Faculty Bibliography

OBJECTIVE: To compare cost-effectiveness of different strategies for completion angiography after cerebral aneurysm clipping. METHODS: A literature search was used to determine the outcome probabilities and costs of various strategies. The pooled results were used in a Markov cost-effectiveness model to compare quality-adjusted life-years and costs of each strategy. Sensitivity (threshold) analyses and Monte Carlo simulation were used to test variation in the model. RESULTS: Routine (for all cases) intraoperative angiography proved to be slightly more cost-effective than selective (only for cases deemed 'high risk') intraoperative angiography, being both less costly and more effective. Routine postoperative angiography was the least cost-effective. However, in centers whose rates of clip-induced arterial compromise are much lower than the averages reported in the literature, selective angiography might be warranted. CONCLUSION: Routine intraoperative angiography remains the most cost-effective form of completion angiography after aneurysm clipping, at least at our present state of technology

OBJECTIVE: The role of intraoperative angiography (IA) in the surgical treatment of cerebral aneurysms has remained extremely controversial. We determine the frequency and predictors of unanticipated findings necessitating clip adjustment established on postoperative angiography (PA) in a consecutive series of 147 aneurysms. On the basis of published series, we discuss the utility, safety, accuracy, and cost effectiveness of adjunct IA in the surgical treatment of cerebral aneurysms. METHODS: We retrospectively examined the charts of 124 consecutive patients harboring 147 aneurysms that were surgically clipped between December 2000 and March 2005 and had PA available for review. Patient demographics, aneurysm size, location, Hunt and Hess score, Fisher grade, mode of aneurysm discovery, time between discovery and surgery, and PA results, as determined by a blinded independent neuroradiologist, were recorded. RESULTS: PA demonstrated two (1.4%) unexpected residuals, four anticipated residuals (2.7%), and four (2.7%) vessel compromises. Of the six unanticipated outcomes, two of two (100%) unexpected residuals and three of four (75%) vessel compromises were from large aneurysms (P = 0.0001 each). Middle cerebral artery aneurysms comprised 5 of 10 (50%) imperfect outcomes (three expected remnants and two vessel occlusions), which trended toward significance (P = 0.06). CONCLUSION: IA is recommended during the surgical clipping of complex or large aneurysms and some middle cerebral artery aneurysms. High cost-benefit ratio, false-negative rate, and moderate risk, however, preclude routine use. With future technological advances, IA may warrant broader use by replacing postoperative studies in the neurosurgical management of intracranial aneurysms

The authors report a case of preoperative embolization and resection of a choroid plexus papilloma of the lateral ventricle in a 4-month-old boy. These vascular tumors of the central nervous system present a significant intraoperative bleeding risk. Attempts at preoperative embolization to reduce the bleeding risk have rarely succeeded because of the small and tortuous vessels feeding these tumors in infants. The case presented here supports the feasibility of preoperative embolization as a therapeutic adjunct in infants

Cerebral vasospasm remains a serious complication of aneurysmal subarachnoid hemorrhage. Efforts in improving its clinical outcome have been focused on early diagnosis and applying effective treatment regimens. Standard diagnostic modalities currently used do not fully address this complex disease. The use of CT angiography and CT perfusion are discussed, with emphasis on its potential role in not only detecting vasospasm, but also in guiding management decisions and assessing clinical outcome

Cerebral vasospasm is a major cause of morbidity and mortality associated with subarachnoid hemorrhage (SAH). Advances in neuroimaging and development of newer intraparenchymal monitoring devices have improved the prediction and diagnosis of cerebral vasospasm significantly. Recent experimental and clinical trials have increased the armamentarium of preventive and treatment strategies for cerebral vasospasm. Vasospasm refractory to medical therapy usually is treated endovascularly with percutaneous transluminal balloon angioplasty (PTA) for proximal vessel vasospasm and vasodilator infusion for distal vessel vasospasm. Although vasospasm usually does not recur after PTA, recurrence is frequent after vasodilator infusion. The development of newer microballoon catheters has led to improvements in treatment of not only proximal but also distal vessel vasospasm with balloon angioplasty. This article reports on current knowledge in the diagnosis, prediction, prevention, and management of cerebral vasospasm

