Endoscopic Endonasal Approach Limitations and Evolutions for Tuberculum Sellae Meningiomas: Data from Single-Center Experience of Sixty Patients.

AIM: To determine the limits, to show the effect of tumor consistency on resection rates and to present the sinonasal morbidity rate in patients with tuberculum sellae meningiomas who underwent endoscopic endonasal approach. MATERIAL AND METHODS: We reviewed the medical data, radiological images, and surgical videos of the patients with pathologically confirmed meningiomas originating from the tuberculum sellae and they were operated via endoscopic endonasal approach between August 1997 and December 2020. We used our endoscopic classification based on infrachiasmatic corridor. In this classification, tumors were divided into those within the infrachiasmatic corridor and proximity of the optic nerve, internal carotid artery, and anterior artery complex and those outside the infrachiasmatic corridor. RESULTS: Gross total resection was achieved in 45/60 (75%) patients. We found that tumor consistency was statistically significant on resection rates. Simultaneously, tumor median diameters on the anteroposterior (≤21.15 mm), transverse (≤19.75 mm), and superoinferior (≤15 mm) axes were statistically significant on resection rates. CONCLUSION: In summary, the most important factor in selecting the surgical technique is the tumor size. Infrachiasmatic corridor boundaries are the limitations of endoscopic approach. These limitations can change based on surgeon's experience. Also, tumor consistency is a factor that affecting degree of tumor resection rates.

Repeat endoscopic third ventriculostomy success rate according to ventriculostoma closure patterns in children.

PURPOSE: This study aimed to examine the success rate of repeat endoscopic third ventriculostomy (redo-ETV) according to pattern of ventriculostoma closure based on observations in 97 paediatric redo-ETV patients. METHODS: Clinical data and intraoperative video recordings of 97 paediatric hydrocephalus patients who underwent redo-ETV due to ventriculostoma closure at two institutions were retrospectively analysed. We excluded patients with a history of intraventricular haemorrhage, cerebrospinal fluid (CSF) infection or CSF shunt surgery and those with incompletely penetrated membranes during the initial ETV. RESULTS: Verification of ventriculostoma closure was confirmed with cine phase-contrast magnetic resonance imaging and classified into 3 types: type 1, total closure of the ventriculostoma by gliosis or scar tissue that results in a non-translucent/opaque third ventricle floor; type 2, narrowing/closure of the ventriculostoma by newly formed translucent/semi-transparent membranes; and type 3, presence of a patent ventriculostoma orifice with CSF flow blockage by newly formed reactive membranes or arachnoidal webs in the basal cisterns. The overall success rate of redo-ETV was 37.1%. The success rates of redo-ETV according to closure type were 25% for type 1, 43.6% for type 2 and 38.2% for type 3. The frequency of type 1 ventriculostoma closure was significantly higher in patients with myelomeningocele-related hydrocephalus. CONCLUSION: For patients with ventriculostoma closure after ETV, reopening of the stoma can be performed. Our findings regarding the frequencies of ventriculostoma closure types and the success rate of redo-ETV in paediatric patients according to ventriculostoma closure type are preliminary and should be verified by future studies.

Immunohistochemical analysis of TIMP-2 and collagen types I and IV in experimental spinal cord ischemia-reperfusion injury in rats.

BACKGROUND: Thoracic and thoracoabdominal aortic intervention carries a significant risk of spinal cord ischemia. The pathophysiologic mechanisms that cause hypoxic/ischemic injury to the spinal cord have not been totally explained. In normal spinal cord, neurons and glial cells do not express type IV collagen. Type IV collagen produced by reactive astrocytes is reported to participate in glial scar formation. Tissue inhibitors of metalloproteinases (TIMPs) are endogenous inhibitors that regulate the activity of the matrix metalloproteinases (MMPs). TIMP-2 binds strongly with MMP-2, facilitating activation by membrane-type MMP. Imbalance between TIMPs and MMPs can lead to excessive degradation of matrix components. Type IV collagen involved in the blood-brain barrier disruption and glial scar formation, TIMP-2 influences MMP-2 that controls degradation of collagen I and IV. OBJECTIVE: To examine the immunohistochemical analysis of TIMP-2 and collagen types I-IV in experimental spinal cord ischemia-reperfusion in rats. METHODS: Thirty-two male Wistar rats weighing 250-300 g were divided into four groups: group S: sham group (n = 8); group 0P: 30-minute occlusion without perfusion (n = 8); group 3P: 30-minute occlusion and 3-hour perfusion (n = 8); and group 24P: 30-minute occlusion and 24-hour perfusion (n = 8). Infrarenal aorta was cross-clamped at two sites by using two aneurysm clips for 30 minutes. Reperfusion was provided after removal of the clips. Lumbar spinal cord segments were removed for immunohistochemical analysis. RESULTS: TIMP-2 and collagen staining in 3-hour perfused (3P) group were nearly the same with sham group (S). TIMP-2 and collagen staining increased in the 24-hour perfused group. CONCLUSION: Alterations in collagen levels may relate to the biphasic breakdown of the blood-brain barrier and collagen staining in new cell types with relation to glial scar formation. Our results demonstrate that 3-hour perfusion after occlusion in hypoxic/ischemic spinal cord injury seems to be the critical reversible period.

Evaluation of early visual recovery in pituitary macroadenomas after endoscopic endonasal transphenoidal surgery: Quantitative assessment with diffusion tensor imaging (DTI).

BACKGROUND: Visual field analyses reflect the degree of the compression to the optic nerve that results the structural damage of the nerve. These structural damages can be evaluated by diffusion tensor imaging (DTI), which assesses the structural integrity of white matter tracts. Thus, we evaluated the quantitative assessment of early visual recovery in patients with pituitary macroadenomas, corresponding DTI with visual field analyses. METHODS: Seventy-two patients who had pituitary macroadenomas with visual field defects were included in the study retrospectively. All patients were operated on by pure endoscopic transphenoidal approach. Visual field assessment using Humphrey field analyzer and DTI with 3T magnet were performed in the preoperative and postoperative second day and sixth month. FINDINGS: Mean symptom duration was 14.7 ± 10.5 weeks in the full recovery group patients, 50.1 ± 29.1 weeks in partial recovery patients, and 92.4 ± 15.4 weeks in the ones with no recovery. There was a significant difference at p < 0.001 among the groups. On visual field analysis, the visual lost was mostly recognized at upper temporal levels preoperatively. Visual field findings of both eyes were improved in 80% of the patients. Among these, 25% revealed full recovery, 55.6% partial recovery, and 19.4% did not demonstrate significant changes. DTI assessments of affected sides revealed preoperative fractional anisotropy (FA) values below 0.400 and mean diffusivity (MD) values over 1,400 × 10(-6) mm(2) s(-1) were related with no visual improvement in the postoperative 6 months period. The percentage increase of mean FA values of the affected areas postoperatively were found to be 21.9% in totally responded patients, 20.6% in partial responded patients, and 9.8% in patients that did not respond. CONCLUSIONS: There is a correlation between DTI-derived FA values of the optic nerves and visual parameters. DTI assessments of the affected sides with FA and MD values may help to estimate the response of visual improvement to the surgical therapy in the early postoperative period.