Christopher J. Koebbe

Endovascular coil embolization of ruptured and unruptured posterior circulation aneurysms: Review of a 10-year experience - Commentary

OBJECTIVETreatment of posterior circulation aneurysms poses a great technical challenge for the practicing neurosurgeon. The advent of endovascular techniques has made such treatment more feasible. We report our experience with the endovascular management of ruptured and unruptured posterior circulation aneurysms during the past 10 years. METHODSA retrospective analysis was performed on all patients with posterior circulation aneurysms undergoing endovascular treatment at Jefferson Hospital for Neuroscience between July 1995 and December 2005. This yielded 275 patients (67 men and 208 women). The degree of aneurysm occlusion was determined by the operating endovascular neurosurgeon at the time of the procedure. Successful embolization was defined as greater than 95% occlusion of the dome without any coil prolapsing into the parent vessel. Clinical outcome was evaluated using the modified Glasgow Outcome Scale. Clinical follow-up data was obtained for 262 patients (95.3%); the follow-up period ranged from 1 to 94 months (mean, 31.8 mo for procedures performed before 2004 and 13.3 mo for procedures performed during 2004 and 2005). Angiographic follow-up data was obtained for 224 patients (84.8%) for periods ranging from 6 to 94 months (mean, 31.3 mo for procedures performed before 2004 and 13.7 mo for procedures performed during 2004 and 2005). RESULTSBased on the Hunt and Hess grading scale, the patient population included 106 patients (38.5%) with unruptured aneurysms, 43 patients (15.6%) with Grade I aneurysms, 16 patients (5.8%) with Grade II aneurysms, 56 patients (20.5%) with Grade III aneurysms, and 54 patients (19.6%) with Grade IV aneurysms. The locations of the posterior circulation aneurysms included 189 (68.7%) in the basilar apex or posterior cerebral artery, 23 (8.4%) in the basilar trunk/anterior inferior cerebellar artery, 22 (8%) in the superior cerebellar artery, and 41 (14.9%) in the vertebral artery or posterior inferior cerebellar artery. Of the 275 patients, 208 (76%) were women and 67 (24%) were men. The mean age at the time of treatment was 53.9 years (range, 7–90 yr). Of all patients treated, 237 patients (87.8%) had successful embolization (>95% occlusion of the dome). On angiographic follow-up, 55 patients (24.5%) developed recanalization of at least 5%. Retreatment was required in 11 patients (4.9%; 0.01%/patient yr) and rehemorrhage occurred in three patients (1.1%; 0.003%/patient yr). Clinical follow-up was graded using the modified Glasgow Outcome Scale (mGOS) and revealed 229 patients (87.4%) in the mGOS I category, 12 patients (4.6%) in the mGOS II category, eight patients (3%) in the mGOS III category, two patients (0.8%) in the mGOS IV category, and 11 patients (4.2%) were deceased (mGOS V). Clinically significant vasospasm requiring angioplasty occurred in 11 patients (6.5%) with subarachnoid hemorrhage, and 120 patients (71%) with subarachnoid hemorrhage required ventricular shunts. Complications causing clinical morbidity occurred in 14 patients (5.1%) and ranged from postoperative ischemia to recurrent subarachnoid hemorrhage. Of all clinical factors evaluated, Hunt and Hess grade was the strongest predictor of good clinical outcome (P < 0.0001). CONCLUSIONEndovascular coil embolization of posterior circulation aneurysms is an effective treatment in the short term but is associated with recurrence, which requires close surveillance, possible retreatment, and can, albeit very rarely, lead to rehemorrhage. Future technological advancements such as the development of biologically active coils will be essential in the permanent obliteration of aneurysms.

Endovascular management of intracranial aneurysms: current experience and future advances.

OBJECTIVE:The past 15 years have seen a revolution in the treatment of intracranial aneurysms. Endovascular technology has evolved rapidly since the Food and Drug Administration approval of Guglielmi detachable coils in 1995, which now allows successful treatment of most aneurysms. The authors provide a review of their 11-year experience at Jefferson Hospital for Neuroscience with endovascular embolization of intracranial aneurysms and discuss clinical trial outcomes and future directions of this treatment method. METHODS:The authors reviewed the clinical and angiographic outcomes for 1307 patients undergoing endovascular treatment of intracranial aneurysms. Their analysis focuses on posterior circulation and middle cerebral artery aneurysms, as well as cases of stent-assisted coil embolization. They review their procedural protocol and patient selection criteria for endovascular management. RESULTS:Several large clinical trials have demonstrated the safety and efficacy of endovascular treatment of intracranial aneurysms. The International Subarachnoid Aneurysm Trial provides Level I evidence demonstrating a significant reduction in disability or death with endovascular treatment compared with surgical clipping. The most common procedural complications include intraprocedural rupture and thromboembolic events; avoidance strategies are also discussed. Vasospasm after subarachnoid hemorrhage causes neurological morbidity and mortality and can be successfully managed by early recognition and interventional treatment with angioplasty, pharmacologic agents, or both. CONCLUSION:Long-term studies evaluating experience with aneurysm coil embolization during the past decade indicate that this is a safe and durable treatment method. The introduction of stent-assist techniques has improved the management of wide-neck aneurysms. Future technology developments will likely improve the durability of endovascular treatment further by delivering bioactive agents that promote aneurysm thrombosis beyond the coil mass alone. It is clear that endovascular therapy of both ruptured and unruptured aneurysms is becoming a mainstay of practice in this patient population. Although not replacing open surgery, the continued improvements have allowed aneurysms that previously were amenable only to open clip ligation to be treated safely with durable long-term outcomes.

