Michael Avery

Interests

Teaching

Anatomical/cadaveric teaching, clinical teaching with an emphasis on vascular/endovascular and skull base pathologies

Research

Stroke and aneurysm treatment outcomes;Optimizing peri-operative outcomes for skull base tumor surgery;Improving endoscopic techniques

Courses

No activities entered.

Scholarly Contributions

Chapters

• Avery, M. (2021). Cerebral vasospasm. In Neurointerventional Surgery: An Evidence Based Approach, 1st Ed..
• Avery, M. (2022). Endoscopic endonasal approaches. In Youssef S et al (Eds). . In Contemporary Skull base Surgery: A Comprehensive Guide to Functional Preservation.
• Avery, M. (2022). Pituitary surgery. In De Groot’s Endocrinology: Basic Science and Clinical Practice, 8th Ed..
• Avery, M. (2022). Principles of skull base reconstruction. In Contemporary Skull base Surgery: A Comprehensive Guide to Functional Preservation.
• Avery, M. B., Barkhoudarian, G., Kelly, D. F., & Griffiths, C. (2022). Endoscopic Endonasal Approaches. In Contemporary Skull Base Surgery: A Comprehensive Guide to Functional Preservation. Springer International Publishing. doi:10.1007/978-3-030-99321-4_15
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  Pathologies of the anterior skull base, including the cribriform plate, planum sphenoidale, and tuberculum sellae, have traditionally been approached through several transcranial and transfacial approaches. More recently, keyhole approaches have been utilized with success even for large tumors, avoiding the morbidity of larger exposures and minimizing brain exposure and retraction. Endoscopic endonasal approaches are an extension of this philosophy and, in carefully selected patients, may be an excellent alternative, offering a direct line of site from an endonasal trajectory. Furthermore, bilateral optic canal decompression can be safely and effectively accomplished via the endonasal route. Here, we describe the endoscopic endonasal transtuberculum/transplanum and transcribriform approaches, focusing on indications, limitations, functional preservation techniques, and complication avoidance. In the theme of functional preservation, we also propose that the supraorbital keyhole craniotomy be considered as an alternative to the transcribriform approach to preserve olfaction.
• Barkhoudarian, G., Avery, M. B., & Kelly, D. F. (2022). Principles of Skull Base Reconstruction. In Contemporary Skull Base Surgery: A Comprehensive Guide to Functional Preservation. Springer International Publishing. doi:10.1007/978-3-030-99321-4_10
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  Skull base reconstruction requires a comprehensive approach to achieve adequate closure and prevent CSF leakage. Nearly always, a multilayered approach utilizing a combination of autograft and allograft is implemented. There may be multiple skull base approaches for a given pathology, and the reconstruction options are a major factor in this selection. Function preservation must be considered, avoiding destructive techniques when possible. Although reconstruction options vary based on surgical approach, common concepts include collagen inlay, fat graft placement, rigid (permanent or removable) buttress, and early mobilization. Implementation of ERAS principles is helpful to maximize chances of positive outcomes.
• Avery, M., Ogilvy, C., & Mitha, A. (2017). Cerebrovascular disease. In Reference Collection in Neuroscience and Biobehavioral Psychology. doi:10.1016/B978-0-12-809324-5.02031-9
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  This article consists of a general overview of brain and spinal cord vascular diseases, including occlusive diseases, vascular malformations of the brain and spine, and vascular pathologies related to trauma. Important features of the presenting symptoms, diagnosis, and pathophysiology of these diseases are discussed. Typical management techniques are also highlighted, with a focus on current surgical and endovascular treatment methods.

Journals/Publications

• Barkhoudarian, G., Zhou, D., Avery, M. B., Khan, U., Mallari, R. J., Emerson, J., Griffiths, C., & Kelly, D. F. (2025). Comparative Analysis of Endoscope Obscuration with Utilization of an Endonasal Access Guide for Endonasal Skull Base Surgery. Operative Neurosurgery, 28(Issue 2). doi:10.1227/ons.0000000000001267
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  BACKGROUND AND OBJECTIVES:In endoscopic endonasal approaches (EEAs) for skull base pathologies, endoscope view obscuration remains a persistent, time-consuming, and distracting issue for surgeons and may result in increased operative time. The endonasal access guide (EAG) has been demonstrated as a possible adjunct to minimize these events. However, to date, there have been no comparative studies performed and the potential time savings by using EAGs have yet to be quantified. This cohort study aimed to determine the operative efficiency benefits of the EAG in EEA operations.METHODS:Analysis of EEA operative videos from an EAG cohort (n = 20) and a control cohort (n = 20) was performed, assessing 12-minute segments in the first, middle, and last third of each operation. The first segment in each cohort was selected before EAG placement, serving as an internal control. Every endoscope lens soiling instance was counted (measured as cleaning actions per minute), timed (obscuration time %), and identified as a withdrawal, irrigation, or other cleaning action. Perioperative variables including skull base repair and postoperative cerebrospinal fluid leakage were assessed.RESULTS:Within the EAG cohort, obscuration time was reduced in the middle and last third compared with the first third (3.73% [CI: 2.39-5.07] vs 12.97% [CI: 10.24-15.70], P
• Samargandy, S., Ahmadian, D., Zhang, J., Biffar, D., Avery, M. B., Le, C., & Chang, E. (2025). Incorporating HTA and VR Simulation to Teach Trainees in Endoscopic Endonasal Skull Base Approaches. Laryngoscope. doi:10.1002/lary.70188
• Avery, M. (2016). Intra-operative indocyanine green videoangiography to guide decision making regarding need for vessel bypass: a case report and technical note. Surg Neurol Int.
