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Cover Neurosurgical Focus: Video

Introduction. Flow diversion for cerebral aneurysms

Peter T. Kan, Elad I. Levy, Felipe C. Albuquerque, and Mandy Jo Binning

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Cover Journal of Neurosurgery

Oligodendroglioma and juvenile pilocytic astrocytoma presenting as synchronous primary brain tumors

Case report with histological and molecular differentiation of the tumors and review of the literature

Peter Kan, Oren Gottfried, Deborah T. Blumenthal, Jeannette J. Townsend, Ela Drozd-Borysiuk, Arthur R. Brothman, and Randy L. Jensen

✓ Multiple metastatic brain tumors and multifocal primary brain tumors of a single histological type are well described in the literature. The concurrent presence of multiple primary brain tumors with different histological characteristics, however, is very rare. The authors describe the first known case in which an oligodendroglioma and a juvenile pilocytic astrocytoma (JPA) presented as synchronous primary brain tumors in the same patient.

This 43-year-old man presented with a 2-month history of progressive headaches, nausea, and vomiting. Magnetic resonance imaging demonstrated an enhancing heterogeneous right medial cerebellar lesion and a larger calcified, nonenhancing, heterogeneous right frontal lesion with surrounding edema and a mass effect. The results of a metastatic workup were unremarkable.

The patient underwent an initial right frontotemporal craniotomy and a subsequent suboccipital craniectomy 2 years later for resection of the posterior fossa lesion. Histological examination revealed the frontal and cerebellar lesions to be an oligodendroglioma and JPA, respectively. A molecular analysis detected a deletion of chromosome 1p36 in the oligodendroglioma, but not in the JPA. After the initial operation, the patient received follow-up care for his oligodendroglioma, but eventually required temozolomide for tumor progression. His condition remains stable both neurologically and according to imaging studies.

The authors describe the first known case in which a low-grade oligodendroglioma and a JPA presented as synchronous primary brain tumors. They review the literature on multiple primary brain tumors with different histological characteristics and discuss potential mechanisms for the development of these lesions.

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Cover Journal of Neurosurgery

The neurosurgical marriage: evaluating the interplay of work life and home life from the perspective of partners of neurosurgical residents

William J. Ares, Brian T. Jankowitz, Peter Kan, Alejandro M. Spiotta, Peter Nakaji, Jason D. Wilson, Kyle M. Fargen, Edwin Ramos, Jody Leonardo, and Ramesh Grandhi

OBJECTIVE

Burnout and work-life balance have been noted to be problems for residents across all fields of medicine, including neurosurgery. No studies to date have evaluated how these factors may contribute to issues outside of the hospital, specifically residents’ home lives. This study aimed to evaluate the interplay between home life and work life of neurosurgical residents, specifically from the point of view of residents’ significant others.

METHODS

Online surveys were distributed to the significant others of neurosurgical residents at 12 US neurosurgery residencies. Residents’ partners were asked about relationship dynamics, their views on neurosurgery residency (work-life balance and burnout), and their views of neurosurgery as a career.

RESULTS

The majority of residents’ significant others (84%) reported being satisfied with their relationship. Significant others who reported dissatisfaction with their relationship were more likely to report frustration with work-life balance and more likely to report their resident partner as having higher levels of burnout.

CONCLUSIONS

From the perspective of neurosurgery residents’ significant others, higher perceived levels of burnout and lower satisfaction with work-life balance are correlated with lower levels of relationship satisfaction. These findings speak to the complex interplay of work life and home life and can be used to inform future interventions into improving the quality of life for both the resident and the significant other.

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Cover Journal of Neurosurgery

The natural history of aneurysms incompletely occluded by placement of a flow diverter: a multiinstitutional study

Peter Theiss, Ahmed Essam Ali, Laura Stone McGuire, Giuseppe Lanzino, Sherief Ghozy, Waleed Brinjikji, Kareem El Naamani, Abdelaziz Amllay, Stavropoula I. Tjoumakaris, Pascal Jabbour, Mohamed M. Salem, Jan-Karl Burkhardt, Brian T. Jankowitz, Adib Abla, Daniel A. Tonetti, Peter T. Kan, Ariadna Robledo, and Ali Alaraj

OBJECTIVE

Treatment of intracranial aneurysms by flow diversion is safe and effective and is increasingly popular. However, the correct treatment paradigm for aneurysms incompletely treated by initial placement of a flow diverter has not been established, nor have the subsequent natural history and occlusion rates of such aneurysms. The authors sought to outline the natural history of such aneurysms, which to date have been considered partially treated.

METHODS

The authors retrospectively reviewed consecutive cases from 6 high-volume neurointerventional services, including all cases in which the first follow-up imaging after placement of a flow diverter showed incomplete occlusion of the aneurysm, and for which subsequent clinical and/or radiological follow-up was available. All included patients were treated with the Pipeline Flex embolization device or the Pipeline Flex embolization device with Shield Technology. Subsequent radiographic and clinical outcome data were collected and analyzed using the Kaplan-Meier survival function.

