脳動脈瘤術後の再発, 増大, 新生に関する検討

抄録

Study of the recurrence and enlargement of cerebral aneurysms (An) after direct intracranial surgery is important in order to elucidate of the pathogenesis and growth mechanism and to develop more reliable treatment.
By October 1985 a total of 459 cases of An, including three cases of recurrence, one case of enlargement and two of neogenesis had been experienced in our institution, and both analysis of these clinical cases and examination of enlargement factors for 67 infundibular dilatations (ID) from 398 carotid angiograms were made.
The findings obtained are:
1. Two male patients and four female patients averaged 43 years of age at the time of the initial operation and 53 years of age at the time of recurrence.
2. Recurrence and neogenesis were observed 6 to 13 years, averaging 9 years and 10 months, after the initial operation.
3. Multiple An were observed in three cases (3/6) (including 2, 3 and 4 unities, respectively), suggesting extensive fragility of the intracranial artery.
4. In terms of sites of An, ICAn showed the highest incidence [6 unities (6/12) ], followed by MCAn (3 unities), A comm An (2 unities), and ACAn (1 unity).
5. Recurrence detected was ascribable to re-bleeding (4 cases) and follow-up CT (1 case).
6. Use of malleable clip, muscle and the like seemed to be involved in the recurrence, suggesting inadaptability of the clip for the complicated morphology of An and unreliability of the muscle as reinforcement.
7. For four cases (4/6), hypertension was observed in the clinical course, and remarkable changes in blood pressure, i.e., increases in diastolic pressure, especially attracted attention.
8. All cases showed arteriosclerotic changes adjacent to the aneurysm neck to An preoperatively or at autopsy.
9. In four cases the patient returned to work; however one patient died and one remains in a vegetable state. The prognosis for cases of rebleeding is poor.
10. In terms of enlargement factors for ID, statistically significant correlations were observed among the form and size of ID in cerebral angiography, and hypertension, angle of bifurcation for internal carotid artery and posterior communicating artery, degree of development of the latter artery and the like, with very important influences of the hemodynamic stress.
These results suggested that fragility of the vascular wall, unbalance between repair mechanism and hemodynamic stress, and so forth seemed to be responsible for the recurrence and enlargement of An, the prevention of which would require development and selection of clips comfortable to the morphology of An, reliability of reinforcement materials, control of blood pressure, and long-term follow-up observations.