Use of Microscope-Integrated Near-Infrared Indocyanine Green Videoangiography in the Surgical Treatment of Spinal Dural Arteriovenous Fistulae

Neurosurgery 66:978-985, 2010 DOI: 10.1227/01.NEU.0000368108.94233.22

Identification and complete interruption of fistulae are essential but not always obvious during the surgical treatment of spinal dural arteriovenous fistulae (dAVFs). We examined cases in which we identified and confirmed surgical obliteration of a spinal dAVF with the aid of microscope-integrated near-infrared indocyanine green (ICG) videoangiography.

METHODS: ICG videoangiography was performed during 6 surgical interventions in which 6 intradural dorsal AVFs (type I) were interrupted. An operating microscope-integrated light source containing infrared excitation light illuminated the operating field and was used to visualize an intravenous bolus of ICG. The locations of fistulae, feeding arteries, and draining veins and documentation of occlusion of the fistulae were compared with findings on preoperative and postoperative digital subtraction angiography.

RESULTS: ICG videoangiography identified the fistulous point(s), feeding arteries, and draining veins in all 6 cases, as confirmed by immediate postoperative selective spinal angiography. In 1 case, intraoperative ICG ruled out an additional questionable fistula at a contiguous level suspected on the preoperative angiography.

CONCLUSION:Microscope-based ICG videoangiography is simple and provides real-time information about the precise location of spinal dAVFs. During spinal dAVF surgery, this technique can be useful as an independent form of angiography or as an adjunct to intraor postoperative digital subtraction angiography. Larger series are needed to determine whether use of this modality could reduce the need for immediate postoperative spinal angiography after obliteration of intradural dorsal AVFs.

Multimodality treatment of cerebral AVMs in children: a single-centre 20 years experience

Childs Nerv Syst (2010) 26:681–687.DOI 10.1007/s00381-009-1039-8

The purpose of this study was to review our experience with a multimodality treatment approach in the management of cerebral arteriovenous malformation (AVM) in children.

Methods We retrospectively analysed a consecutive series of 56 children who harboured a cerebral AVM and were treated at our institution between 1988 and 2008. During the whole treatment period, a combined treatment strategy, including microsurgery, endovascular treatment and gamma knife radiosurgery, was used.

Results Of the 56 patients (median age, 14.0; range, 3 months–18 years) reported, 36 (64.3%) were admitted after AVM rupture; of these, only one AVM (1.8%) was considered untreatable. In 30.9% (17/55) of the treated patients, a single treatment measure was sufficient to attain angiographic cure of the AVM. Among these, six patients (10.9%) had microsurgical AVM resection, four patients (7.3%) underwent endovascular treatment, and another seven patients (12.7%) underwent radiosurgical management of the AVM. The majority of the population (38/55; 69.1%) underwent combined treatment: 21 patients (38.2%) received embolisation followed by radiosurgery of the remnant nidus, ten patients (18.2%) underwent embolisation with subsequent surgical resection of the residual AVM, three patients (5.5%) had radiosurgery after incomplete surgical AVM nidus resection and another four patients (7.3%) required a combination of all three treatment modalities to achieve permanent angiographic cure of the AVM. We observed good clinical outcomes (Glasgow Outcome Scale 5 and 4) in 94.6% of the children. Complete angiographic obliteration was achieved in 93.3% of the patients treated.

Conclusion A multimodality treatment approach in children harbouring cerebral AVMs leads to excellent angiographic and clinical outcomes.

Early Ventriculoperitoneal Shunt Placement After Severe Aneurysmal Subarachnoid Hemorrhage: Role of Intraventricular Hemorrhage and Shunt Function

Neurosurgery 66:904-909, 2010 DOI: 10.1227/01.NEU.0000368385.74625.96

This study investigated the outcome of early shunt placement in patients with poor-grade subarachnoid hemorrhage and the effect of intraventricular hemorrhage (IVH) and high proteinaceous cerebrospinal fluid (CSF) on subsequent shunt performance. METHODS:This study included 33 consecutive patients with initial Fisher grade (3/4) subarachnoid hemorrhage who had undergone conversion from external ventricular drainage (EVD) to a ventriculoperitoneal (VP) shunt and whose computed tomography scan showed IVH at the time of shunt placement. Early weaning from an EVD and conversion to a VP shunt was performed irrespective of IVH or high protein content in the CSF. RESULTS: The mean interval from EVD to VP shunt placement was 6.4 days. The mean volume of IVH was 9.44 mL, and the mean value of IVH/whole ventricle volume ratio (ie, percentage of blood suspension in the CSF) was 9.81%. The mean perioperative protein level in the CSF was 149 mg/dL. During the follow-up period, 2 patients (6.1%) required VP shunt placement, and no patients experienced complications of ventriculitis or shunt-related infection. CONCLUSION: Based on our data, earlier EVD weaning and shunt placement can effectively treat subarachnoid hemorrhage–induced hydrocephalus in patients with severe subarachnoid hemorrhage. This procedure resulted in no shunt-related infections and a 6.1% revision rate. There were fewer adverse effects of IVH and protein on shunt performance. Therefore, weaning from an EVD and conversion to a permanent VP shunt need not be delayed because of IVH or proteinaceous CSF.

