Alp Özgün Börcek

Arachnoid cysts are congenital, cerebrospinal fluid-filled sacs, predominantly asymptomatic and often detected incidentally. Spontaneous rupture of arachnoid cysts is an exceedingly rare complication, particularly in pediatric patients, and may present with acute neurological symptoms, including cranial nerve palsies. We report a 7-year-old male with a large, left middle fossa arachnoid cyst, initially asymptomatic and followed conservatively for five years. The patient developed resistant headache, vomiting, and right sixth cranial nerve palsy. Neuroimaging revealed spontaneous cyst rupture with resultant subdural hygroma and midline shift. The patient underwent successful endoscopic cyst fenestration with significant symptomatic improvement and complete resolution of cranial nerve palsy at six-month follow-up. A review of the literature identified fewer than ten pediatric cases of spontaneous arachnoid cyst rupture associated with cranial nerve deficits. Trauma is the most commonly reported precipitant; however, non-traumatic rupture mechanisms such as increased intracranial pressure have been postulated. Surgical intervention remains the mainstay treatment in symptomatic ruptures, typically yielding favorable outcomes. Spontaneous rupture of arachnoid cysts, although rare, should be considered in patients presenting with new neurological symptoms during follow-up. Early recognition and prompt surgical management are essential to prevent potentially severe complications. Close clinical surveillance is recommended even in asymptomatic cases to detect subtle clinical changes indicative of rupture.

This article presents a new benchmark MRI dataset called the Gazi Brains Dataset 2020, containing MRI images of 100 patients, and introduces initial experimental results performed on this dataset in comparison with available brain MRI datasets. Furthermore, the dataset is analyzed using eight different deep learning models for high-grade glioma tumor prediction, classification, and detection tasks. Additionally, this study demonstrates the results of an explainable Artificial Intelligence (XAI) approach applied to the trained models. To demonstrate the utility of the proposed dataset, different deep learning models were applied to the problem, and these models were tested on various data and models applied for various tasks such as region of interest extraction, whole tumor segmentation, prediction, detection, and classification with accuracy, precision, recall, and F1-score. The experimental results indicate that the dataset is highly effective for multiple purposes, and the models reached significant results with successful F1-scores ranging between 93.2% and 96.4%. ROI and whole tumor segmentations were successfully performed and compared with seven algorithms with accuracies of 87.61% and 97.18%. The Grad-CAM model also demonstrated satisfactory accuracy across the tests that were conducted. Moreover, this study explores the application of XAI to the trained models, providing interpretability and insights into the decision-making processes. The findings signify that this dataset holds significant potential for various future research directions, including age estimation, gender detection, causal inference with XAI, and disease-related survival analysis.

Purpose: In this article, we aimed to contribute to the literature by describing our approach to pediatric pineal and tectal masses treated with endoscopic interventions in our clinic. Materials and methods: We retrospectively reviewed the records of 26 patients with lesions in the pineal and tectal regions who underwent endoscopic procedures between 2012 and 2023 at Gazi University Department of Pediatric Neurosurgery. Demographic data, blood tumor markers (alpha fetoprotein-BETA AFP, alpha fetoprotein-β-hCG), pathological diagnoses, reasons for clinical presentation, presence of hydrocephalus and additional interventions were analyzed. Results: Of the 26 patients who underwent endoscopic procedure, 6 had lesions in the pineal region and 20 had lesions in the tectal region. The success rate for ETV was 75-80%. The success rate for ETV was 78.3% for patients with tumors in the pineal region and 84% for tectal tumors. Conclusion: Pineal or tectal region tumors are a rare group of tumors. In addition, these regions are among the most heterogeneous regions in the central nervous system in terms of tumor type and histology. Endoscopic intervention through a single burr hole using rigid endoscopy is a comfortable and safe minimally invasive method for both pathologic sampling and management of hydrocephalus in indicated cases in the same session.