RESULTS

A total of 263 patients with persistently patent aneurysms on first follow-up imaging after flow diversion were identified. Of these, 204 had clinical follow-up and 152 had additional imaging follow-up. Of this final cohort, 148 aneurysms were unruptured, and 4 were ruptured. The average aneurysm size by maximum dimension was 10.8 mm. The average recorded follow-up was 27.8 months in the cohort, with some patients followed for as long as 9 years from treatment. Over the course of 403 person-years of follow-up, no delayed aneurysm ruptures were recorded. Both with and without retreatment, aneurysms showed a trend toward progressive occlusion over time. Complications related to device placement were low.

CONCLUSIONS

Aneurysms that have been incompletely treated by flow diversion have a benign natural history with progression toward occlusion over time, with or without retreatment.

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Cover Neurosurgical Focus

Middle meningeal artery embolization treatment of nonacute subdural hematomas in the elderly: a multiinstitutional experience of 151 cases

Evan Joyce, Michael T. Bounajem, Jonathan Scoville, Ajith J. Thomas, Christopher S. Ogilvy, Howard A. Riina, Omar Tanweer, Elad I. Levy, Alejandro M. Spiotta, Bradley A. Gross, Brian T. Jankowitz, C. Michael Cawley, Alexander A. Khalessi, Aditya S. Pandey, Andrew J. Ringer, Ricardo Hanel, Rafael A. Ortiz, David Langer, Michael R. Levitt, Mandy Binning, Philipp Taussky, Peter Kan, and Ramesh Grandhi

OBJECTIVE

The incidence of already common chronic subdural hematomas (CSDHs) and other nonacute subdural hematomas (NASHs) in the elderly is expected to rise as the population ages over the coming decades. Surgical management is associated with recurrence and exposes elderly patients to perioperative and operative risks. Middle meningeal artery (MMA) embolization offers the potential for a minimally invasive, less morbid treatment in this age group. The clinical and radiographic outcomes after MMA embolization treatment for NASHs have not been adequately described in elderly patients. In this paper, the authors describe the clinical and radiographic outcomes after 151 cases of MMA embolization for NASHs among 121 elderly patients.

METHODS

In a retrospective review of a prospectively maintained database across 15 US academic centers, the authors identified patients aged ≥ 65 years who underwent MMA embolization for the treatment of NASHs between November 2017 and February 2020. Patient demographics, comorbidities, clinical and radiographic factors, treatment factors, and clinical outcomes were abstracted. Subgroup analysis was performed comparing elderly (age 65–79 years) and advanced elderly (age > 80 years) patients.

RESULTS

MMA embolization was successfully performed in 98% of NASHs (in 148 of 151 cases) in 121 patients. Seventy elderly patients underwent 87 embolization procedures, and 51 advanced elderly patients underwent 64 embolization procedures. Elderly and advanced elderly patients had similar rates of embolization for upfront (46% vs 61%), recurrent (39% vs 33%), and prophylactic (i.e., with concomitant surgical intervention; 15% vs 6%) NASH treatment. Transfemoral access was used in most patients, and the procedure time was approximately 1 hour in both groups. Particle embolization with supplemental coils was most common, used in 51% (44/87) and 44% (28/64) of attempts for the elderly and advanced elderly groups, respectively. NASH thickness decreased significantly from initial thickness to 6 weeks, with additional decrease in thickness observed in both groups at 90 days. At longest follow-up, the treated NASHs had stabilized or improved in 91% and 98% of the elderly and advanced elderly groups, respectively, with > 50% improvement seen in > 60% of patients for each group. Surgical rescue was necessary in 4.6% and 7.8% of cases, and the overall mortality was 8.6% and 3.9% for elderly and advanced elderly patients, respectively.

CONCLUSIONS

MMA embolization can be used safely and effectively as an alternative or adjunctive minimally invasive treatment for NASHs in elderly and advanced elderly patients.

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Cover Journal of Neurosurgery: Pediatrics

Prognostic significance of age within the adolescent and young adult acute ischemic stroke population after mechanical thrombectomy: insights from STAR

Victor M. Lu, Evan M. Luther, Michael A. Silva, Turki Elarjani, Ahmed Abdelsalam, Ilko Maier, Sami Al Kasab, Pascal M. Jabbour, Joon-Tae Kim, Stacey Q. Wolfe, Ansaar T. Rai, Marios-Nikos Psychogios, Edgar A. Samaniego, Adam S. Arthur, Shinichi Yoshimura, Jonathan A. Grossberg, Ali Alawieh, Isabel Fragata, Adam Polifka, Justin Mascitelli, Joshua Osbun, Min S. Park, Michael R. Levitt, Travis Dumont, Hugo Cuellar, Richard W. Williamson Jr., Daniele G. Romano, Roberto Crosa, Benjamin Gory, Maxim Mokin, Mark Moss, Kaustubh Limaye, Peter Kan, Dileep R. Yavagal, Alejandro M. Spiotta, and Robert M. Starke

OBJECTIVE

Although younger adults have been shown to have better functional outcomes after mechanical thrombectomy (MT) for acute ischemic stroke (AIS), the significance of this relationship in the adolescent and young adult (AYA) population is not well defined given its undefined rarity. Correspondingly, the goal of this study was to determine the prognostic significance of age in this specific demographic following MT for large-vessel occlusions.

