Distribution of Natural Radioactivity from 40K\text{}^{40}K Radioelement in Volcanics of Sandıklı-Şuhut (Afyon) Area

Many radioactive elements have existed when the Earth had appeared and the long living of them are still present. One of the most important of these radioactive elements is $\text{}^{40}K$. It makes about 0.012% of total content of K, widely represented in many different rocks. In this study the distribution of the natural $\text{}^{40}K$ radioelement in the volcanics of the south part of Afyon was investigated. Gamma-ray spectrometer was used for in-situ measurements of this radioelement concentration. Studied area has covered approximately 1800 km². In-situ measurements were performed at 1390 different locations in this field. Data for each measurement was gathered during 3 min. The map of the ^{40}K element distribution in the studied area was produced. The high values of $\text{}^{40}K$, according to this map, were obtained in the areas of the alteration zones, between Sandıklı and Şuhut in the studied area

An Alternative Endoscopic Anterolateral Route to Meckel\u27s Cave: an Anatomic Feasibility Study Using a Sublabial Transmaxillary Approach

Objective: To describe an endoscopic anterolateral surgical route to the lateral portion of Meckel\u27s cave. Methods: A sublabial transmaxillary transpterygoid approach was performed in 6 cadaveric heads (12 sides). A craniectomy was drilled between the foramen rotundum (FR) and foramen ovale (FO) with defined borders. Extradural dissection was performed up to the V2–V3 junction of the trigeminal ganglion. The working space was analyzed using anatomic measurements. Results: The approach allowed for extradural dissection to the lateral aspect of Meckel\u27s cave and provided excellent exposure of V2, V3, and the V2–V3 junction at the gasserian ganglion. The mean distance between the FR and FO along the pterygoid process of the sphenoid bone was 21.3 ± 2.8 mm (range, 18–24.4 mm). The mean distance of V2 and V3 segments from their foramina to the gasserian ganglion junction was 12.0 ± 2.3 mm (range, 9.2–14.6 mm) and 15.2 ± 2.7 mm (range, 12.3–18.5 mm), respectively (6 sides). A potential working area (mean area, 89 mm2) is described. Its superior edge is from the FR to the V2–V3 junction at the gasserian ganglion, its inferior edge is from the FO to the V2–V3 junction at the gasserian ganglion, and its base is from the FO to the FR. The surgical anatomy of the infratemporal fossa, pterygopalatine fossa, and lateral Meckel\u27s cave is highlighted. Conclusions: An endoscopic anterolateral sublabial transmaxillary transpterygoid approach between the FR and FO avoids crossing critical neurovascular structures within the cavernous sinus and pterygopalatine fossa and can provide a safe surgical corridor for laterally based lesions in Meckel\u27s cave

Probe-based three-dimensional confocal laser endomicroscopy of brain tumors: technical note

