J. Marc C. van Dijk

International subarachnoid aneurysm trial 2009: endovascular coiling of ruptured intracranial aneurysms has no significant advantage over neurosurgical clipping.

In the May 2009 issue of The Lancet Neurology, the 5-year follow-up results of the International Subarachnoid Aneurysm Trial (ISAT) were published. The authors concluded that, although the significant difference between coiling and neurosurgical clipping of ruptured intracranial aneurysms in terms of death and severe disability after 1 year has vanished (primary endpoint), coiling should still be favored over neurosurgical clipping because mortality rates significantly favored coiling. In this commentary, it is this particular conclusion that is challenged by combining data from previous ISAT publications with the current 5-year follow-up results. This modified intent-to-treat analysis clearly demonstrates that the significant advantage in terms of mortality in favor of the endovascularly treated patients is no longer present, with a hazard ratio of 0.80 in favor of endovascular treatment (95% confidence interval: 0.60-1.05; P = .10). Therefore, for everyday clinical practice and decision making, coiling and clipping are to be considered equivalent in the long term.

Predictive Factors for Rebleeding After Aneurysmal Subarachnoid Hemorrhage: Rebleeding Aneurysmal Subarachnoid Hemorrhage Study

Background and Purpose— Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating type of stroke associated with high morbidity and mortality. One of the most feared complications is an early rebleeding before aneurysm repair. Predictors for such an often fatal rebleeding are largely unknown. We therefore aimed to determine predictors for an early rebleeding after aSAH in relation with time after ictus. Methods— This observational prospective cohort study included all consecutive patients admitted with aSAH between January 1998 and December 2014 (n=1337) at our University Neurovascular Center. Clinical predictors for rebleeding ⩽24 hours were identified using multivariable Cox regression analyses. Kaplan–Meier analyses were applied to evaluate the time of rebleeding ⩽72 hours after aSAH. Results— A modified Fisher grade of 3 to 4 was a predictor for an in-hospital rebleeding ⩽24 hours after ictus (adjusted hazard ratio, 4.4; 95% confidence interval, 2.1–10.6; P<0.001). The numbers needed to treat to prevent 1 rebleeding ⩽24 hours was calculated 15 (95% confidence interval, 10–25). Also, the initiation of external cerebrospinal fluid-drainage (adjusted hazard ratio, 1.9; 95% confidence interval, 1.4–2.5; P<0.001) was independently associated with a rebleeding ⩽24 hours. Cumulative in-hospital rebleeding rates were 5.8% ⩽24 hours, and 1.2% in the time frame 24–72 hours after ictus. Conclusions— In our opinion, timing of treatment of aSAH patients, especially those with an modified Fisher grade of 3 or 4 in a good clinical condition, should be reconsidered. These aSAH patients might be regarded a medical emergency, requiring aneurysm repair as soon as possible. In this respect, our findings should provoke the debate on timing of aneurysm repair, especially in patients considered to be at high risk for rebleeding.

Feasibility of magnetic resonance angiography (MRA) follow-up as the primary imaging modality after coiling of intracranial aneurysms.

Background: Digital subtraction angiography (DSA) is still regarded as the gold standard for detecting residual flow in treated aneurysms. Recent reports have also shown excellent results from magnetic resonance angiography (MRA) imaging. This is an important observation, since DSA is associated with a risk of medical complications, is time consuming, and is more expensive. Purpose: To determine whether MRA could replace conventional DSA and serve as the primary postinterventional imaging modality in patients with coiled intracranial aneurysms. Material and Methods: We studied a prospectively enrolled cohort of 190 patients treated endovascularly for a first-ruptured and/or unruptured intracranial aneurysm between January 2004 and December 2008. The imaging protocol included a 1.5T time-of-flight (TOF) MRA and a DSA at 3 months (on the same day) and, depending on comparability, a 1.5T TOF-MRA or DSA 1 year after treatment. All images were evaluated by a multidisciplinary panel. Results: In 141/190 patients, both an MRA and DSA were performed after 3-month follow-up. In 2/141 patients (1.4%), (small) neck remnants gave false-negative MRA results. In one patient (0.7%), this led to additional neurosurgical clipping of the aneurysm. In 25/141 patients, future follow-up (>3 months) consisted of DSA because of various reasons. In 24/25 of these patients, primary MRA images alone would invariably have led to additional DSA imaging. Conclusion: The present study shows that 1.5T TOF-MRA is a feasible primary follow-up modality after coiling of intracranial aneurysms. Given our data, we now suggest that, in every patient with a coiled intracranial aneurysm, the first follow-up, 3 months after coiling, should be an MRA study. Only when this MRA is inconclusive (e.g., because of coil artifacts), or in the case of suspicion of recanalization, should DSA be performed additionally.