OBJECTIVE: The outcomes reported in the International Subarachnoid Aneurysm Trial (ISAT), a multicenter, prospective, randomized trial to directly compare surgical clipping with endovascular coiling as treatments for ruptured intracranial aneurysms, have been misinterpreted by many to indicate the superiority of coiling to surgical clipping in all instances. To better understand the results of ISAT and their implications for practice patterns, we compared the ISAT results with the results of other published studies regarding the treatment of ruptured intracranial aneurysms. METHODS: Data from 19 published studies were compared with each other and with ISAT results. Outcomes examined were overall rates of mortality, rebleeding, poor outcome (disability and death), procedural complication rates, and rates of reoperation and nontotal occlusion. RESULTS: In the 19 published studies, mean procedural complication rates were similar (surgical clipping, 11%; endovascular coiling, 9%); ISAT did not report procedural complications. ISAT rates were within the range of the other studies for overall mortality, total rebleeding, and poor outcome. Reoperation rates in the other studies were similar to those of ISAT (endovascular coiling, 12.5%; surgical clipping, 3.4%). The ISAT rate for less than 100% occlusion for endovascular coiling (6%) was below the range in the other studies (8.3-70.4%). CONCLUSION: Discrepancies with the results of other published studies, procedural limitations in study design, and lack of some data endpoints and subgroup analysis raise concerns regarding extracting generalizations from the conclusions of ISAT. We think that the creation of a national registry would further the study of treatment of ruptured intracranial aneurysms

Wide-necked aneurysms remain difficult to treat by either open microneurosurgical or endovascular procedures. Recent advances in the latter technology, including intracranial stents and bioactive coils, now allow an endovascular treatment option for cases in which this was not previously available. In this report the authors describe the new developments in endovascular technologies that make the treatment of wide-necked aneurysms possible. This includes discussion of intracranial stents and bioactive coils designed to promote obliteration of the aneurysm lumen. In addition, methods for coil insertion in wide-necked aneurysms are described, including balloon remodeling and various stent placement procedures. Wide-necked aneurysms previously thought to be untreatable by endovascular means can now be obliterated, thanks to new devices specifically designed for intracranial use

Mechanical embolectomy in acute ischemic stroke employs the use of novel endovascular devices to revascularize occluded intracerebral arteries. Devices like the Merci Retiever and other endovascular snares, laser thrombectomy and rheolytic/obliterative microcatheters, intracranial balloon angioplasty and stenting, and intra-arterial and transcranial ultrasound-enhanced chemical thrombolysis are intended to improve tissue rescue and diminish reperfusion hemorrhage while broadening the population eligible for therapy. Patient selection with MRI- and CT-based stroke protocols can detect tissue at risk and may obviate the classic limitations of the stroke therapeutic time window. These devices are being developed and modified at a rapid pace, requiring mounting endovascular expertise, and are being used successfully alone or in conjunction with chemical thrombolysis with relative safety

Recent advancements in endovascular aneurysm repair, including bioactive and expansile coils and intracranial stents, hold promise for improved aneurysm occlusion rates. We report the immediate and midterm clinical and angiographic outcomes of a consecutive series of patients treated since the advent of these technologies. Clinical and radiological records of 134 patients with 142 aneurysms treated between 2001 and 2004 were retrospectively evaluated by an independent neurologist. Endovascular procedures were analyzed by an independent neuroradiologist blinded to all clinical information. Seventy-two ruptured and 60 un-ruptured saccular aneurysms, nine fusiform and one post-traumatic aneurysm were treated. Matrix coils were used in 53% of saccular aneurysms and HydroCoils in 13% of all aneurysms. Neuroform stents were deployed in 19% of aneurysms. Angiographic total or subtotal occlusion was achieved in 76% of cases and in 96% at last follow-up. Aneurysm recanalization was observed in 14% over a mean follow-up of 12 months, and 18% of aneurysms were retreated. Clinically relevant complications occurred in 6.0%, resulting in procedure-related morbidity of 0.6% and 0.6% mortality at 6 months. No aneurysm bled over a cumulative 1,347 months of observation. Newer embolization technologies can be exploited successfully even in more complex aneurysms with very low morbidity and mortality

BACKGROUND: Capillary hemangiomas are benign vascular lesions that commonly present at birth or in early infancy on the face, scalp, back, or chest. The authors present an exceedingly rare case of an intracranial capillary hemangioma arising in an adult. Only 4 biopsy-proven cases have been reported in the pediatric population previous to this case report. CASE DESCRIPTION: A 31-year-old pregnant woman presented at 38 weeks of gestation with severe headaches, nausea, and vomiting. Imaging revealed an extra-axial mass lesion arising from the tentorium with both supra- and infratentorial components. The patient underwent a resection of her tumor, which was diagnosed as a capillary hemangioma by histopathologic examination. The patient required 2 further resections after the lesion exhibited a rapid regrowth from residual tumor in the left transverse sinus. The patient has remained free of disease 41 months out from her third surgery. CONCLUSIONS: Intracranial capillary hemangiomas are exceedingly rare entities, with a capability for rapid growth. When gross total resection cannot be achieved, these patients should be observed closely, and the use of adjuvant radiotherapy should be considered