Neurosurgery Blog

Icon

Daily bibliographic review of the Neurosurgery Department. La Fe University Hospital. Valencia, Spain

Clinical course of untreated thalamic cavernous malformations: hemorrhage risk and neurological outcomes

J Neurosurg 127:480–491, 2017

The natural history of cerebral cavernous malformations (CMs) has been widely studied, but the clinical course of untreated thalamic CMs is largely unknown. Hemorrhage of these lesions can be devastating. The authors undertook this study to obtain a prospective hemorrhage rate and provide a better understanding of the prognosis of untreated thalamic CMs.

METHODS This longitudinal cohort study included patients with thalamic CMs who were diagnosed between 2000 and 2015. Clinical data were recorded, radiological studies were extensively reviewed, and follow-up evaluations were performed.

RESULTS A total of 121 patients were included in the study (56.2% female), with a mean follow-up duration of 3.6 years. The overall annual hemorrhage rate (subsequent to the initial presentation) was calculated to be 9.7% based on the occurrence of 42 hemorrhages over 433.1 patient-years. This rate was highest in patients (n = 87) who initially presented with hemorrhage and focal neurological deficits (FNDs) (14.1%) (c2 = 15.358, p < 0.001), followed by patients (n = 19) with hemorrhage but without FND (4.5%) and patients (n = 15) without hemorrhage regardless of symptoms (1.2%). The initial patient presentations of hemorrhage with FND (hazard ratio [HR] 2.767, 95% CI 1.336–5.731, p = 0.006) and associated developmental venous anomaly (DVA) (HR 2.510, 95% CI 1.275–4.942, p = 0.008) were identified as independent hemorrhage risk factors. The annual hemorrhage rate was significantly higher in patients with hemorrhagic presentation at diagnosis (11.7%, p = 0.004) or DVA (15.7%, p = 0.002). Compared with the modified Rankin Scale (mRS) score at diagnosis (mean 2.2), the final mRS score (mean 2.0) was improved in 37 patients (30.6%), stable in 59 patients (48.8%), and worse in 25 patients (20.7%). Lesion size (odds ratio [OR] per 0.1 cm increase 3.410, 95% CI 1.272–9.146, p = 0.015) and mRS score at diagnosis (OR per 1 point increase 3.548, 95% CI 1.815–6.937, p < 0.001) were independent adverse risk factors for poor neurological outcome (mRS score ≥ 2). Patients experiencing hemorrhage after the initial ictus (OR per 1 ictus increase 6.923, 95% CI 3.023–15.855, p < 0.001) had a greater chance of worsened neurological status.

CONCLUSIONS This study verified the adverse predictors for hemorrhage and functional outcomes of thalamic CMs and demonstrated an overall annual symptomatic hemorrhage rate of 9.7% after the initial presentation. These findings and the mode of initial presentation are useful for clinicians and patients when selecting an appropriate treatment, although the tertiary referral bias of the series should be taken into account.

Bypass surgery for complex middle cerebral artery aneurysms: an algorithmic approach to revascularization

J Neurosurg 127:463–479, 2017

Management of complex aneurysms of the middle cerebral artery (MCA) can be challenging. Lesions not amenable to endovascular techniques or direct clipping might require a bypass procedure with aneurysm obliteration. Various bypass techniques are available, but an algorithmic approach to classifying these lesions and determining the optimal bypass strategy has not been developed. The objective of this study was to propose a comprehensive and flexible algorithm based on MCA aneurysm location for selecting the best of multiple bypass options.

METHODS Aneurysms of the MCA that required bypass as part of treatment were identified from a large prospectively maintained database of vascular neurosurgeries. According to its location relative to the bifurcation, each aneurysm was classified as a prebifurcation, bifurcation, or postbifurcation aneurysm.

RESULTS Between 1998 and 2015, 30 patients were treated for 30 complex MCA aneurysms in 8 (27%) prebifurcation, 5 (17%) bifurcation, and 17 (56%) postbifurcation locations. Bypasses included 8 superficial temporal artery–MCA bypasses, 4 high-flow extracranial-to-intracranial (EC-IC) bypasses, 13 IC-IC bypasses (6 reanastomoses, 3 reimplantations, 3 interpositional grafts, and 1 in situ bypass), and 5 combination bypasses. The bypass strategy for prebifurcation aneurysms was determined by the involvement of lenticulostriate arteries, whereas the bypass strategy for bifurcation aneurysms was determined by rupture status. The location of the MCA aneurysm in the candelabra (Sylvian, insular, or opercular) determined the bypass strategy for postbifurcation aneurysms. No deaths that resulted from surgery were found, bypass patency was 90%, and the condition of 90% of the patients was improved or unchanged at the most recent follow-up.

CONCLUSIONS The bypass strategy used for an MCA aneurysm depends on the aneurysm location, lenticulostriate anatomy, and rupture status. A uniform bypass strategy for all MCA aneurysms does not exist, but the algorithm proposed here might guide selection of the optimal EC-IC or IC-IC bypass technique.

Effect of statin treatment on vasospasm-related morbidity and functional outcome in patients with aneurysmal subarachnoid hemorrhage

J Neurosurg 127:291–301, 2017

The efficacy of statin therapy in treating aneurysmal subarachnoid hemorrhage (SAH) remains controversial. In this meta-analysis, the authors investigated whether statin treatment significantly reduced the incidence of cerebral vasospasm and delayed neurological deficits, promoting a better outcome after aneurysmal SAH.

METHODS: A literature search of the PubMed, Ovid, and Cochrane Library databases was performed for randomized controlled trials (RCTs) and prospective cohort studies investigating the effect of statin treatment. The end points of cerebral vasospasm, delayed ischemic neurological deficit (DIND), delayed cerebral infarction, mortality, and favorable outcome were statistically analyzed.

