Mocco, J

Abstract BACKGROUND There is a paucity of literature regarding treatment options for extracranial pseudoaneurysms of the internal carotid artery (ICA). To date, Pipeline Embolization Device (PED; Medtronic Inc) use for the treatment of extracranial pseudoaneurysms of the ICA has only been reported from single-center case series. OBJECTIVE To evaluate the safety and efficacy of PED for the treatment of extracranial ICA pseudoaneurysms. METHODS This is a multicenter retrospective study involving 6 high-volume tertiary academic institutions in the United States. We analyzed patients with extracranial ICA pseudoaneurysms treated with PED between January 1, 2011, and January 1, 2019. Clinical assessment was performed pre- and postintervention using the modified Rankin Scale (mRS) and National Institution of Health Stroke Scale (NIHSS) at a minimum of 4-mo follow-up. RESULTS A total of 28 pseudoaneurysms with a mean diameter of 17.7 mm (range: 4.1-52.5 mm) were treated with PED in 24 patients at 6 participating centers. The mean age was 52.1 yr (17-73) ± 14.3 with 14 females and 10 males. At a mean of 21-mo (range 4-66 mo) follow-up, complete occlusion was achieved in 89% (n = 25/28), with near-complete occlusion (>90% occlusion) in the remainder. There were no periprocedural complications. Postprocedure NIHSS was 0 in 88% (n = 21/24) and 1 in 12% (n = 3/24) of patients, and mRS was 0 in 83% (n = 20/24) and 1 in 17% (n = 4/24) of patients. CONCLUSION The treatment of extracranial ICA pseudoaneurysms with PED is safe and effective in selected patients. Randomized controlled trials and prospective cohort studies are needed to establish the role of flow diversion for ICA pseudoaneurysms.

Abstract BACKGROUND Neck remnants are not uncommon after endovascular treatment of cerebral aneurysms. Critics of endovascular treatments for cerebral aneurysms cite neck remnants as evidence in favor of microsurgical clipping. However, studies have failed to evaluate the true clinical significance of aneurysm neck remnants following endovascular therapies. OBJECTIVE To assess the clinical significance of residual aneurysm necks and to determine the rate of subsequent rupture following coiling or stent-assisted coiling of cerebral aneurysms. METHODS We retrospectively reviewed the records of 1292 aneurysm cases that underwent endovascular treatment at 4 institutions. Aneurysms treated by primary coiling or stent-assisted coiling were included in the study; those treated by flow diversion were excluded Aneurysms with residual filling (i.e., Raymond–Roy Occlusion Classification II, neck remnant; or III, residual aneurysm filling) were assessed for their risk of subsequent rupture. RESULTS A total of 626 aneurysms were identified as having residual filling immediately posttreatment. Of these, 13 aneurysms (2.1%) ruptured during the follow-up period (mean 7.3 mo; range 1-84 mo). Eleven of the 13 (84.6%) were ruptured at presentation. Rupture at presentation, the size of the aneurysm, and the increasing age of the patient were predictive of posttreatment rupture. CONCLUSION We found that unruptured aneurysms with residual necks following endovascular treatment posed a very low risk of rupture (0.6%). However, patients presenting with ruptured aneurysms had a higher risk of rerupture from a neck remnant (3.4%). These results highlight the importance of achieving complete angiographic occlusion of ruptured aneurysms.

Background The angiographic evaluation of previously coiled aneurysms can be difficult yet remains critical for determining re-treatment. Objective The main objective of this study was to determine the inter-rater reliability for both the Raymond Scale and per cent embolization among a group of neurointerventionalists evaluating previously embolized aneurysms. Methods A panel of 15 neurointerventionalists examined 92 distinct cases of immediate post-coil embolization and 1 year post-embolization angiographs. Each case was presented four times throughout the study, along with alterations in demographics in order to evaluate intra-rater reliability. All respondents were asked to provide the per cent embolization (0–100%) and Raymond Scale grade (1-3) for each aneurysm. Inter-rater reliability was evaluated by computing weighted kappa values (for the Raymond Scale) and intraclass correlation coefficients (ICC) for per cent embolization. Results 10 neurosurgeons and 5 interventional neuroradiologists evaluated 368 simulated cases. The agreement among all readers employing the Raymond Scale was fair (κ=0.35) while concordance in per cent embolization was good (ICC=0.64). Clinicians with fewer than 10 years of experience demonstrated a significantly greater level of agreement than the group with greater than 10 years (κ=0.39 and ICC=0.70 vs κ=0.28 and ICC=0.58). When the same aneurysm was presented multiple times, clinicians demonstrated excellent consistency when assessing per cent embolization (ICC=0.82), but moderate agreement when employing the Raymond classification (κ=0.58). Conclusions Identifying the per cent embolization in previously coiled aneurysms resulted in good inter- and intra-rater agreement, regardless of years of experience. The strong agreement among providers employing per cent embolization may make it a valuable tool for embolization assessment in this patient population.

