Ендоваскулярна нейрорентгенохірургія (Mar 2017)
Individualization of the microsurgical stage of the operation in cases of the distal segment anterior cerebral artery aneurysms
Abstract
The objective – to improve results of the transcranial treatment of patients with the distal segment (DS) anterior cerebral artery (ACA) aneurysm by the usage of the individualized approach to the microsurgical stage of the operative intervention. Materials and methods. Retrospective analysis of 72 (100 %) microsurgical treatment cases of patients with 79 DS ACA AA that were performed in the SO «Institute of Neurosurgery named after acad. A.P. Romodanov of NAMS of Ukraine» during the period since 1998 until 2015 was carried out. Methods of the research included clinical, laboratory, instrumental and statistic. More than the half (55 %) of patients, by the admission to the hospital, had II—III stage of the severity by the modified Hunt-Hess scale. Among of them 83 % patients were operated in the acute period of the hemorrhage. Intracranial hemorrhage was in 90 % patients in this group, in 67 % patients were complicated forms of hemorrhage. Intracerebral hematoms were detected in 57 % patients. In 68 % cases lateral, axial or lateral and axial dislocations of the brain structures were detected. In 30% patients haemorrhages with the ventricular component were diagnosed. Results. By the form of the DS ACA AA among 79 (100 %) 77 (97.5 %) were saccular and 2 (2.5 %) fusiform. By the sizes AA in 91 % cases were small and medium. The AA dome was mainly directed to the anterior or superior direction 34 % with the location on the medial line in 86 %. The most often place of the DS ACA AA location was A3 segment (78 %). It was detected that the neck coefficient (2.6 ± 1.4) and artery coefficient (3.8 ± 2.4) were higher in AA that ruptured in comparison with the analogical coefficients (2.43 ± 1.21 and 3.3 ± 2.0) of aneurysms which didn't rupture. Aneurysms of the A2 segment – 14 (17.7 %) were operated in 12 patients by the different craniotomy accesses: pterional – 6, orbitozygomatic – 2, frontal interhemispheric – 4. Devascularization of AA A2 segment (14): simple clipping – 8, multiple clipping (clip reconstruction) – 4; fusiform AA were excluded by the wrapping and external remodelling of A2 segment by the fenestration tubes in 2 cases. All aneurysms of the A3 segment had saccular form – 78.5 % (62/79), in most cases 51.6 % (32/62) were small size with dome directed to the anterior and superior direction. By the clipping of DS ACA AA 62 (100 %) were used: simple clipping – 48 (77.4 %), multiple clipping with the clip reconstruction – 14 (22.6 %). Aneurysm of the A3-A5 segments was detected in one patient with 2 AA, of callosomarginal artery, of small and medium sizes with the dome directed to superior direction, that were devascularized by the simple clipping method. In all cases A3-A5 segment ACA AA parasagittal interhemispheric access was used. Conclusions. Individualization of the microsurgical stage of the operation is based on the taking into account: patient's condition, clinical disease, AA location on the DS ACA; comparison of the anatomic characteristics (length, width, neck width, dome direction with the diameter of artery that aneurysm located on) with form, volume and density of ICH, anatomic features of arterial bed and venous branch constitution and consist of: in the choice of optimal craniotomy; differentiated order concerning ICH exclusion, exclusion of the appropriate segments and AA; usage of different methods of AA clipping; providing intraoperational bloodstream monitoring in the damaged arterial segment and control of the AA devascularisation radicalism.
