Subtemporal Approach for the Treatment of Ruptured and Unruptured Distal Basilar Artery Aneurysms: Is There a Contemporary Use?

Operative Neurosurgery 27:581–596, 2024

Distal basilar artery aneurysms (DBAs) are high-risk lesions for which endovascular treatment is preferred because of their deep location, yet indications for open clipping nonetheless remain. The subtemporal approach allows for early proximal control and direct visualization of critical posterior perforating arteries, especially for posterior-projecting aneurysms. Our objective was to describe our clinical experience with the subtemporal approach for clipping DBAs in the evolving endovascular era.

METHODS: This was a retrospective, single-institution case series of patients with DBAs treated with microsurgery over a 21-year period (2002-2023). Demographic, clinical, and surgical data were collected for analysis.

RESULTS: Twenty-seven patients underwent clipping of 11 ruptured and 16 unruptured DBAs with a subtemporal approach (24 female; mean age 53 years). Ten patients had expanded craniotomies for treatment of additional aneurysms. The aneurysm occlusion rate was 100%. Good neurological outcomes as defined by the modified Rankin Scale score ≤2 and Glasgow Outcome Scale score ≥4 were achieved in 21/27 patients (78%). Two patients died before hospital discharge, one from vasospasm-induced strokes and another from an intraoperative myocardial infarction.

CONCLUSION: These results demonstrate that microsurgical clip ligation of DBAs using the subtemporal approach remains a viable option for complex lesions not amenable to endovascular management.

The impact of regular aspirin use on aneurysm recanalization rates after endovascular coiling

J Neurosurg 141:1020–1025, 2024

Intracranial aneurysms (IAs) pose a significant health risk, often leading to subarachnoid hemorrhage and severe neurological outcomes. Endovascular coiling has been a principal treatment method, but it comes with the challenge of high recanalization rates. Aspirin has recently emerged as a potential agent to reduce these rates. In this study, the authors aimed to investigate the impact of regular aspirin use on aneurysm recanalization rates following endovascular coiling in a 10-year single-institution study.

METHODS A retrospective analysis was conducted on a dataset of 2236 aneurysms treated by a single neurosurgeon over a period of 10 years. The primary outcome measure was aneurysm recanalization, defined by a change in the Raymond-Roy Occlusion Classification of at least one grade.

RESULTS A total of 525 aneurysms were coiled, 109 of which involved patients who reported regular use of aspirin. The recanalization rate was significantly lower in the aspirin group (9.2%) compared with the control group (23.6%) (OR 0.33, 95% CI 0.15–0.66; p = 0.001). On analysis of the specific mechanisms of recanalization, aneurysm sac growth was less frequent in the aspirin group (5.5%) compared with the control group (18%) (OR 0.265, 95% CI 0.09–0.63; p = 0.002). Additionally, patients in the control group had a higher retreatment rate (18%) than patients in the aspirin group (5.5%) (OR 0.265, 95% CI 0.09–0.63; p = 0.002).

CONCLUSIONS Regular use of aspirin appears to be associated with reduced rates of aneurysm recanalization after endovascular coiling. However, caution is advised in interpretation of these results given the retrospective nature of this study. Further randomized controlled trials are needed to confirm these findings.

Incidence and Characteristics of Cerebral Infarction After Microsurgical Clipping of Unruptured Anterior Circulation Cerebral Aneurysms

Neurosurgery 95:798–806, 2024

Postclipping cerebral infarction (PCI) remains a major concern after treatment for unruptured intracranial aneurysms (UIAs). However, studies of microsurgical clipping based on diffusion-weighted imaging are limited. We aimed to present the incidence, risk factors, and types of PCI and its radiological and clinical characteristics.

METHODS: This was a retrospective single-center study in which patients were scheduled to undergo microsurgical clipping for anterior circulation UIAs. The overall incidence and risk factors were calculated. Based on the operation and relevant artery, we categorized PCI on diffusion-weighted imaging into 4 types and presented their radiological and clinical characteristics.