Acute serious rebleeding after angiographically successful coil embolization of ruptured cerebral aneurysms

Acta Neurochir (2010) 152:771–781. DOI 10.1007/s00701-009-0593-x

The present study investigated the incidence of acute rebleeding after successful coil embolization of a ruptured cerebral aneurysm, including clinical outcomes, and possible mechanisms of the events other than coil compaction and/or incomplete embolization.

Materials and methods. This study included 591 consecutive patients who presented with aneurysmal subarachnoid hemorrhage, were treated with coil embolization, and whose post-procedural angiography revealed successful embolization. Data were collected retrospectively from six patients who showed acute rebleeding despite that angiographically successful coil embolization was achieved. All clinical, radiological data and intraoperative videos were reviewed to identify causative factors which could have contributed to the occurrence of rebleeding.

Results. Incidence of acute rebleeding after successful coil embolization of ruptured cerebral aneurysm was 1.0% (6/591). In all of these six patients, complete angiographic occlusion was achieved except in one case where a small residual neck was intentionally left to avoid compromise of the parent artery. Four of the six patients showed poor clinical courses, either died or recovered with severe disability. Whenever possible, we performed an immediate craniotomy for exploration and additional clipping. Based on intraoperative findings, we hypothesized that uneven distribution of the coil masses and spontaneous resolution of thrombus among the strands of coil (inter-coil-loop thrombolysis) could be possible mechanisms of rebleeding.

Conclusion. Acute rebleeding is extremely rare, but is possible as a complication of coil embolization of a ruptured cerebral aneurysm even when a case is angiographically successful. The higher degree of morbidity and mortality is a major concern. Therefore, further investigation to discover risk factors and causative mechanisms for such a complication is sorely needed.

Usefulness of multislice computerized tomographic angiography in the postoperative evaluation of patients with clipped aneurysms

Acta Neurochir (2010) 152:793–802 DOI 10.1007/s00701-009-0465-4

The aim of our study was to evaluate the diagnostic efficacy of multislice computed tomographic angiography (MSCTA) regarding exclusion quality after aneurysm clipping.
Methods. Sixty patients (74 aneurysms) underwent microsurgical exclusion using titanium clips. The presence of aneurysm remnants on MSCTA was compared by a neuroradiologist to 2D digital subtraction angiography (DSA), which was considered as a reference examination. The contribution of 3D DSA was assessed in a subpopulation of 29 patients (35 aneurysms).
Results. With 2D DSA, six aneurysm remnants (8%) were diagnosed, and only five (7%) by MSCTA. The specificity and sensitivity were 98.5 and 83%, respectively. MSCTA failed to demonstrate one large remnant (>2 mm) because of clip artifacts (six clips). With 3D DSA six supplementary remnants were diagnosed. Two were large remnants blinded by vessel overlaps and clip artifacts. Four were small “dogeared” remnants (≤2 mm). No additional treatment was required for small remnants.
Conclusion. In the postoperative period, MSCTA was considered a useful tool to evaluate the large remnants as well as a non-invasive ulterior examination for suspected bifurcation. Nevertheless, 3D DSA is still required for an accurate evaluation of aneurysms treated by more than three clips.

Endovascular Coiling of Intracranial Aneurysms in Elderly Patients: Report of 205 Treated Aneurysms

Neurosurgery 66:714-721, 2010 DOI: 10.1227/01.NEU.0000367451.59090.D7

More elderly patients are presenting with intracranial aneurysms. Many are poor surgical candidates and often undergo endovascular treatment.

OBJECTIVE: We present our experience with embolization in elderly patients.

METHODS:We performed a retrospective review of a prospective database of elderly patients treated with coil embolization for intracranial aneurysms.

