Neurofibromatosis type 1 (NF1) is an autosomal dominant syndrome caused by germline alteration of the NF1gene. Among various NF1-related manifestations, obstructive hydrocephalus especially in adult NF1 cases is less frequently found. We report two adult NF1 cases exhibiting obstructive hydrocephalus due to an aggressive posterior fossa tumor exhibiting pathological characteristics of pilocytic astrocytoma as NF1-related manifestations. In these two cases, we performed endoscopic third ventriculostomy (ETV) and tumor biopsy as an initial treatment. The initial pathological diagnosis of the tumor is conventional pilocytic astrocytoma. After biopsy both cases revealed rapid tumor growth, therefore, we performed tumor removal, chemotherapy, and radiation therapy during an aggressive clinical course. However, both cases revealed dismal prognosis due to the progression of the tumor in spite of successful management of hydrocephalus by an initial ETV. DNA methylation analysis revealed that the tumor of one case matched high-grade astrocytoma with piloid features (HGAP). Most central nervous system tumors developed in NF1 are less aggressive such as pilocytic astrocytoma; however, recently a few studies revealed that HGAP, which has been a newly introduced malignant tumor in the World Health Organization Classification of Tumors of the Central Nervous System, 5th edition (WHO CNS 5), rarely develops in NF1 cases. These findings suggested that HGAP might be one of the important causes of obstructive hydrocephalus in adult NF1 cases.

Giant supratentorial brain tumors (GSBTs) in children are uncommon and extremely challenging entities unique to pediatric neurosurgery. Factors such as young patient age, need for urgent intervention, intraoperative blood loss, and ongoing raised intracranial pressure symptoms are examples of difficulties faced. Recently, there has been a growing body of literature on augmented reality (AR) in adult neurosurgery. In contrast, the use of AR in pediatric neurosurgery is comparatively less. Nonetheless, we postulate that AR systems will be helpful for understanding spatial relationships of complex GSBT anatomy for preoperative planning in a timely fashion. This study describes our experience in trialing AR as a potential tool for three cases of pediatric GSBTs. Overall, the AR platform offers our neurosurgical team excellent visuospatial insights for preoperative decision-making. However, we observe that substantial time is required to set up the AR system prior to each clinical case discussion by the neurosurgical team. In congruency with existing literature, our preliminary results report that there are still obstacles that need to be addressed before the technology can be seamlessly implemented into the clinical workflow for these time-sensitive childhood brain tumors. To our knowledge, this is the first study to report the potential use of AR for complex pediatric GSBT cases.

Diffuse leptomeningeal glioneuronal tumours (DL-GNT) are rare, with an unknown incidence but fewer than 100 cases reported since 2012. The clinical presentation is non-specific, ranging from abdominal to neurological symptoms. Presently, definitive radiological criteria aren\'t established, but some features, such as nodules, characteristic extension patterns and post-contrast leptomeningeal enhancement, are found to be prominent. We present the case of a 14-year-old male with an advanced case of DL-GNT, with MRI showing all the features of what is currently thought to be the typical radiological presentation. The patient is currently undergoing treatment but remains severely handicapped by the disease.

Background Although international publications on radiosurgery have increased exponentially, reports of heterogeneous series treated with linear accelerator (LINAC) are scarce. Since most intracranial tumors are irregular in size and not spherical, LINACs (Elekta Precise®, Elekta AB, Sweden), fitted with a multi-leaf collimator, allow for precise stereotactic radiosurgery for the entire tumor. Aim To evaluate the effects of LINAC on an outpatient basis with patients diagnosed with various intracranial malignancies. Methodology A retrospective observational study of a series of cases of patients with intracranial lesions treated at the Institute of Oncology and Radiobiology using LINAC was carried out from October 2019 to May 2021 to evaluate the therapeutic results of radiosurgery in patients with intracranial tumors. Results A total of 22 lesions in 20 patients were treated with LINAC. The average age of the patients was 49.7, and the male-female ratio was 1:2. The cases consisted were mostly vestibular schwannoma (7 lesions), metastases from breast cancer (3 lesions), and tuberculum sellae meningioma (2 lesions). The prescription dose covered 99% of the planning target volume in 16 lesions (72.7%) and 100% in six lesions (27.3%) (prescription volume). In meningiomas and schwannomas, doses between 12 and 14 Gy were used, in plasmacytoma 13 Gy, in pilocytic astrocytoma 14 Gy, in cavernoma 15 Gy, in breast cancer metastasis between 18 and 20 Gy, and in lung cancer metastasis 22 Gy. When evaluating local control, 11 patients exhibited stable findings at the six-month control while 10 had partial regression, and a single patient had total regression. Minor complications such as perilesional edema, facial paresthesia, facial paralysis, and transient alopecia were observed in eight of the patients. Conclusions Patients with extra-axial, low-grade malignancy, and posterior fossa lesions were predominant in the studied population. Radiosurgery treatment is associated with good local control of the treated lesions. Complications are infrequent, mild, and predominated by perilesional edema.

Metastases to the brain from primary colorectal carcinoma are rare. Existing literature describing cranial nerve palsy from metastatic colorectal cancer is scattered. To our knowledge, we are the first to describe the combination of CN deficits V, VII, and XII as the initial presentation of colorectal malignancy. The authors present the case of a patient with no past medical history who presented with multiple cranial nerve deficits of the right trigeminal, facial, and hypoglossal nerves. MRI of the brain revealed a mass in Meckel\'s cave, which explained the involvement of the trigeminal nerve (CN V) but not the facial (CN VII) and hypoglossal (CN XII) nerves. Further workup revealed multiple cardioembolic strokes caused by nonbacterial thrombotic endocarditis (NBTE). Extensive workup for the cause of his NBTE and subsequent cerebrovascular events revealed colorectal adenocarcinoma.

