[An anatomical study on the applicability of direct endoscopic exclusion of the ethmoid arteries for devascularization of the anterior skull base structures]. / Anatomicheskoe issledovanie vozmozhnosti priamogo éndoskopicheskogo vykliucheniia reshetchatykh arterii dlia devaskuliarizatsii struktur perednikh otdelov osnovaniia cherepa.

The anterior skull base structures are the site of initial growth of histologically different tumors. The difficulties in their removal are often associated with significant vascularization, which may limit the amount of resection due to abundant intraoperative blood loss. Midline tumors are primarily fed by the ethmoid arteries that are not accessible to embolization. The aim of this work was a comparative experimental study of various direct approaches to the ethmoid arteries. MATERIAL AND METHODS: The study was conducted on anatomical specimens of 12 cadaveric heads of deceased people without pathology of the anterior skull base structures, orbits, nasal cavity, and paranasal sinuses (24 sides). In all specimens, the internal and external carotid arteries were stained with silicone. During anatomical dissection, four surgical approaches for exclusion of the ethmoid arteries were studied: 1) transorbital approach to the arteries using a bicoronal incision; 2) endoscopic retro-caruncular approach; 3) endoscopic endonasal transethmoidal approach to the ethmoid artery canals; 4) endoscopic endonasal transethmoidal transorbital approach to the ethmoid arteries in the orbit. RESULTS: We described a surgical technique for exclusion of the ethmoid arteries using the approaches and analyzed their advantages and disadvantages. We formulated an algorithm for choosing the method for direct endoscopic exclusion of the ethmoid arteries, depending on the surgical approach chosen for removal of the tumor and features of the tumor extracranial spread. CONCLUSION: The decision on tumor devascularization is based on assessment of tumor blood supply (CT angiography or MR angiography data). Our study demonstrated the advantages and disadvantages of various approaches to the ethmoid arteries for their exclusion in order to early devascularize anterior skull base tumors. All these approaches are less traumatic and characterized by a good cosmetic and functional outcome.

[A technique of manufacturing anatomical preparations of the human brain based on injecting vessels with colored silicone (a technical note)]. / Sposob izgotovleniia anatomicheskikh preparatov golovnogo mozga cheloveka s in''ektsiei sosudov tsvetnym silikonom (tekhnicheskoe opisanie).

OBJECTIVE: The objective was to produce anatomical preparations by injecting vessels with colored silicone to study the brain and skull base anatomy. MATERIAL AND METHODS: Fresh, undissected, and unfixed cadavers were used. The internal carotid arteries and internal jugular veins were identified on both sides of the neck. The vessels were washed with running water. Then, a complex solution consisting of white silicone rubber, silicone oil (solvent), and a coloring pigment (red and blue pigments) at a ratio of 1:(0.9-1.1):(0.04-0.06), respectively, was prepared. About 30-60 s before injecting the complex solution into the vessels, a catalyst-hardener was added to the solution at a ratio of 1:(0.05-0.07). The complex solution was first introduced into the internal carotid artery until the solution came out from the contralateral internal carotid artery; then, the solution was injected into the internal jugular vein until the solution emerged from the contralateral internal jugular vein. RESULTS: The technique enables quick and high-quality visualization of both large and very small vessels of the brain and skull base. CONCLUSION: The proposed simple and inexpensive technique of manufacturing anatomical preparations improves the quality of training and mastering of microsurgical skills in residents and practicing neurosurgeons.