METHODS

A prospectively maintained international multi-institutional database, STAR (Stroke Thrombectomy and Aneurysm Registry), was reviewed for all patients aged 12–18 (adolescent) and 19–25 (young adult) years. Parameters were compared using chi-square and t-test analyses, and associations were interrogated using regression analyses.

RESULTS

Of 7192 patients in the registry, 41 (0.6%) satisfied all criteria, with a mean age of 19.7 ± 3.3 years. The majority were male (59%) and young adults (61%) versus adolescents (39%). The median prestroke modified Rankin Scale (mRS) score was 0 (range 0–2). Strokes were most common in the anterior circulation (88%), with the middle cerebral artery being the most common vessel (59%). The mean onset-to–groin puncture and groin puncture–to-reperfusion times were 327 ± 229 and 52 ± 42 minutes, respectively. The mean number of passes was 2.2 ± 1.2, with 61% of the cohort achieving successful reperfusion. There were only 3 (7%) cases of reocclusion. The median mRS score at 90 days was 2 (range 0–6). Between the adolescent and young adult subgroups, the median mRS score at last follow-up was statistically lower in the adolescent subgroup (1 vs 2, p = 0.03), and older age was significantly associated with a higher mRS at 90 days (coefficient 0.33, p < 0.01).

CONCLUSIONS

Although rare, MT for AIS in the AYA demographic is both safe and effective. Even within this relatively young demographic, age remains significantly associated with improved functional outcomes. The implication of age-dependent stroke outcomes after MT within the AYA demographic needs greater validation to develop effective age-specific protocols for long-term care across both pediatric and adult centers.

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Cover Journal of Neurosurgery

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

Jose Danilo Bengzon Diestro, Mahmoud Dibas, Nimer Adeeb, Robert W. Regenhardt, Justin E. Vranic, Adrien Guenego, Sovann V. Lay, Leonardo Renieri, Ali Al Balushi, Eimad Shotar, Kévin Premat, Kareem El Namaani, Guillaume Saliou, Markus A. Möhlenbruch, Ivan Lylyk, Paul M. Foreman, Jay A. Vachhani, Vedran Župančić, Muhammad U. Hafeez, Caleb Rutledge, Hamid Rai, Vincent M. Tutino, Shervin Mirshahi, Sherief Ghozy, Pablo Harker, Naif M. Alotaibi, James D. Rabinov, Yifan Ren, Clemens M. Schirmer, Oded Goren, Mariangela Piano, Anna L. Kühn, Caterina Michelozzi, Stéphanie Elens, Robert M. Starke, Ameer E. Hassan, Arsalaan Salehani, Anh Nguyen, Jesse Jones, Marios Psychogios, Julian Spears, Thomas Marotta, Vitor Pereira, Carmen Parra-Fariñas, Maria Bres-Bullrich, Michael Mayich, Mohamed M. Salem, Jan-Karl Burkhardt, Brian T. Jankowitz, Ricardo A. Domingo, Thien Huynh, Rabih Tawk, Christian Ulfert, Boris Lubicz, Pietro Panni, Ajit S. Puri, Guglielmo Pero, Christoph J. Griessenauer, Hamed Asadi, Adnan Siddiqui, Andrew F. Ducruet, Felipe C. Albuquerque, Nirav Patel, Peter Kan, Vladimir Kalousek, Pedro Lylyk, Srikanth Boddu, Christopher J. Stapleton, Jared Knopman, Pascal Jabbour, Stavropoula Tjoumakaris, Frédéric Clarençon, Nicola Limbucci, Mohammad A. Aziz-Sultan, Hugo H. Cuellar-Saenz, Christophe Cognard, Aman B. Patel, and Adam A. Dmytriw

OBJECTIVE

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.

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Cover Neurosurgical Focus

Abstracts of the 2017 AANS/CNS Joint Section on Disorders of the Spine and Peripheral Nerves Las Vegas, Nevada • March 8–11, 2017

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Cover Journal of Neurosurgery

Oral Presentations 2015 AANS Annual Scientific Meeting Washington, DC • May 2–6, 2015

Published online August 1, 2015; DOI: 10.3171/2015.8.JNS.AANS2015abstracts

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Cover Journal of Neurosurgery

Oral Presentations 2016 AANS Annual Scientific Meeting Chicago, IL • April 30–May 4, 2016

Published online April 1, 2016; DOI: 10.3171/2016.4.JNS.AANS2016abstracts