Richard Dalyai

Stent-Assisted Coiling of Intracranial Aneurysms Predictors of Complications, Recanalization, and Outcome in 508 Cases

Background and Purpose— Self-expanding stents are increasingly used for treatment of complex intracranial aneurysms. We assess the safety and the efficacy of intracranial stenting and determine predictors of treatment outcomes. Methods— A total of 508 patients with 552 aneurysms were treated with Neuroform and Enterprise stents between 2006 and 2011 at our institution. A multivariate analysis was conducted to identify predictors of complications, recanalization, and outcome. Results— Of 508 patients, 461 (91%) were treated electively and 47 (9%) in the setting of subarachnoid hemorrhage. Complications occurred in 6.8% of patients. In multivariate analysis, subarachnoid hemorrhage, delivery of coils before stent placement, and carotid terminus/middle cerebral artery aneurysm locations were independent predictors of procedural complications. Angiographic follow-up was available for 87% of patients at a mean of 26 months. The rates of recanalization and retreatment were, respectively, 12% and 6.4%. Older age, previously coiled aneurysms, larger aneurysms, incompletely occluded aneurysms, Neuroform stent, and aneurysm location were predictors of recanalization. Favorable outcomes were seen in 99% of elective patients and 51% of subarachnoid hemorrhage patients. Patient age, ruptured aneurysms, and procedural complications were predictors of outcome. Conclusions— Stent-assisted coiling of intracranial aneurysms is safe, effective, and provides durable aneurysm closure. Higher complication rates and worse outcomes are associated with treatment of ruptured aneurysms. Stent delivery before coil deployment reduces the risk of procedural complications. Staging the procedure may not improve procedural safety. Closed-cell stents are associated with significantly lower recanalization rates.

Stent-assisted coiling of wide-necked aneurysms in the setting of acute subarachnoid hemorrhage: experience in 65 patients.

BACKGROUND Stent-assisted coiling in the setting of subarachnoid hemorrhage remains controversial. Currently, there is a paucity of data regarding the utility of this procedure and the risks of hemorrhagic and ischemic complications. OBJECTIVE To assess the utility of stent-assisted coil embolization and pretreatment with antiplatelet agents in the management of ruptured wide-necked aneurysms. METHODS A retrospective study of 65 patients with ruptured wide-necked aneurysms treated with stent-assisted coiling. Patients with hydrocephalus or a Hunt and Hess grade ≥ III received a ventriculostomy before endovascular intervention. Patients were treated intraoperatively with 600 mg of clopidogrel and maintained on daily doses of 75 mg of clopidogrel and 81 mg of aspirin. The Glasgow outcome scale (GOS) score was recorded at the time of discharge. We identified major bleeding complications secondary to antiplatelet therapy and cases of in-stent thrombosis that required periprocedural thrombolysis. RESULTS Of the aneurysms, 66.2% arose within the anterior circulation; 69.2% of patients presented with hydrocephalus or a Hunt and Hess grade ≥ III and required a ventriculostomy. A good outcome (GOS of 4 or 5) was achieved in 63.1% of patients, and the overall mortality rate was 16.9%. There were 10 (15.38%) major complications associated with bleeding secondary to antiplatelet therapy (5 patients, 7.7%) or intraoperative in-stent thrombosis (5 patients, 7.7%). Three (4.6%) patients had a fatal hemorrhage. CONCLUSION Our findings suggest that stent-assisted coiling and routine treatment with antiplatelet agents is a viable option in the management of ruptured wide-necked aneurysms.

Subarachnoid hemorrhage with negative initial catheter angiography: a review of 254 cases evaluating patient clinical outcome and efficacy of short- and long-term repeat angiography.

