Daniel M S Raper

Endovascular treatment of unruptured wide-necked intracranial aneurysms: comparison of dual microcatheter technique and stent-assisted coil embolization

Background Endovascular treatment of wide-necked aneurysms is challenging. Stent-assisted coiling (SAC) is associated with increased complications and requires dual antiplatelet therapy. Objective To compare treatment of unruptured, wide-necked aneurysms with a dual-microcatheter technique (DMT) versus SAC. Methods Between 2006 and 2011, 100 patients with unruptured wide-necked intracranial aneurysms were treated with DMT and 160 with SAC. Over time there was a significant decrease in the use of SAC and a corresponding increase in DMT. The investigators matched 60 patients treated with DMT blinded to outcome in a 1:2 fashion based on maximal aneurysm dome diameter with 120 patients treated with SAC. Outcomes were determined with conditional (matched) multivariate analysis. Results There were no significant differences in patient or aneurysm characteristics between cohorts, including aneurysm diameter, neck width, or volume. Overall packing density and coil volume achieved was not significantly different between cohorts. There were higher rates of overall complications in those receiving SAC (19.2%) compared with DMT (5.0%; p=0.012), but no significant difference in major complications (8.3% vs 1.7%, respectively; p=0.103). At a mean follow-up of 27.0±18.9u2005months, rates of retreatment did not differ between DMT (15.1%) and SAC (17.7%). Delayed in-stent stenosis occurred in five patients and in-stent thrombosis in four patients treated with SAC. There was no difference in favorable functional outcome (modified Rankin score 0–2) between those treated with DMT (90.6%) compared with SAC (91.2%). Conclusions DMT and SAC are effective endovascular approaches for unruptured, wide-necked aneurysms; however, DMT may result in less morbidity. Further long-term studies are necessary to determine the optimal indications for these treatment options.

Endovascular mechanical thrombectomy for cerebral venous sinus thrombosis: a systematic review

Background Cerebral venous sinus thrombosis (CVST) is an uncommon form of stroke that, when severe, can be a therapeutic challenge. Endovascular mechanical thrombectomy (EMT) techniques have significantly evolved over the past decade, but data regarding the efficacy and safety of EMT for CVST are poorly defined. Objective To summarize the large number of case series on this relatively rare condition and establish trends in the outcomes of EMT for CVST. Methods A literature review was performed using PubMed and Medline to identify reports of three or more patients with CVST treated with EMT. Baseline and outcomes data, including radiographic resolution, neurological outcome, recurrence, and treatment-related complications, were extracted for analysis. Results A total of 17 studies comprising 235 patients treated with EMT were included for analysis. Based on pooled data, 40.2% of patients presented with encephalopathy or coma. Concurrent endovascular thrombolysis was employed in 87.6% of patients. Complete radiographic resolution of CVST was achieved in 69.0% of patients. At follow-up (range 0.5–3.5u2005years), 34.7% of patients were neurologically intact and the mortality rate was 14.3%. CVST recurrence was evident in 1.2%. Worsening or new intracranial hemorrhage (ICH) occurred in 8.7% of cases. ORs of good outcome (modified Rankin Scale score 0–2) and development of ICH with sole EMT versus concurrent thrombolytic therapy were 1.51 (95% CI 0.29 to 8.15, p=0.61) and 1.15 (95% CI 0.12 to 10.80, p=0.90), respectively. Conclusions EMT is an effective salvage therapy for refractory CVST, with a reasonable safety profile. Chemical thrombolysis, in conjunction with EMT, did not appear to result in additional harm or benefit. Further analysis is warranted to determine predictors of success after EMT for CVST.