• Avery, M. (2021). Endoscopic endonasal surgery for anterior skull base meningiomas. Mini-invasive Surg, 17.
• Barkhoudarian, G., Zhou, D., Avery, M., Khan, U., Mallari, R. J., Emerson, J., Griffiths, C., & Kelly, D. F. (2024). Comparative analysis of endoscope obscurations with utilization of an endonasal access guide for endonasal skull base surgery . Operative Neurosurgery.
• Campos, J. K., Meyer, B. M., Zarrin, D. A., Khan, M. W., Collard de Beaufort, J. C., Amin, G., Avery, M. B., Golshani, K., Beaty, N. B., Bender, M. T., Colby, G. P., Lin, L. M., & Coon, A. L. (2024). Immediate procedural safety of adjunctive proximal coil occlusion in middle meningeal artery embolization for chronic subdural hematomas: Experience in 137 cases. Interventional Neuroradiology. doi:10.1177/15910199231224003
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  Background: Endovascular embolization of the middle meningeal artery (MMA) has emerged as an adjunctive and stand-alone modality for the management of chronic subdural hematomas (cSDH). We report our experience utilizing proximal MMA coil embolization to augment cSDH devascularization in MMA embolization. Methods: MMA embolization cases with adjunctive proximal MMA coiling were retrospectively identified from a prospectively maintained IRB-approved database of the senior authors. Results: Of the 137 cases, all patients (n = 89, 100%) were symptomatic and underwent an MMA embolization procedure for cSDH. 50 of the patients underwent bilateral embolizations, with 53% (n = 72) for left-sided and 47% (n = 65) for right-sided cSDH. The anterior MMA branch was embolized in 19 (14%), posterior in 16 (12%), and both in 102 (74.5%) cases. Penetration of the liquid embolic to the contralateral MMA or into the falx was present in 38 (28%) and 31 (23%) cases, respectively, and 46 (34%) cases had ophthalmic or petrous collateral (n = 41, 30%) branches. MMA branches coiled include the primary trunk (25.5%, n = 35), primary and anterior or posterior MMA trunks (20%, n = 28), or primary with the anterior and posterior trunks (54%, n = 74). A mild ipsilateral facial nerve palsy was reported, which remained stable at discharge and follow-up. Absence of anterograde flow in the MMA occurred in 137 (100%) cases, and no cases required periprocedural rescue surgery for cSDH evacuation. The average follow-up length was 170 ± 17.9 days, cSDH was reduced by 4.24 ± 0.5(mm) and the midline shift by 1.46 ± 0.27(mm). Complete resolution was achieved in 63 (46.0%) cases. Conclusion: Proximal MMA coil embolization is a safe technique for providing additional embolization/occlusion of the MMA in cSDH embolization procedures. Further studies are needed to evaluate the potential added efficacy of this technique.
• Campos, J. K., Meyer, B. M., Zarrin, D. A., Khan, M. W., Collard de Beaufort, J. C., Amin, G., Avery, M. B., Golshani, K., Beaty, N. B., Bender, M. T., Colby, G. P., Lin, L. M., & Coon, A. L. (2024). Immediate procedural safety of adjunctive proximal coil occlusion in middle meningeal artery embolization for chronic subdural hematomas: Experience in 137 cases. Interventional neuroradiology : journal of peritherapeutic neuroradiology, surgical procedures and related neurosciences, 15910199231224003.
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  Endovascular embolization of the middle meningeal artery (MMA) has emerged as an adjunctive and stand-alone modality for the management of chronic subdural hematomas (cSDH). We report our experience utilizing proximal MMA coil embolization to augment cSDH devascularization in MMA embolization.
• Sheldon, B. L., Riordan, K., Fallahi, S., Samargandy, S., Le, C. H., & Avery, M. B. (2024). An unusual case of aggressive endometrial adenocarcinoma metastasis to the clivus: illustrative case. Journal of Neurosurgery: Case Lessons, 8(Issue 18). doi:10.3171/case24392
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  BACKGROUND Though endometrial carcinomas are a relatively common cancer of the female genitourinary tract, they rarely metastasize. Similarly, clival metastases make up a tiny fraction of all brain metastases. To the authors’ knowledge, an endometrial carcinoma clival metastasis has never been described in the literature; therefore, the authors present the following unusual case of a 69-year-old female with a history of an initially grade 2 endometrial adenocarcinoma that metastasized to her clivus. OBSERVATIONS Endometrial carcinoma has the potential to metastasize to the clivus. LESSONS Endometrial carcinoma, even when initially low grade, can metastasize intracranially. Prompt diagnosis with tissue biopsy and radiation is the mainstay of treatment, although the prognosis remains poor.
• Sheldon, B. L., Riordan, K., Fallahi, S., Samargandy, S., Le, C. H., & Avery, M. B. (2024). An unusual case of aggressive endometrial adenocarcinoma metastasis to the clivus: illustrative case. Journal of neurosurgery. Case lessons, 8(18).
