Endoscopic Biopsy for Intra- and Paraventricular Tumors: Rates of Complications, Mortality, and Tumor Cell Dissemination.

BACKGROUND AND STUDY AIM: Intra- and paraventricular tumors are frequently associated with cerebrospinal fluid (CSF) pathway obstruction. Thus the aim of an endoscopic approach is to restore patency of the CSF pathways and to obtain a tumor biopsy. Because endoscopic tumor biopsy may increase tumor cell dissemination, this study sought to evaluate this risk. PATIENTS, MATERIALS, AND METHODS: Forty-four patients who underwent endoscopic biopsies for ventricular or paraventricular tumors between 1993 and 2011 were included in the study. Charts and images were reviewed retrospectively to evaluate rates of adverse events, mortality, and tumor cell dissemination. Adverse events, mortality, and tumor cell dissemination were evaluated. RESULTS: Postoperative clinical condition improved in 63.0% of patients, remained stable in 30.4%, and worsened in 6.6%. One patient (2.2%) had a postoperative thalamic stroke leading to hemiparesis and hemineglect. No procedure-related deaths occurred. Postoperative tumor cell dissemination was observed in 14.3% of patients available for follow-up. CONCLUSIONS: For patients presenting with occlusive hydrocephalus due to tumors in or adjacent to the ventricular system, endoscopic CSF diversion is the procedure of first choice. Tumor biopsy in the current study did not affect safety or efficacy.

Interobserver variability in the characterization of giant intracranial aneurysms with special emphasis on aneurysm diameter and shape.

BACKGROUND: The Giant Intracranial Aneurysm Registry is a multicenter observational trial exclusively focusing on giant intracranial aneurysms (GIA). As no data exist on the interobserver variability in the radiological description of GIA, there is some uncertainty concerning the reliability of the GIA characteristics included in the registry. We have therefore designed a study to test the interobserver variability in the description of the specific GIA characteristics that are examined in the GIA registry. METHODS: Six different raters analyzed imaging of five GIA concerning GIA location, GIA size, GIA shape, GIA thrombosis, and the presence of perianeurysmal edema. Interobserver variability was examined using intraclass correlation and Fleiss' kappa analysis. RESULTS: The intraclass correlation coefficient was 0.99 (95 % CI 0.97-1.0) for the largest GIA diameter and 0.98 (95 % CI 0.94-1.0) for the largest GIA diameter in an axial imaging slice. We found perfect interobserver agreement (Fleiss' kappa 1.00) in the characterization of GIA location and the presence of perianeurysmal edema and almost perfect interobserver agreement for GIA thrombosis (Fleiss' kappa 0.86, 95 % CI 0.63-1.00). Only moderate interobserver agreement was found in the description of GIA shape (Fleiss' kappa 0.50, 95 % CI 0.27-0.73). CONCLUSIONS: While GIA size, location, thrombosis, and the presence of perianeurysmal edema showed excellent interobserver agreement, the description of GIA shape was achieved with only moderate agreement. Data on GIA shape in multicenter studies, like the GIA registry, should therefore be discussed with caution and potentially reassessed in a centralized fashion.

Changes in volume of giant intracranial aneurysms treated by surgical strategies other than direct clipping.

BACKGROUND: Giant intracranial aneurysms (GIA) are often not eligible for direct clip occlusion. Surgical alternatives include partial clip occlusion or the placement of a cerebrovascular bypass or the combination of both. These alternative indirect strategies are expected to lead to a decrease in GIA volume over time rather than instantaneously. To examine whether this is the case, we analyzed follow-up imaging results 1 year after surgery. METHODS: We retrospectively screened the prospective GIA Registry's imaging database for anterior circulation GIA treated by surgical strategies other than direct clipping. We measured pre- and 1-year post-treatment GIA volume, lateral ventricle volume (LVV), and mid-line shift (MLS) in 19 cases. RESULTS: After a mean follow-up of 466 days (standard deviation ±171) GIA volumes decreased from 9.6 cm(3) (interquartile range (IQR) 6.1-14.1) to 4.3 cm(3) (IQR 2.9-5.7; p < 0.01). Ipsilateral LVV increased from 8.6 cm(3) (IQR 6.4-24.9) to 16.0 cm(3) (IQR 9.1-27.2; p < 0.01) while contralateral LVV increased from 10.3 cm(3) (IQR 7.3-20.1) to 11.7 cm(3) (IQR 8.2-19.4; p = 0.02). MLS changed from 0.1 mm (IQR -1.9 to 2.0) to -0.9 mm (IQR -1.8 to 0.4; p = 0.03). The decrease in GIA volume correlated with the increase in ipsilateral LVV (rs = 0.60; p = 0.01) but not with the changes in MLS (rs = 0.41; p = 0.08). CONCLUSIONS: In our patient cohort, surgical strategies other that direct clipping for the treatment of anterior circulation GIA lead to a significant decrease in GIA volume over time. The resulting decrease in mass effect was more sensitively monitored by the measurement of changes in ipsilateral LVV than changes in MLS. CLINICAL TRIAL REGISTRATION-URL: http://www.clinicaltrials.gov . Unique identifier: NCT02066493.

