Results of microsurgical management of ruptured intracranial aneurysms

Oculomotor nerve palsy in patients with cerebral aneurysms

Twenty-six patients with oculomotor nerve palsy due to cerebral aneurysms were examined. There were six males and twenty females with a mean age of 55 years. 25 of the 26 aneurysms were located at the junction of the internal carotid and the posterior communicating artery and one was at the junction of the basilar artery and the superior cerebellar artery. Twelve patients had associated subarachnoid hemorrhage (SAH); the other 14 did not. The initial symptoms in many patients were ptosis and double vision. Twenty-one of the patients had total oculomotor nerve palsy, one had a sparing of medial rectus muscle; three patients had only ptosis and anisocoria, and one had oculomotor nerve palsy with pupillary sparing. All aneurysms, including giant aneurysms, were clipped under a microscope, and six oculomotor nerves were found to be decompressed at surgery. The follow-up periods were from six months to three years. Nine patients had a complete recovery of oculomotor function; thirteen had an incomplete recovery; and four remained unchanged. The mean interval between the onset of palsy and the time of surgery was 24 days in complete recovery cases, 42 days in incomplete recovery cases, and 119 days in unchanged cases. The recovery of oculomotor function started with the levator palpebrae muscle and followed by the medial rectus muscle. The recovery of pupillary function was, however, not consistent. Of the factors influencing recovery from oculomotor nerve palsy, the interval between the onset of palsy and the time of surgery was most important. Therefore, aneurysms with oculomotor nerve palsy should be operated on as early as possible, regardless of the presence or absence of SAH.

Outcome in elderly patients with ruptured intracranial aneurysm

Sixty-nine elderly patients over 65 years old with ruptured aneurysms had a significantly worse outcome than 192 younger patients with respect to overall management results and operative results (p less than 0.01). The results of an early operation were better in the elderly patients with grade I-III than in those receiving a delayed operation. Concomitant diseases significantly influenced the results in elderly patients (p less than 0.05). It is possible that an early operation results in the better outcome in elderly patients by decreasing the incidence of delayed ischemic complications and preventing rebleeding.

Hemolysate-induced contraction in smooth muscle cells of the guinea pig basilar artery

The hemolysate (10(-5)-10(-2) times dilution; original hemoglobin concentration was 0.83 +/- 0.10 X 10(-3)M) evoked the contraction in a dose dependent manner, and this contraction was composed of low and high sensitive responses as estimated from the Eadie-Hofstee's plot. Indomethacin (10(-7)-10(-5)M) inhibited the latter component in the hemolysate-induced contraction. The membrane potential of smooth muscle cells was -50 mV and the cell was electrically quiescent. The hemolysate (greater than 10(-2) times dilution) depolarized the membrane and increased the ionic conductance of membrane. In rare occasions, the spike potential was triggered on the hemolysate-induced depolarization. The hemolysate (10(-5)-3 X 10(-3) times dilution) produced the contraction with no change in the membrane property. Carbocyclic thromboxane A2 ( cTXA2 ; 2.8 X 10(-10)M) produced the contraction without depolarization of the membrane, yet the TXA2 synthesis inhibitor, OKY-1581 (10(-5)M), had no effect on the hemolysate-induced contraction. PGE1, PGE2 and PGF2 alpha (2.8 X 10(-6)M) produced the contraction with no change in the membrane property. The contraction evoked by 2.8 X 10(-6)M PGF2 alpha corresponded well with that evoked by 3 X 10(-3) times dilution of the hemolysate. Removal of the endothelium by mechanical rubbing modified the hemolysate-induced contraction. Under the assumption that OKY-1581 is a selective inhibitor for TXA2 synthesis, the major part of the contraction (the indomethacin sensitive component) of the basilar artery is postulated to be due to synthesis of the primary PG rather than TXA2 by the hemolysate, yet the hemolysate itself, has to some extent a direct action in evoking the small contraction.