Comparison of the lateral supraorbital approach and endoscopic endonasal transclival approach to basilar apex aneurysms among other possible applications of the endoscopic endonasal technique to vascular neurosurgery: anatomic and clinical study.

Abstract Introduction. The expansion of the endoscopic endonasal approach in neurosurgery during the last three decades recently led the neurosurgical clinical interest to the investigation of further application of this technique, namely to neurovascular pathologies. Cadaver dissections studies have represented the milestone in the progressive application of this technique. Integrating anatomical studies with advanced visualization tools and quantification methods increases their impact toward clinical application. Material and methods. The main endoscopic endonasal approaches were performed and exposure of the vascular intracranial structures was analyzed: the anterior communicating artery complex was investigated through the transplanum transtuberculum approach; the transsphenoidal approach to the sellar area was performed for the exposure of the intracavernous internal carotid artery; the basilar artery was exposed by means of the endoscopic endonasal transclival approach, and the vertebral arteries through the extended endonasal approach to the craniovertebral junction. Possible clinical application of each approach was investigated during anatomical dissections upgraded with imaging and quantification methods. Results. The transtuberculum transplanum approach allows for the exposure and control of the anterior communicating artery complex; the relationship between the proximal anterior cerebral artery, gyrus rectus, and optic chiasm is the main determinant for the exposure and control of the vessel. Temporary occlusion of the internal carotid artery with a Fogarty balloon catheter through the endoscopic transsphenoidal route might be another maneuver that is useful for obtaining intraoperative control of the vessel. The endoscopic transclival approach may be considered a minimally invasive route to the basilar apex in the presence of specific anatomical and pathological features. Comparative analysis of the anatomical exposure of the vertebro-basilar junction as obtained through transcranial and endoscopic endonasal approaches may be helpful in unlocking this complex skull base area. Conclusions. The introduction of the endoscopic endonasal approaches for the treatment of cerebrovascular pathologies represents the most advanced and innovative step forward of the skull base endoscopic endonasal surgical technique. The present PhD research activity may add relevant anatomical and clinical information to the rather sparse literature directly focused on surgical indication of the endoscopic endonasal approaches to vascular neurosurgery

VITOM®-3D in lumbar disc herniation: Preliminary experience

Objectives: In neurosurgery, optimal illumination and surgeon view's magnification are essential to perform delicate and dangerous operations, such as aneurysms clipping and tumors removal. In this paper, the authors report their initial experience using a 3D-exoscope in spinal surgical procedures. Patients and methods: From January to July 2018 we performed 9 lumbar discectomies using a VITOM®-3D exoscope. We decided to examine these cases, with particular attention to the surgical timing and to the postoperative results in terms of pain control (VAS). Patient positioning, surgical instruments and approach technique were essentially the same used routinely in standard spinal disc herniation surgery.A "control" group composed of 9 cases was selected from patients who underwent a standard discectomy during the same period with the same neurosurgeons in order to obtain two homogeneous and comparable populations. Results: The length of operative time was measured and appeared to be longer in exoscope-assisted discectomies than in the traditional procedures (average 160 min vs 133 min); moreover the one-month postoperative VAS of the two groups were collected and compared but, after a statistical analysis, these differences resulted to be not statistically significant. No technical difficulties or surgical complications were noted. Conclusions: Despite the limited group of patients, the VITOM®-3D exoscope can be considered an interesting instrument in spinal procedures. It cannot permanently substitute the operating microscope but it shows interesting characteristics that make it a useful tool for surgeon's comfort and a versatile and relatively economic instrument in the neurosurgical armamentarium, as a part of a 3D working station composed by endoscope and exoscope. Keywords: Exoscope, Lumbar disc herniation, VITOM®-3D, Discectom

Verb generation for presurgical mapping: Gaining specificity

Verb generation is among the most frequently used tasks in presurgical mapping. Because this task involves many processes, the overall brain effects are not specific. While it is necessary to identify the whole network involving noun comprehension or semantic retrieval and lexical selection to produce the verb, isolation of those components is also crucial. Here, we present data from four patients undergoing presurgical brain mapping. The study implied a reanalysis of magnetoencephalography data with a recategorization of the used items. It aimed to extract the task component that relies on the inferior frontal gyrus (IFG). The task could be applied with higher specificity when targeting frontal areas. For that, we based item classification on the selection demands imposed by the noun. It is a robust finding that the IFG carries out this selection and that a quantitative index can be calculated for each noun, which depends on the selection effort (Proceedings of the National Academy of Sciences of the United States of America, 1997; 94(26):14792–14797, Proceedings of the National Academy of Sciences of the United States of America, 1998; 95(26):15855–15860). Data showed focality and specificity, with a correlation between this derived index and source activations in the inferior frontal gyrus for all patients. Strikingly, we detected when the right‐hemisphere homologue area was involved in the selection process in two patients showing reorganization or language right lateralization. The present data are a step towards a dissection of broad specific tasks frequently used in presurgical protocols

Molecular Mechanisms of HIF-1α Modulation Induced by Oxygen Tension and BMP2 in Glioblastoma Derived Cells