Evgenii Belykh,1 Arpan A Patel,1 Eric J Miller,1 Baran Bozkurt,1 Kaan Yağmurlu,1 Eric C Woolf,2 Adrienne C Scheck,2 Jennifer M Eschbacher,3 Peter Nakaji,1 Mark C Preul1 1Department of Neurosurgery, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA; 2Neuro-Oncology Research, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA; 3Department of Neuropathology, Barrow Neurological Institute, St. Joseph’s Hospital and Medical Center, Phoenix, AZ, USA Background: Confocal laser endomicroscopy (CLE) is used during fluorescence-guided brain tumor surgery for intraoperative microscopy of tumor tissue with cellular resolution. CLE could augment and expedite intraoperative decision-making and potentially aid in diagnosis and removal of tumor tissue.Objective: To describe an extension of CLE imaging modality that produces Z-stack images and three-dimensional (3D) pseudocolored volumetric images.Materials and methods: Hand-held probe-based CLE was used to collect images from GL261-luc2 gliomas in C57BL/6 mice and from human brain tumor biopsies. The mice were injected with fluorescein sodium (FNa) before imaging. Patients received FNa intraoperatively, and biopsies were imaged immediately in the operating room. Some specimens were counterstained with acridine orange, acriflavine, or Hoechst and imaged on a benchtop confocal microscope. CLE images at various depths were acquired automatically, compiled, rendered into 3D volumes using Fiji software and reviewed by a neuropathologist and neurosurgeons.Results: CLE imaging, Z-stack acquisition, and 3D image rendering were performed using 19 mouse gliomas and 31 human tumors, including meningiomas, gliomas, and pituitary adenomas. Volumetric images and Z-stacks provided additional information about fluorescence signal distribution, cytoarchitecture, and the course of abnormal vasculature.Conclusion: 3D and Z-stack CLE imaging is a unique new option for live intraoperative endomicroscopy of brain tumors. The 3D images afford an increased spatial understanding of tumor cellular architecture and visualization of related structures compared with two-dimensional images. Future application of specific fluorescent probes could benefit from this rapid in vivo imaging technology for interrogation of brain tumor tissue. Keywords: 3D microscopy, confocal laser endomicroscopy, fluorescein sodium, fluorescence-guided brain tumor resection, glioma, brain tumor, volumetric imagin

Internal carotid artery injury in transsphenoidal surgery: Tenets for its avoidance and refit—a clinical study

One of the most serious/potentially fatal complications of transsphenoidal surgery (TSS) is internal carotid artery (ICA) injury. Of 6230 patients who underwent TSS, ICA injury occurred in 8 (0.12%). The etiology, possible treatment options, and avoidance of ICA injury were analyzed. ICA injury occurred at two different stages: (1) during the exposure of the sella floor and dural incision over the sella and cavernous sinus and (2) during the resection of the cavernous sinus extension of the tumor. The angiographic collateral blood supply was categorized as good, sufficient, and nonsufficient to help with the decision making for repairing the injury. ICA occlusion with a balloon was performed at the injury site in two cases, microcoils in two patients, microcoils plus a single barrel extra-intracranial high-flow bypass in one case, stent grafting in one case, and no intervention in two cases. The risk of ICA injury diminishes with better preoperative preparation, intraoperative navigation, and ultrasound dopplerography. Reconstructive surgery for closing the defect and restoring the blood flow to the artery should be assessed depending on the site of the injury and the anatomical features of the ICA. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Largest neurosurgical social media group and its impact on communication and research

BACKGROUND: The use of social media to communicate and disseminate knowledge has increased exponentially, especially in the field of neurosurgery. 'Neurosurgery cocktail' (NC) was developed by a group of young neurosurgeons as a means of sharing didactic materials and clinical experiences via social media. It connects 35.000 neurosurgeons worldwide on multiple platforms, primarily Facebook and Twitter. Given the rising utilization of social media in neurosurgery, the popularity of NC has also increased since its inception. In this study, the authors surveyed the social media analytics of NC for both Facebook and Twitter. Besides, we reviewed the literature on the use of social media in neurosurgery. METHODS: Facebook and Twitter metrics were extracted through each respective platform's analytics tools from December 2020 (earliest available date for data analysis) through January 2021. A literature search was conducted using PubMed (MEDLINE) and Scopus databases. RESULTS: On Facebook, as of January 2021, the group had a total of 25.590 members (87.6% male), most commonly (29%) between 35 and 44 years of age with over 100 countries were represented. As of January 2021, they had amassed 6457 followers on Twitter. During the last 28 d between December 2020 and January 2021, the account published 65 tweets that garnered a total of 196,900 impressions. Twelve articles were identified in our literature review on the use of social media within the neurosurgical community. CONCLUSIONS: NC is one of the most widely utilized neurosurgical social media resources available. Sharing knowledge has been broadened thanks to the recent social media evolution, and NC has become a leading player in disseminating neurosurgical knowledge