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  Though endometrial carcinomas are a relatively common cancer of the female genitourinary tract, they rarely metastasize. Similarly, clival metastases make up a tiny fraction of all brain metastases. To the authors' knowledge, an endometrial carcinoma clival metastasis has never been described in the literature; therefore, the authors present the following unusual case of a 69-year-old female with a history of an initially grade 2 endometrial adenocarcinoma that metastasized to her clivus.
• Mamaril-Davis, J., Aguilar-Salinas, P., Avila, M. J., Dumont, T., & Avery, M. B. (2023). Recurrence Rates Following Treatment of Spinal Vascular Malformations: A Systematic Review and Meta-Analysis. World Neurosurgery, 173(Issue). doi:10.1016/j.wneu.2023.02.040
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  Background: Spinal vascular malformations (SVMs), including arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs), are a varied group of vascular lesions that can be subclassified according to localization, vascular structure, and hemodynamics. Early intervention is necessary to halt progression of disease and minimize irreversible dysfunction. We sought to characterize initial treatment success and recurrence rates following interventional treatment of various types of SVMs. Methods: A systematic review and meta-analysis were performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. SVMs were categorized into 4 groups: dural AVFs, perimedullary AVFs, intramedullary AVMs, and extradural-intradural AVMs (e.g., epidural, paraspinal). Initial occlusion, recurrence, and complication rates were compared using random-effects analysis. Results: There were 112 manuscripts included, with a total of 5626 patients with SVM. For treatment, 2735 patients underwent endovascular embolization, 2854 underwent surgical resection, and 37 underwent stereotactic radiosurgery. The initial treatment success and overall recurrence rates following surgical resection of all SVMs were 89.5% (95% CI: 80.5%–98.5%) and 2.3% (95% CI: 0.9%–3.7%), respectively. Those rates following endovascular embolization were 55.9% (95% CI: 30.3%–81.5%) and 27.7% (95% CI: 11.2%–44.2%), respectively. Higher rates of initial treatment success and lower rates of recurrence with surgery were observed in all subtypes compared to embolization. Overall complication rates were higher after embolization for each of the SVM categories. Conclusions: Surgical resection of SVMs provided higher rates of initial complete occlusion and lower rates of recurrence than endovascular techniques. Attaining technical success through obliteration must still be weighed against clinical impact and natural history of the specific vascular malformation.
• Mamaril-Davis, J., Aguilar-Salinas, P., Avila, M. J., Dumont, T., & Avery, M. B. (2023). Recurrence Rates Following Treatment of Spinal Vascular Malformations: A Systematic Review and Meta-Analysis. World neurosurgery, 173, e250-e297.
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  Spinal vascular malformations (SVMs), including arteriovenous malformations (AVMs) and arteriovenous fistulas (AVFs), are a varied group of vascular lesions that can be subclassified according to localization, vascular structure, and hemodynamics. Early intervention is necessary to halt progression of disease and minimize irreversible dysfunction. We sought to characterize initial treatment success and recurrence rates following interventional treatment of various types of SVMs.
• Avery, M. B., Mallari, R. J., Barkhoudarian, G., & Kelly, D. F. (2022). Supraorbital and mini-pterional keyhole craniotomies for brain tumors: a clinical and anatomical comparison of indications and outcomes in 204 cases. Journal of Neurosurgery, 136(Issue 5). doi:10.3171/2021.6.jns21759
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  OBJECTIVE The authors' objective was to compare the indications, outcomes, and anatomical limits of supraorbital (SO) and mini-pterional (MP) craniotomies in patients with intra- and extraaxial brain tumors, and to assess approach selection, utility of endoscopy, and surgical field overlap. METHODS A retrospective analysis was conducted of all brain tumor patients who underwent an SO or MP approach. The analyzed characteristics included pathology, endoscopy use, extent of resection, length of stay (LOS), and complications. On the basis of preoperative MRI data, tumor heatmaps were constructed to compare surgical access provided by both routes, including coronal projection heatmaps for parasellar tumors. RESULTS From 2007 to 2020, 158 patients underwent 173 (84.8%) SO craniotomies and 30 patients underwent 31 (15.2%) MP craniotomies; 71 (34.8%) procedures were reoperations. Of these 204 operations, 110 (63.6%) SO and 21 (67.7%) MP approaches were for extraaxial tumors (meningiomas in 65% and 76.2%, respectively). Gliomas and metastases together represented 84.1% and 70% of intraaxial tumors accessed with SO and MP approaches, respectively. Overall, 56.1% of tumors accessed with the SO approach and 41.9% of those accessed with the MP approach were in the parasellar region. Axial projection heatmaps showed that SO access extended along the entire ipsilateral and medial contralateral anterior cranial fossa, parasellar region, ipsilateral sylvian fissure, medial middle cranial fossa, and anterior midbrain, whereas MP access was limited to the ipsilateral middle cranial fossa, sylvian fissure, lateral parasellar region, and posterior aspect of anterior cranial fossa. Coronal projection heatmaps showed that parasellar access extended further superiorly with the SO approach compared with that of the MP approach. Endoscopy was utilized in 98 (56.6%) SO craniotomies and 7 (22.6%) MP craniotomies, with further tumor resection in 48 (49%) and 5 (71.4%) cases, respectively. Endoscope-assisted tumor removal was clustered in areas that were generally at farther distances from the craniotomy or in angled locations such as the cribriform plate region where microscopic visualization is limited. Gross-total or near-total resection was achieved in 120/173 (69%) SO approaches and 21/31 (68%) MP approaches. Major complications occurred in 11 (6.4%) SO approaches and 1 (3.2%) MP approach (p = 0.49). The median LOS decreased to 2 days in the last 2 years of the study. CONCLUSIONS This clinical experience suggests the SO and MP craniotomies are versatile, safe, and complementary approaches for tumors located in the anterior and middle cranial fossae and perisylvian and parasellar regions. The SO route, used in 85% of cases, achieved greater overall reach than the MP route. Both approaches may benefit from expanded visualization with endoscopy.