RESULTS Six RCTs and 2 prospective cohort studies met the eligibility criteria, and a total of 1461 patients were included. The meta-analysis demonstrated a significant decrease in the incidence of cerebral vasospasm (relative risk [RR] 0.76, 95% confidence interval [CI] 0.61–0.96) in patients treated with statins after aneurysmal SAH. However, no significant benefit was observed for DIND (RR 0.88, 95% CI 0.70–1.12), delayed cerebral infarction (RR 0.66, 95% CI 0.33–1.31), mortality (RR 0.69, 95% CI 0.39–1.24) or favorable outcome, according to assessment by the modified Rankin Scale or Glasgow Outcome Scale (RR 0.99, 95% CI 0.92–1.17).

CONCLUSIONS Treatment with statins significantly decreased the occurrence of vasospasm after aneurysmal SAH. The incidence of DIND, delayed cerebral infarction, and mortality were not affected by statin treatment. Future research should focus on DIND and how statins influence DIND.

 

Relationship of A1 segment hypoplasia to anterior communicating artery aneurysm morphology and risk factors for aneurysm formation

J Neurosurg 127:89–95, 2017

Hypoplasia of the A1 segment of the anterior cerebral artery is frequently observed in patients with anterior communicating artery (ACoA) aneurysms. The effect of this anatomical variant on ACoA aneurysm morphology is not well understood.

METHODS Digital subtraction angiography images were reviewed for 204 patients presenting to the authors’ institution with either a ruptured or an unruptured ACoA aneurysm. The ratio of the width of the larger A1 segment to the smaller A1 segment was calculated. Patients with an A1 ratio greater than 2 were categorized as having A1 segment hypoplasia. The relationship of A1 segment hypoplasia to both patient and aneurysm characteristics was then assessed.

RESULTS Of 204 patients that presented with an ACoA aneurysm, 34 (16.7%) were found to have a hypoplastic A1. Patients with A1 segment hypoplasia were less likely to have a history of smoking (44.1% vs 62.9%, p = 0.0410). ACoA aneurysms occurring in the setting of a hypoplastic A1 were also found to have a larger maximum diameter (mean 7.7 vs 6.0 mm, p = 0.0084). When considered as a continuous variable, increasing A1 ratio was associated with decreasing aneurysm dome-to-neck ratio (p = 0.0289). There was no significant difference in the prevalence of A1 segment hypoplasia between ruptured and unruptured aneurysms (18.9% vs 10.7%; p = 0.1605).

CONCLUSIONS Our results suggest that a hypoplastic A1 may affect the morphology of ACoA aneurysms. In addition, the relative lack of traditional risk factors for aneurysm formation in patients with A1 segment hypoplasia argues for the importance of hemodynamic factors in the formation of ACoA aneurysms in this anatomical setting.

 

Transdural arterial recruitment to brain arteriovenous malformation

J Neurosurg 127:51–58, 2017

The occurrence of transdural arterial recruitment (TDAR) in association with brain arteriovenous malformation (bAVM) is uncommon, and the reason for TDAR is not understood. The aim of this cohort study was to examine patient and bAVM characteristics associated with TDAR and the implications of TDAR on management.

METHODS A prospective surgical database of bAVMs was examined. Cases previously treated elsewhere or incompletely examined by digital subtraction angiography (DSA) assessment were excluded. Three studies of this cohort were performed, as follows: characteristics associated with TDAR, the relationship between TDAR and neurological deficits unassociated with hemorrhage (NDUH), and the impact of TDAR on outcome from surgery. Regression models were performed.

RESULTS Of 769 patients with complete DSA who had no previous treatment, 51 (6.6%) were found to have TDAR. The presence of TDAR was associated with increasing age (p < 0.01; OR 1.05; 95% CI 1.02–1.07); presentation with NDUH (p < 0.01; OR 2.71; 95% CI 1.29–5.71); increasing size of the bAVM (p < 0.01; OR 1.57; 95% CI 1.29–1.91); and combined supply from both anterior and posterior circulations (p = 0.02; OR 2.37; 95% CI 1.17–4.78). Further analysis of TDAR cases comparing those with and without NDUH found an association of larger size (6.6 cm [2.9 SD] compared with 4.7 cm [1.8 SD]; p < 0.01) and combined supply from both anterior and posterior circulations (relative risk 2.5; 95% CI 1.0–6.2; p = 0.04) to be associated with an NDUH presentation. For the 632 patients undergoing surgery there was an increased risk of complications (where this produced a new permanent neurological deficit at 12 months represented by a modified Rankin Scale score of > 1) with the following variables: size; location in eloquent brain; deep venous drainage; increasing age; and no presentation with hemorrhage. The presence of TDAR was not associated with an increased risk of complications from surgery.

CONCLUSIONS The authors found that TDAR occurs in older patients with larger bAVMs, and that TDAR is also more likely to be associated with bAVMs presenting with NDUH. The likely explanation for the presence of TDAR is a secondary recruitment arising as a consequence of shear stress, rather than a primary vascular supply present from the earliest development of the bAVM.

Bilateral chronic subdural hematoma: unilateral or bilateral drainage?

J Neurosurg 126:1905–1911, 2017

Bilateral chronic subdural hematoma (bCSDH) is a common neurosurgical condition frequently associated with the need for retreatment. The reason for the high rate of retreatment has not been thoroughly investigated. Thus, the authors focused on determining which independent predictors are associated with the retreatment of bCSDH with a focus on surgical laterality.

METHODS In a national database of CSDHs (Danish Chronic Subdural Hematoma Study) the authors retrospectively identified all bCSDHs treated in the 4 Danish neurosurgical departments over the 3-year period from 2010 to 2012. Univariate and multivariate analyses were performed to determine the relationship between retreatment of bCSDH and clinical, radiological, and surgical variables.

RESULTS Two hundred ninety-one patients with bCSDH were identified, and 264 of them underwent unilateral (136 patients) or bilateral (128 patients) surgery. The overall retreatment rate was 21.6% (57 of 264 patients). Cases treated with unilateral surgery had twice the risk of retreatment compared with cases undergoing bilateral surgery (28.7% vs 14.1%, respectively, p = 0.002). In accordance with previous studies, the data also showed that a separated hematoma density and the absence of postoperative drainage were independent predictors of retreatment.