RESULTS: We reviewed the radiological and clinical data of 605 patients. The overall incidence of PCI was 16.7% (101/ 605), of which asymptomatic infarction was 14.9% (90/605) and symptomatic infarction was 1.8% (11/605). Hypertension (adjusted odds ratio [aOR], 2.258; 95% confidence interval [CI]: 1.330-3.833), temporary clipping (aOR, 1.690; 95% CI: 1.034-2.760), multiple aneurysm locations (aOR, 1.832; 95% CI: 1.084-3.095), and aneurysm dome size (aOR, 1.094; 95% CI: 1.006-1.190) were independent risk factors for PCI. Type II (perianeurysmal perforator) infarction was the most common type of PCI (48.6%) and the most common cause of symptomatic infarction (72.7%). Types II and III (distal embolic) infarctions correlated with atherosclerotic changes in the aneurysm wall and temporary clipping (62.4% and 70.6%, respectively). The type IV (unrelated) infarction group had a higher incidence of systemic atherosclerosis (55%).

CONCLUSION: Microsurgical clipping is a safe and viable option for the treatment of anterior circulation UIAs. However, modification of the surgical technique, preoperative radiological assessment, and patient selection are required to reduce the incidence of PCI.

Stent-assisted Woven EndoBridge device for the treatment of intracranial aneurysms: an international multicenter study

J Neurosurg 140:1071–1079, 2024

The Woven EndoBridge (WEB) device is an intrasaccular flow disruptor designed for wide-necked bifurcation aneurysms. These aneurysms may require the use of a concomitant stent. The objective of this study was to determine the clinical and radiological outcomes of patients undergoing stent-assisted WEB treatment. In addition, the authors also sought to determine the predictors of a concomitant stent in aneurysms treated with the WEB device.

METHODS The data for this study were taken from the WorldWideWEB Consortium, an international multicenter cohort including patients treated with the WEB device. Aneurysms were classified into two groups based on treatment: stent-assisted WEB and WEB device alone. The authors compared clinical and radiological outcomes of both groups. Univariable and multivariable binary logistic regression analyses were performed to determine factors that predispose to stent use.

RESULTS The study included 691 intracranial aneurysms (31 with stents and 660 without stents) treated with the WEB device. The adequate occlusion status did not differ between the two groups at the latest follow-up (83.3% vs 85.6%, p =0.915). Patients who underwent stenting had more thromboembolic (32.3% vs 6.5%, p < 0.001) and procedural (16.1% vs 3.0%, p < 0.001) complications. Aneurysms treated with a concomitant stent had wider necks, greater heights, and lower dome-to-neck ratios. Increasing neck size was the only significant predictor for stent use.

CONCLUSIONS This study demonstrates that there is no difference in the degree of aneurysm occlusion between the two groups; however, complications were more frequent in the stent group. In addition, a wider aneurysm neck predisposes to stent assistance in WEB-treated aneurysms.

Visual Morbidity in Patients With Ophthalmic Segment Aneurysms Treated With Flow Diverters

Neurosurgery 94:538–544, 2024

Flow diverter (FD) treatment for aneurysms of the ophthalmic segment of the internal carotid artery (ICA) may raise concerns about visual morbidity related to coverage of the ophthalmic artery by the device. Our objective was to evaluate clinical and angiographic outcomes associated with FD treatment of these aneurysms, with particular emphasis on visual morbidity.

METHODS: We performed a retrospective analysis of the endovascular databases at 2 US centers to identify consecutive patients with aneurysms along the ophthalmic segment of the ICA that were treated with FDs between January 2010 and December 2022. Baseline demographics, aneurysm characteristics, and periprocedural and postprocedural data, including the occurrence of visual complications, were collected.

RESULTS: One hundred and thirteen patients with 113 aneurysms were identified for inclusion in this study. The mean age of the patients was 59.5 ± 12.4 years, and 103 (91.2%) were women. The ophthalmic artery origin was involved in 40 (35.4%) aneurysms, consisting of a neck origin in 33 (29.2%) and a dome origin in 7 (6.2%). New transient visual morbidity during the hospital stay included impaired visual acuity or blurriness in 1 (0.9%) patient, diplopia in 1 (0.9%), and floaters in 1 (0.9%). New transient visual morbidity during follow-up included impaired visual acuity or blurriness in 5 patients (4.4%), diplopia in 3 (2.7%), ipsilateral visual field defect in 1 (0.9%), and floaters in 6 (5.3%). Permanent visual morbidity occurred in 1 patient (0.9%). Among the 101 patients who had angiographic follow-up, the Raymond-Roy occlusion classifications were I (complete aneurysm occlusion) in 85 (84.2%), II (residual neck) in 11 (10.9%), and III (residual aneurysm) in 5 (4.9%).