• Olson, M. G., Avery, M. B., Javaherian, S., Sivakumar, W., Kelly, D. F., Griffiths, C., & Barkhoudarian, G. (2022). Minimally invasive pericranial flap harvest through a supraorbital eyebrow craniotomy: Technical note in salvage skull base reconstruction. Clinical Neurology and Neurosurgery, 217(Issue). doi:10.1016/j.clineuro.2022.107266
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  Background and importance: The supraorbital eyebrow craniotomy is a minimally invasive approach that provides access to pathologies of the anterior and middle cranial fossae. Vascularized flaps are preferred when considering reconstructive options, however, small incisions may not provide adequate access to vascularized tissue. We present two cases demonstrating a modified technique for harvesting pericranium through an eyebrow supraorbital craniotomy for reconstruction of large skull base defects. Clinical presentation: The first case is of a 62-year-old woman with an invasive esthesioneuroblastoma. Multiple resections and reconstructions, including a large frontal craniectomy and titanium mesh cranioplasty, resulted in refractory tension pneumocephalus. A supraorbital craniotomy was performed with endoscope-assisted harvesting of a pericranial flap through a coronal plane stab incision for definitive repair. The second case is a 44-year-old woman with a high-grade neuroendocrine tumor transgressing the anterior cranial fossa. Resection was achieved via combined supraorbital eyebrow craniotomy and endoscopic endonasal approach. A multilayered reconstruction including a pericranial flap from above and a nasoseptal flap from below was used to reconstruct the defect. The pericranial flap was again harvested with endoscope assistance through a coronal plane stab incision. Both cases had excellent outcomes with no post-operative cerebrospinal fluid leak. Conclusion: Repair of large anterior cranial fossa defects with a vascularized pericranial flap can be performed through a supraorbital eyebrow craniotomy. Utilizing small, strategically placed transverse (coronal plane) incisions behind the hairline allows for the endoscope-assisted harvesting of a highly customized flap. This modified technique increases the flexibility of the minimally invasive supraorbital craniotomy.
• Olson, M. G., Avery, M. B., Javaherian, S., Sivakumar, W., Kelly, D. F., Griffiths, C., & Barkhoudarian, G. (2022). Minimally invasive pericranial flap harvest through a supraorbital eyebrow craniotomy: Technical note in salvage skull base reconstruction. Clinical neurology and neurosurgery, 217, 107266.
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  The supraorbital eyebrow craniotomy is a minimally invasive approach that provides access to pathologies of the anterior and middle cranial fossae. Vascularized flaps are preferred when considering reconstructive options, however, small incisions may not provide adequate access to vascularized tissue. We present two cases demonstrating a modified technique for harvesting pericranium through an eyebrow supraorbital craniotomy for reconstruction of large skull base defects.
• Al Saiegh, F., Sweid, A., Chalouhi, N., Philipp, L., Mouchtouris, N., Khanna, O., Avery, M. B., Schmidt, R. F., Ghosh, R., Hafazalla, K., Weinberg, J. H., Starke, R. M., Gooch, M. R., Tjoumakaris, S., Rosenwasser, R. H., & Jabbour, P. (2021). Comparison of Transradial vs Transfemoral Access in Neurovascular Fellowship Training: Overcoming the Learning Curve. Operative neurosurgery (Hagerstown, Md.), 21(1), E3-E7.
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  The transradial access (TRA) is rapidly gaining popularity for neuroendovascular procedures as there is strong evidence for its benefits compared to the traditional transfemoral access (TFA). However, the transition to TRA bears some challenges including optimization of the interventional suite set-up and workflow as well as its impact on fellowship training.
• Avery, M. B., Mallari, R. J., Barkhoudarian, G., & Kelly, D. F. (2021). Supraorbital and mini-pterional keyhole craniotomies for brain tumors: a clinical and anatomical comparison of indications and outcomes in 204 cases. Journal of neurosurgery, 1-11.
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  The authors' objective was to compare the indications, outcomes, and anatomical limits of supraorbital (SO) and mini-pterional (MP) craniotomies in patients with intra- and extraaxial brain tumors, and to assess approach selection, utility of endoscopy, and surgical field overlap.