Perianeurysmal edema in giant intracranial aneurysms in relation to aneurysm location, size, and partial thrombosis.

OBJECT: The underlying mechanisms causing intracranial perianeurysmal edema (PAE) are still poorly understood. Since PAE is most frequently observed in giant intracranial aneurysms (GIAs), the authors designed a study to examine the occurrence of PAE in relation to the location, size, and partial thrombosis (PT) of GIAs along with the clinical impact of PAE. METHODS: Magnetic resonance imaging data for patients with a diagnosis of unruptured GIA from the international multicenter Giant Intracranial Aneurysm Registry were retrospectively analyzed with regard to location and size of the GIA, PAE volume, and the presence of PT. The occurrence of PAE was correlated to clinical findings. RESULTS: Imaging data for 69 GIAs were eligible for inclusion in this study. Perianeurysmal edema was observed in 33.3% of all cases, with the highest frequency in GIAs of the middle cerebral artery (MCA; 68.8%) and the lowest frequency in GIAs of the cavernous internal carotid artery (ICA; 0.0%). Independent predictors of PAE formation were GIA volume (OR 1.13, p = 0.02) and the occurrence of PT (OR 9.84, p = 0.04). Giant intracranial aneurysm location did not predict PAE occurrence. Giant aneurysms with PAE were larger than GIAs without PAE (p < 0.01), and GIA volume correlated with PAE volume (rs = 0.51, p = 0.01). Perianeurysmal edema had no influence on the modified Rankin Scale score (p = 0.30 or the occurrence of aphasia (p = 0.61) or hemiparesis (p = 0.82). CONCLUSIONS: Perianeurysmal edema was associated with GIA size and the presence of PT. As no PAE was observed in cavernous ICA aneurysms, even though they exerted mass effect on the brain and also displayed PT, the dura mater may serve as a barrier protecting the brain from PAE formation.

Quantifying unruptured giant intracranial aneurysms by measuring diameter and volume--a comparative analysis of 69 cases.

BACKGROUND: Intracranial aneurysms (IA) are usually quantified according to their largest diameter. However, volumetry has recently been increasingly conducted as well, especially in giant intracranial aneurysms (GIAs). Since so far the true value of GIA volumetry is unknown, we designed a trial to examine correlations between GIA diameter and volume with special focus on clinical implications. METHODS: Magnetic resonance imaging of 69 unruptured GIAs in 66 patients was retrospectively evaluated. The largest diameter and volume were measured. Also, potential associations to the patients' clinical conditions were examined. RESULTS: Comparing GIA sizes of our patient cohort produced different results depending on whether GIA diameter or volume was measured. Measuring the diameter identified posterior circulation GIAs as the largest ones (39.2 mm, IQR 37.3-48.3), while measuring the volume found GIAs of the MCA to be the largest ones (12.3 cm(3), IQR 7.2-27.8). A correlation of GIA diameter and volume was only found in anterior circulation GIAs, which were predominantly saccular in shape, but not in those of the posterior circulation, of which most were fusiform. Neither GIA diameter nor GIA volume but only GIA location was associated with neurological deficits. CONCLUSION: Diameter and volume measurements are not interchangeable modes of GIA quantification. Our data suggest that the idea of distinguishing different sizes of GIA may be clinically less relevant than examining their location, shape or mass effect.

Unusual mesencephalic developmental venous anomaly causing obstructive hydrocephalus due to aqueductal stenosis.

Developmental venous anomalies (DVAs) are benign vascular malformations that rarely become symptomatic. They are anatomical variations of the venous drainage system and most are incidentally discovered. Mechanical (obstruction and compression of cerebral and neural structures) and flow-related pathological mechanisms have been described in rare cases of symptomatic DVAs. The authors present the case of a 10-month-old boy with a mesencephalic DVA compressing the aqueduct and causing occlusive hydrocephalus. Endoscopic inspection confirmed the venous malformation causing aqueductal stenosis. The authors successfully performed endoscopic third ventriculostomy, resulting in decrease in the size of the ventricles. At the 6-month follow-up after surgery, the patient had significantly progressed in his psychomotor development. One year postsurgery the patient is doing fine, with no neurological or developmental deficits.