BACKGROUND Subarachnoid hemorrhage (SAH) is found to have no vascular origin by initial catheter angiography in approximately 15% of cases. The most appropriate course for the type and frequency of additional diagnostic workup remains controversial. OBJECTIVE To retrospectively assess the diagnostic yield of short-term and long-term repeat catheter angiography in the era of advanced imaging. METHODS Between 2003 and 2011, 254 consecutive patients diagnosed with SAH had negative initial angiography. SAH was perimesencephalic (PM) in 46.5% and nonperimesencephalic (NPM) in 53.5%. Angiography was repeated at 1-week (short-term) and 6-week (long-term) intervals from the initial negative angiogram. RESULTS Ten of 254 patients had a vascular source of hemorrhage on short-term follow-up angiography with a diagnostic yield of 3.9%. One hundred seventy-four patients with negative findings on the first 2 angiograms received a third angiogram, and 7 of these patients were found to have a vascular abnormality. The estimated yield of this third angiogram was 4.0%. The overall diagnostic yield of repeat angiography was 0% in the PM group and 12.5% in the NPM group. The diagnostic yield of short-term and long-term follow-up angiography in patients with NPM SAH was 7.3% and 7.8%, respectively. NPM patients were more likely to experience vasospasm and hydrocephalus requiring external ventricular drainage or cerebrospinal fluid diversion than PM patients. CONCLUSION Our results support a protocol of short-term and long-term angiographic follow-up in patients with NPM SAH and negative initial angiography. Aggressive protocols of follow-up angiography may not be necessary in patients with PM SAH.

Is packing density important in stent-assisted coiling?

BACKGROUND Recent reports have shown that stent-assisted coiling (SAC) is associated with lower aneurysm recanalization rates compared with conventional coiling, raising questions about the necessity of achieving high packing density (PD) in stented aneurysms. OBJECTIVE To assess the impact of PD on follow-up obliteration rates of stented aneurysms and attempt to determine the optimal range of PD in SAC. METHODS This is a retrospective analysis of a single, large, cerebrovascular referral centers experience over a 5-year period in SAC with the use of Neuroform and Enterprise stents. The rate of complete obliteration on follow-up angiograms was compared for 3 different PD groups: high PD (>22%), moderate PD (12-22%), and low PD (<12%). RESULTS There were 292 stent-coiled aneurysms (36 ruptured, 256 unruptured) with available angiographic follow-up. Mean PD was 15.2%, and complete obliteration rate was 79.5% at latest follow-up. The rates of complete obliteration were significantly higher in the moderate (86.4%; OR = 2.58; P = .006) and high PD groups (85.3%; OR = 2.35; P = .037) compared with the low PD group (71.1%). However, no statistically significant difference was found between the moderate and high PD groups (OR = 0.91; P = .84). In multivariate analysis, PD was a significant predictor of complete obliteration (P = .007) along with smaller aneurysm volumes (P = .004). Ruptured (P = .002) and cavernous aneurysms (P < .001) had significantly lower obliteration rates. CONCLUSION High obliteration rates at follow-up were observed despite modest packing of stented aneurysms. Although PD is a definite factor in SAC, moderate and high packing of stented aneurysms seems to provide equivalent angiographic obliteration rates at follow-up.

Safety and efficacy of intraoperative angiography in craniotomies for cerebral aneurysms and arteriovenous malformations: a review of 1093 consecutive cases.

Background In an era of indocyanine angiography, the routine use of intraoperative angiography (IOA) in the surgical treatment of aneurysms and vascular malformations is controversial. Objective To retrospectively assess the safety and efficacy of IOA and to determine predictors of surgical revision. Methods Between 2003 and 2011, IOA was performed during surgical treatment of 976 aneurysms, 101 arteriovenous malformations (AVMs), and 16 arteriovenous fistulas. Results In 80 of 976 aneurysms (8.2%), IOA prompted clip repositioning. The reason for readjustment was residual aneurysm in 54.7%, parent vessel occlusion in 42.9%, and both in 2.4% of cases. In multivariate analysis, increasing aneurysm size (P, .001), ruptured aneurysm (P, .001), and increasing number of vessels injected (P, .001) were strong predictors of clip readjustment. There was a strong trend for posterior circulation aneurysm location to predict clip repositioning (P = .06). IOA revealed residual nidus/ fistula requiring further intervention in 9 of 101 AVMs (8.9%) and 3 of 16 arteriovenous fistulas (18.8%). Of 9 AVMs requiring a surgical revision, 2 (22.2%) were Spetzler-Martin grade II, 5 (55.6%) were grade III, and 2 (22.2%) were grade IV. Mean Spetzler-Martin grade was 3.0 in AVMs requiring surgical revision compared with 2.3 in those not requiring revision (P = .05). IOA-related complications were all transient or minor and occurred in 0.99% of patients; none resulted in permanent morbidity. Conclusion IOA remains a valuable tool in the surgical treatment of brain vascular abnormalities, guiding surgical re-exploration in .8% of cases. Easy access to an angiographer and routine use of IOA are important factors contributing to procedural safety and efficacy.

