Daniel M. Heiferman

Stent-assisted embolization of 100 middle cerebral artery aneurysms

OBJECT The introduction of intracranial stents to aneurysm treatment allows endovascular repair of nearly all aneurysms, but the safety and durability of stent-assisted embolization of middle cerebral artery (MCA) aneurysms is unclear. METHODS Ninety-one patients with 100 complex MCA aneurysms not amenable to simple coiling were treated with stent-assisted embolization as a first option. Technical and clinical results, initial follow-up imaging, and long-term annual MR angiography (MRA) were reviewed. RESULTS Intracranial stents were successfully deployed in all 100 aneurysms. There was 1 case of significant neurological morbidity (1%) and 1 case of death (1%) related to treatment. Initial posttreatment angiography revealed complete occlusion of 48 aneurysms (48%), a residual neck in 21 (21%), and residual aneurysm filling in 31 (31%). Follow-up imaging performed in 85 (90.4%) of a possible 94 aneurysms showed complete occlusion of 77 aneurysms (90.6%), residual neck in 3 (3.5%), and residual filling in 5 (5.9%). Four aneurysms (4.7%) required retreatment. Long-term MRA follow-up revealed stability or progressive thrombosis in 47 (97.9%) of 48 aneurysms. In 11 patients Y-configuration stenting caused only 1 minor complication and provided durable occlusion in all cases. CONCLUSIONS Stent-assisted techniques increase the number of aneurysms that may be treated endovascularly and represent an acceptable alternative to craniotomy. Stents provided adequate vessel reconstruction, low complication rates, and good long-term occlusion.

Stent assisted embolization of 64 anterior communicating artery aneurysms

Introduction Anterior communicating artery (ACoA) aneurysms comprised over half of the ruptured aneurysms in the International Subarachnoid Trial. Endovascular treatment of ACoA aneurysms has provided good results, but until the introduction of intracranial stents, many ACoA aneurysms could not be treated without craniotomy. The current study analyzes the results of ACoA aneurysm treatment using stent assisted embolization. Methods 64 patients with ACoA aneurysms underwent stent assisted aneurysm repair. Four were treated in the acute rupture phase and a fifth ruptured aneurysm was stented in a second procedure after initial coiling. Five aneurysms were 10 mm or more in greatest diameter. Follow-up angiography was performed 6 months after treatment; then, patients were followed with annual MR angiography. Technical, clinical, and long term radiographic results were analyzed. Results Stents were successfully deployed in each case. One patient was eventually treated with a three stent construct and died of perioperative hemorrhage. One major stroke occurred during a separate procedure when a patient was taken off antiplatelet medications. These cases were the only aneurysm related morbidity (1.6%) and mortality (1.6%) events during the entire follow-up period. After stent assisted embolization, 32 (50.0%) ACoA aneurysms were completely occluded, 15 (23.4%) had residual neck, and 17 (26.6%) had residual filling. At first radiographic follow-up, 39 of 55 (70.9%) showed complete occlusion. Three (5.5%) total aneurysms required retreatment. Conclusions Stent assisted aneurysm treatment was a safe and effective option in this series of ACoA aneurysms with maximum diameter less than 15 mm. ACoA aneurysms may be more likely to recur regardless of treatment option, but stent assisted embolization may be durable after stable initial radiographic follow-up.

Long-term radiographic results of stent-assisted embolization of cerebral aneurysms.