CONCLUSION: In our experience, flow diversion for ICA ophthalmic segment aneurysms resulted in low rates of visual morbidity, which was mostly transient in occurrence.

Formation of internal carotid artery aneurysms following gamma knife radiosurgery for pituitary adenomas

Acta Neurochirurgica (2023) 165:2257–2265

Only two aneurysm formations in the internal carotid artery after gamma knife radiosurgery (GKRS) for pituitary adenomas are reported so far.

Here, out of the 482 patients who underwent GKRS for pituitary adenomas at our institute, at least five developed aneurysms within the area of high single-dose irradiation. Three patients presented with epistaxis due to aneurysmal rupture and one presented with abducens paralysis due to nerve compression, while one was asymptomatic.

The interval between irradiation and aneurysmal detection ranged from 14 to 21 years. Aneurysm formation in those conditions may be higher than previously thought.

Cisternal Score: A Radiographic Score to Predict Ventriculoperitoneal Shunt Requirement in Aneurysmal Subarachnoid Hemorrhage

Neurosurgery 93:75–83, 2023

Persistent hydrocephalus requiring a ventriculoperitoneal shunt (VPS) can complicate the management of aneurysmal subarachnoid hemorrhage (aSAH). Identification of high-risk patients may guide external ventricular drain management.

OBJECTIVE: To identify early radiographic predictors for persistent hydrocephalus requiring VPS placement. METHODS: In a 2-center retrospective study, we compared radiographic features on admission noncontrast head computed tomography scans of patients with aSAH requiring a VPS to those who did not, at 2 referral academic centers from 2016 through 2021. We quantified blood clot thickness in the basal cisterns including interpeduncular, ambient, crural, prepontine, interhemispheric cisterns, and bilateral Sylvian fissures. We then created the cisternal score (CISCO) using features that were significantly different between groups.

RESULTS: We included 229 survivors (mean age 55.6 years [SD 13.1]; 63% female) of whom 50 (22%) required VPS. CISCO was greater in patients who required a VPS than those who did not (median 4, IQR 3-6 vs 2, IQR 1-4; P < .001). Higher CISCO was associated with higher odds of developing persistent hydrocephalus with VPS requirement (odds ratio 1.6 per point increase, 95% CI 1.34-1.9; P < .001), independent of age, Hunt and Hess grades, and modified GRAEB scores. CISCO had higher accuracy in predicting VPS requirement (area under the curve 0.75, 95% CI 0.68-0.82) compared with other predictors present on admission.

CONCLUSION: Cisternal blood clot quantification on admission noncontrast head computed tomography scan is feasible and can be used in predicting persistent hydrocephalus with VPS requirement in patients with aSAH. Future prospective studies are recommended to further validate this tool.

Endoscopic clipping of an anterior communicating artery aneurysm

Acta Neurochirurgica (2023) 165:1227–1231

Anterior communicating artery aneurysms are most prone to rupture. Surgically, they are conventionally being managed by a pterional approach. Some neurosurgeons prefer a supraorbital keyhole approach in select cases. Fully endoscopic clipping of such aneurysms is seldom described.

Method We clipped an antero-inferiorly directed anterior communicating artery aneurysm endoscopically via a supraorbital keyhole approach. The intraoperative aneurysmal rupture was also managed endoscopically. The patient made an excellent postoperative recovery without any neurological deficits.

Conclusion Select cases of anterior communicating artery aneurysms can be clipped endoscopically using standard instruments and adhering to the basic principles of aneurysm clipping.

A quantitative model to differentiate nonaneurysmal perimesencephalic subarachnoid hemorrhage from aneurysmal etiology

J Neurosurg 138:165–172, 2023

OBJECTIVE Nonaneurysmal perimesencephalic subarachnoid hemorrhage (pmSAH) is considered to have a lower-risk pattern than other types of subarachnoid hemorrhage (SAH). However, a minority of patients with pmSAH may harbor a causative posterior circulation aneurysm. To exclude this possibility, many institutions pursue exhaustive imaging. In this study the authors aimed to develop a novel predictive model based on initial noncontrast head CT (NCHCT) features to differentiate pmSAH from aneurysmal causes.