CONCLUSIONS In bCSDHs bilateral surgical intervention significantly lowers the risk of retreatment compared with unilateral intervention and should be considered when choosing a surgical procedure.

 

Is there an inherited anatomical conformation favoring aneurysmal formation of the anterior communicating artery?

J Neurosurg 126:1598–1605, 2017

The pathophysiological mechanisms responsible for the formation of intracranial aneurysms (IAs) remain only partially elucidated. However, current evidence suggests a genetic component. The purpose of this study was to investigate the specific anatomical variations in the arterial complex that are associated with the presence of anterior communicating artery (ACoA) aneurysms in the familial forms of IAs.

METHODS This multicenter study investigated bifurcation IAs in patients who had a sporadic ACoA IA without a family history of IA (SACAA group), in patients who had an ACoA IA with a family history of IA (FACAA group), and in their healthy first-degree relatives (HFDRs). Through the use of MR angiography (MRA) reconstructions, the symmetry of the A1 segments and the angle between the A1 and A2 segments were analyzed on 3D models for each group. These measurements were then compared among the 3 groups.

RESULTS Twenty-four patients with SACAA, 24 patients with FACAA, and 20 HFDRs were included in the study. Asymmetrical configuration of the A1 segments was more frequent in the FACAA group than in the HFDR group (p = 0.002). The aneurysm-side A1-A2 angle was lower in the FACAA group (p = 0.003) and SACAA group (p = 0.007) than in the HFDR group. On the contralateral side, there was no difference in A1-A2 angles between groups.

CONCLUSIONS The anatomical shape of the ACoA complex seems to be similarly associated with the presence of ACoA IAs in both the FACAA and SACAA groups. This highlights the role played by hemodynamic constraints in aneurysm formation and questions the hypothesis of the hereditary character of these anatomical shapes.

Early diffusion-weighted MRI lesions after treatment of unruptured intracranial aneurysms:

J Neurosurg 126:1070–1078, 2017

Diffusion-weighted MRI was used to assess periprocedural lesion load after repair of unruptured intracranial aneurysms (UIA) by microsurgical clipping (MC) and endovascular coiling (EC).

METHODS Patients with UIA were assigned to undergo MC or EC according to interdisciplinary consensus and underwent diffusion-weighted imaging (DWI) 1 day before and 1 day after aneurysm treatment. Newly detected lesions by DWI after treatment were the primary end point of this prospective study. Lesions detected by DWI were categorized as follows: A) 1–3 DWI spots < 10 mm, B) > 3 DWI spots < 10 mm, C) single DWI lesion > 10 mm, or D) DWI lesion related to surgical access.

RESULTS Between 2010 and 2014, 99 cases were included. Sixty-two UIA were treated by MC and 37 by EC. There were no significant differences between groups in age, sex, aneurysm size, occurrence of multiple aneurysms in 1 patient, or presence of lesions detected by DWI before treatment. Aneurysms treated by EC were significantly more often located in the posterior circulation (p < 0.001). Diffusion-weighted MRI detected new lesions in 27 (43.5%) and 20 (54.1%) patients after MC and EC, respectively (not significant). The pattern of lesions detected by DWI varied significantly between groups (p < 0.001). Microembolic lesions (A and B) found on DWI were detected more frequently after EC (A, 14 cases; B, 5 cases) than after MC (A, 5 cases), whereas C and D were rare after EC (C, 1 case) and occurred more often after MC (C, 12 cases and D, 10 cases). No procedure-related unfavorable outcomes were detected.

CONCLUSIONS According to the specific techniques, lesion patterns differ between MC and EC, whereas the frequency of new lesions found on DWI is similar after occlusion of UIA. In general, the lesion load was low in both groups, and lesions were clinically silent. Clinical trial registration no.: NCT01490463 (clinicaltrials.gov)

Hemorrhage from cerebral cavernous malformations

J Neurosurg 126:1079–1087, 2017

The aim of this paper is to define an overall cavernous malformation (CM) hemorrhage rate and risk factors for hemorrhage.

METHODS The authors performed a systematic, pooled analysis via the PubMed database through October 2015 using the terms “cavernoma,” “cavernous malformation,” “natural history,” “bleeding,” and “hemorrhage.” English-language studies providing annual rates and/or risk factors for CM hemorrhage were included. Data extraction, performed independently by the authors, included demographic data, hemorrhage rates, and hemorrhage risk factors.

RESULTS Across 12 natural history studies with 1610 patients, the mean age at presentation was 42.7 years old and 52% of patients (95% CI 49%–55%) were female. Presentation modality was seizure in 30% (95% CI 25%–35%), hemorrhage in 26% (95% CI 17%–37%), incidental in 17% (95% CI 9%–31%), and focal deficits only in 16% of cases (95% CI 11%–23%). CM location was lobar in 66% (95% CI 61%–70%), brainstem in 18% (95% CI 13%–24%), deep supratentorial in 8% (95% CI 6%–10%), and cerebellar in 8% (95% CI 5%–11%). Pooling 7 studies that did not assume CM presence since birth, the annual hemorrhage rate was 2.5% per patient-year over 5081.2 patient-years of follow-up (95% CI 1.3%–5.1%). Pooling hazard ratios across 5 studies that evaluated hemorrhage risk factors, prior CM hemorrhage was a significant risk factor for hemorrhage (HR 3.73, 95% CI 1.26–11.1; p = 0.02) while younger age, female sex, deep location, size, multiplicity, and associated developmental venous anomalies (DVAs) were not.

CONCLUSIONS Although limited by the heterogeneity of incorporated reports and selection bias, this study found prior hemorrhage to be a significant risk factor for CM bleeding, while age, sex, CM location, size, multiplicity, and associated DVAs were not. Future natural history studies should compound annual hemorrhage rate with prospective seizure and nonhemorrhagic neurological deficit rates.