BACKGROUND Aneurysmal subarachnoid hemorrhage is a disabling disease. Endovascular coiling provides minimally invasive, effective, and safe treatment of both ruptured and unruptured intracranial aneurysms. Intracranial stents have improved the endovascular treatment of complex aneurysms, but the long-term durability of this treatment modality needs clarification. OBJECTIVE To elucidate the long-term success of intracranial stent use in the treatment of aneurysms. METHODS Four hundred ten patients were treated with stent-assisted endovascular management of 464 aneurysms. Treatment of 363 small aneurysms, 88 large aneurysms, and 13 giant aneurysms was analyzed with respect to both long-term anatomic results with digital subtraction angiography and magnetic resonance angiography over the follow-up period. RESULTS The 6-month angiographic results of 387 aneurysm treatments revealed complete aneurysm occlusion in 282 (72.9%), residual aneurysm neck in 50 (12.9%), and residual aneurysm filling in 55 (14.2%). Long-term radiographic follow-up, performed in 262 patients (mean, 3.63 years), showed significant recurrence of only 3 aneurysms after 6-month follow-up imaging. Forty-eight aneurysms (11.9%) were considered radiographic failures during the follow-up period. CONCLUSION The aneurysm recurrence rate after stent-assisted embolization in this series was similar to published data using only coil embolization for the period between treatment and the initial follow-up imaging. For aneurysms that do not initially recur, the presented data suggest improved durability in the subsequent long-term follow-up period. ABBREVIATIONS DSA, digital subtraction angiographyMRA, magnetic resonance angiography.

Complication analysis in nitinol stent-assisted embolization of 486 intracranial aneurysms.

OBJECT Stent-assisted embolization (SAE) has broadened the scope of endovascular cerebral aneurysm treatment. The risks associated with stent selection and configuration are poorly defined. In this study, the authors aimed to characterize the risk factors that contribute to complications in SAE of intracranial aneurysms. METHODS Over a 10-year period, a single surgeon treated 486 aneurysms with SAE in which open-cell Neuroform or closed-cell Enterprise stents were used. Single stents were used in 386 cases, overlapping stents were deployed in 80 cases, and Y-configuration stents were used in the remaining 20 cases. All neurological complications, which included transient deficits, were analyzed; disabling strokes and death were considered major complications. The chi-square test and multivariate logistic regression were used to evaluate the influence of aneurysm size and morphology, aneurysm location, stent selection, and stent configuration on complication rates. RESULTS There were 7 deaths (1.4%), 9 major strokes (1.9%), and 18 minor neurological complications (3.7%). For all complications, multivariate analysis revealed that large aneurysm size (10-25 mm; p = 0.01), giant aneurysm size (> 25 mm; p = 0.04), fusiform aneurysm morphology (p = 0.03), and using a Y-configuration stent (p = 0.048) were independent risk factors. For the major complications, independent risk factors included an aneurysm in the posterior circulation (p = 0.02), using an overlapping stent configuration (p = 0.03), and using a Y-configuration stent (p < 0.01). CONCLUSIONS In this series, SAE for cerebral aneurysm treatment carried an acceptable complication rate. With continued innovations in techniques and devices and with increased experience, the complication rates associated with SAE may be even lower in the future.

Use of flow-diverting stents as salvage treatment following failed stent-assisted embolization of intracranial aneurysms

Flow-diverting stents, including the Pipeline embolization device (PED) and Silk, have been beneficial in the treatment of aneurysms previously unable to be approached via endovascular techniques. Recurrent aneurysms for which stent-assisted embolization has failed are a therapeutic challenge, given the existing intraluminal construct with continued blood flow into the aneurysm. We report our experience using flow-diverting stents in the repair of 25 aneurysms for which stent-assisted embolization had failed. Nineteen (76%) of these aneurysms at the 12-month follow-up showed improved Raymond class occlusion, with 38% being completely occluded, and all aneurysms demonstrated decreased filling. One patient developed a moderate permanent neurologic deficit. Appropriate stent sizing, proximal and distal construct coverage, and preventing flow diverter deployment between the previously deployed stent struts are important considerations to ensure wall apposition and prevention of endoleak. Flow diverters are shown to be a reasonable option for treating previously stented recurrent cerebral aneurysms.