Abstract BACKGROUND There are conflicting data between natural history studies suggesting a very low risk of rupture for small, unruptured intracranial aneurysms and retrospective studies that have identified a much higher frequency of small, ruptured aneurysms than expected. OBJECTIVE To use the prospective International Study of Unruptured Intracranial Aneurysms cohort to identify morphological characteristics predictive of unruptured intracranial aneurysm rupture. METHODS A case-control design was used to analyze morphological characteristics associated with aneurysm rupture in the International Study of Unruptured Intracranial Aneurysms database. Fifty-seven patients with ruptured aneurysms during follow-up were matched (by size and location) with 198 patients with unruptured intracranial aneurysms without rupture during follow-up. Twelve morphological metrics were measured from cerebral angiograms in a blinded fashion. RESULTS Perpendicular height ( P = .008) and size ratio (ratio of maximum diameter to the parent vessel diameter; P = .01) were predictors of aneurysm rupture on univariate analysis. Aspect ratio, daughter sacs, multiple lobes, aneurysm angle, neck diameter, parent vessel diameter, and calculated aneurysm volume were not statistically significant predictors of rupture. On multivariate analysis, perpendicular height was the only significant predictor of rupture (Chi-square 7.1, P -value .008). CONCLUSION This study underscores the importance of other morphological factors, such as perpendicular height and size ratio, that may influence unruptured intracranial aneurysm rupture risk in addition to greatest diameter and anterior vs posterior location.

OBJECT The authors sought to determine whether flow diversion with the Pipeline Embolization Device (PED) can approximate microsurgical decompression in restoring function after cranial neuropathy following carotid artery aneurysms. METHODS This multiinstitutional retrospective study involved 45 patients treated with PED across the United States. All patients included presented between November 2009 and October 2013 with cranial neuropathy (cranial nerves [CNs] II, III, IV, and VI) due to intracranial aneurysm. Outcome analysis included clinical and procedural variables at the time of treatment as well as at the latest clinical and radiographic follow-up. RESULTS Twenty-six aneurysms (57.8%) were located in the cavernous segment, while 6 (13.3%) were in the clinoid segment, and 13 (28.9%) were in the ophthalmic segment of the internal carotid artery. The average aneurysm size was 18.6 mm (range 4–35 mm), and the average number of flow diverters placed per patient was 1.2. Thirty-eight patients had available information regarding duration of cranial neuropathy prior to treatment. Eleven patients (28.9%) were treated within 1 month of symptom onset, while 27 (71.1%) were treated after 1 month of symptoms. The overall rate of cranial neuropathy improvement for all patients was 66.7%. The CN deficits resolved in 19 patients (42.2%), improved in 11 (24.4%), were unchanged in 14 (31.1%), and worsened in 1 (2.2%). Overtime, the rate of cranial neuropathy improvement was 33.3% (15/45), 68.8% (22/32), and 81.0% (17/21) at less than 6, 6, and 12 months, respectively. At last follow-up, 60% of patients in the isolated CN II group had improvement, while in the CN III, IV, or VI group, 85.7% had improved. Moreover, 100% (11/11) of patients experienced improvement if they were treated within 1 month of symptom onset, whereas 44.4% (12/27) experienced improvement if they treated after 1 month of symptom onset; 70.4% (19/27) of those with partial deficits improved compared with 30% (3/10) of those with complete deficits. CONCLUSIONS Cranial neuropathy caused by cerebral aneurysm responds similarly when the aneurysm is treated with the PED compared with open surgery and coil embolization. Lower morbidity and higher occlusion rates obtained with the PED may suggest it as treatment of choice for some of these lesions. Time to treatment is an important consideration regardless of treatment modality.

