Microsurgical anatomic study of subtemporal approach using a minimal access / 中华显微外科杂志

Objective To investigate the surgical exposure of the subtemporal approach and explore clinical indications using a minimal-access.Methods Ten adult cadaveric heads fixed with formalin were used in this study.The holes with 3.0 cm × 2.5 cm of zygomatic arch vertically were operated on each head with subtemporal approach.During the anatomical procedures,measured the maximal exposure lengths of tentorial margin,posterior cerebral artery,and anterior border of brain stem,vertical distances between highest structure in the field of view and posterior clinoid process,the shortest distances form the zygomatic arch 1/3 to tentorial edge,sulcus lateralis mesencephali and anterior clinoid process; After tentorium of cerebellum was cut,measured the straight distance form the internal carotid artery to the optic nerve and form the posterior communicating artery to the tentorial edge.Results Oculomotor,trochlear nerve,tentorial edge,superior cerebllar artery.,P1-P2 segment of posterior cerebral artery,ventrolateral surface of mesencephalon and pon higher than root of trigeminal nerve,anterior and posterior clinoid process,posterior communicating artery and anterior choroidal artery,and superior portion of pituitary stalk could be observed via subtemporal approach using a minimal-access.Conclusion 1.The subtemporal approach using a minimal-access can protect the superficial temporal artery and the facial nerve branches especially in the process of the flap formation.It does little damage to the temporallis,reduces the invalid exposure of brain tissue,farthest lowers the damage to the scalp,skull and adjacent tissue ; 2.The subtemporal approach using a minimal-access can obtain the exposure rang.It can see the upper pons,petroclival region,tentorial notch area,ventrolateral brain stem.

Facial Nerve Schwannoma Located in Middle Cranial Fossa

Facial nerve schwannomas are uncommon tumors. A 40-year-old female presented with left-side facial weakness. Computed tomography(CT) imaging showed a 3 x 2cm lesion on the posterior portion of the left middle cranial fossa. The mass abutted the anterior aspect of the left petrous bone with a wide erosive change involving the area of the left facial nerve ganglion (geniculate ganglion). A well-circumscribed extra-axial mass was seen on magnetic resonance imaging(MRI). The tumor was completely removed through subtemporal approach and the patient was discharged without additional neurological deficit. This rare case is discussed and a review of the relevant literature is presented.

Subtemporal Approach for Cerebral Aneurysm / 대한뇌혈관학회지

Only about 15% of intracranial aneurysms involve the posterior circulation and about 80% of distal basilar aneurysms have their origin at the level of or above the posterior clinoid process. Therefore, they are potentially approachable via the pterional or trans-sylvian route. This imply that most neurosurgeons will relatively rarely be required to perform this procedure. Especially basilar bifurcation aneurysms arising substantially below the level of the posterior clinoid process or projecting posteriorly could be successfully repaired via subtemporal approach. There are number of unique surgical problems that can be best attacked through a subtemporal approach, and for this reason it is important to have facility with its performance and a detailed understanding of its advantages and limitations. Surgical tactics and pitfalls of subtemporal approach will be described with a basis of experiences in Yonsei University and review of literatures.

Distal Posterior Cerebral Artery Aneurysms: Report of 2 Cases

Two cases of aneurysms in the P3 segment of the posterior cerebral artery are described. These were managed by the subtemporal approach. One giant aneurysm in a 47-year-old male was treated by clipping the afferent artery, and the other small saccular aneurysm in a 41-year-old female was treated by clipping the aneurysmal neck. There were no complications after surgery, and the patients were discharged without neurological deficit. The operative approaches and procedures are also discussed in relation to the anatomy of posterior cerebral artery aneurysms.

Subtemporal Approach vs. Pterional Approach in Basilar Bifurcation Aneurysms: 2 Case Reports

Two patients with basilar bifurcation aneurysm were treated by different approach, low lying posteriorly projecting aneurysm was clipped with subtemporal approach and high bifurcated basilar bifurcation aneurysm with multiplicity approached through pterional method. The author reviewed literature concerning the approaches of basilar bifurcation aneurysm.

Aneurysms Arising from the Hemispheric Branch of the Superior Cerebellar Artery and PI Segment of the Posterior Cerebral Artery

The authors are reporting aneurysms arising from the hemispheric branch of the superior cerebellar artery(SCA) and PI segment of the posterior cerebral artery(PCA). These aneurysms were discovered after a subarachnoid hemorrhage(SAH). While attempting to make the proper placement of a clip at the aneurysmal neck of the P1 sement of the PCA aneurysm through the left subtemporal approach, because of kinking of the posterior thalamoperforating arteries, the clip repositioned and the remaining part of the aneurysmal neck was wrapped with fibrin glue soaked muscle. The case of an aneurysm arising from the hemispheric branch of the SCA was treated with proper clipping of the aneurysmal neck through the left subtemporal approach with a small division of the tentorium. After reviewing literature, we want to stress the rarity of these aneurysms and discuss the method of surgical approach for such aneurysms arising at the P1 segment of the PCA and the distal SCA.

Giant Serpentine Aneurysm of the Posterior Cerebral Artery: Case Report

Aneurysms of the posterior cerebral artery are rare, furthermore giant serpentine aneurysms-partially thrombosed aneurysms containing a tortuous vascular channel-of the posterior cerebral artery are extremely rare. The author et al. were able to remove 3.9cm x 2.9cm x 3.0cm sized giant serpentine aneurysm of the distal PCA totally, without any significant postoperative neurological sequela except transient ipsilateral third cranial nerve paresis and transient hemihypesthesia. Various kinds of surgical treatment were proposed by several authors in managing unclippable giant aneurysms:excision including partial excision;clipping of feeding artery and excision;trapping and excision;revascularization and excision;anastomosis only. We took subtemporal approach under the surgical microscope and trapping & excision was performed in several steps:proximal clipping of the PCA distal to the Pcom-PCA junction;reducing volume of the mass through piecemeal resection of the aneurismal wall;distal clipping of the PCA;total excision and final trapping just proximal and distal to the origin of the aneurysm. We are discussing the characteristics of the giant serpentine aneurysm, precognition of rich collateral circulation of the PCA distal to trapping and surgical management of the giant serpentine aneurysm.

Subtemporal Approach for Basilar Bifurcation and Basilar-Superior Cerebellar Artery Aneurysms

The pterional(Transsylvian) and subtemporal approaches are main surgical route for direct clipping of basilar bifurcation and basilar-superior cerebellar artery aneurysms. In general , the pterional approach has the advantage for high placed aneurysm and the subtemporal approach has the advantage for low placed and posterior directed aneurysm of basilar bifurcation. The authors has been performed surgery for 5 cases of basilar bifurcation and basilar-superior cerebellar artery aneurysms through subtemporal route during 1.5 years with good results in 3 cases, fair result in 1 case, and death in 1 case. We described about this 5 cases detaily and discussed the subtemporal approach for these lesions.