The endonasal approach for treatment of cerebral aneurysms: A critical review of the literature

The last two decades of neurosurgery have seen flourishing use of the endonasal approach for the treatment of skull base tumors. Safe and effective resections of neoplasms requiring intracranial arterial dissection have been performed using this technique. Recently, there have been a growing number of case reports describing the use of the endonasal approach to surgically clip cerebral aneurysms. We review the use of these approaches in intracranial aneurysm clipping and analyze its advantages, limitations, and consider future directions. Three major electronic databases were queried using relevant search terms. Pertinent case studies of unruptured and ruptured aneurysms were considered. Data from included studies were analyzed. 8 case studies describing 9 aneurysms (4 ruptured and 5 unruptured) treated by the endonasal approach met inclusion criteria. All studies note the ability to gain proximal and distal control and successful aneurysm obliteration was obtained for 8 of 9 aneurysms. 1 intraoperative rupture occurred and was controlled, and delayed complications of cerebrospinal fluid leak, vasospasm, and hydrocephalus occurred in 1, 1, and 2 patients, respectively. Described limitations of this technique include aneurysm orientation and location, the need for lower profile technology, and challenges with handling intraoperative rupture. The endonasal approach for clipping of intracranial aneurysms can be an effective approach in only very select cases as demonstrated clinically and through cadaveric exploration. Further investigation with lower profile clip technology and additional studies need to be performed. Options of alternative therapy, limitations of this approach, and team experience must first be considered.

Bilateral supplementary motor area syndrome causing akinetic mutism following parasagittal meningioma resection

The supplementary motor area (SMA-proper) is important for the programming and execution of motor, speech, and other elaborative functions. Unilateral SMA syndrome is well described. We present two patients who underwent resection of a large parasagittal meningioma in proximity to the SMA-proper in both hemispheres. Following surgery, these patients developed akinetic mutism; the maximal clinical deficit was not immediately evident, but manifested at 48 hours and 1 week respectively. Both patients showed complete recovery of neurological function but the process was slow. Initial return to near normal function was noted at approximately 3 months with a specific pattern; return of strength was first noted in the upper extremities followed by the lower extremities and speech and cognitive function was the last to recover. The unique occurrence of akinetic mutism secondary to bilateral SMA involvement by parasagittal meningiomas of the posterior frontal region is rare. We discuss the clinical and neuropsychological outcomes in these patients along with an analysis of the possible underlying neurophysiological mechanisms of this unique phenomenon.

Intra-Arterial Alteplase Thrombolysis during Mechanical Thrombectomy for Acute Ischemic Stroke

BACKGROUND Intra-arterial alteplase (IA tPA) is commonly used during mechanical thrombectomy for acute ischemic stroke in patients with large-vessel occlusion, but specific indications and applications for its use remain undefined. METHODS We analyzed 40 patients who underwent stent-retriever mechanical thrombectomy, 28 of whom received adjunctive IA tPA. To our knowledge, this is the largest cohort with this concomitant treatment reported in the literature in the post-mechanical thrombectomy trial era. RESULTS Between patients with and without IA tPA, rates of hemorrhagic conversion, neurologic outcome, and mortality were equivalent, with a trend toward improved angiographic revascularization observed in the IA tPA group. CONCLUSIONS IA tPA is a safe adjunct to mechanical thrombectomy, and more investigation is warranted to understand ideal indications and dosage methodologies.

Bilateral Through-and-Through Trajectory of a Low-Velocity Transcranial Penetrating Foreign Object in a Twelve-Month-Old

A 12-month-old girl sustained a penetrating intracranial trauma of a thin aluminum rod traversing from the left frontal bone and exiting the right occipital bone. The rod entered the left anterior frontal lobe, traveled through the ventricular system, narrowly missed the right posterior cerebral artery by less than 1 mm and exited through the right cerebellum. The rod was surgically extracted, and the child remained neurologically intact. Pre- and postoperative vascular imaging, antibiotics, seizure prophylaxis and surgical planning are paramount to successful care of these delicate cases.

Fusiform dilatation of the internal carotid artery following childhood craniopharyngioma resection treated by endovascular flow diversion—A case report and literature review

Fusiform dilatation of the internal carotid artery (FDICA) is a well-described radiographic finding following resection of childhood craniopharyngioma (CP). A 39-year-old woman with right-sided FDICA was successfully treated for lesion enlargement with endovascular flow diversion, which has not been described in the literature.