The Study Of Poppen Approach Operation In Microscopic Anatomy

Objective Surgical treatment is tends of pineal region tumors at present. Poppen approach to the pineal region is highly recommended because of proximity of tumor and spacious vision and so on. The cistem, vein and artery in pineal region have complex anatomy structure and importment function, the injury of deep venous system in brain can cause serious result. There is little research in microscopic anatomy of Poppen approach and the quantitative research in main artery and vein is less. Our experiment provides anatomical guidance for the use of Poppen approach resction of various tumors in pineal region by the reseach of its microscopic anatomy.Methods 15 adult cadaveric head specimens were perfusion which provided by depertment of anatomy, Anhui Medical University. The perfusioned specimens were dissected under microscope, analog parietooccipital suboccipital supratentotial craniotomy approach (Poppen approach). The importment anatomical structures realated to this approach were observed, photoed and measured.Results The relevant improtment structures incluinding quadrigeminal pool, straight sinus, basal vein (BV), Galen's vein (GV), interal cerebral vein (ICV) and posterior cerebral artery (PCA) can be seen in Poppen approach. Quandrigeminal pool is constituted by the double arachnoid form the corpus callosum and surrounding the large brain vein, it is the continuation of the choroid tissue around the interpositum. The trochlear nerve (TN) comes into the quandrigeminal from the cerebellar tentorium, which side of midbrain surface into the ambient cistern. BV is conclude by cerebral infanteriores vein (CIV) and cerebral media profounda vein (CMPV) which converge at anterior perforated substania, bypass the cerebral penduncle and into the quadrigeminal pool. According to the site drainage and the order, BV can be divided into three sections: section of striatum, cerebral peduncle section and midbrain section. The midbrain section closed to ipsilateral geniculate body's surface at its start, this section of BV is closely related with the operation of the pineal region. The strating postion of interal cerebral vein (ICV) is in the back of intertricular foreman, the two parallel veins'interval is 1~2mm, underwent along the top of the third ventricle. The ICVs separated from each other at plane of the corpus pineale, turn back and upon at the corpus callosum. The ICVs merged into the GV in the midline. The main branches of the ICV conclude thalamostriata vein, septum pellucidum vein and choridea vein. With these branches varying degrees cut off or ligation, different degrees of impact will produce because of ICV venous circulation is poor. The main stem of GV is below or back of the corpus callosum, posterior of the cerebellar tentorium, starting mainly in the pineal gland's back or upper back. Most of the GV is alone into the confluence of sinuses and a few is double. The angle between the GV and the confluence of sinuses is acute or close to right angle. Both the PCA and the superior cerebellar artery's (SCA) stem and branches are made from the front into the pineal region. The PCA start from basical artery (BA) and communicate with posterior communicating artery. The main beanches of PCA concludes long spiral artery (LSA), short spiral artery (SSA), thalamic geniculate artery (TGA), posterior medial choroidal artery (PMCA) and posterior lateral choroidal artery (PLCA). By measuring, we found that: the length of ICV is (34.26±5.43) mm, diameter is (1.56±0.37) mm; the length of BV is (35.41±6.62) mm, diameter is (1.42±0.38) mm; the length of GV is (9.64±4.11) mm, diameter is (3.78±1.62) mm. The distance between ICV and pineal gland is (3.21±1.15) mm; the distance between BV and pineal gland is (4.41±1.36) mm; the distance between GV and pineal gland is (6.54±3.14) mm. the bilateral ICVs'distance is as the first gap, the ipsilateral ICV and BV's distance is as the second gap. The narrowest is (1.22±0.54) mm in the first gap and the maximum width is (6.26±2.14) mm; the narrowest is (1.25±0.36) mm in the second gap and the maximum width is (10.22±0.76) mm.Conclusion Poppen approach is a safe and effective method for removal of pineal region tumors. These approaches near the tumor, vision spacious, without ventricle, pure outside of brain operation, dose no damage of brain tissue, surgical response to light. The deep important veins are under dirct vision, the protection is easy. Weather the tumor is located deep wein above or below, this approach can be adopted. The importment blood vessels and nerves in pineal region can be fully exposed by this approach. The operation is ouside the brain parenchyma to aovid severe postoperative reaction. The measurement of the distance between the relevant structures provided important value for the predictablility of treatment and identifies the value of other structures, this experiment supply the anatomical basis of clinical surgery.