✓ Failure to obliterate intracranial aneurysms completely during initial surgery still occurs in spite of recent technical advances. Of the 115 reoperations reported in this series, 89% of the aneurysms were obliterated, and 84% of the patients had a satisfactory outcome. Twelve patients had poor results, three (2.6%) of whom were in poor condition before reoperation.
Reoperation in 115 cases
Charles G. Drake, Allen H. Friedman and Sydney J. Peerless
Jonathan E. Hodes, Allan J. Fox, David M. Pelz and Sydney J. Peerless
✓ Three cases of complex aneurysms are presented in which balloon embolization therapy was associated with subsequent aneurysmal rupture, causing subarachnoid hemorrhage in two cases and a carotid-cavernous fistula in one. Two of these patients were treated directly by balloon embolization following surgical exploration. The third patient developed the fistula during postembolization volume expansion and heparinization.
Charles G. Drake and Sydney J. Peerless
✓ The paucity of information about giant fusiform intracranial aneurysms prompted this review of 120 surgically treated patients. Twenty-five aneurysms were located in the anterior and 95 in the posterior circulation. Six patients suffered from atherosclerosis and only three others had a known arteriopathy. The remaining 111 patients presented with aneurysms resulting from an unknown arterial disorder; these patients were much younger than those harboring atherosclerotic aneurysms. Mass effect occurred in only 50% of cases and hemorrhage in 20%. Eight aneurysms caused transient ischemic attacks. Hunterian proximal occlusion or trapping were dominant among the treatment methods. In contrast to the management of giant saccular aneurysms, the usual thrombotic occlusion of a giant fusiform aneurysm after proximal parent artery occlusion requires the presence of two collateral circulations to prevent infarction, one for the end vessels and another for the perforating vessels that arise from the aneurysm. Although there was some reliance on the circle of Willis and on collateral vessels manufactured at surgery, the extent of natural leptomeningeal and perforating collateral, thalamic, lenticulostriate, and brainstem vessels was astonishing and formerly unknown to the authors. Good outcome occurred in 76% of patients with aneurysms in the anterior circulation; two of the six cases with poor results included patients who were already hemiplegic. Ninety percent of patients with posterior cerebral aneurysms fared well. Only 67% of patients with basilar or vertebral aneurysms had good outcomes, although more (17%) of these patients were in poor condition preoperatively because of brainstem compression.
Beverly J. Rice, Sydney J. Peerless and Charles G. Drake
✓ With the ever-increasing number of intact aneurysms revealed by modern imaging, the options for their management are assuming great importance. While some knowledge has emerged as to their natural history and the results of surgical treatment of those in the anterior circulation, little information has been published concerning unruptured aneurysms arising from the posterior circulation. The authors report their experience since 1971 with 167 patients operated on for 179 unruptured vertebrobasilar aneurysms up to 25 mm in diameter. Overall, 160 aneurysms were treated by direct clip obliteration, while 19 were managed by alternative methods. Fifty-three patients (32%) had solitary aneurysms and the other 114 patients (68%) had multiple aneurysms or an associated arteriovenous malformation, which were commonly treated concurrently. Many of these coexisting vascular anomalies had ruptured in the recent or remote past, adding to the complexity of management and interpretation of specific surgical results related to the intact posterior circulation aneurysm.
There were 78 documented postoperative complications including 23 systemic complications, seven postoperative hematomas, six brain injuries from retraction, five cases of aseptic meningitis, three instances of seizures, three wound infections, and three patients with hydrocephalus. Multiple complications occurred in 23 patients. Seventy-one of the patients with these untoward events recovered, without disability, with time or treatment.
There were only six poor results and one death in the series, resulting in a 4.2% combined morbidity/mortality rate. However, since two of these poor outcomes and the single death were attributable to a coexisting aneurysm, the actual surgical morbidity related specifically to the posterior circulation aneurysm was only 2.4%. This experience suggests that non-giant, intact vertebrobasilar aneurysms can be obliterated surgically at a very low risk, and this treatment should eliminate the greater lifetime risk related to an unsecured aneurysm.
Experience with 20 cases
Fernando Viñuela, Allan J. Fox, Gerard M. Debrun, Sydney J. Peerless and Charles G. Drake
✓ Sixty-five carotid-cavernous fistulas were studied at University Hospital, London, Canada, from 1978 to 1982, 20 of which fulfilled the clinical and angiographic criteria of a spontaneous carotid-cavernous fistula. Of these 20 fistulas, 17 were unilateral, and three were bilateral. In 18 cases the angiographic findings were typical of an arteriovenous malformation (AVM), and in two a ruptured giant intracavernous aneurysm was found. These patients were treated according to whether they had a nonresolving or progressive cavernous sinus syndrome or deterioration of vision. The cavernous dural AVM's were treated with polyvinyl-alcohol and/or isobutyl-2-cyanoacrylate (IBCA) embolization of the external carotid artery blood supply. Two patients underwent postembolization surgical procedures. The detachable balloon technique was used to occlude the fistulas associated with the two giant ruptured intracavernous aneurysms and a small dural intracavernous AVM. Eight patients received no therapy; in two, spontaneous obliteration of the fistula occurred. Of the nine cavernous AVM's embolized with particles and/or IBCA, successful transvascular embolization was achieved in seven cases, and partial embolization followed by surgery in two cases. Successful balloon obliteration of the giant intracavernous ruptured aneurysm was obtained in two cases. In one patient, right hemiplegia with aphasia resulted from reflux of IBCA emboli through the artery of the foramen rotundum into the left middle cerebral artery.
