Brain invasion in meningiomas: does surgical sampling impact specimen characteristics and histology?

Brain invasion (BI) is a new criterion for atypia in meningiomas and therefore potentially impacts adjuvant treatment. However, it remains unclear whether surgical practice and specimen characteristics influence histopathological analyses and the accuracy of detecting BI. Tumor location, specimen characteristics, and rates of BI were compared in meningioma samples obtained from 2938 surgeries in different neurosurgical departments but diagnosed in a single neuropathological institute. Non-skull base tumor location was associated with CNS tissue on the microscopic slides (OR 1.45; p < .001), increasing specimen weight (OR 1.01; p < .001), and remaining tissue not subjected to neuropathological analyses (OR 2.18; p < .001) but not with BI (OR 1.29; p = .199). Specimen weight, rates of residual tissue not subjected to histopathological analyses, of BI and of brain tissue, on the microscopic slides differed among the neurosurgical centers (p < .001, each). Frequency of BI was increased in one department (OR 2.07; p = .002) and tended to be lower in another (OR .61; p = .088). The same centers displayed the highest and lowest rates of brain tissue in the specimen, respectively (p < .001). Moreover, the correlation of BI with the neurosurgical center was not confirmed when only analyzing specimen with evidence of brain tissue in microscopic analyses (p = .223). Detection of BI was not correlated with the intraoperative use of CUSA in subgroup analyses. Rates of brain invasion in neuropathological analyses are not associated with tumor location but differ among some neurosurgical centers. Evidence raises that surgical nuances impact specimen characteristics and therefore the accuracy of the detection of BI.

The adjustable proGAV shunt: a prospective safety and reliability multicenter study.

OBJECTIVE: To evaluate the reliability of the gravitation-assisted adjustable proGAV shunt system with a prospective multicenter study conducted in 10 German hospitals. METHODS: Enrollment for this observational study began in April 2005 and concluded in February 2006. The protocol required re-examinations 3 and 6 months postoperatively and fixed the endpoint of follow-up at 12 months after implantation. Patients with different types of adult, juvenile, and pediatric hydrocephalus were included and 165 patients were enrolled; 9 died and 12 had incomplete follow-up. RESULTS: Of the assessable 144 patients, 130 completed the protocol after 12 months, whereas 14 failed because of the need to explant the device, mainly because of infection. In 12 patients, components of the shunt, not the valve, were revised. In 65 of the 144 patients, there were 102 readjustments of the valve in 67 incidences because of underdrainage and in 35 because of overdrainage. In 1 case, readjustment was not possible. Determination of pressure level with the verification instrument was safe and corresponded to the required x-ray controls after adjustments. No unintended readjustments were noted. CONCLUSION: The proGAV is a safe and reliable device.