RESULTS: In a period of 16 years, 205 aneurysms were treated in 196 individuals (age range, 70–96 years; mean age, 77.3 years), including 159 females (average follow-up, 16.2 months). Ninety-seven patients presented with unruptured aneurysms, and 99 patients presented after subarachnoid hemorrhage; the diagnosis was confirmed by computed tomographic scan or lumbar puncture. Complete occlusion was achieved in 53 aneurysms (26%), with a neck remnant in 127 (62%), incomplete occlusion in 13 (6%), and 12 unsuccessful attempts. Postembolization, 89.3% of patients were neurologically intact or unchanged, whereas 8.7% had new deficits. Four patients died. By modified Rankin Scale score, at last clinical evaluation, 128 patients (65%) had a good outcome. Follow-up angiograms were available for 113 aneurysms; they revealed that 62% were unchanged, 21% were further thrombosed, and 17% had recanalized. Three aneurysms ruptured after treatment during follow-up. Rupture was not associated with incomplete occlusion or neck remnant results (P = .6). Twenty-five aneurysms required reembolization. Reembolization was not associated with new deficits or death (odds ratio, 0.56; 95% confidence interval, 0.19–1.58; P = .27).

CONCLUSION: Coil embolization of intracranial aneurysms is safe and effective in the elderly. Preembolization clinical condition strongly correlates with clinical outcome. Incomplete embolizations are not associated with a higher rerupture risk. Additional embolization does not affect the clinical results.

Non-saccular aneurysms of the supraclinoid internal carotid artery trunk causing subarachnoid hemorrhage: acute surgical treatments and review of literature

Neurosurg Rev (2010) 33:205–216. DOI 10.1007/s10143-009-0234-0

Non-saccular aneurysms (NSAs) of the internal carotid artery trunk include blood blister-like aneurysms (BBAs) and dissecting aneurysms (DAs), which are susceptible to disastrous intra- and postoperative bleeding. This study was conducted to clarify the clinical features of NSAs and the results of early bypass and trapping. Nineteen ruptured NSAs were identified in 937 patients with subarachnoid hemorrhage (SAH). The principal treatment was to trap the aneurysm following bypass surgery as soon as possible after SAH onset. Angiography revealed nine BBAs and ten DAs. Eight patients (four BBA and four DA) were treated in the chronic stage because of delayed arrival (n=3) or lack of aneurysm on initial angiography (n=3), or other reasons (n=2). The remaining 11 patients underwent early surgery using trapping after bypass, except for one BBA-type (clipped). During surgery, corresponding intraoperative findings were confirmed for each aneurysm type. There were six preoperative reruptures; five were determinant of patient outcome. In 14 patients without preoperative rerupture influencing outcome, 11 patients were independent at discharge and three patients dependent due to surgical complication. There was one case of minor intraoperative bleeding; no postoperative rerupture occurred. There was no delayed vasospasm-related deficit, although temporary symptomatic spasm occurred in three patients. Early bypass and trapping appeared to be an acceptable treatment strategy for these NSAs eliminating intra- and postoperative bleeding and not increasing a chance of delayed vasospasm.

Intraoperative computed tomography angiography with computed tomography perfusion imaging in vascular neurosurgery: feasibility of a new concept

J Neurosurg 112:722–728, 2010. (DOI: 10.3171/2009.9.JNS081255)

In vascular neurosurgery, there is a demand for intraoperative imaging of blood vessels as well as for rapid information about critical impairment of brain perfusion. This study was conducted to analyze the feasibility of intraoperative CT angiography and brain perfusion mapping using an up-to-date multislice CT scanner in a prospective pilot series.

Methods. Ten patients with unruptured aneurysms underwent intraoperative scanning with a 40-slice slidinggantry CT scanner. Multimodal CT acquisition was obtained in 8 patients consisting of dynamic perfusion CT (PCT) scanning followed by intracranial CT angiography. Two of these patients underwent CT angiography and PCT 2 times in 1 session as a control after repositioning cerebral aneurysm clips. In another 2 patients, CT angiography was performed alone. The quality of all imaging obtained was assessed in a blinded consensus reading performed by an experienced neurosurgeon and an experienced neuroradiologist. A 6-point scoring system ranging from excellent to insufficient was used for quality evaluation of PCT and CT angiography.

Results. In 9 of 10 PCT data sets, the quality was rated excellent or good. In the remaining case, the quality was rated insufficient for diagnostic evaluation due to major streak artifacts induced by the titanium pins of the head clamp. In this particular case, the quality of the related CT angiography was rated good and sufficient for intraoperative decision making. The quality of all 12 CT angiography data sets was rated excellent or good. In 1 patient with an anterior communicating artery aneurysm, PCT scanning led to a repositioning of the clip because of an ischemic pattern of the perfusion parameter maps due to clip stenosis of an artery. The subsequent PCT scan obtained in this patient revealed an improved perfusion of the related vascular territory, and follow-up MR imaging showed only minor ischemia of the anterior cerebral artery territory.

