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Label-free microscopic assessment of glioblastoma biopsy specimens prior to biobanking

Joseph Georges, Aqib Zehri, Elizabeth Carlson, Joshua Nichols, Michael A. Mooney, Nikolay L. Martirosyan, Layla Ghaffari, M. Yashar S. Kalani, Jennifer Eschbacher, Burt Feuerstein, Trent Anderson, Mark C. Preul, Kendall Van Keuren-Jensen, and Peter Nakaji

Glioblastoma is the most common primary brain tumor with a median 12- to 15-month patient survival. Improving patient survival involves better understanding the biological mechanisms of glioblastoma tumorigenesis and seeking targeted molecular therapies. Central to furthering these advances is the collection and storage of surgical biopsies (biobanking) for research. This paper addresses an imaging modality, confocal reflectance microscopy (CRM), for safely screening glioblastoma biopsy samples prior to biobanking to increase the quality of tissue provided for research and clinical trials. These data indicate that CRM can immediately identify cellularity of tissue biopsies from animal models of glioblastoma. When screening fresh human biopsy samples, CRM can differentiate a cellular glioblastoma biopsy from a necrotic biopsy without altering DNA, RNA, or protein expression of sampled tissue. These data illustrate CRM's potential for rapidly and safely screening clinical biopsy samples prior to biobanking, which demonstrates its potential as an effective screening technique that can improve the quality of tissue biobanked for patients with glioblastoma.

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Seven bypasses simulation set: description and validity assessment of novel models for microneurosurgical training

Evgenii Belykh, Irakliy Abramov, Liudmila Bardonova, Ruchi Patel, Sarah McBryan, Lara Enriquez Bouza, Neil Majmundar, Xiaochun Zhao, Vadim A. Byvaltsev, Stephen A. Johnson, Amit Singla, Gaurav Gupta, Hai Sun, James K. Liu, Anil Nanda, Mark C. Preul, and Michael T. Lawton

OBJECTIVE

Microsurgical training remains indispensable to master cerebrovascular bypass procedures, but simulation models for training that accurately replicate microanastomosis in narrow, deep-operating corridors are lacking. Seven simulation bypass scenarios were developed that included head models in various surgical positions with premade approaches, simulating the restrictions of the surgical corridors and hand positions for microvascular bypass training. This study describes these models and assesses their validity.

METHODS

Simulation models were created using 3D printing of the skull with a designed craniotomy. Brain and external soft tissues were cast using a silicone molding technique from the clay-sculptured prototypes. The 7 simulation scenarios included: 1) temporal craniotomy for a superficial temporal artery (STA)–middle cerebral artery (MCA) bypass using the M4 branch of the MCA; 2) pterional craniotomy and transsylvian approach for STA-M2 bypass; 3) bifrontal craniotomy and interhemispheric approach for side-to-side bypass using the A3 branches of the anterior cerebral artery; 4) far lateral craniotomy and transcerebellomedullary approach for a posterior inferior cerebellar artery (PICA)–PICA bypass or 5) PICA reanastomosis; 6) orbitozygomatic craniotomy and transsylvian-subtemporal approach for a posterior cerebral artery bypass; and 7) extended retrosigmoid craniotomy and transcerebellopontine approach for an occipital artery–anterior inferior cerebellar artery bypass. Experienced neurosurgeons evaluated each model by practicing the aforementioned bypasses on the models. Face and content validities were assessed using the bypass participant survey.

RESULTS

A workflow for model production was developed, and these models were used during microsurgical courses at 2 neurosurgical institutions. Each model is accompanied by a corresponding prototypical case and surgical video, creating a simulation scenario. Seven experienced cerebrovascular neurosurgeons practiced microvascular anastomoses on each of the models and completed surveys. They reported that actual anastomosis within a specific approach was well replicated by the models, and difficulty was comparable to that for real surgery, which confirms the face validity of the models. All experts stated that practice using these models may improve bypass technique, instrument handling, and surgical technique when applied to patients, confirming the content validity of the models.

CONCLUSIONS

The 7 bypasses simulation set includes novel models that effectively simulate surgical scenarios of a bypass within distinct deep anatomical corridors, as well as hand and operator positions. These models use artificial materials, are reusable, and can be implemented for personal training and during microsurgical courses.

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Abstracts for the 2013 Annual Meeting of The American Society of Pediatric Neurosurgeons

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Abstracts of the 2014 Annual Meeting of the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves Orlando, Florida • March 5–8, 2014

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AANS/CNS Cerebrovascular Section Meeting February 2011

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Abstracts of the 2013 Annual Meeting of the AANS/CNS Section on Disorders of the Spine and Peripheral Nerves

Phoenix, Arizona • March 6–9, 2013

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Oral Presentations

2010 AANS Annual Meeting Philadelphia, Pennsylvania May 1–5, 2010

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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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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

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2017 AANS Annual Scientific Meeting Los Angeles, CA • April 22–26, 2017