Long-term catheter angiography after aneurysm coil therapy: results of 209 patients and predictors of delayed recurrence and retreatment

OBJECT Aneurysm recurrence after coil therapy remains a major shortcoming in the endovascular management of cerebral aneurysms. The need for long-term imaging follow-up was recently investigated. This study assessed the diagnostic yield of long-term digital subtraction angiography (DSA) follow-up and determined predictors of delayed aneurysm recurrence and retreatment. METHODS Inclusion criteria were as follows: 1) available short-term and long-term (> 36 months) follow-up DSA images, and 2) no or only minor aneurysm recurrence (not requiring further intervention, i.e., < 20%) documented on short-term follow-up DSA images. RESULTS Of 209 patients included in the study, 88 (42%) presented with subarachnoid hemorrhage. On shortterm follow-up DSA images, 158 (75%) aneurysms showed no recurrence, and 51 (25%) showed minor recurrence (< 20%, not retreated). On long-term follow-up DSA images, 124 (59%) aneurysms showed no recurrence, and 85 (41%) aneurysms showed recurrence, of which 55 (26%) required retreatment. In multivariate analysis, the predictors of recurrence on long-term follow-up DSA images were as follows: 1) larger aneurysm size (p = 0.001), 2) male sex (p = 0.006), 3) conventional coil therapy (p = 0.05), 4) aneurysm location (p = 0.01), and 5) a minor recurrence on short-term follow-up DSA images (p = 0.007). Ruptured aneurysm status was not a predictive factor. The sensitivity of short-term follow-up DSA studies was only 40.0% for detecting delayed aneurysm recurrence and 45.5% for detecting delayed recurrence requiring further treatment. CONCLUSIONS The results of this study highlight the importance of long-term angiographic follow-up after coil therapy for ruptured and unruptured intracranial aneurysms. Predictors of delayed recurrence and retreatment include large aneurysms, recurrence on short-term follow-up DSA images (even minor), male sex, and conventional coil therapy.

Intravenous Tissue Plasminogen Activator Administration in Community Hospitals Facilitated by Telestroke Service

BACKGROUND Stroke is a leading cause of death and disability in the United States. Despite the proven benefits of intravenous tissue plasminogen activator (IV-tPA), only a small percentage of patients who have had a stroke (3.4%-5.2%) receive this US Food and Drug Administration-approved therapy. OBJECTIVE To prospectively assess the impact of a telestroke network on the rate of IV-tPA administration in patients with acute ischemic stroke in community hospitals. METHODS Thomas Jefferson University Hospital has developed a telestroke system providing acute stroke care in 28 community hospitals within the region (Pennsylvania, New Jersey, and Delaware). Telemedicine consultations are delivered through Remote Presence robotic technology. RESULTS A total of 1643 telemedicine stroke consultations were provided between January 2011 and June 2012. The mean interval from consultation request to telemedicine response was 12.0 minutes. The overall rate of IV-tPA use was 14% among all stroke consultations. A total of 237 patients (14.4%) were determined to be eligible for intravenous thrombolysis. Of those, 97% received IV-tPA. Most hospitals (82%) within the telemedicine program reported an increase in IV-tPA use (mean increase, 55%). The proportion of patients transferred to a primary stroke center after teleconsultation decreased from 44% in the first 2 quarters of 2011 to 19% in the first 2 quarters of 2012 (P < .001). CONCLUSION Implementing a telestroke system facilitates high rates of intravenous thrombolysis in patients who have had a stroke in community hospitals within a relatively short time frame. These results are higher than the national average rate (3.4%-5.2%) and support the implementation of telestroke networks for wider access to stroke expertise in underserved regions.