Tumors of the pineal region (TPRs) are rare neoplasms that are surgically challenging to resect. Conventional treatment strategies are available, but gamma knife radiosurgery (GKRS) is an alternative approach. This study presents a single-center experience with GKRS performed for TPR with and without histopathological diagnoses. The cases of 25 patients with TPRs treated with GKRS were retrospectively analyzed. Thirteen of these 25 patients had histopathological confirmation, and 13 had elevated serum alpha-fetoprotein and beta-human chorionic gonadotropin levels. The 25 patients had a mean follow-up duration of 61 months. The total response rate to GKRS was 60%, and a 53.8% decrease in the alpha-fetoprotein and beta human chorionic gonadotropin levels was observed. The findings of this study indicate that GKRS is a safe procedure for TPRs, even in the event of insufficient histopathological findings. This treatment approach provides increased Karnofsky performance scores and an extended life expectancy.

Background/Aim: Pediatric neuroanesthesia is a special field that requires significant experience and infrastructure because of anatomical, neurological, and pharmacological differences in the pediatric patient population. Although technological improvements provide more effective and safer neuroanesthesiological management, the principles of neuroanesthesia, neurocognitive development, and the effects of anesthetic agents on central nervous system development are well-known. The majority of pediatric neuroanesthesia articles in the literature are reviews; however, retrospective/prospective case series and controlled research are limited. In this retrospective cohort study, we aimed to contribute to the existing literature by reviewing and analyzing our single-center 10-year experiences and results addressing pediatric neuroanesthesia management. Methods: After ethical committee approval, anesthetic and surgical reports from 1165 pediatric neurosurgical cases over ten years were collected. Demographic data, intra-operative vascular management, anesthesia techniques, airway management, patient positions, analgesia methods, and complications were evaluated in this retrospective cohort study. The available surgical intervention, patient positions, intra-operative neuromonitorization (IONM), and intra-operative magnetic resonance imaging (IOMR) records were also analyzed. Results: Six-hundred forty-six (55.4%) girls and 519 (44.5%) boys were included in the study. The median age was 60 (0–216) months. Cranial interventions were performed in 842 (72.3%) patients, and spinal interventions were performed in 323 (27.7%) patients. Patients’ American Society of Anesthesiologists (ASA) physical scales grouped as I, II, III, and IV were 718 (61.6%), 360 (30.9%), 82 (7%), and 5 (0.4%), respectively. Sevoflurane (40.3%), propofol (37.2%), and sodium thiopental (2.5%) were used for anesthetic induction. Neuromuscular block was performed with rocuronium (56.7%) and atracurium (14.4%). Neuromuscular blocking agents were not used in 337 patients (28.9%). A blood transfusion was required in 120 patients (10.3%), and 40% of these patients underwent surgery for craniosynostosis. Two-hundred twenty-two (19.1%) were monitored with IONM, and IOMR was carried out in 124 (10.6%) of the cases. The anesthesia-related complication rate was 5.15% (60 patients). Conclusion: Although pediatric neurosurgical interventions involve high risks, they are becoming increasingly common in our daily practice. Neuroanesthesiologists should know the procedures, techniques, and advances for safe and effective management of pediatric neurosurgical cases. We think that these data may be helpful as a guide for the anesthetic management of pediatric neurosurgical cases. '+st+' Rath GP, Dash HH. 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DOI: https://doi.org/10.1093/bja/88.1.12 Copyright (c) 2023 Gökçen Emmez, Gözde İnan, Hasan Kutluk Pampal, Volkan Şıvgın, Aslıhan Güleç Kılıç, Alp Özgün Börcek, Zerrin Özköse Şatırlar This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