Endovascular stenting for treatment of mycotic intracranial aneurysms

Mycotic intracranial aneurysms (MIA) are a rare form of cerebrovascular pathology for which obliteration must be undertaken when they present with rupture or fail to respond to antibiotic therapy. Intracranial stents provide the unique ability to simultaneously preserve parent vessel integrity while obliterating the aneurysmal sac, but their use for the treatment of MIA has only been reported in a few instances for proximally located lesions. We report a patient with a MIA treated with endovascular stenting and review the literature for similar cases. Three case reports of four MIA treated with either stent monotherapy or stent-assisted coil embolization were identified. The clinical and radiographic features of each case were detailed. A 35-year-old with bacterial endocarditis from Streptococcus mitis was diagnosed with a ruptured 3 mm MIA of the pericallosal anterior cerebral artery after episodic diplopia. The MIA was successfully treated with stent-assisted coil embolization utilizing a Neuroform EZ stent (Stryker Neuroendovascular, Kalamazoo, MI, USA). Follow-up magnetic resonance angiography at 3months demonstrated complete aneurysm obliteration, and the patient was neurologically intact. In the literature, a M1 segment middle cerebral artery MIA, bilateral cavernous carotid MIA, and a unilateral cavernous carotid MIA were also successfully treated with Neuroform, Helistent (Hexacath, Rueil-Malmaison, France), and SILK (BALT Extrusion, Montmorency, France) stents, respectively. We present the first patient with a pericallosal MIA treated with stent-assisted coil embolization. Proper treatment of the causative organism with antibiotics minimizes the risk of infectious seeding of the stent. Intracranial stenting may be safely and effectively utilized to treat select cases of MIA.

A pilot study and novel angiographic classification for superior sagittal sinus stenting in patients with non-thrombotic intracranial venous occlusive disease

Objective Safety and efficacy of superior sagittal sinus (SSS) stenting for non-thrombotic intracranial venous occlusive disease (VOD) is unknown. The aim of this retrospective cohort study is to evaluate outcomes after SSS stenting. Methods We evaluated an institutional database to identify patients who underwent SSS stenting. Radiographic and clinical outcomes were analyzed and a novel angiographic classification of the SSS was proposed. Results We identified 19 patients; 42% developed SSS stenosis after transverse sinus stenting. Pre-stent maximum mean venous pressure (MVP) in the SSS of 16.2u2005mmu2005Hg decreased to 13.1u2005mmu2005Hg after stenting (p=0.037). Preoperative trans-stenosis pressure gradient of 4.2u2005mmu2005Hg decreased to 1.5u2005mmu2005Hg after stenting (p<0.001). No intraprocedural complication or junctional SSS stenosis distal to the stent construct was noted. Improvement in headache, tinnitus, and visual obscurations was reported by 66.7%, 63.6%, and 50% of affected patients, respectively, at mean follow-up of 5.2u2005months. We divided the SSS into four anatomically equal segments, numbered S1–S4, from the torcula to frontal pole. SSS stenosis typically occurs in the S1 segment, and the anterior extent of SSS stents was deployed at the S1–S2 junction in all but one case. Conclusions SSS stenting is reasonably safe, may improve clinical symptoms, and significantly reduces maximum MVP and trans-stenosis pressure gradients in patients with VOD with SSS stenosis. The S1 segment is most commonly stenotic, and minimum pressure gradients for symptomatic SSS stenosis may be lower than for transverse or sigmoid stenosis. Additional studies and follow-up are necessary to better elucidate appropriate clinical indications and long-term efficacy of SSS stenting.

Intracranial venous pressures under conscious sedation and general anesthesia

Introduction Venous outflow obstruction has been implicated in the pathophysiology of a subset of patients with idiopathic intracranial hypertension (IIH), and venous sinus stenting (VSS) has emerged as an effective treatment. However, the effect of anesthesia on venous sinus pressure measurements is unpredictable. A more thorough understanding of the effect of the level of anesthesia on intracranial venous pressures might help to better define patients who might benefit most from stent placement. Objective To compare, in a retrospective cohort study, intracranial venous pressures measured under conscious (CS) sedation versus general anesthesia (GA) and to assess the relationship between anesthetic-dependent venous pressures and outcomes after VSS. Methods We performed a retrospective review of a prospectively maintained database to identify patients undergoing angiographic evaluation and VSS for intracranial venous stenosis. Mean venous pressures (MVPs) and trans-stenosis pressure gradients obtained under CS were compared with those measured under GA. Results The maximal MVP was significantly lower under GA (19.8u2005mmu2005Hg) than CS (21.9u2005mmu2005Hg; p=0.029). The MVPs in the superior sagittal sinus, torcula, and transverse sinus were lower under GA, but were significantly higher in the sigmoid sinus and jugular bulb under GA (p<0.001). The mean trans-stenosis pressure gradient was also significantly lower under GA (8.6u2005mmu2005Hg) than CS (12.1u2005mmu2005Hg; p<0.001). Patients with a larger difference between maximum MVP under GA versus CS were more likely to have normalization of the MVP after VSS (p=0.0008). Conclusions Intracranial venous pressures are markedly affected by GA. In order to obtain an accurate measurement of MVPs and trans-stenosis gradients, patients undergoing investigation for IIH should undergo cerebral angiography and venous manometry under CS, which provides more reliable data for outcomes after VSS.