• Belanger, B. L., Avery, M. B., Sen, A., Eesa, M., & Mitha, A. P. (2021). Creating Clinically Relevant Aneurysm Sizes in the Rabbit Surgical Elastase Model. World Neurosurgery, 152(Issue). doi:10.1016/j.wneu.2021.05.069
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  Background: Creating aneurysm sizes in animal models that resemble human aneurysms is essential to study and test neuroendovascular devices. The commonly used rabbit surgical elastase model, however, produces saccular aneurysms that are smaller than those typically treated in humans. The goal of this study was to determine whether an increased vessel stump length and the addition of calcium chloride to the incubation solution has an effect on the resulting aneurysm size. Methods: Using a modified aneurysm creation method, 32 female New Zealand White rabbits underwent aneurysm creation procedures. Subjects were equally allocated into 4 different groups based on vessel stump length (2 cm controls vs. 3 cm) and incubation solution (elastase alone controls vs. a 1:1 mixture of elastase and calcium chloride). At 4 weeks, all animals underwent angiography to determine the resulting aneurysm size by a neurointerventionalist who was blinded to treatment group. Results: An increase in stump length from 2 cm to 3 cm resulted in a significant increase in the height of aneurysm (P < 0.05). Compared with control animals, the combination of a 3-cm stump length and the addition of calcium chloride to the incubation solution resulted in a significant increase in aneurysm height, width, and volume (P < 0.05). Conclusions: Creating larger aneurysms is necessary for the rabbit model to be more clinically relevant. Our study demonstrated that the utilization of a 3-cm vessel stump as well as both calcium chloride and elastase in the incubation solution results in aneurysm sizes that more closely resemble the population of aneurysms treated in humans.
• Belanger, B. L., Avery, M. B., Sen, A., Eesa, M., & Mitha, A. P. (2021). Creating Clinically Relevant Aneurysm Sizes in the Rabbit Surgical Elastase Model. World neurosurgery, 152, e173-e179.
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  Creating aneurysm sizes in animal models that resemble human aneurysms is essential to study and test neuroendovascular devices. The commonly used rabbit surgical elastase model, however, produces saccular aneurysms that are smaller than those typically treated in humans. The goal of this study was to determine whether an increased vessel stump length and the addition of calcium chloride to the incubation solution has an effect on the resulting aneurysm size.
• Chalouhi, N., Sweid, A., Al Saiegh, F., Sajja, K. C., Schmidt, R. F., Avery, M. B., Mouchtouris, N., Khanna, O., Weinberg, J. H., Romo, V., Tjoumakaris, S., Gooch, M. R., Herial, N., Rosenwasser, R. H., & Jabbour, P. (2021). Feasibility and initial experience of left radial approach for diagnostic neuroangiography. Scientific reports, 11(1), 1089.
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  Neuroangiography has seen a recent shift from transfemoral to transradial access. In transradial neuroangiography, the right dominant hand is the main access used. However, the left side may be used specifically for left posterior circulation pathologies and when right access cannot be used. This study describes our initial experience with left radial access for diagnostic neuroangiography and assesses the feasibility and safety of this technique. We performed a retrospective review of a prospective database of consecutive patients between April 2018 and January 2020, and identified 20 patients whom a left radial access was used for neurovascular procedures. Left transradial neuroangiography was successful in all 20 patients and provided the sought diagnostic information; no patient required conversion to right radial or femoral access. Pathology consisted of anterior circulation aneurysms in 17 patients (85%), brain tumor in 1 patient (5%), and intracranial atherosclerosis disease involving the middle cerebral artery in 2 patients (10%). The left radial artery was accessed at the anatomic snuffbox in 18 patients (90%) and the wrist in 2 patients (10%). A single vessel was accessed in 7 (35%), two vessels in 8 (40%), three vessels in 4 (20%), and four vessels in 1 (5%). Catheterization was successful in 71% of the cases for the right internal carotid artery and in only 7.7% for the left internal carotid artery. There were no instances of radial artery spasm, radial artery occlusion, or procedural complications. Our initial experience found the left transradial access to be a potentially feasible approach for diagnostic neuroangiography even beyond the left vertebral artery. The approach is strongly favored by patients but has significant limitations compared with the right-sided approach.
• Mallari, R. J., Avery, M. B., Corlin, A., Eisenberg, A., Hammond, T. C., Martin, N. A., Barkhoudarian, G., & Kelly, D. F. (2021). Streamlining brain tumor surgery care during the COVID-19 pandemic: A case-control study. PloS one, 16(7), e0254958.
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  The COVID-19 pandemic forced a reconsideration of surgical patient management in the setting of scarce resources and risk of viral transmission. Herein we assess the impact of implementing a protocol of more rigorous patient education, recovery room assessment for non-ICU admission, earlier mobilization and post-discharge communication for patients undergoing brain tumor surgery.
• Schmidt, R. F., Sweid, A., Chalouhi, N., Avery, M. B., Sajja, K. C., Al-Saiegh, F., Weinberg, J. H., Asada, A., Joffe, D., Zarzour, H. K., Gooch, M. R., Rosenwasser, R. H., Jabbour, P. M., & Tjoumakaris, S. I. (2021). Endovascular Management of Complex Fenestration-Associated Aneurysms: A Single-Institution Retrospective Study and Review of Existing Techniques. World neurosurgery, 146, e607-e617.
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  Aneurysms associated with fenestrations of intracranial arteries are exceptionally rare findings. Management strategies for these aneurysms are not well-defined, especially regarding endovascular treatment. We sought to investigate the strategies and feasibility of endovascular treatment approaches for various fenestration-associated intracranial aneurysms.