Microsurgery for cerebral arteriovenous malformations: subgroup outcomes in a consecutive series of 288 cases

J Neurosurg 126:1056–1063, 2017

The objective of this study was to review the outcomes after microsurgical resection of cerebral arteriovenous malformations (AVMs) from a consecutive single-surgeon series. Clinical and imaging data were analyzed to address the following questions concerning AVM treatment in the post-ARUBA (A Randomized Trial of Unruptured Brain Arteriovenous Malformations) era. 1) Are the patients who present with unruptured or ruptured AVMs doing better at long-term follow-up? 2) Is the differentiation between Ponce Class A (Spetzler-Martin Grade I and II) patients versus Ponce Class B and C patients (Spetzler-Martin Grade III and IV) meaningful and applicable to surgical practice? 3) How did the ARUBA-eligible patients of this surgical series compare with the results reported in ARUBA?

METHODS Two hundred eighty-eight patients with cerebral AVMs underwent microsurgical resection between 1983 and 2012 performed by the same surgeon (J.S.). This is a prospective case collection study that represents a consecutive series. The results are based on prospectively collected, early-outcome data that were supplemented by retrospectively collected, follow-up data for 94% of those cases. The analyzed data included the initial presentation, Spetzler-Martin grade, obliteration rates, surgical and neurological complications, and frequency of pretreatment with embolization or radiosurgery. The total cohort was compared using “small-AVM,” Spetzler-Martin Grade I and II, and ARUBA-eligible AVM subgroups.

RESULTS The initial presentation was hemorrhage in 50.0% and seizures in 43.1% of patients. The series included 53 Spetzler-Martin Grade I (18.4%), 114 Spetzler-Martin Grade II (39.6%), 90 Spetzler-Martin Grade III (31.3%), 28 Spetzler- Martin Grade IV (9.7%), and 3 Spetzler-Martin Grade V (1.0%) AVMs. There were 144 unruptured and 104 ARUBAeligible cases. Preembolization was used in 39 cases (13.5%). The occlusion rates for the total series and small AVM subgroup were 99% and 98.7%, respectively. The mean follow-up duration was 64 months. Early neurological deterioration was seen in 39.2% of patients, of which 12.2% had permanent and 5.6% had permanent significant deficits, and the mortality rate was 1.7% (n = 5). Outcome was better for patients with AVMs smaller than 3 cm (permanent deficit in 7.8% and permanent significant deficit in 3.2% of patients) and Ponce Class A status (permanent deficit in 7.8% and significant deficit in 3.2% of patients). Unruptured AVMs showed slightly higher new deficit rates (but 0 instances of mortality) among all cases, and in the small AVM and Ponce Class A subgroups. Unruptured Spetzler-Martin Grade I and II lesions had the best outcome (1.8% permanent significant deficit), and ARUBA-eligible Spetzler-Martin Grade I and II lesions had a slightly higher rate of permanent significant deficits (3.2%).

CONCLUSIONS Microsurgery has a very high cure rate. Focusing microsurgical AVM resection on unruptured lesions smaller than 3 cm or on Spetzler-Martin Grade I and II lesions is a good strategy for minimizing long-term morbidity. Well-selected microsurgical cases lead to better outcomes than with multimodal interventions, as in the ARUBA treatment arm, or conservative treatment alone. Long-term prospective data collection is valuable.

Microsurgery for cerebral arteriovenous malformations: subgroup outcomes in a consecutive series of 288 cases

J Neurosurg 126:1056–1063, 2017

The objective of this study was to review the outcomes after microsurgical resection of cerebral arteriovenous malformations (AVMs) from a consecutive single-surgeon series. Clinical and imaging data were analyzed to address the following questions concerning AVM treatment in the post-ARUBA (A Randomized Trial of Unruptured Brain Arteriovenous Malformations) era. 1) Are the patients who present with unruptured or ruptured AVMs doing better at long-term follow-up? 2) Is the differentiation between Ponce Class A (Spetzler-Martin Grade I and II) patients versus Ponce Class B and C patients (Spetzler-Martin Grade III and IV) meaningful and applicable to surgical practice? 3) How did the ARUBA-eligible patients of this surgical series compare with the results reported in ARUBA?

METHODS Two hundred eighty-eight patients with cerebral AVMs underwent microsurgical resection between 1983 and 2012 performed by the same surgeon (J.S.). This is a prospective case collection study that represents a consecutive series. The results are based on prospectively collected, early-outcome data that were supplemented by retrospectively collected, follow-up data for 94% of those cases. The analyzed data included the initial presentation, Spetzler-Mar-tin grade, obliteration rates, surgical and neurological complications, and frequency of pretreatment with embolization or radiosurgery. The total cohort was compared using “small-AVM,” Spetzler-Martin Grade I and II, and ARUBA-eligible AVM subgroups.

RESULTS The initial presentation was hemorrhage in 50.0% and seizures in 43.1% of patients. The series included 53 Spetzler-Martin Grade I (18.4%), 114 Spetzler-Martin Grade II (39.6%), 90 Spetzler-Martin Grade III (31.3%), 28 Spetzler-Martin Grade IV (9.7%), and 3 Spetzler-Martin Grade V (1.0%) AVMs. There were 144 unruptured and 104 ARUBA-eligible cases. Preembolization was used in 39 cases (13.5%). The occlusion rates for the total series and small AVM subgroup were 99% and 98.7%, respectively. The mean follow-up duration was 64 months. Early neurological deterioration was seen in 39.2% of patients, of which 12.2% had permanent and 5.6% had permanent significant deficits, and the mortality rate was 1.7% (n = 5). Outcome was better for patients with AVMs smaller than 3 cm (permanent deficit in 7.8% and permanent significant deficit in 3.2% of patients) and Ponce Class A status (permanent deficit in 7.8% and significant deficit in 3.2% of patients). Unruptured AVMs showed slightly higher new deficit rates (but 0 instances of mortality) among all cases, and in the small AVM and Ponce Class A subgroups. Unruptured Spetzler-Martin Grade I and II lesions had the best outcome (1.8% permanent significant deficit), and ARUBA-eligible Spetzler-Martin Grade I and II lesions had a slightly higher rate of permanent significant deficits (3.2%).