Conclusions. Intraoperative CT angiography and PCT scanning were shown to be feasible with short acquisition time, little interference with the surgical workflow, and very good diagnostic imaging quality. Thus, these modalities might be very helpful in vascular neurosurgery. Having demonstrated their feasibility, the impact of these methods on patients’ outcomes has now to be analyzed prospectively in a larger series.

Which Variables Help Explain the Poor Health-Related Quality of Life After Subarachnoid Hemorrhage? A Meta-analysis

Neurosurgery 66:772-783, 2010. DOI: 10.1227/01.NEU.0000367548.63164.B2
Patients with subarachnoid hemorrhage (SAH) are younger than typical stroke patients. Poor psychosocial outcome after SAH therefore leads to a disproportionately high impact on patients, relatives, and society. Addressing this problem requires an understanding of what causes poor psychosocial outcome. Numerous studies have examined potential predictors but produced conflicting results. We aim to resolve this uncertainty about the potential value of individual predictors by conducting a meta-analysis. This approach allows us to quantitatively combine the findings from all relevant studies to identify promising predictors of psychosocial outcome and determine the strength with which those predictors are associated with measures of psychosocial health.
METHODS: Psychosocial health was measured by health-related quality of life (HRQOL). We included in our analysis those predictors that were most frequently examined in this context, namely patient age, sex, neurologic state at the time of hospital admission, bleed severity, physical disability, cognitive impairment, and time between ictus and psychosocial assessment.
RESULTS: Only 1 of the traditional variables, physical disability, had any notable affect on HRQOL. Therefore, the cause of most HRQOL impairment after SAH remains unknown. The situation is even worse for mental HRQOL, an area that is often significantly affected in SAH patients. Here, 90% of the variance remains unexplained by traditional predictors.
CONCLUSION: Studies need to turn to new factors to account for poor patient outcome.

A Supplementary Grading Scale for Selecting Patients With Brain Arteriovenous Malformations for Surgery

Neurosurgery 66:702-713, 2010. DOI: 10.1227/01.NEU.0000367555.16733.E1

Patient age, hemorrhagic presentation, nidal diffuseness, and deep perforating artery supply are important factors when selecting patients with brain arteriovenous malformations (AVMs) for surgery.

OBJECTIVE: We hypothesized that these factors outside of the Spetzler-Martin grading system could be combined into a simple, supplementary grading system that would accurately predict neurologic outcome and refine patient selection.

METHODS: A consecutive, single-surgeon series of 300 patients with AVMs treated microsurgically was analyzed in terms of change between preoperative and final postoperative modified Rankin Scale scores. Three different multivariable logistic models (full, Spetzler- Martin, and supplementary models) were constructed to test the association of combined predictor variables with the change in modified Rankin Scale score. A simplified supplementary grading system was developed from the data with points assigned according to each variable and added together for a supplementary AVM grade.

RESULTS: Predictive accuracy was highest for the full multivariable model (receiver operating characteristic curve area, 0.78), followed by the supplementary model (0.73), and least for the Spetzler-Martin model (0.66). Predictive accuracy of the simplified supplementary grade was significantly better than that of the Spetzler-Martin grade (P = .042), with receiver operating characteristic curve areas of 0.73 and 0.65, respectively.

CONCLUSION: This new AVM grading system supplements rather than replaces the wellestablished Spetzler-Martin grading system and is a better predictor of neurologic outcomes after AVM surgery. The supplementary grading scale has high predictive accuracy on its own and stratifies surgical risk more evenly. The supplementary grading system is easily applicable at the bedside, where it is intended to improve preoperative risk prediction and patient selection for surgery.

Exacerbation of Perihematomal Edema and Sterile Meningitis With Intraventricular Administration of Tissue Plasminogen Activator in Patients With Intracerebral Hemorrhage

Neurosurgery 66:631-638, 2010. DOI: 10.1227/01.NEU.0000367634.89384.4B

Intraventricular hemorrhage (IVH) is associated with a poor outcome. External ventricular drainage together with clot lysis through intrathecal tissue plasminogen activator (IT-tPA) has been proposed as a promising therapy. However, recent experimental work has implicated tissue plasminogen activator (tPA) in the pathogenesis of cerebral edema.