BACKGROUND: Glioblastoma multiforme (GBM) is one of most common and still poorly treated primary brain tumors. In search for new therapeutic approaches, Bone Morphogenetic Proteins (BMPs) induce astroglial commitment in GBM-derived cells in vitro. However, we recently suggested that hypoxia, which is characteristic of the brain niche where GBM reside, strongly counter-acts BMP effects. It seems apparent that a more complete understanding of the biology of GBM cells is needed, in particular considering the role played by hypoxia as a signaling pathways regulator. HIF-1alpha is controlled at the transcriptional and translational level by mTOR and, alike BMP, also mTOR pathway modulates glial differentiation in central nervous system (CNS) stem cells. METHODOLOGY/PRINCIPAL FINDINGS: Here, we investigate the role of mTOR signaling in the regulation of HIF-1alpha stability in primary GBM-derived cells maintained under hypoxia (2% oxygen). We found that GBM cells, when acutely exposed to high oxygen tension, undergo Akt/mTOR pathway activation and that BMP2 acts in an analogous way. Importantly, repression of Akt/mTOR signaling is maintained by HIF-1alpha through REDD1 upregulation. On the other hand, BMP2 counter-acts HIF-1alpha stability by modulating intracellular succinate and by controlling proline hydroxylase 2 (PHD2) protein through inhibition of FKBP38, a PHD2 protein regulator. CONCLUSIONS/SIGNIFICANCE: In this study we elucidate the molecular mechanisms by which two pro-differentiating stimuli, BMP2 and acute high oxygen exposure, control HIF-1alpha stability. We previously reported that both these stimuli, by inducing astroglial differentiation, affect GBM cells growth. We also found differences in high oxygen and BMP2 sensitivity between GBM cells and normal cells that should be further investigated to better define tumor cell biology

Comparison of the lateral supraorbital approach and endoscopic endonasal transclival approach to basilar apex aneurysms among other possible applications of the endoscopic endonasal technique to vascular neurosurgery: anatomic and clinical study.

Abstract Introduction. The expansion of the endoscopic endonasal approach in neurosurgery during the last three decades recently led the neurosurgical clinical interest to the investigation of further application of this technique, namely to neurovascular pathologies. Cadaver dissections studies have represented the milestone in the progressive application of this technique. Integrating anatomical studies with advanced visualization tools and quantification methods increases their impact toward clinical application. Material and methods. The main endoscopic endonasal approaches were performed and exposure of the vascular intracranial structures was analyzed: the anterior communicating artery complex was investigated through the transplanum transtuberculum approach; the transsphenoidal approach to the sellar area was performed for the exposure of the intracavernous internal carotid artery; the basilar artery was exposed by means of the endoscopic endonasal transclival approach, and the vertebral arteries through the extended endonasal approach to the craniovertebral junction. Possible clinical application of each approach was investigated during anatomical dissections upgraded with imaging and quantification methods. Results. The transtuberculum transplanum approach allows for the exposure and control of the anterior communicating artery complex; the relationship between the proximal anterior cerebral artery, gyrus rectus, and optic chiasm is the main determinant for the exposure and control of the vessel. Temporary occlusion of the internal carotid artery with a Fogarty balloon catheter through the endoscopic transsphenoidal route might be another maneuver that is useful for obtaining intraoperative control of the vessel. The endoscopic transclival approach may be considered a minimally invasive route to the basilar apex in the presence of specific anatomical and pathological features. Comparative analysis of the anatomical exposure of the vertebro-basilar junction as obtained through transcranial and endoscopic endonasal approaches may be helpful in unlocking this complex skull base area. Conclusions. The introduction of the endoscopic endonasal approaches for the treatment of cerebrovascular pathologies represents the most advanced and innovative step forward of the skull base endoscopic endonasal surgical technique. The present PhD research activity may add relevant anatomical and clinical information to the rather sparse literature directly focused on surgical indication of the endoscopic endonasal approaches to vascular neurosurgery

VITOM®-3D: preliminary experience with intradural extramedullary spinal tumors

Background: In the last decade, application of the high-definition exoscope to different neurosurgical procedures has been reported in the literature. We described the first experience with the VITOM®-3D (Video Telescope Operating Microscope, Karl Storz Endoscopy, Tuttlingen, Germany) for the surgical treatment of intradural extra-medullary tumors. Methods: Five neurosurgical procedures for the removal of intradural extra-medullary tumors were performed with the VITOM®-3D. Patients' population, feasibility of surgery under the exoscope visualization, VITOM®-3D's technical and optical characteristics, and surgical outcome were analyzed. Results: All surgeries were performed following the common steps of spinal neurosurgical intradural procedures. The exoscope offered excellent, magnified, and brilliantly illuminated high-definition images of the surgical field in all the described cases. All the reported surgical operations were successfully completed under exoscope magnification from both the technical as well as the clinical points of view. No complications potentially related to the use of the exoscope occurred. Working environment ergonomics and trainees learning experience were the most relevant benefits associated with the use of exoscope. Conclusions: VITOM®-3D may represent a valid visualization tool in spinal procedure for intradural extra-medullary tumors. Our preliminary experience can be useful in better define the role of VITOM®-3D in neurosurgery

Vitom 3D: preliminary experience with intradural extramedullary spinal tumors

In the last decade, application of the high-definition exoscope to different neurosurgical procedures has been reported in the literature. We describe the first experience with the VITOM\uae-3D for the surgical treatment of intradural extra-medullary tumors