METHODS The authors retrospectively reviewed patients admitted to an academic center for treatment of a suspected aneurysmal SAH (aSAH) during the period from 2016 to 2021. Patients with a final diagnosis of pmSAH or posterior circulation aSAH were included. Using NCHCT, the thickness (continuous variable) and location of blood in basal cisterns and sylvian fissures (categorical variables) were compared between groups. A scoring system was created using features that were significantly different between groups. Receiver operating characteristic curve analysis was used to measure the accuracy of this model in predicting aneurysmal etiology. A separate patient cohort was used for external validation of this model.

RESULTS Of 420 SAH cases, 48 patients with pmSAH and 37 with posterior circulation aSAH were identified. Blood thickness measurements in the crural and ambient cisterns and interhemispheric and sylvian fissures and degree of extension into the sylvian fissure were all significantly different between groups (all p < 0.001). The authors developed a 10-point scoring model to predict aneurysmal causes with high accuracy (area under the curve [AUC] 0.99; 95% CI 0.98–1.00; OR per point increase 10; 95% CI 2.18–46.4). External validation resulted in persistently high accuracy (AUC 0.97; 95% CI 0.92–1.00) of this model.

CONCLUSIONS A risk stratification score using initial blood clot burden may accurately differentiate between aneurysmal and nonaneurysmal pmSAH. Larger prospective studies are encouraged to further validate this quantitative tool.

Prevalence of incidental intracranial findings on magnetic resonance imaging: a systematic review and meta‑analysis

Acta Neurochirurgica (2022) 164:2751–2765

As the volume and fidelity of magnetic resonance imaging (MRI) of the brain increase, observation of incidental findings may also increase. We performed a systematic review and meta-analysis to determine the prevalence of various incidental findings.

Methods PubMed/MEDLINE, EMBASE and SCOPUS were searched from inception to May 24, 2021. We identified 6536 citations and included 35 reports of 34 studies, comprising 40,777 participants. A meta-analysis of proportions was performed, and age-stratified estimates for each finding were derived from age-adjusted non-linear models.

Results Vascular abnormalities were observed in 423/35,706 participants (9.1/1000 scans, 95%CI 5.2–14.2), ranging from 2/1000 scans (95%CI 0–7) in 1-year-olds to 16/1000 scans (95%CI 1–43) in 80-year-olds. Of these, 204/34,306 were aneurysms (3.1/1000 scans, 95%CI 1–6.3), which ranged from 0/1000 scans (95%CI 0–5) at 1 year of age to 6/1000 scans (95%CI 3–9) at 60 years. Neoplastic abnormalities were observed in 456/39,040 participants (11.9/1000 scans, 95%CI 7.5–17.2), ranging from 0.2/1000 scans (95%CI 0–10) in 1-year-olds to 34/1000 scans (95%CI 12–66) in 80-year-olds. Meningiomas were the most common, in 246/38,076 participants (5.3/1000 scans, 95%CI 2.3–9.5), ranging from 0/1000 scans (95%CI 0–2) in 1-year-olds to 17/1000 scans (95%CI 4–37) in 80-year-olds. Chiari malformations were observed in 109/27,408 participants (3.7/1000 scans, 95%CI 1.8–6.3), pineal cysts in 1176/32,170 (9/1000 scans, 95%CI 1.8–21.4) and arachnoid cysts in 414/36,367 (8.5/1000 scans, 95%CI 5.8–11.8).

Conclusion Incidental findings are common on brain MRI and may result in substantial resource expenditure and patient anxiety but are often of little clinical significance.

Microsurgical treatment of ruptured aneurysms beyond 72 hours after rupture: implications for advanced management

Acta Neurochirurgica (2022) 164:2431–2439

Aneurysmal subarachnoid hemorrhage (aSAH) patients admitted to primary stroke centers are often transferred to neurosurgical and endovascular services at tertiary centers. The effect on microsurgical outcomes of the resultant delay in treatment is unknown. We evaluated microsurgical aSAH treatment > 72 h after the ictus.

Methods All aSAH patients treated at a single tertiary center between August 1, 2007, and July 31, 2019, were retrospectively reviewed. The additional inclusion criterion was the availability of treatment data relative to time of bleed. Patients were grouped based on bleed-to-treatment time as having acute treatment (on or before postbleed day [PBD] 3) or delayed treatment (on or after PBD 4). Propensity adjustments were used to correct for statistically significant confounding covariables.

