Anatomical Relationship between the Superior Hypophyseal Artery and the Carotid Cave

Interests in the microanatomy of the proximal segment of the internal carotid artery(ICA) have been increased due to the anatomical complexity of this region and the potential sites of the aneurysmal formation. In this study, microanatomical dissections were performed in 70 specimens obtained from 35 formalin-fixed human cadaveric heads to examine the superior hypophyseal arteries(SHAs), ophthalmic artery, and the carotid cave. In our study, 54(77%) carotid caves were presented in 70 specimens. Twenty-five(71%, 50 caves) cadavers harbored the carotid caves on both sides, 4(11%, 4 caves) cadavers only on the one side and the remaining 6(17%) didn't have the caval structure. Total of 162 SHAs which have showen to arise from the medial or posterior aspect of the ophthalmic(C6) segment of the ICA in all cases were identified: 108(67%) arose from the proximal half of the C6 segment and 54(33%) from the distal half. Interestingly, in 54 specimens which had the carotid caves, one to four SHAs arose from the part of the C6 segment within the cave in the 43(80%) specimens. Total number of the SHAs originated within the carotid cave were 51. Sixty-four(91%) of ophthalmic arteries have shown to arise just distal to the distal dural ring on C6 segment, whereas 4(6%) from the clinoid(C5) segment and in 2(3%) cases, the ophthalmic artery arose just at the insertion of the distal dural ring level. The authors describe the microanatomical relationships between the SHA and the carotid cave, and the origin of the SHA and the ophthalmic artery. We hope to get better knowledge of the vascular relationship and the possible mechanism of the SHA aneurysm.

Clinical Significance of Intracranial Hematoma in Ruptured Aneurysms

The intracranial hematoma following cerebral aneurysmal rupture makes patient's clinical status and outcome worse by pressure effect on the brain structure. It's incidence has varied with authors between 5-30% of patients with ruptured cerebral aneurysms. Several authors emphasized the importance of early operation to obtain better results by early removal of hematoma and reducing intracranial pressure. The authors retrospectively evaluated seventy-six patients with intracranial hematomas in 370 patients with ruptured aneurysms from Jan. 1987 to Dec. 1992. The incidence of hematoma resulting from ruptured aneurysm was 20.5%. The most frequent site of aneurysm which was accompanied by intracranial hematoma was the middle cerebral artery, and the next was the anterior cerebral artery. The amount of hematoma and/or evidence of midline shift were the important factors in predicting the clinical outcome. The most favorable outcome was found in cases with intracerebral hematoma only, and the worst was in cases with intracerebral hematoma associated with intraventricular hemorrhage. Fifty out of 76 patients with intracranial hematomas were operated on. Their outcomes were more favorable than in the patients who were not operated on. Aggressive surgical intervention was especially effective in patients with poor Hunt & Hess grades(IV or V) .