Second-look surgery after pediatric brain tumor resection - Single center analysis of morbidity and volumetric efficacy.

Introduction: Postoperative residual tumor can occur for intentional or unintentional reasons. Decision-making regarding second-look surgery has to weigh molecular biology, probability of total resection and prognostic relevance against potential additional morbidity. In interdisciplinary tumor boards the neurosurgeon has to estimate risk and efficacy of second-look surgery in individual cases, based on precise data. Research question: Aim of this study was to provide such data by analyzing morbidity and volumetric efficacy of second-look surgery at a designated pediatric neuro-oncology unit. Material and methods: Children who received second-look surgery in 2007-2018 after incomplete resections were analyzed retrospectively. Measurements were performed on early postoperative magnetic resonance imaging, comparing axial diameter-based measurement as well as computer-assisted volumetric analysis. Results: 59 patients (37% of the overall cohort; 21 female; mean age: 8 â€‹± â€‹5 years) received a subtotal (n â€‹= â€‹35) or near total (n â€‹= â€‹24) resection. After interdisciplinary case review, 12 of these patients received second-look surgery mainly for residual ependymoma. This led to further tumor volume reduction in all cases (new degrees of resection: subtotal â€‹= â€‹2, near total â€‹= â€‹6, gross total â€‹= â€‹4). No new permanent morbidity or perioperative mortality was observed. Discussion and conclusion: Second-look surgery did not increase mortality and permanent morbidity, had an 8% rate of transient morbidity and achieved tumor volume reduction above 95% in 75% of selected cases, with 4 additional gross total resections. Second-look surgery is safe and effective with regard to volumetric outcome parameters even in cases with good initial resections, although the role of second-look surgery regarding oncological outcome has to be further investigated in times of personalized molecular medicine.

Neurosurgical Considerations Regarding Decompressive Craniectomy for Intracerebral Hemorrhage after SARS-CoV-2-Vaccination in Vaccine Induced Thrombotic Thrombocytopenia-VITT.

Given the ongoing global SARS-CoV-2-vaccination efforts, clinical awareness needs to be raised regarding the possibility of an increased incidence of SARS-CoV-2-vaccine-related immune-mediated thrombocytopenia in patients with intracerebral hemorrhage (ICH) secondary to cerebral sinus and vein thrombosis (CVT) requiring (emergency) neurosurgical treatment in the context of vaccine-induced immune thrombotic thrombocytopenia (VITT). Only recently, an association of vaccinations and cerebral sinus and vein thrombosis has been described. In a number of cases, neurosurgical treatment is warranted for these patients and special considerations are warranted when addressing the perioperative coagulation. We, herein, describe the past management of patients with VITT and established a literature-guided algorithm for the treatment of patients when addressing the impaired coagulation in these patients. Increasing insights addressing the pathophysiology of SARS-CoV-2-vaccine-related immune-mediated thrombocytopenia guide physicians in developing an interdisciplinary algorithm taking into account the special considerations of this disease.

Endoscopic Lavage of Extensive Chronic Subdural Hematoma in an Infant After Abusive Head Trauma: Adaptation of a Technique From Ventricular Neuroendoscopy.

Subdural fluid collections are frequently encountered in young children after non-accidental injury. In a subset of patients, these collections progress in size and ultimately require permanent drainage, which is commonly achieved with subdural-peritoneal shunts. However, excessive protein and cellular contents in the fluid are potential risk factors for shunt failure. Here, we describe the adaptation of an endoscopic lavage technique established for ventricular endoscopy with the aim of improving fluid condition prior to shunting. We present a case of subdural fluid collections secondary to non-accidental injury, where permanent shunting was required but could not be performed due to excessive protein and cellular levels in the subdural fluid despite conventional burr hole drainage. A two-month-old male infant presented with a bulging and tense fontanel, a reduced level of consciousness, bradycardia, and significant macrocephaly. Computed tomography (CT) demonstrated massive bilateral, low attenuation subdural fluid collections, reaching a diameter of 4.5 cm. Emergency burr hole washout and insertion of subdural drains was performed. Despite prolonged drainage over 10 days, the protein level remained at 544 mg/dl and the mean erythrocyte count at 6,493/µl. Continuous drainage was required to avoid clinical deterioration due to raised intracranial pressure; however, the fluid condition was still considered incompatible with permanent subdural-peritoneal shunting. We, therefore, performed an endoscopic subdural lavage with a careful evacuation of residual blood deposits. No complications were encountered. Postoperatively, mean protein level was 292 mg/dl and mean erythrocyte count was 101/µl. Endoscopic lavage could be safely performed in a case of extensive subdural low attenuation fluid collections, where conventional burr hole drainage failed to improve protein and cellular contents as a prerequisite for successful permanent shunting. We conclude that adaptation of this technique can be helpful in selected cases as an alternative procedure.