METHODS: We reviewed the records of all patients with IVH caused by primary supratentorial intracerebral hemorrhage who underwent external ventricular drainage without surgical evacuation between January 2001 and June 2008. Of these 30 patients, we identified 13 who received IT-tPA. The remaining 17 patients served as controls. Hemorrhage, edema volume, and IVH score were determined on admission and by follow-up computed tomographic scans for 96 hours after admission. Discharge outcome was evaluated using the modified Rankin Scale.

RESULTS: There were no significant differences between the treatment and controls in terms of age, Glasgow Coma Scale score, Graeb and LeRoux IVH scores, or intracerebral hemorrhage volume on admission. IT-tPA resulted in more rapid clearance of IVH as determined by the 96-hour decrease in both the Graeb IVH score (tPA, 3.00 ± .55; control, 1.00 ± 0.57; P = .05) and the LeRoux IVH score (tPA, 6.2 ± 0.80; control, 2.25 ± 1.32; P = .05). Patients treated with IT-tPA demonstrated significantly larger peak ratios of edema to intracerebral hemorrhage volume (1.24 ± 0.14 vs 0.70 ± 0.08 in controls; P = .002). Additionally, increased rates of sterile meningitis (46% vs 12%; P = .049) and a trend toward shunt dependence (38% vs 6%; P = .06) were observed in the tPA cohort. Nevertheless, no significant differences in outcome at discharge or length of hospital stay were observed between cohorts.

CONCLUSION: Although IT-tPA hastens the resolution of IVH, it may worsen perihematomal edema formation. Larger prospective studies are required to confirm these findings and to determine whether outcome is adversely affected by IT-tPA administration.

Saccular Intracranial Aneurysm Disease: Distribution of Site, Size, and Age Suggests Different Etiologies for Aneurysm Formation and Rupture in 316 Familial and 1454 Sporadic Eastern Finnish Patients

Neurosurgery 66:631-638, 2010. DOI: 10.1227/01.NEU.0000367634.89384.4B

Finnish saccular intracranial aneurysm (sIA) disease associates to 2q33, 8q11, and 9p21 loci and links to 19q13, Xp22, and kallikrein cluster in sIA families. Detailed phenotyping of familial and sporadic sIA disease is required for fine mapping of the Finnish sIA disease.

METHODS: Eastern Finland, which is particularly isolated genetically, is served by Kuopio University Hospital’s Department of Neurosurgery. We studied the site and size distribution of unruptured and ruptured sIAs in correlation to age and sex in 316 familial and 1454 sporadic sIA patients on first admission from 1993 to 2007.

RESULTS: The familial and sporadic aneurysmic subarachnoid hemorrhage patients had slightly different median ages (46 vs 51 years in men; 50 vs 57 years in women), different proportion of males (50% vs 42%), equal median diameter of ruptured sIAs (7 mm vs 7 mm) with no correlation to age, and equally unruptured sIAs (30% vs 28%). The unruptured sIAs were most frequent at the middle cerebral artery (MCA) bifurcation (44% vs 39%) and the anterior communicating artery (12% vs 13%), in contrast to the ruptured sIAs at the anterior communicating artery (37% vs 29%) and MCA bifurcation (29% vs 29%). The size of unruptured sIAs increased by age in the sporadic group.

CONCLUSION: The MCA bifurcation was most prone to develop unruptured sIAs, suggesting that MCA branching during the embryonic period might be involved. The different site distribution of ruptured and unruptured sIAs suggests different etiologies for sIA formation and rupture. The lack of correlation of size and age at rupture (exposure to risk factors) suggests that the size at rupture is more dependent on hemodynamic stress.

New ischaemic brain lesions on MRI after stenting or endarterectomy for symptomatic carotid stenosis: a substudy of the International Carotid Stenting Study (ICSS)

Lancet Neurol 2010; 9: 353–62. DOI:10.1016/S1474- 4422(10)70057-0

The International Carotid Stenting Study (ICSS) of stenting and endarterectomy for symptomatic carotid stenosis found a higher incidence of stroke within 30 days of stenting compared with endarterectomy. We aimed to compare the rate of ischaemic brain injury detectable on MRI between the two groups.