Stereotactic radiosurgery of meningiomas following resection: Predictors of progression

Residual or recurrent meningiomas after initial surgical resection are commonly treated with stereotactic radiosurgery (SRS), but progression of these tumors following radiosurgery is difficult to predict. We performed a retrospective review of 60 consecutive patients who underwent resection and subsequent Gamma Knife (Elekta AB, Stockholm, Sweden) radiosurgery for residual or recurrent meningiomas at our institution from 2001-2012. Patients were subdivided by Simpson resection grade and World Health Organization (WHO) grade. Cox multivariate regression and Kaplan-Meier analyses were performed to assess risk of tumor progression. There were 45 men (75%) and 15 women (25%) with a median age of 56.8 years (range 26.5-82 years). The median follow-up period was 34.9 months (range 6-108.4 months). Simpson grade 1-3 resection was achieved in 17 patients (28.3%) and grade 4 resection in 43 patients (71.7%). Thirty-four tumors (56.7%) were WHO grade 1, and 22 (36.7%) were WHO grade 2-3. Time from resection to SRS was significantly shorter in patients with Simpson grade 4 resection compared to grade 1-3 resection (p<0.01), but did not differ by WHO grade (p=0.17). Post-SRS complications occurred in five patients (8.3%). Overall, 19 patients (31.7%) experienced progression at a median of 15.3 months (range 1.2-61.4 months). Maximum tumor diameter >2.5 cm at the time of SRS (p=0.02) and increasing WHO grade (p<0.01) were predictive of progression in multivariate analysis. Simpson resection grade did not affect progression-free survival (p=0.90). The mortality rate over the study period was 8.3%. SRS offers effective tumor control for residual or recurrent meningiomas following resection, especially for small benign tumors.

Patency of the vein of Labbé after venous stenting of the transverse and sigmoid sinuses

Background Venous sinus stenting is an emerging treatment for patients with idiopathic intracranial hypertension and evidence of venous stenosis. Stents placed across the transverse and sigmoid sinuses often cover the vein of Labbé (VOL), a major anastomotic vein draining the cerebral hemisphere. The patency of the VOL after stenting and its clinical implications are poorly understood. Methods A retrospective analysis was performed of a prospectively collected database of patients undergoing venous sinus stenting. Pre- and post-stent angiography were compared to assess changes in VOL patency, clinical and radiographic outcomes. Results The study cohort comprised 56 patients. The stent covered the VOL in 92.9% of cases. Thirty-two cases with VOL coverage had evaluable angiograms immediately after stent placement. Among these, VOL filled normally in 75.0%, exhibited diminished caliber with normal transit time in 3.1%, filled sluggishly in 18.8%, and was occluded in 3.1%. Follow-up was assessed in patients with at least 3u2005months angiographic follow-up (46 patients, mean 7.2u2005months). Of these, normal filling was seen in 71.7%, diminished caliber in 26.1%, and sluggish filling in 2.2% of cases. Neither stent coverage of the VOL nor its patency immediately after stenting or at follow-up correlated with stent-adjacent stenosis. There were no neurological sequelae from coverage of the VOL or alteration of its drainage pattern. Conclusions In the majority of venous stenting cases involving the transverse and sigmoid sinuses, the VOL remains widely patent. Complete VOL occlusion rarely occurs after stenting and may not result in clinical sequelae. Stent coverage of the VOL should not deter the therapeutic use of venous sinus stenting.