Thrombophilic factors and the formation of dural arteriovenous fistulas

OBJECT Dural arteriovenous fistulas (DAVFs) are distinct neurovascular entities. Although their exact origins are unknown, venous thrombosis and venous hypertension are likely to be major inducing factors. To address the relationship between DAVFs and thrombophilic factors, the authors conducted a case-control study at a single institution and performed a metaanalysis of the literature. METHODS Forty patients with DAVFs at Toronto Western Hospital were recruited to complete a questionnaire and to donate blood samples for factor V Leiden mutation and factor II G20210A mutation screening and assessment of coagulation factors. The questionnaire was designed to collect information on each participants specific history of venous thrombosis, medications, and race. A control group of 33 healthy volunteers agreed to the same protocol. A MEDLINE search of the literature from 1966 to the present was conducted and three relevant series were found. The results of the present study were pooled with the data from the literature. RESULTS Combining institutional results with the results from the literature yielded a total of 121 patients and 178 control group members. Thrombophilic mutations were present in 16 patients and four healthy volunteers, with an odds ratio (OR) of 4.69 for factor V Leiden (95% confidence interval [CI] 1.24-17.69) and an OR of 10.87 for the prothrombin G20210A allele (95% CI 1.32-89.51). Levels of the basic coagulation profile, fibrinogen, and factor VIII were within normal limits. CONCLUSIONS Patients with the factor V Leiden and factor II G20210A mutations are at a higher risk for DAVFs. However, because these mutations are not implicated in the vast majority of DAVFs, routine screening is not recommended.

Recurrence Rates After Surgical or Endovascular Treatment of Spinal Dural Arteriovenous Fistulas : A Meta-analysis

BACKGROUND There is an increasing tendency to treat spinal dural arteriovenous fistulas (SDAVFs) endovascularly despite the lack of clear evidence favoring embolization over surgery. OBJECTIVE To compare the initial failure and recurrence rates of primary treatment of SDAVFs by surgery and endovascular techniques. METHODS A meta-analysis using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) standard was performed. All the English literature from 2004 onward was evaluated. From each article that compared the 2 treatment modalities, the odds ratio (OR) was calculated. Combined ORs were calculated with Review Manager 5.3 of The Cochrane Collaboration. RESULTS A total of 35 studies harboring 1112 patients were assessed. Initial definitive fistula occlusion was observed in 588 of 609 surgical patients (96.6%; 95% confidence interval [CI], 94.8-97.8) vs 363 of 503 endovascularly treated patients (72.2%; 95% CI, 68.1-75.9; P < .001). The combined OR from 18 studies that assessed both treatment modalities (730 patients) was 6.15 (95% CI, 3.45-11.0) in favor of surgical treatment. Late recurrence (13 studies, 480 patients) revealed an OR of 3.15 (95% CI, 1.66-5.96; P < .001) in favor of surgery. In a subgroup, recurrence was reported in 10 of 22 patients (45%) treated with Onyx vs 8 of 35 (23%) treated with n-butyle-2-cyanoacrylate (OR, 2.51; 95% CI, 0.75-8.37; P = .13). CONCLUSION Although hampered by inclusion of poor quality studies, this meta-analysis shows a definite advantage of primary surgical treatment of SDAVF over endovascular treatment in initial failure rate and late recurrences. The often-used argument that endovascular techniques have improved and therefore outweigh surgery is not supported by this meta-analysis.

