< or ≥ 80 years), haematoma volume (< or ≥ 160 cc), and presence of septations within the subdural collection (yes or no).
Septations within CSDHs are associated with larger post-operative residual haematoma collections requiring repeat drainage. When septations are clearly visible within a CSDH, craniotomy might be more suitable as a primary procedure as it allows greater access to a septated subdural collection. Our proposed scoring system combining haematoma volume, age, and presence of septations might be useful in identifying patients at higher risk for recurrence.
Acute blood pressure (BP) reduction aimed at attenuation of intracerebral hemorrhage (ICH) expansion might also compromise cerebral blood flow (CBF). We tested the hypothesis that CBF in acute ICH ...patients is unaffected by BP reduction.
Patients with spontaneous ICH <24 hours after onset and systolic BP > 150 mm Hg were randomly assigned to an intravenous antihypertensive treatment protocol targeting a systolic BP of <150 mm Hg (n=39) or <180 mm Hg (n=36). Patients underwent computed tomography perfusion imaging 2 hours postrandomization. The primary end point was perihematoma relative (relative CBF).
Treatment groups were balanced with respect to baseline systolic BP: 182±20 mm Hg (<150 mm Hg target group) versus 184±25 mm Hg (<180 mm Hg target group; P=0.60), and for hematoma volume: 25.6±30.8 versus 26.9±25.2 mL (P=0.66). Mean systolic BP 2 hours after randomization was significantly lower in the <150 mm Hg target group (140±19 vs 162±12 mm Hg; P<0.001). Perihematoma CBF (38.7±11.9 mL/100 g per minute) was lower than in contralateral homologous regions (44.1±11.1 mL/100 g per minute; P<0.001) in all patients. The primary end point of perihematoma relative CBF in the <150 mm Hg target group (0.86±0.12) was not significantly lower than that in the <180 mm Hg group (0.89±0.09; P=0.19; absolute difference, 0.03; 95% confidence interval -0.018 to 0.078). There was no relationship between the magnitude of BP change and perihematoma relative CBF in the <150 mm Hg (R=0.00005; 95% confidence interval, -0.001 to 0.001) or <180 mm Hg target groups (R=0.000; 95% confidence interval, -0.001 to 0.001).
Rapid BP lowering after a moderate volume of ICH does not reduce perihematoma CBF. These physiological data indicate that acute BP reduction does not precipitate cerebral ischemia in ICH patients. Clinical Trial Registration Information- URL:http://clinicaltrials.gov. Unique Identifier: NCT00963976.
Unruptured intracranial aneurysms (UIAs) are increasingly diagnosed and are commonly treated using endovascular treatment or microsurgical clipping. The safety and efficacy of treatments have not ...been compared in a randomised trial. How to treat patients with UIAs suitable for both options remains unknown.
We randomly allocated clipping or coiling to patients with one or more 3-25 mm UIAs judged treatable both ways. The primary outcome was treatment failure, defined as: initial failure of aneurysm treatment, intracranial haemorrhage or residual aneurysm on 1-year imaging. Secondary outcomes included neurological deficits following treatment, hospitalisation >5 days, overall morbidity and mortality and angiographic results at 1 year.
The trial was designed to include 260 patients. An analysis was performed for slow accrual: 136 patients were enrolled from 2010 through 2016 and 134 patients were treated. The 1-year primary outcome, available for 104 patients, was reached in 5/48 (10.4% (4.5%-22.2%)) patients allocated surgical clipping, and 10/56 (17.9% (10.0%-29.8%)) patients allocated endovascular coiling (OR: 0.54 (0.13-1.90), p=0.40). Morbidity and mortality (modified Rankin Scale>2) at 1 year occurred in 2/48 (4.2% (1.2%-14.0%)) and 2/56 (3.6% (1.0%-12.1%)) patients allocated clipping and coiling, respectively. New neurological deficits (15/65 vs 6/69; OR: 3.12 (1.05-10.57), p=0.031), and hospitalisations beyond 5 days (30/65 vs 6/69; OR: 8.85 (3.22-28.59), p=0.0001) were more frequent after clipping.
Surgical clipping or endovascular coiling of UIAs did not show differences in morbidity at 1 year. Trial continuation and additional randomised evidence will be necessary to establish the supposed superior efficacy of clipping.
As with other specialties, Royal College of Physicians and Surgeons of Canada (RCPSC) trainees in Neurosurgery have anecdotally had challenges securing full-time employment. This study presents the ...employment status, research pursuits, and fellowship choices of neurosurgery trainees in Canadian programs.
RCPSC neurosurgery trainees (n = 143) who began their residency training between 1998 and 2008 were included in this study. Associations between year of residency completion, research pursuits, and fellowship choice with career outcomes were determined by Fisher's exact test (p < 0.05, statistical significance).