Results Among 956 aSAH patients, 92 (10%) received delayed surgical treatment (delayed group), and 864 (90%) received acute endovascular or surgical treatment (acute group). Reruptures occurred in 3% (26/864) of the acute group and 1% (1/92) of the delayed group (p = 0.51). After propensity adjustments, the odds of residual aneurysm (OR = 0.09; 95% CI = 0.04–0.17; p < 0.001) or retreatment (OR = 0.14; 95% CI = 0.06–0.29; p < 0.001) was significantly lower among the delayed group. The OR was 0.50 for rerupture, after propensity adjustments, in the delayed setting (p = 0.03). Mean Glasgow Coma Scale scores at admission in the acute and delayed groups were 11.5 and 13.2, respectively (p < 0.001).

Conclusions Delayed microsurgical management of aSAH, if required for definitive treatment, appeared to be noninferior with respect to retreatment, residual, and rerupture events in our cohort after adjusting for initial disease severity and significant confounding variables.

Solid vs. cystic predominance in posterior fossa hemangioblastomas: implications for cerebrovascular risks and patient outcome

Acta Neurochirurgica (2022) 164:1357–1364

Hemangioblastomas (HGBs) are highly vascular benign tumors, commonly located in the posterior fossa, and 80% of them are sporadic. Patients usually present with features of raised intracranial pressure and cerebellar symptoms. HGB can be classified as either mostly cystic or solids. Although the solid component is highly vascularized, aneurysm or hemorrhagic presentation is rarely described, having catastrophic results.

Methods We identified 32 consecutive patients with posterior fossa HBG who underwent surgery from 2008 through 2020 at our medical center. Tumors were classified as predominantly cystic or solid according to radiological features. Resection was defined as gross total (GTR) or subtotal (STR).

Results During the study period, 32 posterior fossa HGBs were resected. There were 26 cerebellar lesions and 4 medullar lesions, and in 2 patients, both structures were affected. Predominant cystic tumors were seen in 15 patients and solids in 17. Preoperative digital subtraction angiography (DSA) was performed in 8 patients with solid tumors, and 4 showed tumor-related aneurysms. Embolization of the tumors was performed in 6 patients, including the four tumor-related aneurysms. GTR was achieved in 29 tumors (91%), and subtotal resection in 3 (9%). Three patients had postoperative lower cranial nerve palsy. Functional status was stable in 5 patients (16%), improved in 24 (75%), and 3 patients (9%) deteriorated. One patient died 2 months after the surgery. Two tumors recurred and underwent a second surgery achieving GTR. The mean follow-up was 42.7 months (SD ± 51.0 months).

Conclusions Predominant cystic HGB is usually easily treated as the surgery is straightforward. Those with a solid predominance present a more complex challenge sharing features similar to arteriovenous malformations. Given the important vascular association of solid predominance HGB with these added risk factors, the preoperative assessment should include DSA, as in arteriovenous malformations, and endovascular intervention should be considered before surgery.

Keywords

Clipping Could Be the Best Treatment Modality for Recurring Anterior Communicating Artery Aneurysms Treated Endovascularly

Neurosurgery 90:627–635, 2022

The anterior communicating artery (AcoA) is the most common location for intracranial aneurysms.

OBJECTIVE: To present occlusion outcomes, complication rate, recurrence rate, and predictors of recurrence in a large cohort with AcoA aneurysms treated primarily with endosaccular embolization. We also attempt to present data on the most effective treatment modality for recurrent AcoA aneurysms.

METHODS: This is a retrospective, single-center study, reviewing the outcomes of 463 AcoA aneurysms treated endovascularly between 2003 and 2018.

RESULTS: The study cohort consisted of 463 patients. Adequate immediate occlusion was achieved in 418 (90.3%). Independent functional status at discharge was observed in 269 patients (58.0%), and the mortality rate was 6.8% (31). At 6 months, adequate occlusion was achieved in 418 (90.4%). Of all the patients, recurrence was observed in 101 cases (21.8%), and of those, 98 (22.4%) underwent retreatment. The combined frequency of retreatment for the coiling group was 42.4%, which was significantly higher than the 0 incident of retreatment in the clipping group (P < .0001). Among the retreatment cohort, there was a significantly higher subsequent retreatment rate in the endovascular group (0% in the clipping group vs 42.4% in the endovascular group, P < .0001).