The Natural History of Dural Arteriovenous Shunts: The Toronto Experience

To the Editor: With interest we have read the article “Natural history of dural arteriovenous shunts” by Soderman et al1 in Stroke . We agree that the dural arteriovenous shunt still is a puzzling neurovascular entity that poses a challenge in knowing the natural disease course. Therefore, every attempt to analyze large series and particularly the events during follow-up should be eluded to. However, things should also be seen in perspective and so, to avoid erroneous conclusions by the reader, we want to make some critical comments. First of all, the authors differentiate 3 separate periods of time at risk: the …

Clinical and Physiological Events That Contribute to the Success Rate of Finding "Optimal" Cerebral Perfusion Pressure in Severe Brain Trauma Patients

Objective:Recently, a concept of an individually targeted level of cerebral perfusion pressure that aims to restore impaired cerebral vasoreactivity has been advocated after traumatic brain injury. The relationship between cerebral perfusion pressure and pressure reactivity index normally is supposed to have a U-shape with its minimum interpreted as the value of “optimal” cerebral perfusion pressure. The aim of this study is to investigate the relation between the absence of the optimal cerebral perfusion pressure curve and physiological variables, clinical factors, and interventions. Design:Retrospective analysis of prospectively collected data. Setting:Neurocritical care units in two university centers. Patients:Between May 2012 and December 2013, a total of 48 traumatic brain injury patients were studied with real-time annotation of predefined clinical events. InterventionsNone. Measurements and Main Results:All patients had continuous monitoring of arterial blood pressure, intracranial pressure, and cerebral perfusion pressure, with real-time calculations of pressure reactivity index and optimal cerebral perfusion pressure using ICM+ software (Cambridge Enterprise, University of Cambridge, Cambridge, UK). Selected clinical events were inserted on a daily basis, including changes in physiological variables, sedativeanalgesic drugs, vasoactive drugs, and medical/surgical therapies for intracranial hypertension. The collected data were divided into 4-hour periods, with the primary outcome being absence of the optimal cerebral perfusion pressure curve. For every period, mean values (± SDs) of arterial blood pressure, intracranial pressure, pressure reactivity index, and other physiological variables were calculated; clinical events were organized using predefined scales. In 28% of all 1,561 periods, an optimal cerebral perfusion pressure curve was absent. A generalized linear mixed model with binary logistic regression was fitted. Absence of slow arterial blood pressure waves (odds ratio, 2.7; p < 0.001), higher pressure reactivity index values (odds ratio, 2.9; p < 0.001), lower amount of sedative-analgesic drugs (odds ratio, 1.9; p = 0.03), higher vasoactive medication dose (odds ratio, 3.2; p = 0.02), no administration of maintenance neuromuscular blockers (odds ratio, 1.7; p < 0.01), and following decompressive craniectomy (odds ratio, 1.8; p < 0.01) were independently associated with optimal cerebral perfusion pressure curve absence. Conclusions:This study identified six factors that were independently associated with absence of optimal cerebral perfusion pressure curves.

Appreciation of CT-negative, lumbar puncture-positive subarachnoid haemorrhage: risk factors for presence of aneurysms and diagnostic yield of imaging

