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Andreas Raabe, Jügen Beck, Mike Keller, Hartmuth Vatter, Michael Zimmermann and Volker Seifert

Object. Hypervolemia and hypertension therapy is routinely used for prophylaxis and treatment of symptomatic cerebral vasospasm at many institutions. Nevertheless, there is an ongoing debate about the preferred modality (hypervolemia, hypertension, or both), the degree of therapy (moderate or aggressive), and the risk or benefit of hypervolemia, moderate hypertension, and aggressive hypertension in patients following subarachnoid hemorrhage.

Methods. Monitoring data and patient charts for 45 patients were retrospectively searched to identify periods of hypervolemia, moderate hypertension, or aggressive hypertension. Measurements of central venous pressure, fluid input, urine output, arterial blood pressure, intracranial pressure, and oxygen partial pressure (PO2) in the brain tissue were extracted from periods ranging from 1 hour to 24 hours. For these periods, the change in brain tissue PO2 and the incidence of complications were analyzed.

During the 55 periods of moderate hypertension, an increase in brain tissue PO2 was found in 50 cases (90%), with complications occurring in three patients (8%). During the 25 periods of hypervolemia, an increase in brain oxygenation was found during three intervals (12%), with complications occurring in nine patients (53%). During the 10 periods of aggressive hypervolemic hypertension, an increase in brain oxygenation was found during six of the intervals (60%), with complications in five patients (50%).

Conclusions. When hypervolemia treatment is applied as in this study, it may be associated with increased risks. Note, however, that further studies are needed to determine the role of this therapeutic modality in the care of patients with cerebral vasospasm. In poor-grade patients, moderate hypertension (cerebral perfusion pressure 80–120 mm Hg) in a normovolemic, hemodiluted patient is an effective method of improving cerebral oxygenation and is associated with a lower complication rate compared with hypervolemia or aggressive hypertension therapy.

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Jürgen Beck, Andreas Raabe, Heiner Lanfermann, Joachim Berkefeld, Richard Du Mesnil De Rochemont, Friedhelm Zanella, Volker Seifert and Stefan Weidauer

Object

The aim of this study was to analyze the effects and outcome of transluminal balloon angioplasty (TBA) on brain tissue perfusion by using combined perfusion- and diffusion-weighted (PW/DW) magnetic resonance (MR) imaging in patients with cerebral vasospasm after subarachnoid hemorrhage.

Methods

Ten consecutive patients with cerebral vasospasm treated using TBA were included in this prospective study. Hemodynamically relevant vasospasm was diagnosed using a standardized PW/DW MR imaging protocol. Digital subtraction angiography was used to confirm vasospasm, and TBA was performed to dilate vasospastic arteries. The PW/DW imaging protocol was repeated after TBA. The evaluation of the passage of contrast medium after standardized application using the bolus tracking method allowed for the calculation of the time to peak (TTP) before and after TBA.

Tissue at risk was defined based on perfusion delays in individual vessel territories compared with those in reference territories. In cases with proximal focal vasospasm, TBA could dilate spastic arteries. Follow-up PW/DW MR imaging showed the disappearance of, or a decrease in, the mismatch. A TBA-induced reduction in the perfusion delay of 6.2 ± 1 seconds (mean ± standard error of the mean) to 1.5 ± 0.45 seconds resulted in the complete prevention of infarction; a reduction in the delay of 6.2 ± 2.7 to 4.1 ± 1.9 seconds resulted in the preservation of those brain tissue parts having only small infarcts in the vessel territories. Without TBA, however, the perfusion delay remained or even increased (11.1 ± 3.7 seconds), and the complete infarction of a territory occurred.

Conclusions

Angioplasty of vasospastic arteries leads to hemodynamic effects that can be quantified using PW/DW MR imaging. In cases of a severe PW/DW imaging mismatch successful TBA improved tissue perfusion and prevented cerebral infarction. The clinical significance of PW/DW MR imaging and the concept of tissue at risk is shown by cerebral infarction in vessels not accessible by TBA.

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Andreas Raabe, Jürgen Beck, Stefan Rohde, Joachim Berkefeld and Volker Seifert

Object

The aim of this study was to investigate the feasibility of integrating three-dimensional rotational angiography (3D-RA) data into a surgical navigation system and to assess its accuracy and potential clinical benefit.