CONCLUSIONS Microsurgery has a very high cure rate. Focusing microsurgical AVM resection on unruptured lesions smaller than 3 cm or on Spetzler-Martin Grade I and II lesions is a good strategy for minimizing long-term morbidity. Well-selected microsurgical cases lead to better outcomes than with multimodal interventions, as in the ARUBA treatment arm, or conservative treatment alone. Long-term prospective data collection is valuable.

Comparison of clipping and coiling in elderly patients with unruptured cerebral aneurysms

J Neurosurg 126:811–818, 2017

The comparative effectiveness of the 2 treatment options—surgical clipping and endovascular coiling—for unruptured cerebral aneurysms remains an issue of debate and has not been studied in clinical trials. The authors investigated the association between treatment method for unruptured cerebral aneurysms and outcomes in elderly patients.

METHODS The authors performed a cohort study of 100% of Medicare fee-for-service claims data for elderly patients who had treatment for unruptured cerebral aneurysms between 2007 and 2012. To control for measured confounding, the authors used propensity score conditioning and inverse probability weighting with mixed effects to account for clus- tering at the level of the hospital referral region (HRR). An instrumental variable (regional rates of coiling) analysis was used to control for unmeasured confounding and to create pseudo-randomization on the treatment method.

RESULTS During the study period, 8705 patients underwent treatment for unruptured cerebral aneurysms and met the study inclusion criteria. Of these patients, 2585 (29.7%) had surgical clipping and 6120 (70.3%) had endovascular coiling. Instrumental variable analysis demonstrated no difference between coiling and clipping in 1-year postoperative mortality (OR 1.25, 95% CI 0.68–2.31) or 90-day readmission rate (OR 1.04, 95% CI 0.66–1.62). However, clipping was associ- ated with a greater likelihood of discharge to rehabilitation (OR 6.39, 95% CI 3.85–10.59) and 3.6 days longer length of stay (LOS; 95% CI 2.90–4.71). The same associations were present in propensity score–adjusted and inverse probability–weighted models.

CONCLUSIONS In a cohort of Medicare patients, there was no difference in mortality and the readmission rate between clipping and coiling of unruptured cerebral aneurysms. Clipping was associated with a higher rate of discharge to a rehabilitation facility and a longer LOS.

Responses to aruba: a systematic review

J Neurosurg 126:486–494, 2017

The ARUBA study (A Randomized Trial of Unruptured Brain Arteriovenous Malformations [AVMs]) on unruptured brain AVMs has been the object of comments and editorials. In the present study the authors aim to systematically review critiques, discuss design issues, and propose a framework for future trials.

Methods: The authors performed a systematic review of the French and English literature on the ARUBA study published between January 2006 and February 2015. The electronic search, including the Cochrane Library, MEDLINE (PubMed and Ovid), CINAHL, and EMBASE databases, was complemented by hand searching and cross-referencing. The comments were categorized as items related to the design, the conduct, and the analysis and interpretation of the trial.

Results: Thirty-one articles or letters were identified. The pragmatic design, with heterogeneity of patients and lack of standardization of the treatment arm, were frequently stated concerns. The choice of outcome measures was repeatedly criticized. During the trial, low enrollment rates, selection bias, and premature interruption of enrollment were frequent comments. The short follow-up period, the lack of subgroup analyses, the lack of details on the results of the various treatments, and a contentious interpretation of results were noted at the analysis stage. A fundamental problem was the primary hypothesis testing conservative management. The authors believe that other trials are needed. Future trials could be pragmatic, test interventions stratified at the time of randomization, and look for long-term, hard clinical out- comes in a large number of patients.

Conclusions: In the authors’ view, the ARUBA trial is a turning point in the history of brain AVM management; future trials should aim at integrating trial methodology and clinical care in the presence of uncertainty.

Transulcal parafascicular minimally invasive approach to deep and subcortical cavernomas

J Neurosurg 125:1360–1366, 2016

Cavernomas comprise 8%–15% of intracranial vascular lesions, usually supratentorial in location and superficial. Cavernomas in the thalamus or subcortical white matter represent a unique challenge for surgeons in trying to identify and then use a safe corridor to access and resect the pathology.

Previous authors have described specific open microsurgical corridors based on pathology location, often with technical difficulty and morbidity.

This series presents 2 cavernomas that were resected using a minimally invasive approach that is less technically demanding and has a good safety profile. The authors report 2 cases of cavernoma: one in the thalamus and brainstem with multiple hemorrhages and the other in eloquent subcortical white matter. These lesions were resected through a transulcal parafascicular approach with a port-based minimally invasive technique.

In this series there was complete resection with no neurological complications. The transulcal parafascicular minimally invasive approach relies on image interpretation and trajectory planning, intraoperative navigation, cortical cannulation and subcortical space access, high-quality optics, and resection as key elements to minimize exposure and retraction and maximize tissue preservation. The authors applied this technique to 2 patients with cavernomas in eloquent locations with excellent outcomes.

 

Cotton-clipping and cotton-augmentation for aneurysms

cotton-clipping-and-cotton-augmentation-for-aneurysms

J Neurosurg 125:720–729, 2016

To address the challenges of microsurgically treating broad-based, frail, and otherwise complex aneurysms that are not amenable to direct clipping, alternative techniques have been developed. One such technique is to use cotton to augment clipping (“cotton-clipping” technique), which is also used to manage intraoperative aneurysm neck rupture, and another is to reinforce unclippable segments or remnants of aneurysm necks with cotton (“cottonaugmentation” technique). This study reviews the natural history of patients with aneurysms treated with cotton-clipping and cotton-augmentation techniques.