Albumin storage in neoplastic astroglial elements of gangliogliomas.

PURPOSE: Low-grade neuroepithelial tumors are frequent neuropathological findings in patients with pharmacoresistant epilepsies. Little is known regarding epileptogenic mechanisms in this group of neoplasms with gangliogliomas (GG) as the most common entity. Presence of hemosiderin deposits in GG points to impairment of the blood-brain barrier (BBB). Therefore, we hypothesized a potential role of BBB dysfunction and astrocytic albumin uptake as potential epileptogenic factor in GG. METHODS: Prussian blue staining and fluorescent double-immunohistochemistry with antibodies against albumin, GFAP, CD34 and GLUT-1 were used to analyze hemosiderin deposits and astroglial albumin accumulation in tumor and adjacent pre-existing brain tissue of GG (n=10) and several control groups, i.e. dysembryoplastic neuroepithelial tumors (DNT; n=5), focal cortical dysplasia with balloon cells (FCD IIb; n=10), astrocytomas WHO grade II (n=5) and clear renal cell carcinoma brain metastases (RCCM, n=6). RESULTS: Our results revealed strong hemosiderin deposits in GG. Intriguingly, we noted substantial albumin uptake exclusively in neoplastic glial cell components of GG and DNT, whereas no significant albumin was present in perilesional reactive astrocytes. Strikingly, we did not observe substantial albumin uptake in further controls. CONCLUSION: Glial albumin uptake was restricted to long-term epilepsy associated, vasculature-containing tumors. Intratumoural BBB dysfunction in concert with subsequent accumulation of albumin by neoplastic glial cell elements represent a new putatively epileptogenic mechanism for long-term epilepsy-associated tumors.

Cliniconeuropathologic correlations show astroglial albumin storage as a common factor in epileptogenic vascular lesions.

PURPOSE: Intracerebral vascular malformations including cavernous angiomas (CAs) and arteriovenous malformations (AVMs) are an important cause of chronic pharmacoresistant epilepsies. Little is known about the pathogenetic basis of epilepsy in patients with vascular malformations. Intracerebral deposits of iron-containing blood products have been generally regarded as responsible for the strong epileptogenic potential of CAs. Here, we have analyzed whether blood-brain barrier (BBB) dysfunction and subsequent astrocytic albumin uptake, recently described as critical trigger of focal epilepsy, represent pathogenetic factors in vascular lesion-associated epileptogenesis. METHODS: We examined the correlation between hemosiderin deposits, albumin accumulation, and several clinical characteristics in a series of 80 drug-refractory epilepsy patients with CAs or AVMs who underwent surgical resection. Analysis of clinical parameters included gender, age of seizure onset, epilepsy frequency, duration of epilepsy before surgery, and postoperative seizure outcome classification according to Engel class scale. Hemosiderin deposits in the adjacent brain tissue of the vascular lesion were semiquantitatively analyzed. Fluorescent double-immunohistochemistry using GFAP/albumin costaining was performed to study albumin extravasation. KEY FINDINGS: Our results suggest that a shorter duration of preoperative epilepsy is correlated with significantly better postsurgical outcome (p < 0.05), whereas no additional clinical or neuropathologic parameter correlated significantly with the postsurgical seizure situation. Intriguingly, we observed strong albumin immunoreactivity within the vascular lesion and in perilesional astrocytes (57.65 ± 4.05%), but not in different control groups. SIGNIFICANCE: Our present data on albumin uptake in brain tissue adjacent to AVMs and CAs suggests BBB dysfunction and accumulation of albumin within astrocytes as a new pathologic feature potentially associated with the epileptogenic mechanism for vascular lesions and provides novel therapy perspectives for antiepileptogenesis in affected patients.