• Al Saiegh, F., Ghosh, R., Leibold, A., Avery, M. B., Schmidt, R. F., Theofanis, T., Mouchtouris, N., Philipp, L., Peiper, S. C., Wang, Z. X., Rincon, F., Tjoumakaris, S. I., Jabbour, P., Rosenwasser, R. H., & Gooch, M. R. (2020). Status of SARS-CoV-2 in cerebrospinal fluid of patients with COVID-19 and stroke. Journal of neurology, neurosurgery, and psychiatry, 91(8), 846-848.
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  Emergence of the novel corona virus (severe acute respiratory syndrome (SARS)-CoV-2) in December 2019 has led to the COVID-19 pandemic. The extent of COVID-19 involvement in the central nervous system is not well established, and the presence or the absence of SARS-CoV-2 particles in the cerebrospinal fluid (CSF) is a topic of debate.
• Jamshidi, M., Rajabian, M., Avery, M. B., Sundararaj, U., Ronsky, J., Belanger, B., Wong, J. H., & Mitha, A. P. (2020). A novel self-expanding primarily bioabsorbable braided flow-diverting stent for aneurysms: Initial safety results. Journal of NeuroInterventional Surgery, 12(Issue 7). doi:10.1136/neurintsurg-2019-015555
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  Introduction The advent of metal flow-diverting stents has provided neurointerventionalists with an option for treating aneurysms without requiring manipulations within the aneurysm sac. The large amount of metal in these stents, however, can lead to early and late thrombotic complications, and thus requires long-term antiplatelet agents. Bioabsorbable stents have been postulated to mitigate the risk of these complications. Here we present early data on the first self-expandable primarily bioabsorbable stent for aneurysms. Methods Braided stents were developed using poly-L-lactic acid fibers with material surface area similar to metal flow diverters. Crush resistance force, hemolysis, and thrombogenicity were determined and compared with existing commercial devices. Stents were deployed in infra-renal rabbit aortas to determine angiographic side branch patency and to study neointima formation for a 1-month follow-up period. Results Crush resistance force was determined to be on the order of existing commercial devices. Hemolytic behavior was similar to existing metal devices, and thrombogenicity was lower than metal flow-diverting stents. A smooth neointimal layer was found over the absorbable stent surface and all covered side branches were patent at follow-up. Conclusion The design of self-expanding primarily bioabsorbable flow-diverting stents is possible, and preliminary safety data is consistent with a favorable profile in terms of mechanical behavior, hemocompatibility, side branch patency, and histological effects. Additional in vitro and long-term in vivo studies are in progress and will help determine aneurysm occlusion rates and absorption characteristics of the stent.
• Jamshidi, M., Rajabian, M., Avery, M. B., Sundararaj, U., Ronsky, J., Belanger, B., Wong, J. H., & Mitha, A. P. (2020). A novel self-expanding primarily bioabsorbable braided flow-diverting stent for aneurysms: initial safety results. Journal of neurointerventional surgery, 12(7), 700-705.
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  The advent of metal flow-diverting stents has provided neurointerventionalists with an option for treating aneurysms without requiring manipulations within the aneurysm sac. The large amount of metal in these stents, however, can lead to early and late thrombotic complications, and thus requires long-term antiplatelet agents. Bioabsorbable stents have been postulated to mitigate the risk of these complications. Here we present early data on the first self-expandable primarily bioabsorbable stent for aneurysms.
• Khanna, O., Velagapudi, L., Das, S., Sweid, A., Mouchtouris, N., Al Saiegh, F., Avery, M. B., Chalouhi, N., Schmidt, R. F., Sajja, K., Gooch, M. R., Tjoumakaris, S., Rosenwasser, R. H., & Jabbour, P. M. (2020). A comparison of radial versus femoral artery access for acute stroke interventions. Journal of neurosurgery, 1-6.
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  In this study, the authors aimed to investigate procedural and clinical outcomes between radial and femoral artery access in patients undergoing thrombectomy for acute stroke.
• Sajja, K. C., Sweid, A., Al Saiegh, F., Chalouhi, N., Avery, M. B., Schmidt, R. F., Tjoumakaris, S. I., Gooch, M. R., Herial, N., Abbas, R., Zarzour, H., Romo, V., Rosenwasser, R., & Jabbour, P. (2020). Endovascular robotic: feasibility and proof of principle for diagnostic cerebral angiography and carotid artery stenting. Journal of neurointerventional surgery, 12(4), 345-349.
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  Robots in surgery aid in performing delicate, precise maneuvers that humans, with inherent physical abilities, may be limited to perform. The CorPath 200 system is FDA approved and is being implemented in the US for interventional cardiology procedures. CorPath GRX robotic-assisted platform is the next-generation successor of CorPath 200.