CONCLUSION: Coiling with and without stent/balloon assistance is a relatively safe and effective modality for the treatment of AcoA aneurysms; however, in the setting of recurrence, microsurgical reconstruction leads to improved outcomes regarding durable occlusion, thus avoiding the potential for multiple interventions in the future.

The added value of cerebrospinal fluid analysis in patients with subarachnoid hemorrhage after negative noncontrast CT

J Neurosurg 136:1024–1028, 2022

In patients presenting within 6 hours after signs and symptoms of suspected subarachnoid hemorrhage (SAH), CSF examination is judged to be no longer necessary if a noncontrast CT (NCCT) scan rules out SAH. In this study, the authors evaluated the performance of NCCT to rule out SAH in patients with positive CSF findings.

METHODS Between January 2006 and April 2018, 1657 patients were admitted with a nontraumatic SAH. Of these patients, 1546 had positive SAH findings on the initial NCCT and 111 patients had an NCCT scan that was reported as negative in the acute setting, but with positive CSF examination for subarachnoid blood. Demographic data, World Federation of Neurosurgical Societies grade, and SAH time points (ictus, time of NCCT, and time of lumbar puncture) were collected. All 111 NCCT scans were reevaluated by an experienced neuroradiologist.

RESULTS Of the 111 patients with positive CSF findings, SAH was initially missed on NCCT in 25 patients (23%). Reevaluation of 21 patients presenting within 6 hours of symptom onset confirmed NCCT negative findings in 12 (5 aneurysms), an aneurysmal SAH (aSAH) pattern in 8 (7 aneurysms), and a perimesencephalic pattern in 1 patient. Reevaluation of 90 patients presenting after 6 hours confirmed negative NCCT findings in 74 patients (37 aneurysms), aSAH pattern in 10 (4 aneurysms), and a perimesencephalic pattern in 6 (2 aneurysms).

CONCLUSIONS CSF examination is still mandatory to rule out SAH as NCCT can fail to show blood, even within 6 hours after symptom onset. In addition, the diagnosis SAH was frequently missed during initial reporting.

Safety, Efficacy, and Durability of Stent Plus Balloon-Assisted Coiling for the Treatment of Wide-Necked Intracranial Bifurcation Aneurysms

Neurosurgery 88:1028–1037, 2021

Wide-necked bifurcation aneurysms remain a challenge for endovascular surgeons. Dual-stent-assisted coiling techniques have been defined to treat bifurcation aneurysms with a complex neck morphology. However, there are still concerns about the safety of dual-stenting procedures. Stent plus balloon-assisted coiling is a recently described endovascular technique that enables the coiling of wide-necked complex bifurcation aneurysms by implanting only a single stent.

OBJECTIVE: To investigate the feasibility, efficacy, safety, and durability of this technique for the treatment of wide-necked bifurcation aneurysms.

METHODS: A retrospective review was performed of patients with wide-necked intracranial bifurcation aneurysms treated with stent plus balloon-assisted coiling. The initial and follow-up clinical and angiographic outcomeswere assessed. Preprocedural and follow-up clinical statuses were assessed using modified Rankin scale.

RESULTS: A total of 61 patients (mean age: 54.6 ± 10.4 yr) were included in the study. The immediate postprocedural digital subtraction angiography revealed complete aneurysm occlusion in 86.9% of the cases. A periprocedural complication developed in 11.5% of the cases. We observed a delayed ischemic complication in 4.9%. There was no mortality in this study. The permanent morbidity rate was 3.3%. The follow-up angiography was performed in 55 of 61 patients (90.1%) (the mean follow-up period was 25.5 ± 27.3 mo). The rate of complete aneurysm occlusion at the final angiographic follow-up was 89.1%. The retreatment rate was 1.8%.

CONCLUSION: The results of this study showed that stent plus balloon-assisted coiling is a feasible, effective, and relatively safe endovascular technique for the treatment of widenecked bifurcation aneurysms located in the posterior and anterior circulation.