Methods The authors queried a database consisting of all patients with aneurysms treated at Barrow Neurological Institute in Phoenix, Arizona, between January 1, 2004, and December 31, 2014, to identify cases in which cotton-clipping or cotton-augmentation strategies had been used. Management was categorized as the cotton-clipping technique if cotton was used within the blades of the aneurysm clip and as the cotton-clipping technique if cotton was used to reinforce aneurysms or portions of the aneurysm that were unclippable due to the presence of perforators, atherosclerosis, or residual aneurysms. Data were reviewed to assess patient outcomes and annual rates of aneurysm recurrence or hemorrhage after the initial procedures were performed.

Results The authors identified 60 aneurysms treated with these techniques in 57 patients (18 patients with ruptured aneurysms and 39 patients with unruptured aneurysms) whose mean age was 53.1 years (median 55 years; range 24–72 years). Twenty-three aneurysms (11 cases of subarachnoid hemorrhage) were treated using cotton-clipping and 37 with cotton-augmentation techniques (7 cases of subarachnoid hemorrhage). In total, 18 patients presented with subarachnoid hemorrhage. The mean Glasgow Outcome Scale (GOS) score at the time of discharge was 4.4. At a mean follow-up of 60.9 ± 35.6 months (median 70 months; range 10–126 months), the mean GOS score at last follow-up was 4.8. The total number of patient follow-up years was 289.4. During the follow-up period, none of the cotton-clipped aneurysms increased in size, changed in configuration, or rebled. None of the patients experienced early rebleeding. The annual hemorrhage rate for aneurysms treated with cotton-augmentation was 0.52% and the recurrence rate was 1.03% per year. For all patients in the study, the overall risk of hemorrhage was 0.35% per year and the annual recurrence rate was 0.69%.

Conclusions Cotton-clipping is an effective and durable treatment strategy for intraoperative aneurysm rupture and for management of broad-based aneurysms. Cotton-augmentation can be safely used to manage unclippable or partially clipped intracranial aneurysms and affords protection from early aneurysm re-rupture and a relatively low rate of late rehemorrhage.

A new comorbidities index for risk stratification for treatment of unruptured cerebral aneurysms

Aneurysm surgery

J Neurosurg 125:713–719, 2016

Comorbidities have an impact on risk stratification for outcomes in analyses of large patient databases. Although the Charlson Comorbidity Index (CCI) and the Elixhauser Comorbidity Index (ECI) are the most commonly used comorbidity indexes, these have not been validated for patients with unruptured cerebral aneurysms; therefore, the authors created a comorbidity index specific to these patients.

Methods The authors extracted all records involving unruptured cerebral aneurysms treated with clipping, coiling, or both from the Nationwide Inpatient Sample (2002–2010). They assessed the effect of 37 variables on poor outcome and used the results to create a risk score for these patients. The authors used a validation data set and bootstrapping to evaluate the new index and compared it to CCI and ECI in prediction of poor outcome, mortality, length of stay, and hospital charges.

Results The index assigns integer values (-2 to 7) to 20 comorbidities: neurological disorder, renal insufficiency, gastrointestinal bleeding, paralysis, acute myocardial infarction, electrolyte disorder, weight loss, metastatic cancer, drug abuse, arrhythmia, coagulopathy, cerebrovascular accident, psychosis, alcoholism, perivascular disease, valvular disease, tobacco use, hypothyroidism, depression, and hypercholesterolemia. Values are summed to determine a patient’s risk score. The new index was better at predicting poor outcome than CCI or ECI (area under the receiver operating characteristic curve [AUC] 0.814 [95% CI 0.798–0.830], vs 0.694 and 0.712, respectively, for the other indices), and it was also better at predicting mortality (AUC 0.775 [95% CI 0.754–0.792], vs 0.635 and 0.657, respectively, for CCI and ECI).

Conclusions This new comorbidity index outperforms the CCI and ECI in predicting poor outcome, mortality, length of stay, and total charges for patients with unruptured cerebral aneurysm. Reevaluation of other patient cohorts is warranted to determine the impact of more accurate patient stratification.

Hemodynamic and morphological characteristics of unruptured posterior communicating artery aneurysms with oculomotor nerve palsy

Hemodynamic and morphological characteristics of unruptured posterior communicating artery aneurysms with oculomotor nerve palsy

J Neurosurg 125:264–268, 2016

Unruptured posterior communicating artery (PCoA) aneurysms with oculomotor nerve palsy (ONP) have a very high risk of rupture. This study investigated the hemodynamic and morphological characteristics of intracranial aneurysms with high rupture risk by analyzing PCoA aneurysms with ONP.

Methods: Fourteen unruptured PCoA aneurysms with ONP, 33 ruptured PCoA aneurysms, and 21 asymptomatic unruptured PCoA aneurysms were included in this study. The clinical, morphological, and hemodynamic characteristics were compared among the different groups.

Results: The clinical characteristics did not differ among the 3 groups (p > 0.05), whereas the morphological and hemodynamic analyses showed that size, aspect ratio, size ratio, undulation index, nonsphericity index, ellipticity index, normalized wall shear stress (WSS), and percentage of low WSS area differed significantly (p < 0.05) among the 3 groups. Furthermore, multiple comparisons revealed that these parameters differed significantly between the ONP group and the asymptomatic unruptured group and between the ruptured group and the asymptomatic unruptured group, except for size, which differed significantly only between the ONP group and the asymptomatic unruptured group (p = 0.0005). No morphological or hemodynamic parameters differed between the ONP group and the ruptured group.

Conclusions: Unruptured PCoA aneurysms with ONP demonstrated a distinctive morphological-hemodynamic pattern that was significantly different compared with asymptomatic unruptured PCoA aneurysms and was similar to ruptured PCoA aneurysms. The larger size, more irregular shape, and lower WSS might be related to the high rupture risk of PCoA aneurysms.