• Avery, M. B., Belanger, B. L., Bromley, A., Sen, A., & Mitha, A. P. (2019). Mesenchymal Stem Cells Exhibit Both a Proinflammatory and Anti-Inflammatory Effect on Saccular Aneurysm Formation in a Rabbit Model. Stem Cells International, 2019(Issue). doi:10.1155/2019/3618217
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  Several studies have demonstrated a potential interaction between mesenchymal stem cells (MSCs) and saccular aneurysms. In this study, we sought to determine whether allogenic bone marrow-derived MSCs had the ability to prevent aneurysm formation in a known rabbit elastase aneurysm model. MSCs were injected intravenously in experimental rabbits at the time of surgical creation and two weeks postcreation and compared with control rabbits receiving vehicle injection. Angiography was used to compare aneurysm measurements four weeks postcreation, and aneurysms were harvested for histological properties. Serum was collected longitudinally to evaluate cytokine alterations. Serum from control animals was also utilized to perform in vitro tests with MSCs to compare the effect of the serologic environment in animals with and without aneurysms on MSC proliferation and cytokine production. While aneurysm morphometric comparisons revealed no differences, significant cytokine alterations were observed in vitro and in vivo, suggesting both anti-inflammatory and proinflammatory processes were occurring in the presence of MSCs. Histological analyses suggested that tunica intima hyperplasia was inhibited in the presence of MSCs.
• Avery, M. B., Belanger, B. L., Bromley, A., Sen, A., & Mitha, A. P. (2019). Mesenchymal Stem Cells Exhibit Both a Proinflammatory and Anti-Inflammatory Effect on Saccular Aneurysm Formation in a Rabbit Model. Stem cells international, 2019, 3618217.
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  Several studies have demonstrated a potential interaction between mesenchymal stem cells (MSCs) and saccular aneurysms. In this study, we sought to determine whether allogenic bone marrow-derived MSCs had the ability to prevent aneurysm formation in a known rabbit elastase aneurysm model. MSCs were injected intravenously in experimental rabbits at the time of surgical creation and two weeks postcreation and compared with control rabbits receiving vehicle injection. Angiography was used to compare aneurysm measurements four weeks postcreation, and aneurysms were harvested for histological properties. Serum was collected longitudinally to evaluate cytokine alterations. Serum from control animals was also utilized to perform tests with MSCs to compare the effect of the serologic environment in animals with and without aneurysms on MSC proliferation and cytokine production. While aneurysm morphometric comparisons revealed no differences, significant cytokine alterations were observed and , suggesting both anti-inflammatory and proinflammatory processes were occurring in the presence of MSCs. Histological analyses suggested that tunica intima hyperplasia was inhibited in the presence of MSCs.
• Avery, M. B., Magal, I., Kherani, A., & Mitha, A. P. (2019). Risk of Stroke in Patients With Ocular Arterial Occlusive Disorders: A Retrospective Canadian Study. Journal of the American Heart Association, 8(3), e010509.
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  Background Monocular vision loss, attributed to either central retinal artery occlusion ( CRAO ), branch retinal artery occlusion ( BRAO ), or ocular ischemic syndrome ( OIS ), is thought to be associated with an increased prevalence of cerebral infarcts. However, there is a paucity of data substantiating this. We aimed to investigate this relationship in a Canadian center and further understand the importance of associated internal carotid artery stenosis in potential clinical decision making. Methods and Results We performed a retrospective cohort study at a comprehensive stroke center of patients presenting initially with CRAO , BRAO , or OIS to a centralized ophthalmology center over a 5-year period. Patients were followed for 3 years for the occurrence of a hemispheric stroke. We identified 83 affected eyes, with 31 CRAO , 35 BRAO , and 17 OIS patients. Before ocular diagnosis, 32.3%, 11.4%, and 41.2% of CRAO , BRAO , and OIS patients, respectively, experienced a symptomatic stroke. Of the remaining patients, 4.8%, 12.9%, and 40%, respectively, suffered a hemispheric stroke within 3 years of ocular diagnosis. Logistic regressions suggested that for CRAO and BRAO patients together, the degree of ipsilateral internal carotid artery stenosis is unable to predict the occurrence of a stroke ( P=0.18), whereas our model correctly predicted a stroke in 82.4% of OIS patients ( P=0.005). Conclusions CRAO , BRAO , and OIS are associated with significantly increased symptomatic stroke rates. Degree of ipsilateral internal carotid artery stenosis may not be useful in risk stratification for these patients, suggesting that they should be triaged appropriately for stroke risk-factor management, independent of internal carotid artery stenosis.
• Avery, M. B., Magal, I., Kherani, A., & Mitha, A. P. (2019). Risk of stroke in patients with ocular arterial occlusive disorders: A retrospective Canadian study. Journal of the American Heart Association, 8(Issue 3). doi:10.1161/jaha.118.010509
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  Background-—Monocular vision loss, attributed to either central retinal artery occlusion (CRAO), branch retinal artery occlusion (BRAO), or ocular ischemic syndrome (OIS), is thought to be associated with an increased prevalence of cerebral infarcts. However, there is a paucity of data substantiating this. We aimed to investigate this relationship in a Canadian center and further understand the importance of associated internal carotid artery stenosis in potential clinical decision making. Methods and Results-—We performed a retrospective cohort study at a comprehensive stroke center of patients presenting initially with CRAO, BRAO, or OIS to a centralized ophthalmology center over a 5-year period. Patients were followed for 3 years for the occurrence of a hemispheric stroke. We identified 83 affected eyes, with 31 CRAO, 35 BRAO, and 17 OIS patients. Before ocular diagnosis, 32.3%, 11.4%, and 41.2% of CRAO, BRAO, and OIS patients, respectively, experienced a symptomatic stroke. Of the remaining patients, 4.8%, 12.9%, and 40%, respectively, suffered a hemispheric stroke within 3 years of ocular diagnosis. Logistic regressions suggested that for CRAO and BRAO patients together, the degree of ipsilateral internal carotid artery stenosis is unable to predict the occurrence of a stroke (P=0.18), whereas our model correctly predicted a stroke in 82.4% of OIS patients (P=0.005). Conclusions-—CRAO, BRAO, and OIS are associated with significantly increased symptomatic stroke rates. Degree of ipsilateral internal carotid artery stenosis may not be useful in risk stratification for these patients, suggesting that they should be triaged appropriately for stroke risk-factor management, independent of internal carotid artery stenosis.
