A 24-year-old woman was taken to an outside hospital by emergency medical personnel after she was found unconscious on the bathroom floor by her husband. On arrival at the hospital, the patient was somnolent but able to move all extremities. Computed tomography (CT) scan of the head showed intraventricular hemorrhage associated with mild ventriculomegaly. A ventriculostomy was performed before cerebral angiography. Angiographic injection of the left vertebral artery showed an ~8-mm anteriorly directed basilar trunk aneurysm at the level of the AICAs (Fig. 1A
). The right AICA originated from the inferolateral aspect of the aneurysmal wall. A focal area of stenosis was present in the basilar artery just proximal to the aneurysm.
Figure 1 (A) Anteroposterior and (B) lateral angiographic views of the head. The left vertebral artery injection shows an 8-mm, anteriorly directed basilar trunk aneurysm at the level of the AICA. (Used with permission (more ...)
The patient had a complicated medical history. Seven years before this event at the age of 16, she was diagnosed with human immunodeficiency virus (HIV). At presentation, the patient's CD4 count was 17μ3. She was on lopinavir/ritonavir and lamivudine/zidovudine. She was also on empiric antibiotic prophylaxis with trimethoprim/sulfamethoxazole and aztreonam. Four years later she was diagnosed with AIDS. Her opportunistic infection, coccidioidomycosis meningitis, proved to be refractory to treatment. She failed treatment with fluconazole and voriconazole. At the time of her intracranial hemorrhage, she was on salvage therapy with posaconazole and amphotericin B.
Her hematocrit was 23 and creatinine was 1.5 mg/dL. The anemia was attributed to the AIDS and lamivudine/zidovudine therapy. Renal insufficiency was thought to be related to amphotericin B therapy. Serum human chorionic gonadotropin was positive for pregnancy. Transvaginal ultrasonography showed a viable 13-week fetus.
At cerebral angiography, the basilar trunk aneurysm was interpreted as a dissecting mycotic aneurysm. The right AICA, which arose from the side wall of the aneurysm, appeared to be in significant jeopardy if coiling were attempted. The decision was thus made to treat the aneurysm surgically.
On posthemorrhage day 2, the patient underwent a right retrosigmoid craniotomy. Once the thickened arachnoid was opened, we encountered numerous nodules of thickened purulent material. The avenue of approach was between the seventh and eighth cranial nerve complex and the lower cranial nerves. A large thin-walled aneurysm was visualized at the basilar trunk. During dissection of the aneurysm at the neck, we caused a small tear that was easily controlled with a piece of Surgicel (Ethicon, Somerville, NJ) and mild compression. At this point, because of the friable appearance of this mycotic aneurysm and because of our intraoperative assessment that we lacked adequate proximal control, we decided to perform the remainder of the aneurysm dissection under hypothermic cardiac standstill.
The patient was fully heparinized. The cardiothoracic surgery team cannulated the femoral artery and vein to prepare for cardiopulmonary bypass. The patient's core temperature was decreased to 18°C. Once the patient's body temperature reached 18°C, the cardiopulmonary bypass was stopped and the blood was drained from the venous side into the reservoir. Immediately, the intravascular space, including in the basilar artery, was decompressed. We then resumed dissection of the aneurysm wall, which was significantly deflated. The aneurysm was clipped successfully with a 7-mm slightly curved clip and a 9-mm straight clip. On visual inspection the right AICA appeared to be kinked but patent. However there was inadequate space to confirm patency by Doppler ultrasonography or indocyanine green angiography.
The patient was under cardiac standstill for 6 minutes and 23 seconds. Blood flow was then gradually increased to full capacity while the patient was rewarmed simultaneously. Once the mixed venous temperature reached 36°C, the cardiopulmonary bypass was slowly weaned. Once the cannulas were removed, the patient was transfused with fresh-frozen plasma and platelets. The heparin was reversed with 30 g of intravenous protamine. After meticulous hemostasis was obtained, the craniotomy was closed. Per infectious disease recommendation, an Ommaya reservoir was left in the posterior fossa with the tip of the catheter in the cisternal magna before closure.
Postoperative cerebral angiography showed no residual aneurysm. The basilar trunk was mildly narrowed, but the right AICA was occluded completely (Fig. 2A
Figure 2 (A) Anteroposterior and (B) lateral angiographic views the head. The left vertebral artery injection shows no residual aneurysm. The basilar trunk is mildly narrowed, but the right AICA is occluded completely. (Used (more ...)
After surgery, the patient moved all extremities spontaneously but did not follow commands. Immediately after surgery, transvaginal ultrasonography confirmed viability of the fetus. The patient, however, underwent a spontaneous abortion on postoperative day 6. She spent 10 days in the intensive care unit. During her hospitalization, the patient's neurological status improved progressively.
On postoperative day 19, the patient was discharged home under 24-hour family supervision with home physical and occupation therapy. At her last follow-up 7 months after surgery, the patient was neurologically intact. Her only complaint was of intermittent headaches. She was on intrathecal amphotericin B twice weekly as well as voriconazole, efavirenz, and lamivudine/zidovudine. Despite this regimen, the patient's coccidioidomycosis meningitis has proven extremely refractory to treatment. Per infectious disease recommendations, she is currently scheduled to undergo placement of an intrathecal pump for continuous infusion of intrathecal amphotericin B.