INITIAL EXPERIENCE WITH BIOACTIVE CERECYTE DETACHABLE COILS: IMPACT ON REDUCING RECURRENCE RATES

OBJECTIVEDespite proven safety of endovascular coil embolization of intracranial aneurysms, the potential need for retreatment remains criticized. The goal of this prospective study was to assess the safety, durability, and effect on recanalization rates of the Cerecyte (Micrus Corp., Sunnyvale, CA) bioactive coil. METHODSTwo hundred twelve ruptured and unruptured aneurysms in 176 patients were prospectively enrolled in a database registry during a 12-month period. Adverse clinical outcomes directly attributed to the use of the Cerecyte coil were documented. Angiographic outcomes were determined immediately after coil embolization and during follow-up studies. All patients who received stent assistance or a non-Cerecyte coil were excluded. Two independent endovascular surgeons reviewed follow-up films. Any discrepancy was deemed a recurrence. RESULTSAfter exclusion criteria, 81 patients with 89 aneurysms were available for a minimum of 6 months of follow-up. Of those 89 aneurysms, 65% were ruptured aneurysms and were treated in the acute setting. The mean size of the aneurysm was 7 mm. The mean angiographic follow-up period was 11.2 months. Recurrences requiring retreatment as a result of dome filling were identified in six aneurysms (6.7%). Four aneurysms (4%) developed compaction of more than 20%, which was defined as interstitial filling of the fundus. There was one thromboembolic event leading to permanent neurological deficit. No cases of chemical meningitis or delayed hydrocephalus occurred. CONCLUSIONThe Cerecyte bioactive coil seems to be safe and effective for use in both ruptured and unruptured aneurysms. The bioactive polymer within the coils allows similar handling characteristics of a bare platinum coil. Studies to assess long-term outcomes with direct comparison to platinum coils and alternative bioactive coils are warranted.

LOW INCIDENCE OF SYMPTOMATIC STROKES AFTER CAROTID STENTING WITHOUT EMBOLIZATION PROTECTION DEVICES FOR EXTRACRANIAL CAROTID STENOSIS : A SINGLE-INSTITUTION RETROSPECTIVE REVIEW. Commentary

OBJECTIVECarotid angioplasty and stenting (CAS) remains the primary modality of treating individuals with carotid stenosis and significant comorbidities or anatomically difficult lesions. The use of embolization protection devices (EPD) has been mandated by the cerebrovascular community even though the ability of these devices to prevent symptomatic strokes is not supported by the current literature. Our goal was to assess the clinical and radiological outcomes of patients who underwent CAS without EPDs at our hospital from 1996 to 2006. METHODSWe performed a retrospective chart analysis of all patients who underwent CAS without EPDs at the Jefferson Hospital for Neuroscience in Philadelphia, PA. The clinical and angiographic outcomes of these patients were studied retrospectively using chart reviews and operative, angiographic, and radiological reports. The mean clinical and radiological follow-up period was 18.6 months. RESULTSOne hundred five patients (97.2%) had clinical follow-up at 1 month. During this period, the following complications were observed: cerebrovascular accidents in 2 patients (1.9%), myocardial infarctions in 2 patients (1.9%), femoral hematoma in 1 patient (0.9%), retroperitoneal hematomas in 3 patients (2.8%), and cervical carotid dissections in 4 patients (3.7%); 2 patients (1.9%) died. Seventy-six patients (80.9%) had a mean clinical follow-up period of 18.6 months. During this period, 2 patients (2.6%) had cerebrovascular accidents, 1 of which was fatal. The long-term morbidity and mortality rate was 2.6%. In the same follow-up period, the restenosis (>50% stenosis from baseline) rate was 9.2% (7 patients). Three (3.9%) of these patients went on to require repeat CAS. CONCLUSIONOur experience reveals that CAS can be performed safely with risks similar to those reported in series in which EPDs were used. Any procedure or device that adds risk and cost to the patient should be evaluated with a randomized, controlled trial to evaluate its efficacy, especially in situations in which published data provide conflicting results. The use of EPDs should be no exception to this paradigm.

The role of carotid angioplasty and stenting in carotid revascularization.

Abstract Objectives: The gold standard procedure for carotid revascularization has been carotid endarterectomy. Several randomized trials demonstrate that it is more efficacious than medical management in stroke prevention for both symptomatic and asymptomatic patients when performed with low surgical morbidity. However, many high-risk patients not included in these trials are now being referred for carotid revascularization. Endovascular treatment of carotid stenosis with angioplasty and stenting has become an established alternative to carotid endarterectomy (CEA) for these patients. We provide a review of the current role of carotid stent and angioplasty. Methods: We reviewed our procedural techniques for carotid artery stenting (CAS) with an emphasis on the need for medical therapy before and after the procedure to reduce thromboembolic complications. We also retrospectively analysed our clinical outcomes and incidence of restenosis after CAS. Results: We evaluated 139 of 252 patients treated over a 10-year period who had a minimum of 6-month clinical and imaging (ultrasound and/or angiography) follow-up (average f/u=60 months). Our rate of major stroke, MI or death was 3%, and rate of peri-operative TIAs was 2%. Morbidity related to femoral sheath placement has been 1.5%, with one cold foot resolved with heparin and one retroperitoneal hematoma requiring transfusion. Recurrent stenosis after CAS occurred in 4% of patients, predominately following radiation treatment where it was 15%. Discussion: Although CEA is the gold standard procedure to prevent stroke from carotid stenosis, CAS has an expanding role for revascualrization, particularly in high-risk patients. Several randomized prospective trials are ongoing to better define the indications for CAS versus CEA.