There is no standard of care for catheter size or post-procedure supine time in cerebral angiography. Catheter sizes range from 4-Fr to 6-Fr with supine times ranging from two to over six hours. The objective of our study was to establish the efficacy, safety, and cost savings of two-hour supine time after 4-Fr elective cerebral angiography. A prospective, single arm study was performed on 107 patients undergoing elective cerebral angiography. All cerebral angiograms were performed with a 4-Fr sheath-based system without closure devices. Ten minutes of manual compression was applied to the femoral access site, with further compression held as clinically indicated. Patients were then monitored in a nursing unit for two hours supine and subsequently mobilized. Nursing discretion was allowed for earlier mobilization. Patients were called the next day to assess delayed hematoma and bleeding. Estimates of cost savings and productivity increases are provided. All patients ambulated in two hours or less. There were no strokes or vessel dissections. Five patients (4.7%) experienced a palpable hematoma, three patients (2.8%) experienced bleeding immediately following the procedure requiring further compression, and one patient (0.9%) experienced minor groin oozing at home. No patient required transfusion, thrombin injection, or endovascular/surgical management of a groin complication. A two-hour post-procedure supine time resulted in cost savings of $952 per angiogram and a total of $101,864. 4-Fr sheath based cerebral angiography with two-hour post-procedure supine time is safe and effective, and allows for a considerable increase in patient satisfaction, cost savings and productivity.

Background and Purpose— To address the increasing need to counsel patients about treatment indications for unruptured intracranial aneurysms (UIA), we endeavored to develop a consensus on assessment of UIAs among a group of specialists from diverse fields involved in research and treatment of UIAs. Methods— After composition of the research group, a Delphi consensus was initiated to identify and rate all features, which may be relevant to assess UIAs and their treatment by using ranking scales and analysis of inter-rater agreement (IRA) for each factor. IRA was categorized as very high, high, moderate, or low. Results— Ultimately, 39 specialists from 4 specialties agreed (high or very high IRAs) on the following key factors for or against UIA treatment decisions: (1) patient age, life expectancy, and comorbid diseases; (2) previous subarachnoid hemorrhage from a different aneurysm, family history for UIA or subarachnoid hemorrhage, nicotine use; (3) UIA size, location, and lobulation; (4) UIA growth or de novo formation on serial imaging; (5) clinical symptoms (cranial nerve deficit, mass effect, and thromboembolic events from UIAs); and (6) risk factors for UIA treatment (patient age and life expectancy, UIA size, and estimated risk of treatment). However, IRAs for features rated with low relevance were also generally low, which underlined the existing controversy about the natural history of UIAs. Conclusions— Our results highlight that neurovascular specialists currently consider many features as important when evaluating UIAs but also highlight that the appreciation of natural history of UIAs remains uncertain, even within a group of highly informed individuals.

Various endovascular intraarterial approaches are available for treating patients with acute ischemic stroke who present with severe neurological deficits. Three recent randomized trials—Interventional Management of Stroke (IMS) III, Mechanical Retrieval and Recanalization of Stroke Clots Using Embolectomy (MR RESCUE), and Synthesis Expansion: A Randomized Controlled Trial on Intra-Arterial Versus Intravenous Thrombolysis in Acute Ischemic Stroke (SYNTHESIS Expansion)—evaluated the efficacy of endovascular treatment of acute ischemic stroke and, after failing to demonstrate any significant clinical benefit of endovascular therapies, raised concerns and questions in the medical community regarding the future of endovascular treatment for acute ischemic stroke. In this paper, the authors review the evolution of endovascular treatment strategies for the treatment of acute stroke and provide their interpretation of findings and potential limitations of the three recently published randomized trials. The authors discuss the advantage of stent-retriever technology over earlier endovascular approaches and review the current status and future directions of endovascular acute stroke studies based on lessons learned from previous trials.

Introduction The successful treatment of intracranial aneurysms is dependent on a full understanding of the anatomic relationship of a given aneurysm to its parent artery(s) and nearby branches. Furthermore, new endovascular technologies are often limited by size constraints. Currently, there is no complete atlas describing diameters for each major intracranial arterial segment. We sought to obtain these data by performing a systematic analysis of selected cerebral angiography images from the International Study of Unruptured Intracranial Aneurysms (ISUIA). Methods Four hundred and forty-five patients with unruptured intracranial aneurysms from the ISUIA database were reviewed. Using previously described techniques, artery diameters were measured for all arteries involved in the aneurysm neck for each patient. Results Measurements were obtained from 695 different aneurysm-associated arterial segments among 445 patient angiograms (mean 1.6 measurements per aneurysm). Artery diameters, mean, median, SEM and IQRs based upon the different arterial segments are presented. Conclusions This angiographic almanac of aneurysm-associated intracranial arterial diameters may be of benefit in establishing standard norms through which devices, protocols and research aims may be developed.