Early whole-brain CT perfusion for detection of patients at risk for delayed cerebral ischemia after subarachnoid hemorrhage

Early whole-brain CT perfusion for detection of patients at risk for delayed cerebral ischemia after subarachnoid hemorrhage

J Neurosurg 125:128–136, 2016

This prospective study investigated the role of whole-brain CT perfusion (CTP) studies in the identification of patients at risk for delayed ischemic neurological deficits (DIND) and of tissue at risk for delayed cerebral infarction (DCI).

Methods: Forty-three patients with aneurysmal subarachnoid hemorrhage (aSAH) were included in this study. A CTP study was routinely performed in the early phase (Day 3). The CTP study was repeated in cases of transcranial Doppler sonography (TCD)–measured blood flow velocity (BFV) increase of > 50 cm/sec within 24 hours and/or on Day 7 in patients who were intubated/sedated.

Results: Early CTP studies revealed perfusion deficits in 14 patients, of whom 10 patients (72%) developed DIND, and 6 of these 10 patients (60%) had DCI. Three of the 14 patients (21%) with early perfusion deficits developed DCI without having had DIND, and the remaining patient (7%) had neither DIND nor DCI. There was a statistically significant correlation between early perfusion deficits and occurrence of DIND and DCI (p < 0.0001). A repeated CTP was performed in 8 patients with a TCD–measured BFV increase > 50 cm/sec within 24 hours, revealing a perfusion deficit in 3 of them (38%). Two of the 3 patients (67%) developed DCI without preceding DIND and 1 patient (33%) had DIND without DCI. In 4 of the 7 patients (57%) who were sedated and/or comatose, additional CTP studies on Day 7 showed perfusion deficits. All 4 patients developed DCI.

Conclusions: Whole-brain CTP on Day 3 after aSAH allows early and reliable identification of patients at risk for DIND and tissue at risk for DCI. Additional CTP investigations, guided by TCD–measured BFV increase or persisting coma, do not contribute to information gain.

Dural arteriovenous fistula–induced thalamic dementia

Thalamic DAVF

J Neurosurg 124:1752–1765, 2016

Nonhemorrhagic neurological deficits are underrecognized symptoms of intracranial dural arteriovenous fistulas (dAVFs) having cortical venous drainage. These symptoms are the consequence of cortical venous hypertension and portend a clinical course with increased risk of neurological morbidity and mortality. One rarely documented and easily misinterpreted type of nonhemorrhagic neurological deficit is progressive dementia, which can result from venous hypertension in the cortex or in bilateral thalami. The latter, which is due to dAVF drainage into the deep venous system, is the less common of these 2 dementia syndromes.

Herein, the authors report 4 cases of dAVF with venous drainage into the vein of Galen causing bithalamic edema and rapidly progressive dementia. Two patients were treated successfully with endovascular embolization, and the other 2 patients were treated successfully with endovascular embolization followed by surgery. The radiographic abnormalities and presenting symptoms rapidly resolved after dAVF obliteration in all 4 cases. Detailed descriptions of these 4 cases are presented along with a critical review of 15 previously reported cases.

In our analysis of these 19 published cases, the following were emphasized: 1) the clinical and radiographic differences between dAVF-induced thalamic versus cortical dementia syndromes; 2) the differential diagnosis and necessary radiographic workup for patients presenting with a rapidly progressive thalamic dementia syndrome; 3) the frequency at which delays in diagnosis occurred and potentially dangerous and avoidable diagnostic procedures were used; and 4) the rapidity and completeness of symptom resolution following dAVF treatment.

Decompressive hemicraniectomy: predictors of functional outcome in patients with ischemic stroke

Decompressive hemicraniectomy

J Neurosurg 124:1773–1779, 2016

Patients presenting with large-territory ischemic strokes may develop intractable cerebral edema that puts them at risk of death unless intervention is performed. The purpose of this study was to identify predictors of outcome for decompressive hemicraniectomy (DH) in ischemic stroke.

Methods: The authors conducted a retrospective electronic medical record review of 1624 patients from 2006 to 2014. Subjects were screened for DH secondary to ischemic stroke involving the middle cerebral artery, internal carotid artery, or both. Ninety-five individuals were identified. Univariate and multivariate analyses were performed for an array of clinical variables in relationship to functional outcome according to the modified Rankin Scale (mRS). Clinical outcome was assessed at 90 days and at the latest follow-up (mean duration 16.5 months).

Results: The mean mRS score at 90 days and at the latest follow-up post-DH was 4. Good functional outcome was observed in 40% of patients at 90 days and in 48% of patient at the latest follow-up. The mortality rate at 90 days was 18% and at the last follow-up 20%. Univariate analysis identified a greater likelihood of poor functional outcome (mRS scores of 4–6) in patients with a history of stroke (OR 6.54 [95% CI 1.39–30.66]; p = 0.017), peak midline shift (MLS) > 10 mm (OR 3.35 [95% CI 1.33–8.47]; p = 0.011), or a history of myocardial infarction (OR 8.95 [95% CI 1.10–72.76]; p = 0.04). Multivariate analysis demonstrated elevated odds of poor functional outcome associated with a history of stroke (OR 9.14 [95% CI 1.78–47.05]; p = 0.008), MLS > 10 mm (OR 5.15 [95% CI 1.58–16.79; p = 0.007), a history of diabetes (OR 5.63 [95% CI 1.52–20.88]; p = 0.01), delayed time from onset of stroke to DH (OR 1.32 [95% CI 1.02–1.72]; p = 0.037), and evidence of pupillary dilation prior to DH (OR 4.19 [95% CI 1.06–16.51]; p = 0.04). Patients with infarction involving the dominant hemisphere had higher odds of unfavorable functional outcome at 90 days (OR 4.73 [95% CI 1.36–16.44]; p = 0.014), but at the latest follow-up, cerebral dominance was not significantly related to outcome (OR 1.63 [95% CI 0.61–4.34]; p = 0.328).

Conclusions: History of stroke, diabetes, myocardial infarction, peak MLS > 10 mm, increasing duration from onset of stroke to DH, and presence of pupillary dilation prior to intervention are associated with a worse functional outcome.