Introduction Central nervous system (CNS) lesions are rare and histologically heterogenous, and carry serious potential for patient morbidity and mortality. A retrospective epidemiological review of CNS neoplasms is of great importance for future research because it can demonstrate the changes in the spectrum of CNS lesions of a population, unveil the possible associated risk factors, and indicate the potential therapeutic methods for various neoplastic and non-neoplastic lesions. Neurosurgeons have always shown an obsession with a good neuropathological diagnosis in intracranial and extracranial lesions. This obsession need not be overemphasized as it helps the clinician plan an adequate surgical/treatment strategy to optimize outcomes and minimize morbidity. Methods This study included a spectrum of 160 biopsies of patients with space-occupying lesions of the CNS during a period of two years (2019-2021). All the cases were studied and analyzed, and their histological typing/grading was done. The cases were graded and categorized according to the 2016 WHO Classification of CNS Tumors. Results Among 160 cases, the study showed a slight male preponderance of 100 (62.5%) cases. The maximum number of cases, 37 (23%) cases, was in the age group of 41-50 years. Clinically, the commonest complaints were headache and seizures. The most common location of tumor was supra-tentorial, comprising around 96 (60%) cases, of which 27 (28%) cases were located in the frontal lobe. There were four (2.5%) cases that had non-neoplastic lesions and the rest 156 (97.5%) cases had neoplastic lesions. Malignant lesions outnumbered the benign lesions, comprising of 82 (51.25%) cases. Among the neoplastic lesions, the highest cases were of astrocytoma, 48 (30.76%) cases, followed by meningioma, 42 (26.92%) cases. Also, 21 extremely rare and unusual cases were encountered. Conclusion The present study reflects the diversity of histopathological spectrum of CNS lesions in our center. In-depth studies from across various hospitals are required to have representative data on the incidence, epidemiological profile, and etiology of CNS lesions in India.

Background and aim Reoperation rate is defined as the percentage of patients returning to the operating room (OR) within 30 days of an initial craniotomy and undergoing a repeat (redo) craniotomy procedure. It is a key factor of quality-of-care assessments and has implications for outcomes, especially in oncological cases. Redo craniotomies are associated with improvement in neurological status and decreased mortality rate compared to non-surgical interventions but are associated with higher costs and risk of complications. It is important to gauge the indications and frequency of redo craniotomies as an index of quality of healthcare to improve patient outcomes. This study aimed to identify the indications, frequency, and outcomes of reoperation following an initial craniotomy in neurosurgical patients at a tertiary care hospital. Methods This retrospective cohort study was conducted at a tertiary care center in Pakistan and included all patients who underwent unplanned reoperation within 30 days of initial craniotomy from January 1, 2010, to December 31, 2017. Demographics, indications for index surgery as well as reoperation, and outcomes in the form of complications, neurological status, and mortality were collected from medical charts and analyzed. Results The study comprised 111 patients who underwent reoperations. Median age of the patients was 36 years (interquartile range {IQR}: 33 years). From a total of more than 1900 annual cases, the frequency of unplanned reoperations was 3.5%. The most common indication of unplanned reoperation based on MRI/CT was hemorrhage (40%, subdural hemorrhage was most common), followed by hydrocephalus (22%), cerebral edema (13%), and residual tumor (13%). The most common clinical reason for unplanned reoperation was a drop in Glasgow Coma Scale (GCS) (59%), whereas anisocoria was seen in 10.8% of patients. The highest mortality rate was observed in patients who were reoperated from post-operative day two to post-operative day seven (56%). Hypertension (p=0.014) and thrombocytopenia (p<0.001) showed significant associations with developing intracranial hemorrhage. Seventy-eight percent of patients showed significant improvement in their Karnofsky Performance Score (KPS) whereas 22% showed deterioration in their KPS. Conclusion The delivery of consistent quality healthcare relies on early detection and intervention in at-risk patients. Our center\'s reoperation rate is consistent with the average range among other centers globally. Hypertension, anticoagulation, and antiplatelet therapy were common risk factors for redo craniotomies within 30 days. Patients with these conditions need special care to prevent returns to the operating room. Patients also need to be monitored for hemorrhage in the short term (one to two days) and hydrocephalus in the long term (two to 30 days) to intervene early if needed.

Intracranial meningeal convexity chondroma is a rare benign lesion hypothesized to stem from remnant chondrocyte precursors of embryonic origin. This lesion often masquerades as meningioma given the similar dural-based attachment and pattern of calcification. We describe the case of a 26-year-old female with incidentally discovered convexity meningeal chondroma, originally presumed to be a meningioma. In this case, we share our diagnostic and operative intervention and outcome and discuss the unique pathologic findings in this lesion that differentiate it from similar appearing lesions. To the authors\' knowledge, there are fewer than 20 cases of convexity meningeal chondroma in the literature; thus, we also provide a brief review of the literature regarding this rare pathology.

Pleomorphic xanthoastrocytoma is a rare brain tumor of WHO grade II designation. This case report describes the author\'s experience with the discovery of the tumor, living with the tumor, and eventual treatment and aftermath of how it affected her life and her understanding of the medical system.

Stereotactic navigation and functional magnetic resonance imaging (fMRI) are increasingly used as important tools for intraoperative guidance and preoperative mapping for lesions in eloquent areas. We report a case in which a WHO grade II oligodendroglioma in Broca\'s area with functional activation was successfully resected with the support of blood-oxygen-level-dependent imaging (BOLD)-fMRI mapping in a patient who refused an awake craniotomy. This case highlights key principles of tumor surgery navigation. Specifically, it calls into question the utility of awake craniotomy in this modern era. Ultimately, fMRI is an important tool for tumor resections and can limit the need for more expensive or invasive measures.