Methods

The study cohort consisted of 16 patients with 16 intracranial aneurysms who had been scheduled for routine or emergency surgery. Rotational angiography data were exported using a virtual reality modeling language file format and imported into the BrainLAB VectorVision2 image-guided surgery equipment. During 3D-RA the position of the head was measured using a special headframe. The authors also determined the accuracy of 3D-RA image guidance and the clinical benefit as judged by the surgeon, including, for example, early identification of branching vessels and the aneurysm.

There was good correspondence between the 3D-RA–based navigation data and the intraoperative vascular anatomy in all cases, with a maximum error of 9° of angulation and 9° of rotation. In eight cases, the surgeon determined that the 3D-RA image guidance facilitated the surgical procedure by predicting the location of the aneurysm or the origin of a branching artery that had been covered by brain tissue and blood clots.

Conclusions

The integration of 3D-RA into surgical navigation systems is feasible, but it currently requires a new perspective-registration technique. The intraoperative 3D view provides useful information about the vascular anatomy and may improve the quality of aneurysm surgery in selected cases.

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Hartmut Vatter, Juergen Konczalla, Stefan Weidauer, Christine Preibisch, Michael Zimmermann, Andreas Raabe and Volker Seifert

Object

The key role in the development of cerebral vasospasm after subarachnoid hemorrhage (SAH) is increasingly assigned to endothelin (ET)-1. Constriction of the cerebrovasculature by ET-1 is mainly mediated by the ETA receptor but is putatively altered during the development of cerebral vasospasm. Therefore, the aim in the present study was to characterize these alterations, with the emphasis on the ETA receptor.

Methods

Cerebral vasospasm was induced using the rat double-hemorrhage model and proven by perfusion weighted magnetic resonance imaging. Rats were killed on Day 5 after SAH, and immunohistochemical staining for ETA receptors was performed. The isometric force of basilar artery ring segments with (E+, control group) and without (E−, SAH group) endothelial function was measured. Concentration effect curves (CECs) for ET-1 were constructed by cumulative application in the absence and presence of the selective ETA receptor antagonist clazosentan (10−8 or 10−7 M).

Results

The CEC for E+ segments was significantly shifted to the left after SAH by a factor of 3.7, whereas maximum contraction was unchanged. In E− segments, the CECs were not shifted during cerebral vasospasm but the maximum contraction was significantly enhanced. The inhibitory potency of clazosentan yielded a pA2 value of 8.6 ± 0.2. Immunohistochemical staining of the smooth-muscle layer showed no significant increase of ETA receptor expression, but positive staining occurred in the endothelial space after SAH.

Conclusions

The present data indicate an enhanced contractile effect of the smooth-muscle ETA receptors in cases of cerebral vasospasm. The inhibitory potency of clazosentan on this contraction is increased. Furthermore, some evidence for an ETA receptor and an endothelium-dependent vasoactive effect after SAH is provided.

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Rüdiger Gerlach, Michael Zimmermann, Elvis Hermann, Matthias Kieslich, Stefan Weidauer and Volker Seifert

✓ An intramedullary abscess of the spinal cord (IASC) represents a rare disease associated with a potentially devastating outcome. Few cases involving children suffering from an IASC have been reported in the neurosurgical literature. In the majority of the reported pediatric cases there were either congenital abnormalities, such as a dermal sinus, or signs of local infections leading to a secondary hemopoietic spread. The authors report the case of an 18-month-old girl with an extensive IASC associated with an epidermoid cyst extending from T-11 to S-2 without evidence of a dermal sinus or history of clinically apparent systemic infection. To their knowledge, this is the first case report of an IASC without a condition facilitating either direct contamination via a dermal sinus or hemopoietic spread from an infectious focus outside the central nervous system. Signs and symptoms, the clinical course, and imaging features are discussed and the relevant literature is reviewed.

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Matthias Setzer, Hartmut Vatter, Gerhard Marquardt, Volker Seifert and Frank D. Vrionis

Object

In this report, the authors describe their experience in the surgical management of spinal meningiomas at two neurosurgical centers. The results of a literature review are also presented.

Methods

Eighty consecutive patients (22 men and 58 women) with spinal meningiomas who had undergone an operation at two specific neurosurgical centers were included in this study. Functional outcomes were evaluated using univariate and multivariate analyses. A review of the literature yielded an additional 651 patients with spinal meningiomas from 9 large studies.