Stent PlusBalloon-Assisted Coiling for the Treatment ofWide-Necked Intracranial Bifurcation Aneurysms

Neurosurgery 88:1028–1037, 2021

Wide-necked bifurcation aneurysms remain a challenge for endovascular surgeons. Dual-stent-assisted coiling techniques have been defined to treat bifurcation aneurysms with a complex neck morphology. However, there are still concerns about the safety of dual-stenting procedures. Stent plus balloon-assisted coiling is a recently described endovascular technique that enables the coiling of wide-necked complex bifurcation aneurysms by implanting only a single stent.

OBJECTIVE:To investigate the feasibility, efficacy, safety, and durability of this technique for the treatment of wide-necked bifurcation aneurysms.

METHODS:A retrospective review was performed of patients with wide-necked intracranial bifurcation aneurysms treated with stent plus balloon-assisted coiling. The initial and follow-up clinical and angiographic outcomes were assessed. Preprocedural and follow-up clinical statuses were assessed using modified Rankin scale.

RESULTS:A total of 61 patients (mean age: 54.6±10.4 yr) were included in the study. The immediate postprocedural digital subtraction angiography revealed complete aneurysm occlusion in 86.9% of the cases. A periprocedural complication developed in 11.5% of the cases. We observed a delayed ischemic complication in 4.9%. There was no mortality in this study. The permanent morbidity rate was 3.3%. The follow-up angiography was performed in 55 of 61 patients (90.1%) (the mean follow-up period was 25.5±27.3 mo).The rate of complete aneurysm occlusion at the final angiographic follow-up was 89.1%. The retreatment rate was 1.8%.

CONCLUSION:The results of this study showed that stent plus balloon-assisted coiling is a feasible, effective, and relatively safe endovascular technique for the treatment of wide-necked bifurcation aneurysms located in the posterior and anterior circulation.

 

Comparative anatomical analysis between the minipterional and supraorbital approaches

J Neurosurg 134:1276–1284, 2021

Keyhole approaches, namely the minipterional approach (MPTa) and the supraorbital approach (SOa), are alternatives to the standard pterional approach to treat lesions located in the anterior and middle cranial fossae. Despite their increasing popularity and acceptance, the indications and limitations of these approaches require further assessment. The purpose of the present study was to determine the differences in the area of surgical exposure and surgical maneuverability provided by the MPTa and SOa.

METHODS The areas of surgical exposure afforded by the MPTa and SOa were analyzed in 12 sides of cadaver heads by using a microscope and a neuronavigation system. The area of exposure of the region of interest and surgical freedom (maneuverability) of each approach were calculated.

RESULTS The area of exposure was significantly larger in the MPTa than in the SOa (1250 ± 223 mm2 vs 939 ± 139 mm2, p = 0.002). The MPTa provided larger areas of exposure in the ipsilateral and midline compartments, whereas there was no significant difference in the area of exposure in the contralateral compartment. All targets in the anterior circulation had significantly larger areas of surgical freedom when treated via the MPTa versus the SOa.

CONCLUSIONS The MPTa provides greater surgical exposure and better maneuverability than that offered by the SOa. The SOa may be advantageous as a direct corridor for treating lesions located in the contralateral side or in the anterior cranial fossa, but the surgical exposure provided in the midline region is inferior to that exposed by the MPTa.

The endoscopic supraorbital translaminar approach

Acta Neurochirurgica (2021) 163:635–641

Resection of lesions located within the third ventricle presents a surgical challenge. Several approaches have been developed in an attempt to obtain maximal resection, while minimizing brain retraction. In this work, we assess the surgical exposure and maneuverability of the endoscopic supraorbital translaminar approach (ESTA), a potential alternative to fenestrate the lamina terminalis and approach the third ventricle by using the endoscope through a keyhole supraorbital-eyebrow craniotomy.

Methods Five cadaveric heads were used to assess the corridor depth, area of exposure, and viewing angles offered by the ESTA. One additional utilized specimen provided a stepwise dissection of the approach.

Results The ESTA was successfully performed in all specimens. Depth of the surgical corridor from the craniotomy to the ipsilateral internal carotid artery (ICA), lamina terminalis, and contralateral carotid were 70.7 ± 2.9 mm, 73.2 ± 2.9 mm, and 78.9 ± 4.1 mm, respectively. Viewing angle referenced to the ipsilateral ICA was 6.5 ± 4.2°, while the viewing angle for the lamina terminalis was 25.8 ± 4.3°. The surgical exposure provided by the ESTA was 1655 ± 255 mm2.