Charles G. Drake, Allan H. Friedman and Sydney J. Peerless
✓ The authors report their treatment of 66 infratentorial arteriovenous malformations (AVM's) in patients aged 5 to 69 years. Sixty-one of them presented with hemorrhage, three with headache, and two with focal neurological deficits. Five patients underwent surgical exploration only, one was treated with ventriculostomy, three had ligation of the AVM feeding arteries, four underwent intraoperative embolization, and two had pontine hematomas removed; complete excision was attempted in 51 patients and accomplished in 47. Twelve of the patients also had aneurysms (nine of which had ruptured). Of this series, 71% had a good result, 14% a poor result, and 15% died. Most of the operative morbidity was due to massive postoperative hemorrhage, probably related to inadequate hemostasis.
Immediate results and long-term outcome in 201 patients
Gary K. Steinberg, Charles G. Drake and Sydney J. Peerless
✓ Deliberate occlusion of the basilar or vertebral arteries was performed in 201 patients with intracranial aneurysms, where the aneurysmal neck could not be clipped directly. The aneurysms arose from the basilar apex in 83 cases, the basilar trunk in 46, the vertebrobasilar junction in 35, and the vertebral artery in 37; 87% of the aneurysms were classified as giant lesions (> 2.5 cm). There were 85 upper basilar occlusions, 41 lower basilar occlusions, 29 bilateral vertebral occlusions, and 48 unilateral vertebral artery occlusions. The clinical follow-up period varied from 1 to 23 years, with a mean of 9.5 years. Overall long-term results were excellent in 68% of the patients, good in 5%, and poor in 3%; 24% died. Clinical outcome varied according to aneurysm site; excellent or good results were achieved in 64% of the patients with basilar apex, 76% with basilar trunk, 74% with vertebrobasilar junction, and 87% with vertebral artery aneurysms. Clinical outcome also varied depending on preoperative grade: 86% of the patients with an excellent presenting grade achieved excellent results. The size of the posterior communicating arteries was a good predictor of tolerance to basilar artery occlusion (p < 0.05). Successful aneurysm thrombosis was achieved in 78% of the patients.
The neurological status in 26 patients (13%) deteriorated due to vertebrobasilar ischemia occurring within the 1st postoperative week, and thrombosis or embolism was implicated much more frequently than hemodynamic insufficiency. Subarachnoid hemorrhage (SAH) in 14 patients, vasospasm in five patients, and surgical trauma in seven patients accounted for additional morbidity in the 1st month following operation; however, many of these patients ultimately made an excellent recovery. Late vertebrobasilar ischemic complications or neurological deterioration from persistent mass effect occurred in 4% of patients with successful aneurysm thrombosis 6 weeks to 18 months after arterial ligation. Among the 43 patients with incompletely thrombosed aneurysms, 67% developed early or late neurological deterioration from SAH, progressive brain-stem compression, or brain-stem stroke, with 86% of the complications proving fatal.
Franco DeMonte, Sydney J. Peerless and Richard N. Rankin
✓ A 57-year-old woman presented with symptomatic triple tandem stenosis of the left carotid artery. Transluminal angioplasty of an atherosclerotic stenosis at the origin of the common carotid artery was performed retrogradely through a distal arteriotomy after endarterectomy. The postangioplasty effluent was collected and analyzed. Cholesterol crystals and amorphous plaque debris were identified, indicating a source for distal embolization. The clinical significance of this small amount of debris embolizing to the intracranial circulation is uncertain, but should be of concern when considering angioplasty of the cerebral circulation.
Sydney J. Peerless, Juha A. Hernesniemi, Frederick B. Gutman and Charles G. Drake
✓ The authors present a series of 1767 patients with aneurysms of the vertebrobasilar circulation, most of whom were operated on 14 days or more following their last subarachnoid hemorrhage (SAH). Since 1970, 206 patients with vertebrobasilar aneurysms have been surgically treated within 7 days after their last SAH (day of SAH = Day 0). Of patients with a good preoperative grade (Botterell Grade 1 or 2), a good or excellent outcome was obtained in 80% during the first postsurgical month, irrespective of the timing of surgery. All except one of the Grade 5 patients died, and 70% of the Grade 4 patients were significantly disabled or dead. The overall operative mortality rate was the same whether surgery took place in the 1st week after SAH or was delayed. The frequency of rupture of the aneurysm during early surgery was not higher than during late surgery. Thirteen percent of patients developed a delayed ischemic neurological deficit as a consequence of reactive arterial narrowing (vasospasm). The authors recommend early surgery for patients with a good preoperative grade, whose aneurysm does not present a particular technical difficulty because of size, configuration, or location, and occasionally in patients whose lives appear to be in jeopardy because of recurrent hemorrhage.
Charles G. Drake, Sydney J. Peerless and Gary G. Ferguson
✓ Hunterian proximal artery occlusion was used in the treatment of 160 of 335 patients harboring giant aneurysms of the anterior circulation. One hundred and thirty-three of these aneurysms arose from the internal carotid arteries, 20 from the middle cerebral arteries, and seven from the anterior cerebral arteries. Ninety percent of the patients had satisfactory outcomes. The safety of internal carotid artery occlusion has been greatly enhanced by preoperative flow studies and by test occlusion with an intracarotid balloon to identify those patients who require preliminary extracranial-to-intracranial bypass, which was used in all of the middle cerebral occlusions. The anterior cerebral artery had magnificent leptomeningeal collateral flow that prevented infarction even without cross flow. Obliteration of the aneurysm by thrombosis was complete, or nearly so, in all but four patients whose treatment was completed. Analysis of poor outcome in 16 patients revealed that hemodynamic ischemic infarction was known to occur after only two of the carotid occlusions.