OBJECTIVE: Cerebral cavernous malformation (CM) is an angiographically occult vascular pathology. Although microsurgery is the gold standard treatment to control the symptoms of CM, resection carries high risk in some situations, especially eloquent areas. The objective was to evaluate annual hemorrhage rates (AHRs) before and after stereotactic radiosurgery (SRS) treatment of cerebral CM in different locations. METHODS: A total of 195 patients (119 women and 76 men) with CM treated at the Gazi University Gamma Knife Center between April 2005 and June 2017 were analyzed. The mean ± SD follow-up period was 67.4 ± 31.1 months (range 12 days to 170 months). AHR before SRS, AHR after SRS, morbidity associated with radiation, seizure control rate after SRS, lesion volume, coexistence with developmental venous anomaly, and SRS treatment parameters were analyzed, with evaluation of radiological data and clinical charts performed retrospectively. The seizure control rate was assessed using the Engel outcome scale. RESULTS: The AHR before SRS was 15.3%. Application of SRS to these patients significantly reduced the AHR rates to 2.6% during the first 2 years after treatment and to 1.4% thereafter. Favorable seizure control (Engel class I and II) after radiosurgery was achieved in 23 patients (88.5%) with epilepsy. Radiation-related temporary complications occurred in 15.4% of patients, and permanent morbidity occurred in 4.6%. CONCLUSIONS: SRS is a safe and effective treatment modality for reducing the hemorrhage risk of CM. The authors suggest that SRS should be considered for the treatment of patients with CM, high surgical risks, and hemorrhage history, instead of a using a wait-and-see policy.

Sagittal imbalance is common in degenerative and congenital spinal diseases. Some studies have examined spinal deformities in the spina bifida. However, sagittal spinopelvic parameters in tethered cord syndrome (TCS) and split cord malformation (SCM) have been poorly evaluated in the literature. In this study, we investigated sagittal spinopelvic differences in TCS due to fatty filum terminale and SCM patients. A total of 78 patients with spina bifida occulta (30 SCM and 48 TCS due to fatty filum terminale) were included in the study. Radiological images of these patients were retrospectively evaluated. We evaluated the pelvic incidence, pelvic tilt, sacral slope, sagittal vertical axis (SVA), T1 pelvic angle, lumbar lordosis (LL), thoracic kyphosis, thoracolumbar alignment, and change in those parameters with age. Correlation coefficients between age and LL, T1 pelvic angle, and the SVA in patients with TCS due to fatty filum terminale were statistically significant. In addition, correlation coefficients between age and LL and the SVA in patients with SCM were statistically significant. Notably, LL was increased at a statistically significant level with age in patients with TCS and SCM. Improved knowledge of spinal balance parameters in patients with TCS and SCM may be helpful in understanding the clinical course of these pathologies, and provide information regarding the success of surgery at the follow-up period.

Aim: This study was performed to compare the effects of dexamethasone and melatonin against brain and spinal cord injury due to ionizing radiation models in rats. Methodology: Irradiated rats receive one LD50 dose (6,75 Gy) of whole-body ionizing radiation. A total of 48 male Wistar albino rats were randomized into four groups which have two different follow-up periods (24h and 72h): 1) Sham groups (S24 and S72), 2) Control groups which were irradiated (C24 and C72), 3) Dexamethasone administrated groups (0,25 mg/kg) after irradiation (D24 and D72), 4) Melatonin administrated groups (10 mg/kg) after irradiation (M24 and M 72). In addition, brain oedema, oxidative stress (evaluated by GSH and MDA assays), and histopathologic tissue damage scores were assessed. Results: Brain water contents were higher in control groups but were similar with dexamethasone and melatonin administrated groups compared to sham groups. In addition, oxidative stress was reduced with melatonin administration. Also, dexamethasone administration prevents an increase of brain MDA in both the follow-up period and decrease of spinal GSH level in 72h follow-up period. Conclusion: Histopathologic examination revealed that melatonin was as effective as dexamethasone to reduce neuronal tissue damage. Taking all these points into consideration suggests that melatonin can be related to protecting CNS injury induced by irradiation.