Results

On multivariate analysis, the variable of a poor preoperative neurological state (p < 0.02, odds ratio [OR] 13.6, 95% confidence interval [CI] 2.6–71.4) and invasion of the arachnoid/pia mater (p < 0.03, OR 15.2, 95% CI 2.5–90.4) were independent predictors of a poor outcome, whereas invasion of the arachnoid/pia (p < 0.02, OR 8.9, 95% CI 2.2–35) and duration of symptoms (p < 0.001, OR 1.12/month, 95% CI 1.05–1.2) predicted no improvement (stable or deteriorated condition). The Cox proportional hazards regression analysis showed three significant predictor variables for recurrence: invasion of the arachnoid/pia (p < 0.05; hazard ratio [HR] 1.8, 95% CI 1.2–3.6), Simpson resection grade (p < 0.012, HR 6.8, 95% CI 1.5–3.0), and histological tumor grade (Grade I; p < 0.001, HR 0.001–0.17).

Conclusions

Because of the excellent outcome of surgery for benign spinal meningiomas and the association between duration of symptoms and neurological compromise with a poor functional outcome, early operation is the treatment of choice. In cases of malignant transformation, adjuvant therapies must be considered.

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Carla S. Jung, Edward H. Oldfield, Judith Harvey-White, Michael G. Espey, Michael Zimmermann, Volker Seifert and Ryszard M. Pluta

Object

Delayed cerebral vasospasm after subarachnoid hemorrhage (SAH) may be evoked by the decreased availability of nitric oxide (NO). Increased cerebrospinal fluid (CSF) levels of asymmetric dimethyl-l-arginine (ADMA), an endogenous inhibitor of NO synthase (NOS), have been associated with the course and degree of cerebral vasospasm in a primate model of SAH. In this study, the authors sought to determine if similar changes in CSF ADMA levels are observed in patients with SAH, and whether these changes are associated with NO and NOS metabolite levels in the CSF and the presence of cerebral vasospasm.

Methods

Asymmetric dimethyl-l-arginine, l-arginine, l-citrulline, and nitrite levels were measured in CSF and serum samples collected during the 21-day period after a single aneurysmal SAH in 18 consecutive patients. Samples were also obtained in a control group consisting of seven patients with Chiari malformation Type I and five patients with spontaneous intracerebral hemorrhage without SAH. Vasospasm, defined as a greater than 11% reduction in the anterior circulation vessel diameter ratio compared with the ratio calculated from the initial arteriogram, was assessed on cerebral arteriography performed around Day 7.

Results

In 13 patients with SAH, arteriographic cerebral vasospasm developed. Cerebrospinal fluid ADMA levels in patients with SAH were higher than in those in the control group (p < 0.001). The CSF ADMA level remained unchanged in the five patients with SAH without vasospasm, but was significantly increased in patients with vasospasm after Day 3 (6.2 ± 1.7 μM) peaking during Days 7 through 9 (13.3 ± 6.7 μM; p < 0.001) and then gradually decreasing between Days 12 and 21 (8.8 ± 3.2 μM; p < 0.05). Nitrite levels in the CSF were lower in patients with vasospasm compared to patients without vasospasm (p < 0.03). Cerebrospinal fluid ADMA levels positively correlated with the degree of vasospasm (correlation coefficient [CC] = 0.88, p = 0.0001; 95% confidence interval [CI] 0.74–0.95) and negatively correlated with CSF nitrite levels (CC = −0.55; p = 0.017; 95% CI −0.81 to −0.12).

Conclusions

These results support the hypothesis that ADMA is involved in the progression of cerebral vasospasm. Asymmetric dimethyl-l-arginine and its metabolizing enzymes may be a future target for treatment of cerebral vasospasm after SAH.

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Erdem Güresir, Patrick Schuss, Hartmut Vatter, Andreas Raabe, Volker Seifert and Jürgen Beck

Object

The aim of this study was to analyze decompressive craniectomy (DC) in the setting of subarachnoid hemorrhage (SAH) with bleeding, infarction, or brain swelling as the underlying pathology in a large cohort of consecutive patients.

Methods

Decompressive craniectomy was performed in 79 of 939 patients with SAH. Patients were stratified according to the indication for DC: 1) primary brain swelling without or 2) with additional intracerebral hematoma, 3) secondary brain swelling without rebleeding or infarcts, and 4) secondary brain swelling with infarcts or 5) with rebleeding. Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months (mRS Score 0–3 favorable vs 4–6 unfavorable).