Stent-Assisted Endovascular Recanalization of Extracranial Internal Carotid Artery Occlusion in Acute Ischemic Stroke

OBJECTIVE Carotid artery occlusions traditionally have extremely poor outcomes with intravenous tissue plasminogen activator treatment or emergent thromboendarterectomy. We retrospectively reviewed our institutional experience with acute carotid occlusions using internal carotid artery endovascular thrombolysis and stent placement. METHODS We studied the radiographic and clinical characteristics of 17 patients with an acute cervical internal carotid artery occlusion treated with stent-assisted endovascular thrombolysis. Clinical outcomes were assessed by using National Institute of Health Stroke Scale (NIHSS) scores, which were obtained on admission and discharge. Inclusion criteria were an NIHSS score of at least 6 and the presence of significant penumbra on computed tomographic perfusion. Morbidity and mortality data were collected and analyzed. RESULTS Seventeen candidates met our inclusion criteria, 16 (94%) of whom had successful immediate recanalization of the internal carotid artery. On admission, the mean NIHSS score was 16.5 and the mean modified Rankin Scale score was 4.8. The mean NIHSS score improved to 6.9 on discharge, with a mean modified Rankin Scale score of 2.88. Eight (47%) patients recovered ambulatory function on discharge. The overall mortality rate of our series was 17%. CONCLUSIONS In the setting of acute ischemic stroke, emergent carotid artery thrombolysis and stenting is a promising treatment for acute carotid occlusions with excellent recanalization rates and favorable clinical outcomes.

Management of incidental cavernous malformations: a review

Cavernous malformations (CMs) are angiographically occult vascular malformations that are frequently found incidentally on MR imaging. Despite this benign presentation, these lesions could cause symptomatic intracranial hemorrhage, seizures, and focal neurological deficits. Cavernomas can be managed conservatively with neuroimaging studies, surgically with lesion removal, or with radiosurgery. Considering recent studies examining the CMs natural history, imaging techniques, and possible therapeutic interventions, the authors provide a concise review of the literature and discuss the optimal management of incidental CMs.

Multimodal endovascular management of acute ischemic stroke in patients over 75 years old is safe and effective

Introduction Greater attention has been directed to endovascular recanalization of acute ischemic stroke in septuagenarians and above. Technique A retrospective chart review was conducted to include patients treated for acute ischemic stroke from 2006 to 2012. All patients underwent initial neurological assessment and non-contrast head CT. Patients treated from 2009 to 2012 additionally received emergent CT angiogram and CT perfusion. 51 patients met the clinical and radiographic criteria and underwent multimodal endovascular revascularization for acute ischemic events. Results All patients underwent cerebral angiography and met angiographic criteria for endovascular thrombolysis. 34 patients (67%) were older than 80 years of age. 23 patients (45%) received intravenous tissue plasminogen activator prior to admission. Eight (16%) patients underwent stent placement after intra-arterial thrombolysis, 10 (20%) underwent balloon angioplasty and seven (14%) underwent both angioplasty and stent placement. 21 (41%) required only intra-arterial thrombolytics. An improvement in Thrombolysis in Myocardial Infarction score was noted in 34 patients (67%). The average modified Rankin Scale score on discharge was 3.9. Symptomatic intracranial hemorrhage occurred in three patients (6%); none required surgery. One patient (1.9%) had a postoperative retroperitoneal hematoma, which was managed conservatively. Two fatalities resulted from intraoperative vessel rupture (3.9%), with a combined morbidity and mortality of 27.5%. Conclusions Multimodal endovascular recanalization of acute ischemic stroke is a relatively safe treatment option in patients older than 75 years of age. Careful patient selection by clinical and radiographic inclusion criteria is necessary for the successful management of stroke in this age group.