Neurosurgery Department. “La Fe” University Hospital. Valencia, Spain

Archives

Amazon Shop

The Safety and Feasibility of Image-Guided BrainPath-Mediated Trans-Sulcal Hematoma Evacuation

Haptic Virtual Reality Aneurysm Clipping

Subtemporal Approach for AICA Aneurysm Clipping

MCA Aneurysm Anatomical Classification Scheme

Blister Aneurysms of the Internal Carotid Artery

Bypass for Complex Basilar Aneurysms

Basilar Invagination and Atlanto-Axial Dislocation Video 1

Indocyanine Green Videoangiography “In Negative” Video 2

Indocyanine Green Videoangiography “In Negative” Video 1

Management of a Recurrent Coiled Giant Posterior Cerebral Artery Aneurysm

Bypass for Complex Basilar Aneurysms

Expanded Endonasal Approach for 2012 MERC

Endoscopic Endonasal Middle Clinoidectomy Video 1

Endoscopic Endonasal Middle Clinoidectomy Video 2

Neurosurgery CNS: Flash Fluorescence for MCA Bypass Video 2

Neurosurgery CNS: Flash Fluorescence for MCA Bypass Video 1

Neurosurgery CNS: Endoscopic Transventricular Lamina Terminalis Fenestration Video 2

Neurosurgery CNS: Endoscopic Transventricular Lamina Terminalis Fenestration Video 1

Neurosurgery CNS: Surgery for Giant PCOM Aneurysms Video 2

Neurosurgery CNS: Surgery for Giant PCOM Aneurysms Video 1

NeurosurgeryCNS: Endovascular-Surgical Approach to Cavernous dAVF

Neurosurgery CNS: Lateral Supraorbital Approach Applied to Anterior Clinoidal Meningiomas Video 4

Neurosurgery CNS: Lateral Supraorbital Approach Applied to Anterior Clinoidal Meningiomas Video 3

Neurosurgery CNS: Lateral Supraorbital Approach Applied to Anterior Clinoidal Meningiomas Video 2

Neurosurgery CNS: Lateral Supraorbital Approach Applied to Anterior Clinoidal Meningiomas Video 1

NeurosurgeryCNS: Surgery of AVMs in Motor Areas

NeurosurgeryCNS: The Fenestrated Yaşargil T-Bar Clip

NeurosurgeryCNS: Cotton-Clipping Technique to Repair Intraoperative Aneurysm Neck Tear Video 3

NeurosurgeryCNS: Cotton-Clipping Technique to Repair Intraoperative Aneurysm Neck Tear Video 2

NeurosurgeryCNS: Cotton-Clipping Technique to Repair Intraoperative Aneurysm Neck Tear Video 1

NeurosurgeryCNS. ‘Double-Stick Tape’ Technique for Offending Vessel Transposition in Microvascular Decompression

NeurosurgeryCNS: Advances in the Treatment and Outcome of Brain Stem Cavernous Malformation Surgery: 300 Patients

3T MRI Integrated Neuro Suite

NeurosurgeryCNS: 3D In Vivo Modeling of Vestibular Schwannomas and Surrounding Cranial Nerves Using DIT

NeurosurgeryCNS: Microsurgery for Previously Coiled Aneurysms: Experience on 81 Patients: Video 7

NeurosurgeryCNS: Microsurgery for Previously Coiled Aneurysms: Experience on 81 Patients: Video 6

NeurosurgeryCNS: Microsurgery for Previously Coiled Aneurysms: Experience on 81 Patients: Video 5

NeurosurgeryCNS: Microsurgery for Previously Coiled Aneurysms: Experience on 81 Patients: Video 4

NeurosurgeryCNS: Microsurgery for Previously Coiled Aneurysms: Experience on 81 Patients: Video 3

NeurosurgeryCNS: Microsurgery for Previously Coiled Aneurysms: Experience on 81 Patients: Video 2

NeurosurgeryCNS: Microsurgery for Previously Coiled Aneurysms: Experience on 81 Patients: Video 1

NeurosurgeryCNS: Corticotomy Closure Avoids Subdural Collections After Hemispherotomy

NeurosurgeryCNS: Operative Nuances of Side-to-Side in Situ PICA-PICA Bypass Procedure

NeurosurgeryCNS. Waterjet Dissection in Neurosurgery: An Update After 208 Procedures: Video 3

NeurosurgeryCNS. Waterjet Dissection in Neurosurgery: An Update After 208 Procedures: Video 2

NeurosurgeryCNS. Waterjet Dissection in Neurosurgery: An Update After 208 Procedures: Video 1

NeurosurgeryCNS: Fusiform Aneurysms of the Anterior Communicating Artery

NeurosurgeryCNS. Initial Clinical Experience with a High Definition Exoscope System for Microneurosurgery

NeurosurgeryCNS: Endoscopic Treatment of Arachnoid Cysts Video 2

NeurosurgeryCNS: Endoscopic Treatment of Arachnoid Cysts Video 1

NeurosurgeryCNS: Typical colloid cyst at the foramen of Monro.

NeurosurgeryCNS: Neuronavigation for Neuroendoscopic Surgery

NeurosurgeryCNS:New Aneurysm Clip System for Particularly Complex Aneurysm Surgery

NeurosurgeryCNS: AICA/PICA Anatomical Variants Penetrating the Subarcuate Fossa Dura

Craniopharyngioma Supra-Orbital Removal

NeurosurgeryCNS: Use of Flexible Hollow-Core CO2 Laser in Microsurgical Resection of CNS Lesions

NeurosurgeryCNS: Ulnar Nerve Decompression

NeurosurgeryCNS: Microvascular decompression for hemifacial spasm

NeurosurgeryCNS: ICG Videoangiography

NeurosurgeryCNS: Inappropiate aneurysm clip applications


32,508
Unique
Visitors
Powered By Google Analytics

Total views

  • 0
%d bloggers like this: