We successfully clipped a right VA-PICA aneurysm through the transcondylar fossa approach. The usefulness of this approach is reported.
A 66-year old female was admitted because of moderate headache, nausea and vomiting. CT scan showed subarachnoid hemorrhage particularly in the cisterns of the right posterior fossa. Vertebral angiography revealed a right VA-PICA aneurysm located 5.3mm apart from the midline and 6mm inferior to the internal auditory meatus. Direct clipping was done through the transcondylar fossa approach. A straight clip was applied through the space between the vagus and hypoglossal nerves. Postoperative hypoglossal nerve palsy and hoarseness disappeared within a week. The postoperative angiography revealed complete obliteration of the aneurysm.
The transcondylar fossa approach differs from the transcondylar approach. In the transcondylar fossa approach, the condylar fossa and jugular tubercle are extradurally drilled. The occipital condyle is kept intact so that the atlanto-occipital joint movement is well preserved. This approach is very useful for VA or VA-PICA aneurysm, giving a wider operative field and closer access.

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Although new mini aneurysm clips have become available recently, a certain type of small neckless cerebral aneurysm remains unclippable and is generally treated by coating or wrapping. Large cerebral aneurysms are sometimes difficult to clip because of clip slippage.
We tried a new technique with topical application of plastic adhesive directly to the aneurysm sac to make an unclippable aneurysm clippable. When the aneurysm is dissected free and about to be clipped, a small drop of cyanoacrylate adhesive (Aron alpha A^®) is applied to the wall of the sac with an elastic needle. As the cyanoacrylate hardens in less than two minutes, once dried, the clip can be applied without risk of slippage.
(1) If the clip slips off the small neckless hemispheric-shaped aneurysm, applying a small drop of Aron alpha A^® to the fundus of the aneurysm makes it clippable.
(2) When there is incomplete obliteration of the aneurysmal sac, additional clipping becomes feasible after topical application of Aron alpha A^® allowing satisfactory clipping of the remaining aneurysm.
(3) In clipping a rather large aneurysm, slippage of the clip is not uncommon. A small amount of Aron alpha A^® applied to the wall of the sac prevents the clip from slipping.
(4) For aneurysmal clipping of a large aneurysm body, our technique is helpful to ensure adequate clipping to preserve the artery, to avoid stenosis of the parent artery as well as occlusion of other arterial branches. Only the aneurysmal body is obliterated by clipping without slippage.
(5) Further applications of our method would include giant aneurysm of the internal carotid artery to form arterial wall, and clipping with large fenestrated clips to prevent slipping and to facilitate ideal clipping.
In any case, if the placement is unsatisfactory, reclipping was not difficult in our trial. Clipping of an aneurysm is the optimal surgical therapy and is well accepted by all neurosurgeons. Our method may be helpful in aneurysmal surgery.

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We describe our modified subtemporal approach for basilar terminal aneurysms. We have modified the conventional subtemporal approach to diminish temporal lobe retraction and the risk of damage to the temporal lobe. The surgeon stands at the dorsocaudal side of the patient's head and the operative microscope is introduced posterolaterally to the patient's head. The posterior part of the temporal lobe is slightly retracted upward anterior to the vein of Labbé. The tentorium and arachnoid are cut, and the cerebrospinal fluid is aspirated as much as possible. Thus the brain becomes slack at the initial stage of the operation. The operative microscope is positioned parallel to the inclination of the tentorium or temporal base. The basilar terminal vasculatures can be examined upward from below with minimal temporal lobe retraction and the aneurysm is clipped. The perforating arteries arising from the terminal portion of the basilar artery are well recognized in this modified approach.

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Surgical resection of 15 operatively obscure arteriovenous malformations (AVM's) was accomplished with the assistance of intraoperative angiography, which was performed stereo-graphically to provide three-dimensional orientation and was repeated until total resection of the AVM was confirmed. All films obtained were subtracted to improve clarity. The method presented here may be useful for the resection of all types of AVM. Only two patients had residual AVM after the initial operation. No complications attributable to angiography were noted.