Methods: Patients with recently symptomatic carotid artery stenosis enrolled in ICSS were randomly assigned in a 1:1 ratio to receive carotid artery stenting or endarterectomy. Of 50 centres in ICSS, seven took part in the MRI substudy. The protocol specified that MRI was done 1–7 days before treatment, 1–3 days after treatment (post-treatment scan), and 27–33 days after treatment. Scans were analysed by two or three investigators who were masked to treatment. The primary endpoint was the presence of at least one new ischaemic brain lesion on diffusion-weighted imaging (DWI) on the post-treatment scan. Analysis was per protocol. This is a substudy of a registered trial, ISRCTN 25337470.

Findings: 231 patients (124 in the stenting group and 107 in the endarterectomy group) had MRI before and after treatment. 62 (50%) of 124 patients in the stenting group and 18 (17%) of 107 patients in the endarterectomy group had at least one new DWI lesion detected on post-treatment scans done a median of 1 day after treatment (adjusted odds ratio [OR] 5∙21, 95% CI 2∙78–9∙79; p<0∙0001). At 1 month, there were changes on fluid-attenuated inversion recovery sequences in 28 (33%) of 86 patients in the stenting group and six (8%) of 75 in the endarterectomy group (adjusted OR 5·93, 95% CI 2·25–15·62; p=0·0003). In patients treated at a centre with a policy of using cerebral protection devices, 37 (73%) of 51 in the stenting group and eight (17%) of 46 in the endarterectomy group had at least one new DWI lesion on post-treatment scans (adjusted OR 12·20, 95% CI 4·53–32·84), whereas in those treated at a centre with a policy of unprotected stenting, 25 (34%) of 73 patients in the stenting group and ten (16%) of 61 in the endarterectomy group had new lesions on DWI (adjusted OR 2·70, 1·16–6·24; interaction p=0·019).

Interpretation: About three times more patients in the stenting group than in the endarterectomy group had new ischaemic lesions on DWI on post-treatment scans. The difference in clinical stroke risk in ICSS is therefore unlikely to have been caused by ascertainment bias. Protection devices did not seem to be effective in preventing cerebral ischaemia during stenting. DWI might serve as a surrogate outcome measure in future trials of carotid interventions.

Randomized, double-blind, placebo-controlled, pilot trial of high-dose methylprednisolone in aneurysmal subarachnoid hemorrhage

J Neurosurg 112:681–688, 2010. DOI: 10.3171/2009.4.JNS081377

The object of this study was to determine the efficacy of methylprednisolone in reducing symptomatic vasospasm and poor outcomes after subarachnoid hemorrhage (SAH).

Methods. Ninety-five patients with proven SAH were recruited into a double-blind, placebo-controlled, random- ized trial. Starting within 6 hours after angiographic diagnosis of aneurysm rupture, placebo or methylprednisolone, 16 mg/kg, was administered intravenously every day for 3 days to 46 and 49 patients, respectively. Deterioration, defined as development of a focal sign or decrease of more than 1 point on the Glasgow Coma Scale for more than 6 hours, was investigated by using clinical criteria and transcranial Doppler ultrasonography, cerebral angiography, or CT when appropriate. The end points were incidence of symptomatic vasospasm (delayed ischemic neurological deficits associated with angiographic arterial narrowing or accelerated flow on Doppler ultrasonography, or both) and outcome 1 year after entry into the study according to a simplified Rankin scale (Functional Outcome Scale [FOS]) in living patients and the Glasgow Outcome Scale in all patients included.

Results. All episodes of deterioration and all living patients with a 1-year outcome were assessed by a review committee. In patients treated with methylprednisolone, the incidence of symptomatic vasospasm was 26.5% com- pared with 26.0% in those given placebo. Poor outcomes according to FOS were significantly reduced in the Meth- ylprednisolone Group at 1 year of follow-up; the risk difference was 19.3% (95% CI 0.5–37.9%). The outcome was poor in 15% (6/40) of patients in the Methylprednisolone Group versus 34% (13/38) in the Placebo Group.

Conclusions. A safe and simple treatment with methylprednisolone did not reduce the incidence of symptomatic vasospasm but improved ability and functional outcome at 1 year after SAH.

Monitoring intracranial pressure in patients with malignant middle cerebral artery infarction: is it useful?

J Neurosurg 112:648–657, 2010. DOI: 10.3171/2009.7.JNS081677

Intracranial pressure (ICP) monitoring is increasingly used in the treatment of patients with malignant middle cerebral artery (MCA) infarction. However, neurological deterioration may exist independent from intracranial hypertension. This study aimed to present the findings of continuous ICP monitoring in a cohort of patients with malignant MCA infarction and to correlate these findings with clinical and radiological features.