Endovascular Mechanical Thrombectomy for Acute Middle Cerebral Artery M2 Segment Occlusion: A Systematic Review

INTRODUCTIONnThe benefit of endovascular mechanical thrombectomy (EMT) for acute distal occlusions of the middle cerebral artery M2 segment is incompletely defined. The aim of this systematic review is to analyze the recent literature regarding EMT for acute M2 occlusions.nnnMETHODSnWe reviewed the literature to identify all studies of patients with acute M2 occlusions who underwent EMT that were published after January 1, 2015. Excellent and good outcomes were defined as modified Rankin Scale score of 0-1 and 0-2, respectively, at 3 months. Successful reperfusion was defined as modified Thrombolysis In Cerebral Infarction (mTICI) score of 2b-3.nnnRESULTSnEight studies, comprising 630 EMT-treated patients with acute M2 occlusions, were included in the analysis. The median National Institute of Health Stroke Scale score ranged from 10 to 16, and the median Alberta Stroke Program Computed Tomography Score ranged from 9 to 10. Excellent and good outcomes at 3-month follow-up were observed in 40% and 62%, respectively, of patients with acute M2 occlusion who underwent EMT, with a mortality of 11%. Successful reperfusion was achieved in 78% of cases. Postprocedural intracerebral hemorrhage (ICH) occurred in 14% of patients, including a symptomatic ICH rate of 5%.nnnCONCLUSIONSnEMT for acute M2 occlusion affords functional independence to most patients, with a modest rate of symptomatic ICH. However, compared with the natural history of distal MCA occlusions, the benefit of M2 thrombectomy using stent retriever or direct aspiration techniques remains unclear.

Endovascular treatment for cerebral vasospasm following aneurysmal subarachnoid hemorrhage: predictors of outcome and retreatment

Objective Although endovascular therapy has been widely adopted for the treatment of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (aSAH), its effect on clinical outcomes remains incompletely understood. The aims of this retrospective cohort study are to evaluate the outcomes of endovascular intervention for post-aSAH vasospasm and identify predictors of functional independence at discharge and repeat endovascular vasospasm treatment. Methods We assessed the baseline and outcomes data for patients with aSAH who underwent endovascular vasospasm treatment at our institution, including intra-arterial (IA) vasodilator infusion and angioplasty. Statistical analyses were performed to determine factors associated with good outcome at discharge (modified Rankin Scale 0–2) and repeat endovascular vasospasm treatment. Results The study cohort comprised 159 patients with a mean age of 52 years. Good outcome was achieved in 17% of patients at discharge (26/150 patients), with an in-hospital mortality rate of 22% (33/150 patients). In the multivariate analysis, age (OR 0.895; p=0.009) and positive smoking status (OR 0.206; p=0.040) were negative independent predictors of good outcome. Endovascular retreatment was performed in 34% (53/156 patients). In the multivariate analysis, older age (OR 0.950; p=0.004), symptomatic vasospasm (OR 0.441; p=0.046), initial treatment with angioplasty alone (OR 0.096; p=0.039), and initial treatment with combined IA vasodilator infusion and angioplasty (OR 0.342; p=0.026) were negative independent predictors of retreatment. Conclusion We found a modest rate of functional independence at discharge in patients with aSAH who underwent endovascular vasospasm treatment. Older patients and smokers had worse functional outcomes at discharge. Initial use of angioplasty appears to decrease the need for subsequent retreatment.

Posterior circulation perforator aneurysms: a proposed management algorithm

Introduction Subarachnoid hemorrhage (SAH) from posterior circulation perforator aneurysms (PCPAs) is rare and its natural history is unknown. Diagnosis may be difficult, acute management is poorly defined, and long-term recurrent SAH rates and clinical outcome data are lacking. Methods We searched our institutions records for cases of PCPA rupture and analyzed patient demographics, Hunt and Hess (HH) grades, diagnostic imaging, management, and clinical outcomes. We conducted telephone interviews to calculate modified Rankin Scale (mRS) scores. Results We identified 9 patients (6 male, 3 female) with a ruptured PCPA who presented to the University of Virginia Health System (Charlottesville, VA, USA) between 2010 and 2016. Median and mean ages were 62 and 63u2005years, respectively. Median HH grade was 3. Seven of nine (78%) PCPAs were angiographically occult on initial imaging and median time to diagnosis was 5u2005days. Three conservatively managed patients had a mean mRS score of 0.67 (range 0–1) at mean follow-up of 35.3u2005months. Antifibrinolytic therapy was administered to all conservatively managed patients without thrombotic complication. Six patients receiving endovascular treatment had a mean mRS score of 2.67 (range 0–6) at mean follow-up of 49.2u2005months. No cases of recurrent SAH were seen in the study. Conclusions The rarity of PCPA has precluded long-term clinical follow-up until now. Our experience suggests low recurrent SAH rates. Until further studies are performed, conservative management, possibly combined with antifibrinolytic therapy, may be a viable treatment with acceptable long-term outcome.