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We discuss surgical treatment of pericentral AVM near the central sulcus. We treated 33 patients have been treated in our clinic; they can be classified into four subtypes: operculofrontal AVM (9 cases), dorsolateral AVM (8 cases), parasagittal AVM (11 cases), and giant AVM involving sensorimotor cortices (5 cases).
In all surgically treated patients with operculofrontal AVM or dorsolateral AVM, nidi were totally removed and permanent morbidity was 6%.
On the other hand, complete obliteration was usually difficult for parasagittal AVMs. Among 6 patients with surgically-treated parasagittal AVM, transient paralysis was found in 3 (50%) and permanent morbidity was observed in 1 (17%). Among 4 patients with parasagittal AVM who were treated by embolization therapy alone, transient paralysis was found in 3 (75%) and permanent morbidity was recognized in 2 cases (50%). In each case, the nidi could not be completely obliterated. Among 4 patients with giant AVM who were palliatively treated by feeder ligation or by partial embolization, rebleeding was found in 2 cases (50%). Thus, palliative procedure could not prevent recurrent hemorrhage. A more conservative attitude is therefore recommended for giant AVM involving sensorimotor cortices.

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Introduction of microsurgery for cerebral aneurysms markedly improved the operative outcome. However, the microsurgically blind portion hidden behind unretractable structures such as a major artery, cranial nerves, aneurysm sack and tentorium, has remained a problem. An endoscope was applied for microsurgical operation of cerebral aneurysm to minimize the blind area under the microscope.
We used a rigid form endoscope (CODMAN Gaab Neuroendoscope System with 30°, 70°and 120°angled telescope) to visualize the microsurgically blind portion in 10 patients with cerebral aneurysms. Application of endoscope was useful to reduce the risk of careless surgical injury by avoiding the extensive brain retraction in all patients. We report here on four patients. In 1 patient with high positioned basilar top aneurysm (Case 1), the aneurysm could not be visualized through pterional route, and after confirmation of the aneurysm by endoscope, neck clipping was performed through orbitozygomatic route. For bilateral internal carotid artery (IC) aneurysms (Case 2), after clipping of the left IC-posteior communicating artery (PcomA) aneurysm, the IC aneurysms on the right side could be inspected endoscopically through the prechiasmatic cistern. In another patient (Case 3), during endoscopic observation for left IC-PcomA aneurysm, IC-anterior choroidal artery aneurysm that had not been identified by angiography was detected. In the remaining patient (Case 4), an endoscope was used to confirm correct neck clipping for a vertebral artery-posterior inferior cerebellar artery aneurysm attached to the seventh and eighth cranial nerves.
Though instruments of solid form endoscope entail some inconvenience for endoscopic surgery, the image is markedly clearer than that of the fiberoptic endoscope. Endoscopy seems to be useful for minimizing the surgical trauma in microsurgical operation for cerebral aneurysm.

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During the four years between 1992 and 1995, we treated 17 cerebral aneurysms with severe atherosclerosis around them. Nine of the cases were operated without any measure for severe atherosclerosis (non-reinforcement group). But recently, 8 cases were clipped after reinforcement for the aneurysmal neck using Surgicel^® and Biobond^® (reinforcement group).
In the non-reinforcement group, 3 cases were clipped with a temporary clip, 1 was treated with multiple clipping, and 5 were treated with a single clip. Of the 5 single clippings, 2 had residual necks. The other 2 cases were treated with dome clipping and neck coating.
In the reinforcement group, 1 case was treated with a temporary clip, 2 were treated with multiple clipping, and 5 were treated with a single clip. There were no residual neck and coating methods.
In the non-reinforcement group 4 cases experienced intraoperative ruptures, 1 slipping out of the clipping, and 1 injury of the parent artery. In the three intraoperative rupture cases, the wall between aneurysmal neck and atherosclerotic lesion was split by the clip. However, there was only 1 case of perforating artery injury in the reinforcement group. Histopathological findings about the aneurysmal neck with atherosclerosis around them show a frail portion between the aneurysmal wall and atherosclerotic lesion.
In conclusion, the reinforcement technique for aneurysmal neck with severe atherosclerosis might be useful to prevent the neck splitting and slipping out of clips.