Results

Overall, 61 (77.2%) of 79 patients who did and 292 (34%) of the 860 patients who did not undergo DC had a poor clinical grade on admission (World Federation of Neurosurgical Societies Grade IV–V, p < 0.0001). A favorable outcome was attained in 21 (26.6%) of 79 patients who had undergone DC. In a comparison of favorable outcomes in patients with primary (28.0%) or secondary DC (25.5%), no difference could be found (p = 0.8). Subgroup analysis with respect to the underlying indication for DC (brain swelling vs bleeding vs infarction) revealed no difference in the rate of favorable outcomes. On multivariate analysis, acute hydrocephalus (p = 0.009) and clinical signs of herniation (p = 0.02) were significantly associated with an unfavorable outcome.

Conclusions

Based on the data in this study the authors concluded that primary as well as secondary craniectomy might be warranted, regardless of the underlying etiology (hemorrhage, infarction, or brain swelling) and admission clinical grade of the patient. The time from the onset of intractable intracranial pressure to DC seems to be crucial for a favorable outcome, even when a DC is performed late in the disease course after SAH.

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Hischam Bassiouni, Siamak Asgari, I. Erol Sandalcioglu, Volker Seifert, Dietmar Stolke and Gerhard Marquardt

Object

In this study, the authors' goal was to analyze a series of patients treated microsurgically for an anterior clinoid process (ACP) meningioma in regard to long-term functional outcome.

Methods

The authors retrospectively analyzed clinical data in a consecutive series of 106 patients who underwent microsurgical treatment for an ACP meningioma at 2 neurosurgical institutions between 1987 and 2005. The main presenting symptoms of the 84 female and 22 male patients (mean age 56 years) were visual impairment in 54% and headache in 28%. Physical examination revealed decreased visual acuity in 49% and a visual field deficit in 26%. Tumors were primarily resected via a pterional approach. Meningioma extensions invading the cavernous sinus, present in 29% of the patients, were not removed. Complete tumor resection (Simpson Grade I and II) was achieved in 59% of the cases.

Results

Postoperatively, visual acuity improved in 40%, was unchanged in 46%, and deteriorated in 14%. A new oculomotor palsy was observed in 8 patients (8%). Clinical and MR imaging data were available in 95 patients for a mean postsurgical period of 6.9 years (1.5–18 years) and revealed tumor recurrence in 10% and tumor progression after subtotal resection in 38%. Clinical deterioration on long-term follow-up consisting primarily of ophthalmological deficits was observed in 14% of the cases.

Conclusions

Acceptable functional results can be achieved after microsurgical resection of ACP meningiomas; however, long-term treatment remains challenging due to a high tumor recurrence and progression rate.

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Matthias Setzer, Frank D. Vrionis, Elvis J. Hermann, Volker Seifert and Gerhard Marquardt

Object

The authors examined a possible association between apolipoprotein E (APOE) gene polymorphism and the outcome after anterior microsurgical decompression in patients with cervical spondylotic myelopathy (CSM).

Methods

The authors conducted a prospective study of 60 consecutive patients (40 men, 20 women) with CSM who underwent anterior microsurgical decompression. The patients ranged in age from 26 to 86 years (mean 61.5 ± 14.6 years). Neurological deficits were classified according to the modified Japanese Orthopaedic Association Scale. Mean follow-up was 18.8 ± 4.6 months and APOE genotyping was carried out by isolation of DNA from venous blood samples. The APOE genotypes were determined by polymerase chain reaction followed by restriction enzyme digestion and polyacrylamide gel electrophoresis of digested fragments. Categorical variables were analyzed with the chi-square test, continuous data with the Mann-Whitney U-test, and for multiple groups with the Kruskal-Wallis H-test. A backward stepwise binary logistic regression analysis was performed to determine the effect of APOE in a multivariate model.

Results

Of the 60 patients with CSM, 35 (58.3%) improved and 25 (41.7%) did not improve or suffered deterioration (no-improvement group). In the improvement group 5 patients (8.3%) possessed the ε4 allele compared with 16 patients (26.7%) in the no-improvement group (p = 0.002, OR 3.3, 95% CI 1.7–6.1). In a multivariate model, the occurrence of the ε4 allele was a significant independent predictor for no improvement after anterior decompression and fusion (p = 0.004, OR 8.6, 95% CI 5.1–20.6).

Conclusions

The results of this study show that APOE gene polymorphism influences the short-term outcome of CSM patients after surgical decompressive and stabilizing therapy in the way that the presence of the APOE ε4 allele is an independent predictor for a no improvement. The presence of APOE may explain in part the different responses to operative therapies in patients with cervical myelopathy.