Conclusions The ESTA provides a wide surgical view of the lamina terminalis and may be potentially used to approach lesions located in the anterior third of the third ventricle. As a pure endoscopic approach, the ESTA requires minimal brain retraction, while affords good visualization of targeted lesions around the lamina terminalis. The ESTA uses an anterolateral approach and so provides a short and straightforward approach to these structures.

Early postmarket results with PulseRider for treatment of wide-necked intracranial aneurysms: a multicenter experience

J Neurosurg 133:1756–1765, 2020

Traditionally, stent-assisted coiling and balloon remodeling have been the primary endovascular treatments for wide-necked intracranial aneurysms with complex morphologies. PulseRider is an aneurysm neck reconstruction device that provides parent vessel protection for aneurysm coiling. The objective of this study was to report early postmarket results with the PulseRider device.

METHODS This study was a prospective registry of patients treated with PulseRider at 13 American neurointerventional centers following FDA approval of this device. Data collected included clinical presentation, aneurysm characteristics, treatment details, and perioperative events. Follow-up data included degree of aneurysm occlusion and delayed (> 30 days after the procedure) complications.

RESULTS A total of 54 aneurysms were treated, with the same number of PulseRider devices, across 13 centers. Fourteen cases were in off-label locations (7 anterior communicating artery, 6 middle cerebral artery, and 1 A1 segment anterior cerebral artery aneurysms). The average dome/neck ratio was 1.2. Technical success was achieved in 52 cases (96.2%). Major complications included the following: 3 procedure-related posterior cerebral artery strokes, a devicerelated intraoperative aneurysm rupture, and a delayed device thrombosis. Immediately postoperative Raymond-Roy occlusion classification (RROC) class 1 was achieved in 21 cases (40.3%), class 2 in 15 (28.8%), and class 3 in 16 cases (30.7%). Additional devices were used in 3 aneurysms. For those patients with 3- or 6-month angiographic follow-up (28 patients), 18 aneurysms (64.2%) were RROC class 1 and 8 (28.5%) were RROC class 2.

CONCLUSIONS PulseRider is being used in both on- and off-label cases following FDA approval. The clinical and radiographic outcomes are comparable in real-world experience to the outcomes observed in earlier studies. Further experience is needed with the device to determine its role in the neurointerventionalist’s armamentarium, especially with regard to its off-label use.

PulseRider for treatment of wide-necked intracranial aneurysms: a multicenter experience

J Neurosurg 133:1756–1765, 2020

Traditionally, stent-assisted coiling and balloon remodeling have been the primary endovascular treatments for wide-necked intracranial aneurysms with complex morphologies. PulseRider is an aneurysm neck reconstruction device that provides parent vessel protection for aneurysm coiling. The objective of this study was to report early postmarket results with the PulseRider device.

METHODS This study was a prospective registry of patients treated with PulseRider at 13 American neurointerventional centers following FDA approval of this device. Data collected included clinical presentation, aneurysm characteristics, treatment details, and perioperative events. Follow-up data included degree of aneurysm occlusion and delayed (> 30 days after the procedure) complications.

RESULTS A total of 54 aneurysms were treated, with the same number of PulseRider devices, across 13 centers. Fourteen cases were in off-label locations (7 anterior communicating artery, 6 middle cerebral artery, and 1 A1 segment anterior cerebral artery aneurysms). The average dome/neck ratio was 1.2. Technical success was achieved in 52 cases (96.2%). Major complications included the following: 3 procedure-related posterior cerebral artery strokes, a devicerelated intraoperative aneurysm rupture, and a delayed device thrombosis. Immediately postoperative Raymond-Roy occlusion classification (RROC) class 1 was achieved in 21 cases (40.3%), class 2 in 15 (28.8%), and class 3 in 16 cases (30.7%). Additional devices were used in 3 aneurysms. For those patients with 3- or 6-month angiographic follow-up (28 patients), 18 aneurysms (64.2%) were RROC class 1 and 8 (28.5%) were RROC class 2.

CONCLUSIONS PulseRider is being used in both on- and off-label cases following FDA approval. The clinical and radiographic outcomes are comparable in real-world experience to the outcomes observed in earlier studies. Further experience is needed with the device to determine its role in the neurointerventionalist’s armamentarium, especially with regard to its off-label use.