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Five patients with small ophthalmic segment aneurysm arising from the postero (infero)-medial wall of the internal carotid artery were operated on through a contralateral pterional approach. Based on the angiographic and operative findings, the generation of the aneurysms in this location was examined with reference to the origin of the superior hypophyseal artery (SHA).The aneurysm necks were less than 7 mm in size and located a little distal to the origin of the ophthalmic artery. Through the contralateral approach after securing the internal carotid artery at the neck, dissection and clipping of the aneurysms were performed without difficulty. The SHA was clearly recognized in close proximity to the aneurysm in every patient. However, the SHAs were so fine and intimately related with aneurysms that it was impossible to preserve them in 3 patients. Postoperative recoveries were uneventful in all of the patients, though the internal carotid artery was occluded at the aneurysmal clip in 1 patient in whom nasal lower quadrant anopsia in the ipsilateral eye remained.
The operative findings revealed that the SHA originated from the posteromedial wall of the internal carotid artery just proximal to an aneurysm in 4 cases and from the medial wall a little apart from aneurysm in 1 case. The SHAs ran posteriorly around the aneurysmal dome and uniformly terminated in 2 branches, 1 to the inferior aspect of the optic nerve and chiasma, another to the pituitary stalk. These findings indicate the aneurysms are generated mainly based on a vulnerability of the arterial wall at the crotch of the SHA rather than a hemodynamic stress, and support the terminology 'superior hypophyseal artery aneurysm' for the aneurysms in this location.
Clinically, neither pituitary dysfunction nor visual disturbance was caused by an operative occlusion of the unilateral SHA in almost all the reported cases of ophthalmic segment aneurysms, including the present cases. Abundant arterial anastomoses in the suprasellar region as were demonstrated in detail by Marincovic et al. may account for the favorable surgical results. Thus, at the operation of ophthalmic segment aneurysms projecting posteromedially, surgeons should concentrate on complete neck clipping without being overcautious in preserving the superior hypophyseal artery.

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We report an aneurysm that developed at the superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis. A 52-year-old woman, who had a history of subarachnoid hemorrhage (SAH) 10 years before, was admitted with headache. At the previous SAH, 3 cerebral aneurysms were identified and 2 of them were successfully treated with neck clipping. The remaining right internal carotid giant aneurysm was treated with the proximal occlusion of the right internal carotid artery following the right STA-MCA anastomosis. She had gone well without neurological deficit until the current admission. CT scan on admission revealed intracerebral hemorrhage in the right frontal region. Angiography disclosed a saccular aneurysm at the site of the anastomosis. The aneurysm was successfully treated by neck clipping. The intraoperative findings showed that the aneurysm raised from the MCA wall opposite to the STA orifice. Histological examination of the aneurysm wall indicated a true aneurysmal formation. Congenital factors, as suggested by her history of multiple aneurysms, and hemodynamic stress to the recipient artery may have contributed to the aneurysm development.

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We report the case of a 59 year-old female who had a stump of middle cerebral artery occlusion mimicking a ruptured aneurysm. She was admitted to to our hospital. A computed tomography scan showed moderate subarachnoid hemorrhage (SAH) in the left Sylvian fissure. From preoperative neuroradiological findings, it was suspected that an aneurysm with a cylinder-like dome occurred at the bifurcation of the left middle cerebral artery (MCA) with occlusion from the beginning of left superior trunk of MCA and then ruptured.
In operation, however, an aneurysm was not found anywhere. An aneurysmal opacification on preoperative angiograms proved to be a stump of the occluded superior trunk. The cause of SAH was unknown. She was discharged about 1 month later without any neurological deficits. The cylinderlike dome on preoperative angiograms may suggest a stump of an occluded artery.

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We treated a 55-year-old woman who suddenly developed severe headache, which was followed by disturbance of consciousness. Her previous medical history included cerebral infarction at 50. Since then, she had had dementia, which was symptomatically severe and been under treatment at home. On admission to our hospital, head CT showed subarachnoid hemorrhage with a hematoma in the right fissure of the Sylvius. Cerebral angiography revealed an aneurysm arising peripherally from the right middle cerebral artery partly with abnormal hypervascularity of moyamoya-like disease. In addition, the left internal carotid artery was peripherally completely obliterated. Abnormal vascularity grew extensively distal to the obliteration.
On the day when the patient experienced the headache, the neck of the ruptured aneurysm was clipped. Because severe persistent disturbance of consciousness remained, she was referred to a local medical facility afterwards. The resected cerebral aneurysm was histologically examined. Because such a structure as seen in common aneurysmal walls was completely lost leaving necrotic tissue, this aneurysm was false. Because the lesion of moya-moya disease was small with predominant normal arteries in the area supplied by the right internal carotid artery, the bleeding artery would have been prone to receive hemodynamic stress. The false aneurysm may have been formed at the site where the arterial wall was weak.

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