Methods. The authors studied a prospective cohort of 25 patients with malignant MCA infarction consecutively admitted to the neurotrauma intensive care unit of the Vall d’Hebron University Hospital between March 2002 and September 2006. The patients were treated using a combined protocol of initial moderate hypothermia and hemi-craniectomy. The latter was performed when patients showed a midline shift (MLS) ≥ 5 mm or ICP > 20 mm Hg. Six patients had an MLS ≥ 5 mm on the first CT scan and underwent surgery without prior ICP monitoring. This study focuses on the subgroup of 19 patients who underwent intraparenchymatous ICP monitoring before surgery.

Results. Intracranial pressure readings were evaluated and correlated with pupillary abnormalities, MLS, and ischemic tissue volume. In 12 of the 19 patients, ICP values were always ≤ 20 mm Hg, despite a mean (± SD) MLS of 6.7 ± 2 mm and a mean ischemic tissue volume of 241.3 ± 83 cm3. In 2 patients with anisocoria, ICP values were also normal.

Conclusions. In patients with a malignant MCA infarction, pupillary abnormalities and severe brainstem compression may be present despite normal ICP values. Therefore, continuous ICP monitoring cannot substitute for close clinical and radiological follow-up in the management of these patients.

Outcome correlates with blood distribution in subarachnoid hemorrhage of unknown origin

Acta Neurochir (2010) 152:417–42.DOI10.1007/s00701-009-0525-9

Between 15 and 30 % of patients with subarachnoid hemorrhage (SAH) have no bleeding source and usually have a benign clinical course and outcome. The objectives of this study were to classify the pattern of blood distribution on initial computed tomography (CT) and to correlate it with clinical outcome in aneurysmal (ASAH) and SAH of unknown origin (SAHuO).

Methods We reviewed 112 CTs of SAHuO and 104 CTs of ASAH patients. Blood distribution was classified according to a new grading system (type 0–4) and correlated to Hunt and Hess (H&H) grade and modified Rankin scores (MRS) at short- and long-term follow-up.

Results Fifty percent of 112 SAHuO patients were classified as type 0 (no visible blood on CT) or 1 (blood restricted to prepontine cisterns). Most ASAH patients presented with bleeding into the lateral Sylvian fissure (66%; type 3) or with intracerebral hemorrhage (27%; type 4) whereas types 0 and 1 were not observed. SAHuO patients were in better clinical condition on admission than ASAH patients (p<0.0001). H&H grades of SAHuO patients correlated with the amount of subarachnoid blood according to the new classification (p=0.004). Short-term outcome was obtained from 100% and long-term outcome from 95% patients (follow-up 29±31 months). Short- and long-term MRS correlated with blood distribution in SAHuO patients (p=0.012) and was significantly better than in ASAH patients (p<0.0001). No correlation was observed between blood distribution, H&H grade, and short- and long-term outcome in aneurysmal patients.

Conclusions In SAH of unknown origin, a new classification allows to predict outcome based on the extent of blood on CT.

How Safe Is Arteriovenous Malformation Surgery? A Prospective, Observational Study of Surgery As First-Line Treatment for Brain Arteriovenous Malformations

DOI: 10.1227/01.NEU.0000365518.47684.98

OBJECTIVES: Existing studies reporting the risk of surgery for brain arteriovenous malformations (AVMs) are often biased by the exclusion of patients not offered surgery. In this study, we examine the risk of surgery, including cases excluded from surgery because of the high surgical risk.
METHODS: Data were collected on 640 consecutively enrolled AVMs in a database that included all patients not considered for surgery.
RESULTS: Patients with Spetzler-Martin grade 1 to 2 AVMs (n = 296) were treated with a surgical risk of 0.7% (95% confidence interval [CI], 0%-3%); patients with Spetzler-Martin grade 3 to 4 AVMs in noneloquent cortex (n = 65) were treated with a surgical risk of 17% (95% CI, 10%-28%). Patients with Spetzler-Martin grade 3 to 5 AVMs in eloquent cortex (n = 168) were treated with a surgical risk of 21% (95% CI, 15%-28%). However, because 14% of patients in this series with similar AVMs were refused surgery because of perceived surgical risk, these results are not generalizable to the population of patients with similar AVMs.
CONCLUSION: The results of this series suggest that it is reasonable to offer surgery as a preferred treatment option for Spetzler-Martin grade 1 to 2 AVMs. This study also reinforces the predictive value of the Spetzler-Martin grading system, with some caveats.

