Anatomical types of posterior part of the circle of Willis

Objective. To study the individual variability of posterior part of the circle of Willis and posterior cerebral arteries. Material and methods. We examined 50 basilar arteries, 100 posterior communicating arteries and 100 posterior cerebral arteries on 50 anatomical specimens of human brain. We conducted the morphometric examination of the types of posterior part of the circle of Willis, basilar artery (BA), posterior cerebral artery (PCA), posterior communicating arteries (PCoA) and perforating arteries. This anatomical study was conducted using the method of step-by-step microsurgical dissection with microphotography as well as modeling of surgical approaches and morphometry. Results. We revealed three types of posterior part of the circle of Willis: normal type was seen at 48% of cases while abnormal type (hypoplastic and fetal) - at 52% of cases. We stated the dependence between the diameter of Р1-segment of PCA and type of posterior part of the circle of Willis. The forming principle of straight perforating and circumferential arteries arising from the main segments of PCA, PCoA and BA as well as principles of posterior choroid arteries forming was described. The 4 models of vascular architectonics of PCA cortical branching were revealed and described. The 3 types of proximal bi(tri)furcation of Р2Р-segment of PCA and features of its localization in retrouncal area are described. Conclusions. The knowing of anatomical types of posterior part of the circle of Willis, basilar apex, PCA and topography of perforating arteries is necessary for choice of optimal approach to posterior part of the Willis circle whole clipping the vertebrobasilar aneurysms. The topography of proximal bi(tri)furcation of Р2Р-segment of PCA must be taking into account during subtenporal approaches for prevention the traction damage of brain.

фетальный и гипоплазированный типы строения задних отделов АКБМ, задняя мозговая артерия, задняя соединительная артерия, верхушка базилярной артерии, проксимальная бифуркация ЗМА, fetal and hypoplastic types of posterior part of the circle of Willis, posterior cerebral artery (PCA), posterior communicating artery, basilar apex, proximal bifurcation of PCA

1. Добровольский Г.Ф. Методологические основы топографической нейропато-морфологии мозга, основания черепа, шейного отдела позвоночника и структурных элементов системы ликворообращения. // М.: Компания Спутник, 2003.-49 с.

2. Завалишин Е.Е. и др. Топографо-анатомическое обоснование трансорального доступа к аневризмам вертебро-базилярного бассейна // VII Всероссийская научнопрактическая конференция «Поленовские чтения». - Материалы конференции. - СПб, 2007.

3. Люнькова Р.Н. и др. Индивидуальная изменчивость дистальной трети базилярной артерии. // XII Всероссийская научно-практическая конференция «Поленовские чтения». - Материалы конференции. - СПб, 2013.

4. Люнькова Р.Н. Хирургическая анатомия задней мозговой артерии // Вопросы прикладной анатомии и хирургии. Материалы IX региональной конференции СНО и молодых ученых медицинских ВУЗов и лабораторий НИИ. - СПб, 2003, стр. 70-81.

5. Микрохирургия аневризм виллизиева многоугольника // под ред. члена-корр. РАМН проф. В.В. Крылова. - М., 2004.

6. Микрохирургия аневризм головного мозга // под ред. проф. В.В. Крылова. - М., 2011, стр. 308-312.

7. Хирургия аневризм головного мозга // под ред. акад. РАМН проф. В.В. Крылова. В 3-х томах. М., 2011.Том II, стр. 339-380.

8. de Oliveira E., Tedeschi H., Siqueira M.G., Ono M., Rhoton A.L. Jr., Peace D. Anatomic principles of cerebrovascular surgery for arteriovenous malformations. Clin Neurosurg. 1994; 41: 364-380.

9. Campero A., Trocoli G., Fernandez-Miranda J.C., Rhoton A.L. Jr. Microsurgical approaches to the medial temporal region: an anatomical study. Neurosurgery. 2006; 59(4 Suppl 2). - Р 279 -307.

10. Fernandez-Miranda J.C., de Oliveira E., Rhoton A.L. Jr. Microvascular anatomy of the medial temporal region: Part I: Its Application to Arteriovenous malformation surgery. Neurosurgery. 2010; 67 Operative Neurosurgery 1 pp 237-276.

11. Erdem A., Yasargil G., Roth P. Microsurgical anatomy of the hippocampal arteries. J Neurosurg. 1993; 79(2): 256-265.

12. Huther G., Dorfl J., Van der Loos H., Jeanmonod D. Microanatomic and vascular aspects of the temporomesial region. Neurosurgery. 1998; 43(5): 1118-1136.

13. Margolis M.T., Newton T.H., Hoyt W.F. The posterior cerebral artery: gross and roentgenographic anatomy. In: Newton T.H., Potts D.G., eds. Radiology of the Skull and Brain. Vol. 2. St Louis, MO: CV Mosby; 1974: 1551-1578.

14. Marinkovic S.V., Milisavljevic M.M., Vuckovic V.D. Microvascular anatomy of the uncus and the parahippocampal gyrus. Neurosurgery. 1991; 29(6): 805-8l4.

15. Marinkovic S., Gibo H. Microanatomy of the intrachoroidal vasculature of the lateral ventricle. Neurosurgery. 2005; 57 (1 SuppI): 22-36.

16. Rhoton A.L. Jr: Cranial Anatomy and surgical approaches, Neurosergery. Lippincott Williams & Wilkins, 2006, 746 pp.

17. Seoane E.R., Tedeschi H., de Oliveira E., Rhoton A.L. Jr. Management strategies for posterior cerebral artery aneurysms: a proposed new surgical classification. Acta Neurochir (Wien). 1997; 139(4): 325-331.

18. Saeki N., Rhoton A.L. Jr: Microsurgical anatomy of the upper basilar artery and the posterior circle of Willis. J Neurosurg, - 1977, (46): 563-578.

19. Yasargil M. Microneurosurgery. Vol. I. Stuttgart, Germany: Georg Thieme Verlag; 1984.

20. Zeal A.A., Rhoton A.L. Jr. Microsurgical anatomy of the posterior cerebral artery. J Neurosurg. 1978; 48 (4): 534-559.