In 2015, 60% and 26% of neurosurgery trainees had permanent positions in Canada and the USA, respectively. Underemployment, defined as locum and clinical associate positions, pursuit of multiple unrelated fellowships, unemployment, and career change to non-surgical career, was 12% in 2015. The proportion of neurosurgery trainees who had been underemployed at some point within 5 years since residency completion was 20%. Pursuit of in-folded research (MSc, PhD, or non-degree research greater than 1 year) was significantly associated with obtaining full employment (94% vs. 73%, p = 0.011). However, fellowship training was not significantly associated with obtaining full employment (78% vs. 75%, p = 1.000).
Underemployment in neurosurgery has become a significant issue in Canada for various reasons. Pursuit of in-folded research, but not fellowship training, was associated with obtaining full employment.
Whether the best management of middle cerebral artery (MCA) aneurysm patients is surgical or endovascular remains uncertain, with little evidence to guide decision-making. A randomized care trial ...offering MCA aneurysm patients a 50% chance of surgical and a 50% chance of endovascular management may optimize outcomes in the presence of uncertainty.
The Middle Cerebral Artery Aneurysm Trial (MCAAT) is an investigator-initiated, multicenter, parallel group, prospective, 1:1 randomized controlled clinical trial. All adult patients with MCA aneurysms, ruptured or unruptured, amenable to surgical and endovascular treatment can be included. The composite primary outcome is “Treatment Success”: (i) occlusion or exclusion of the aneurysm using the allocated treatment modality; (ii) no intracranial hemorrhage during follow-up; (iii) no retreatment of the target aneurysm during follow-up, (iv) no residual aneurysm on angiographic follow-up; and (v) independence (mRS <3) at 1 year. The trial tests 2 versions of the same hypothesis (one for ruptured and one for unruptured MCA aneurysm patients): Surgical management will lead to a 15% absolute increase in the proportion of patients reaching Treatment Success from 55% to 70% (ruptured) or from 75% to 90% (unruptured aneurysm patients) compared with endovascular treatment (any method). In this pragmatic trial, outcome evaluations are by treating physicians, except for 1-year angiographic results which will be core lab assessed. The trial will be monitored by an independent data safety monitoring committee to assure safety of participants. MCAAT is registered at clinicaltrials.gov: NCT05161377.
Patients with MCA aneurysms can be optimally managed within a care trial protocol.
Once a decision has been made to treat an intact aneurysm, the best treatment remains uncertain. Both surgical and endovascular management strategies are commonly performed for these lesions. ...Surgical clipping, for years the standard treatment, is gradually becoming supplanted by endovascular treatment. However, there is no randomized data available to compare the results of surgery versus endovascular treatment of unruptured aneurysms (UIAs).
We report the design of the Canadian UnRuptured Endovascular versus Surgery (CURES) trial to compare angiographic and clinical outcomes following treatment of UIAs.
The Canadian pilot phase will serve two purposes: i) to determine feasibility of the pivotal international study, and ii) to determine the incidence of treatment failure, a composite primary end-point comprising the occurrence of either: failure to accomplish aneurysm obliteration with the initial treatment modality, a major saccular aneurysm remnant or recurrence, or intracranial hemorrhage following treatment at one year. The pivotal international study will address which strategy leads to the best overall clinical outcomes in terms of mortality, morbidity, and clinical efficacy. CURES is designed to be a pragmatic management trial with loose inclusion criteria. The pilot study plans to enroll 260 patients, a size sufficient (at 80% power and 0.05 significance) to detect a decrease in the incidence of treatment failure from 13% to 4%. The formulation of specific hypotheses for the pivotal phase awaits the preliminary CURES morbidity and mortality results.
The CURES trial intends to test surgical versus endovascular management strategies for the treatment of unruptured intracranial aneurysms.
Cross-clamp ischemia during carotid endarterectomy can be prevented with carotid bypass shunts in vulnerable patients identified by cerebral monitoring for ischemia. We compared transcranial cerebral ...oximetry (TCO) with carotid stump pressure measurements for selective shunt use.
We prospectively collected data on 300 consecutive patients operated on under general anesthesia between 2009 and 2016. Shunts were inserted for a 10% or greater drop in cerebral saturations and/or a mean stump pressure less than 40 mmHg.
Seventy-five patients, 25% of the study population, were shunted. The indication was a combined desaturation and stump pressure in 38 (50% of the shunted group), desaturation alone in 11 patients (15%), and a low stump pressure alone in 26 patients (35%). There were no significant differences in baseline characteristics between those patients who were or were not shunted, except angiographic collateral blood supply, which was more commonly identified in patients who were not shunted. A watershed infarct occurred in just one patient with borderline TCO and stump pressure measurements in whom a shunt was not used.
There was poor concordance between TCO and stump pressures, but using both in determining the need for shunt use almost eliminated cross-clamp ischemia in this series of 300 carotid endarterectomy patients.
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