Open Access

Introduction: Vasospastic brain infarction is a devastating complication of aneurysmal subarachnoid hemorrhage (SAH). Using a probe for invasive monitoring of brain tissue oxygenation or blood flow is highly focal and may miss the site of cerebral vasospasm (CVS). Probe placement is based on the assumption that the spasm will occur either at the dependent vessel territory of the parent artery of the ruptured aneurysm or at the artery exposed to the focal thick blood clot. We investigated the likelihood of a focal monitoring sensor being placed in vasospasm or infarction territory on a hypothetical basis. Methods: From our database we retrospectively selected consecutive SAH patients with angiographically proven (day 7–14) severe CVS (narrowing of vessel lumen >50%). Depending on the aneurysm location we applied a standard protocol of probe placement to detect the most probable site of severe CVS or infarction. We analyzed whether the placement was congruent with existing CVS/infarction. Results: We analyzed 100 patients after SAH caused by aneurysms located in the following locations: MCA (n = 14), ICA (n = 30), A1CA (n = 4), AcoA or A2CA (n = 33), and VBA (n = 19). Sensor location corresponded with CVS territory in 93% of MCA, 87% of ICA, 76% of AcoA or A2CA, but only 50% of A1CA and 42% of VBA aneurysms. The focal probe was located inside the infarction territory in 95% of ICA, 89% of MCA, 78% of ACoA or A2CA, 50% of A1CA and 23% of VBA aneurysms. Conclusion: The probability that a single focal probe will be situated in the territory of severe CVS and infarction varies. It seems to be reasonably accurate for MCA and ICA aneurysms, but not for ACA or VBA aneurysms.

Background: Routine postoperative imaging (PI) following surgery for intracranial meningiomas is common practice in most neurosurgical departments. The purpose of this study was to determine the role of routine PI and its impact on clinical decision making after resection of meningioma. Methods: Patient and tumor characteristics, details of radiographic scans, symptoms and alteration of treatment courses were prospectively collected for patients undergoing removal of a supratentorial meningioma of the convexity, falx, tentorium, or lateral sphenoid wing at the authors’ institution between January 1st, 2010 and March 31st, 2012. Patients with infratentorial manifestations or meningiomas of the skull base known to be surgically difficult (e.g. olfactory groove, petroclival, medial sphenoid wing) were not included. Maximum tumor diameter was divided into groups of < 3cm (small), 3 to 6 cm (medium), and > 6 cm (large). Results: 206 patients with meningiomas were operated between January 2010 and March 2012. Of these, 113 patients met the inclusion criteria and were analyzed in this study. 83 patients (73.5%) did not present new neurological deficits, whereas 30 patients (26.5%) became clinically symptomatic. Symptomatic patients had a change in treatment after PI in 21 cases (70%), while PI was without consequence in 9 patients (30%). PI did not result in a change of treatment in all asymptomatic patients (p<0.001) irrespective of tumor size (p<0.001) or localization (p<0.001). Conclusions: PI is mandatory for clinically symptomatic patients but it is safe to waive it in clinically asymptomatic patients, even if the meningioma was large in size.

Cerebral lesions may cause degeneration and neuroplastic reorganization in both the ipsi- and the contralesional hemisphere, presumably creating an imbalance of primarily inhibitory interhemispheric influences produced via transcallosal pathways. The two hemispheres are thought to mutually hamper neuroplastic reorganization of the other hemisphere. The results of preceding degeneration and neuroplastic reorganization of white matter may be reflected by Diffusion Tensor Imaging-derived diffusivity parameters such as fractional anisotropy (FA). In this study, we applied Diffusion Tensor Imaging (DTI) to contrast the white matter status of the contralesional hemisphere of young lesioned brains with and without contralateral influences by comparing patients after hemispherotomy to those who had not undergone neurosurgery. DTI was applied to 43 healthy controls (26 females, mean age ± SD: 25.07 ± 11.33 years) and two groups of in total 51 epilepsy patients with comparable juvenile brain lesions (32 females, mean age ± SD: 25.69 ± 12.77 years) either after hemispherotomy (30 of 51 patients) or without neurosurgery (21 of 51 patients), respectively. FA values were compared between these groups using the unbiased tract-based spatial statistics approach. A voxel-wise ANCOVA controlling for age at scan yielded significant group differences in FA. A post hoc t-test between hemispherotomy patients and healthy controls revealed widespread supra-threshold voxels in the contralesional hemisphere of hemispherotomy patients indicating comparatively higher FA values (p < 0.05, FWE-corrected). The non-surgery group, in contrast, showed extensive supra-threshold voxels indicating lower FA values in the contralesional hemisphere as compared to healthy controls (p < 0.05, FWE-corrected). Whereas lower FA values are suggestive of pronounced contralesional degeneration in the non-surgery group, higher FA values in the hemispherotomy group may be interpreted as a result of preceding plastic remodeling. We conclude that, whether juvenile brain lesions are associated with contralesional degeneration or reorganization partly depends on the ipsilesional hemisphere. Contralesional reorganization as observed in hemispherotomy patients was most likely enabled by the complete neurosurgical deafferentation of the ipsilesional hemisphere and, thereby, the disinhibition of the neuroplastic potential of the contralesional hemisphere. The main argument of this study is that hemispherotomy may be seen as a major plastic stimulus and as a prerequisite for contralesional neuroplastic remodeling in patients with juvenile brain lesions.

Purpose Neuro-oncology tumor boards (NTBs) hold an established function in cancer care as multidisciplinary tumor boards. However, NTBs predominantly exist at academic and/or specialized centers. In addition to increasing centralization throughout the healthcare system, changes due to the COVID-19 pandemic have arguably resulted in advantages by conducting clinical meetings virtually. We therefore asked about the experience and acceptance of (virtualized) NTBs and their potential benefits. Methods A survey questionnaire was developed and distributed via a web-based platform. Specialized neuro-oncological centers in Germany were identified based on the number of brain tumor cases treated in the respective institution per year. Only one representative per center was invited to participate in the survey. Questions targeted the structure/organization of NTBs as well as changes due to the COVID-19 pandemic. Results A total of 65/97 institutions participated in the survey (response rate 67%). In the context of the COVID-19 pandemic, regular conventions of NTBs were maintained by the respective centers and multi-specialty participation remained high. NTBs were considered valuable by respondents in achieving the most optimal therapy for the affected patient and in maintaining/encouraging interdisciplinary debate/exchange. The settings of NTBs have been adapted during the pandemic with the increased use of virtual technology. Virtual NTBs were found to be beneficial, yet administrative support is lacking in some places. Conclusions Virtual implementation of NTBs was feasible and accepted in the centers surveyed. Therefore, successful implementation offers new avenues and may be pursued for networking between centers, thereby increasing coverage of neuro-oncology care.