Objective Patients without a subarachnoid haemorrhage (SAH) on brain CT scan (CT-negative), but a lumbar puncture (LP)-proven SAH, are a challenging patient category. The optimal diagnostic approach is still a matter of debate. Also, there is little knowledge on the probability of finding an underlying vascular lesion. Design In this observational study, a consecutive cohort of 94 patients with CT-negative, LP-positive SAH was prospectively collected between 1998 and 2013. The yield of diagnostic modalities as well as patient outcome was studied. In addition, risk factors for the presence of a vascular lesion were analysed. Results In 40 patients (43%), an intracranial vascular abnormality was detected: 37 aneurysms and three arterial dissections. Female gender was significantly associated with detection of a vascular lesion. Time between ictus and diagnosis of SAH was not associated with the presence of vascular pathology. Overall, 99% of patients had a modified Rankin Score of 0–2 after a median follow-up of 72 months. The yield of additional digital subtraction angiography in patients with a negative CT angiography was zero. Conclusions In this study, the chance of finding a vascular lesion in a patient with CT-negative, LP-positive SAH was 43%, underlining the need for an adequate diagnostic workup. In general, the patient outcome was favourable. Female gender was found to be predictive for detecting a vascular lesion. In contrast with previous reports, the interval between ictus and LP was not associated with the presence of an aneurysm.

Prediction of outcome after subarachnoid hemorrhage: Timing of clinical assessment

OBJECTIVE Currently, early prediction of outcome after spontaneous subarachnoid hemorrhage (SAH) lacks accuracy despite multiple studies addressing this issue. The clinical condition of the patient on admission as assessed using the World Federation of Neurosurgical Societies (WFNS) grading scale is currently considered the gold standard. However, the timing of the clinical assessment is subject to debate, as is the contribution of additional predictors. The aim of this study was to identify either the conventional WFNS grade on admission or the WFNS grade after neurological resuscitation (rWFNS) as the most accurate predictor of outcome after SAH. METHODS This prospective observational cohort study included 1620 consecutive patients with SAH admitted between January 1998 and December 2014 at our university neurovascular center. The primary outcome measure was a poor modified Rankin Scale score at the 2-month follow-up. Clinical predictors were identified using multivariate logistic regression analyses. Area under the receiver operating characteristic curve (AUC) analysis was used to test discriminative performance of the final model. An AUC of > 0.8 was regarded as indicative of a model with good prognostic value. RESULTS Poor outcome (modified Rankin Scale Score 4-6) was observed in 25% of the patients. The rWFNS grade was a significantly stronger predictor of outcome than the admission WFNS grade. The rWFNS grade was significantly associated with poor outcome (p < 0.001) as well as increasing age (p < 0.001), higher modified Fisher grade (p < 0.001), larger aneurysm size (p < 0.001), and the presence of an intracerebral hematoma (OR 1.8, 95% CI 1.2-2.8; p = 0.002). The final model had an AUC of 0.87 (95% CI 0.85-0.89), which indicates excellent prognostic value regarding the discrimination between poor and good outcome after SAH. CONCLUSIONS In clinical practice and future research, neurological assessment and grading of patients should be performed using the rWFNS to obtain the best representation of their clinical condition.

Repeat microvascular decompression for recurrent idiopathic trigeminal neuralgia

OBJECTIVE Microvascular decompression (MVD) is considered the method of choice to treat idiopathic trigeminal neuralgia (TN) refractory to medical treatment. However, repeat MVD for recurrent TN is not well established. In this paper, the authors describe a large case series in which patients underwent repeat MVD for recurrent TN, focusing on outcome, risk factors, and complication rates. METHODS Between 1990 and 2012, a total of 33 consecutive patients underwent repeat MVD for recurrent TN at the University Medical Center Groningen. The authors performed a retrospective chart review and telephone interviews. Risk factors were analyzed by binary logistic regression analysis. RESULTS After 12 months of follow-up, 22 (67%) operations were successful, of which 19 patients were completely free of pain without medication. With multivariate analysis significant risk factors for success were older age (OR 1.11, p < 0.01) and direct absence of pain after repeat MVD (OR 25.2, p < 0.01). Previous neurodestructive procedures did not influence success rates. Facial numbness occurred in 9 patients (27%), while other morbidity was minimal. There was no mortality. CONCLUSIONS This study demonstrates that repeat MVD is a feasible therapeutic option with good chances of success, even in patients who have undergone neurodestructive procedures. Complication rates, particularly facial numbness, can be avoided if only a limited neurolysis is performed.