Arteriovenous Fistulas: The Pathological Bridge

An intracranial dural arteriovenous fistula (DAVF) is a type of intracranial vascular malformation in which there is a connection between an intracranial artery and a dural venous sinus. It accounts for 10–15% of all intracranial arteriovenous malformations. This malformation derives its arterial supply primarily from meningeal vessels, and the venous drainage is either via dural venous sinuses or through the cortical veins. DAVFs have a reported association with dural sinus thrombosis, venous hypertension, previous craniotomy, and trauma, though many lesions are idiopathic. Digital subtraction angiography remains the gold standard for diagnosing these fistulas. Endovascular treatment is one of the first line options available for their management. In this chapter, we will discuss and review the etiopathogenesis, natural history, common classification systems, and various available diagnostic options

Effect of Depth of Total Intravenous General Anesthesia on Intraoperative Electrically Evoked Compound Action Potentials in Cochlear Implantation Surgery.

PURPOSE: This study aims to compare the effect of the depth of total intravenous anesthesia (TIVA) on intraoperative electrically evoked compound action potential (e-ECAP) thresholds in cochlear implant operations. METHODS: Prospectively, a total of 39 patients aged between 1 and 48 years who were scheduled to undergo cochlear implantation surgeries were enrolled in this study. Every patient received both light and deep TIVA during the cochlear implant surgery. The e-ECAP thresholds were obtained during the light and deep TIVA. RESULTS: After comparing the e-ECAP means for each electrode (lead) between the light and deep anesthesia, no significant differences were detected between the light and deep anesthesia. CONCLUSION: The depth of TIVA may have no significant influence on the e-ECAP thresholds as there was no statistical difference between the light and deep anesthesia

Silicone Oil Utilized in Pars Plana Vitrectomy for Patients with Advanced Proliferative Diabetic Retinopathy: Physico-Chemical and Optical Properties

Rami Al-Dwairi,1 Ahmad A Ahmad,2 Abdelwahab Aleshawi,1 Areen A Bani-Salameh,2 Ihsan A Aljarrah,2 Qais M Al-Bataineh,2,3 Seren Al Beiruti,1 Ali Omar Alshami,1 Edina Rusen,4 Gabriela Toader5 1Department of Special Surgery, Division of Ophthalmology, Faculty of Medicine, Jordan University of Science & Technology, Irbid, 22110, Jordan; 2Department of Physics, Thin Films and Nanotechnology Laboratory, Faculty of Science and Art, Jordan University of Science & Technology, Irbid, 22110, Jordan; 3Leibniz Institut für Analytische Wissenschaften‐ISAS‐e.V., Dortmund, 44139, Germany; 4Faculty of Chemical Engineering and Biotechnologies, University POLITEHNICA of Bucharest, Bucharest, 011061, Romania; 5Military Technical Academy “Ferdinand I”, Bucharest, 050141, RomaniaCorrespondence: Rami Al-Dwairi, Department of Special Surgery, Division of Ophthalmology, Faculty of Medicine, Jordan University of Science & Technology, P. O. Box: 3030, Irbid, 22110, Jordan, Tel +962799273019, Fax +962 2 7201064, Email [email protected]: Silicone oils have the role in maintaining the attachment of the retina in conditions where the risk of retinal re-detachment is high. However, silicone oils have the tendency to emulsify with subsequent complications. In this work, analyses have been performed to understand changes that occurred to the optical, and physical characteristics of the oil after removal from the vitreous cavity of patients underwent pars plana vitrectomy (PPV) for fibrovascular membranes/tractional retinal detachment (FVM/TRD).Methods: Four samples of silicone oil were allocated from patients who underwent PPV for FVM/TRD. The Fourier-transform infrared (FTIR) spectroscopy, micro-viscometry, and ultraviolet-visible spectrometer analyses were utilized to determine the changes in its chemical bondings, viscosity, absorbance, transmittance, buoyance, and specific gravity.Results: The mean age of the patients was 49.0 years. The mean duration of silicone oil implantation was 18.9 months. FTIR analysis showed significant breaking in the chemical bonding that was related to the lens status during the primary PPV, the presence of significant retinal hemorrhages, the duration of silicone oil implantation, and the degree of silicone oil filling. Similarly, viscosity and contact angle analyses revealed a reduction in the viscosity with similar factors to the FTIR analysis. Moreover, absorbance and transmittance were largely affected by the aggressiveness of FVM/TRD.Conclusion: This study revealed that certain factors such as the age of the patient, duration of silicone oil implantation, lens status, and the presence of retinal hemorrhages, the degree of silicone oil filling and aggressiveness of FVM/TRD may contribute to the emulsification process.Keywords: silicone oil, tractional retinal detachment, emulsification, viscosit