Cognitive Functioning and Health-Related Quality of Life 1 Year After Aneurysmal Subarachnoid Hemorrhage in Preoperative Comatose Patients (Hunt and Hess Grade V Patients)

DOI: 10.1227/01.NEU.0000365364.87303.AC

OBJECTIVE: The objective of this study was to determine cognitive functioning and health related quality of life one year after aneurysmal subarachnoid hemorrhage in preoperative comatose patients.

METHODS: Patients were investigated for one year using a comprehensive neuropsychological test battery and two HRQOL questionnaires.

RESULTS: Thirty-five of 70 patients survived the bleed, and 26 underwent neuropsychological testing. Two distinct patient groups emerged; one (n = 14) with good cognitive function, and the other (n = 12) with poor cognitive and motor function. Patients performing poorly were older (p = 0.04), had fewer years of education, (p = 0.005) larger preoperative ventricular scores, and were more often shunted (p = 0.02). There were also differences between the two groups in the Glasgow Outcome Scale (p = 0.001), modified Rankin Scale (p = 0.001), and employment status. HRQOL was more reduced in patients with poor cognitive function.

CONCLUSION: A high fraction of survivors among preoperative comatose aneurysmal SAH patients (Hunt and Hess grade V patients) recover to a good physical and cognitive function.

Preliminary Personal Experiences With the Application of Near-Infrared Indocyanine Green Videoangiography in Extracranial Vertebral Artery Surgery

INTRODUCTION:We evaluated the feasibility, usefulness, and limitations of near-infrared indocyanine green (ICG) videoangiography during procedures involving the extracranial vertebral artery (VA).

METHODS: Nine patients (2 women, 7 men; mean age, 55 years) were evaluated at 2 neurosurgical centers. Near-infrared ICG videoangiography was applied during transposition and rerouting of the first segment of VA (V1; n = 6) and during resection of neurinomas near the second (V2; n = 1) and third (V3; n = 2) segments of VA.

RESULTS: Early after ICG injection, V1 fluoresced homogenously. The fluorescence of V2 and V3 varied. Without extrinsic compression, these segments appeared as noncontiguous hot spots because the VA runs freely in a periosteal sheath surrounded by a venous plexus that attenuates the fluorescent light. Hot spots corresponded to areas where the artery neared the surface. With extrinsic compression, VA enhanced homogenously because it was pushed against the periosteal layer. During the late phase, the V1 signal was attenuated, whereas the venous plexus surrounding V2 and V3 enhanced homogeneously, thereby masking the VA itself. Near-infrared ICG videoangiography helped to confirm VA patency during transposition and rerouting but was not helpful during VA exposure because the periosteal sheath must already be exposed to detect the VA or its surrounding plexus. After exposure, videoangiography can help to determine the position of the VA within its periosteal sheath.

CONCLUSION: Videoangiography can be used to provide information about the patency of the VA and its location within the periosteal sheath to prevent injury during resection of tumor adherent to the periosteal sheath.

Supracerebellar Infratentorial Approach to Cavernous Malformations of the Brainstem: Surgical Variants and Clinical Experience With 45 Patients

Neurosurgery 66:389-399, 2010. DOI: 10.1227/01.NEU.0000363702.67016.5D

OBJECTIVE: The supracerebellar infratentorial (SCIT) approach can be performed at the midline (median variant), lateral to the midline (paramedian variant), or at the level of the angle formed by the transverse and sigmoid sinuses (extreme lateral variant). We analyzed our experience with SCIT approaches for the surgical treatment of cavernous malformations of the brainstem (CMBs).

METHODS: Demographic, clinical, radiologic, and surgical data from 45 patients (20 males and 25 females; mean age, 36.2 years) with CMBs surgically removed through SCIT approaches were reviewed retrospectively. Anatomic information was explored using cadaver head dissection.

RESULTS: Twenty-three lesions were in the midbrain, 3 were at the midbrain and extended to the thalamus, 9 were at the pontomesencephalic junction, and 10 were in the upper pons. All patients presented with hemorrhage. The median variant was used in 13 patients, the paramedian variant in 9, and the extreme lateral variant in 23. Intraoperatively, all CMBs were associated with a developmental venous anomaly. At last follow-up, 88% of the patients were the same or better. After a mean follow-up of 20 months, their mean Glasgow Outcome Scale score was 4.1.

CONCLUSION: SCIT approaches provide excellent exposure to CMBs located at the posterior incisural space, not only in the midline but also in the posterolateral surface of the upper pons and midbrain. Careful preoperative planning and neuronavigational assistance are needed to determine the best angle of attack and trajectory for SCIT approaches. Refined microsurgical techniques are paramount to achieve safe surgical removal of CMBs with good outcomes.