• De Lotbinière-Bassett, M., Avery, M. B., & Starreveld, Y. P. (2019). A Unique Case of Sinonasal Teratocarcinosarcoma Presenting as Foster Kennedy Syndrome. Canadian Journal of Neurological Sciences, 46(Issue 3). doi:10.1017/cjn.2019.33
• de Lotbinière-Bassett, M., Avery, M. B., & Starreveld, Y. P. (2019). A Unique Case of Sinonasal Teratocarcinosarcoma Presenting as Foster Kennedy Syndrome. The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques, 46(3), 366-368.
• Avery, M. B., Sambrano, S., Khader Eliyas, J., Eesa, M., & Mitha, A. P. (2018). Accuracy and precision of venous pressure measurements of endovascular microcatheters in the setting of dural venous sinus stenosis. Journal of NeuroInterventional Surgery, 10(Issue 4). doi:10.1136/neurintsurg-2017-013155
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  Introduction Dural venous sinus stenosis (DVSS) may lead to increased intracranial pressure, sometimes requiring a stent if a high pressure gradient exists. Many neuroendovascular physicians use microcatheters to measure gradients, yet there are no studies comparing the accuracies and precisions of modern day microcatheters. We examined pressure recordings from five commonly used microcatheters in an experimental DVSS model. Methods Using a programmable pump, dynamic flow was established in a closed circuit mimicking the venous sinus waveform. Microcatheters with 150 cm effective lengths were connected proximally to pressure transducers. Mean recording pressures were compared with a high fidelity microcatheter (HFM) in several configurations including no stenosis, proximal to a focal stenosis, and distal to a focal stenosis in opposing orientations. Results All microcatheters recorded lower pressures than the HFM. Three of the five microcatheters successfully met intracranial pressure monitoring device standards in all conditions, while one did not meet standards in any configuration. The performance of the final microcatheter was variable, with inaccuracies occurring in unrestricted flow. All microcatheters demonstrated relatively high precision, but with variable accuracies. The larger diameter microcatheters displayed the least damping and therefore the greatest accuracies. Of the three smaller microcatheters, dimensions did not predict performance, suggesting that microcatheter construction may also play a role in pressure accuracy. Conclusion The use of microcatheters to record dural venous sinus pressures must be done with an understanding of the inherent limitations and inaccuracies, especially if clinical decisions are made from the results.
• Avery, M. B., Sambrano, S., Khader Eliyas, J., Eesa, M., & Mitha, A. P. (2018). Accuracy and precision of venous pressure measurements of endovascular microcatheters in the setting of dural venous sinus stenosis. Journal of neurointerventional surgery, 10(4), 387-391.
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  Dural venous sinus stenosis (DVSS) may lead to increased intracranial pressure, sometimes requiring a stent if a high pressure gradient exists. Many neuroendovascular physicians use microcatheters to measure gradients, yet there are no studies comparing the accuracies and precisions of modern day microcatheters. We examined pressure recordings from five commonly used microcatheters in an experimental DVSS model.
• Avery, M., Alaqeel, A., Bromley, A., Chen, Y., Wong, J., Eesa, M., & Mitha, A. (2018). A refined experimental model of fusiform aneurysms in a rabbit carotid artery. Journal of Neurosurgery, 131(1). doi:10.3171/2018.2.JNS173168
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  Objective: Reliable animal models are an important aspect of translational research, especially for relatively uncommon clinical entities such as fusiform aneurysms. While several animal models exist, very few are tailored to cerebral fusiform aneurysms, which have unique attributes compared to abdominal fusiform aneurysms. The authors aimed to build from previous models to create a cerebral fusiform aneurysm model that is simple to use and reliable. Methods: Twelve female New Zealand White rabbits were assigned to 3 groups: group E, elastase only; group C, CaCl2 only; group EC, elastase + CaCl2. All rabbits underwent surgical exposure of the right common carotid artery (CCA) and 20 minutes of peri-carotid incubation with their respective chemicals. Angiography was performed 6 weeks later for arterial dilation measurements, with 50% increase in diameter being defined as fusiform aneurysm formation. The arterial segments, along with the contralateral CCAs, were harvested and assessed histologically for wall component measurements and elastin semiquantification. A separate rabbit underwent aneurysm creation per the group EC protocol and was treated with an endovascular flow-diversion device. Results: All of the group EC rabbits developed fusiform aneurysms (mean dilation of 88%), while none of the group E or group C rabbits developed aneurysms (p = 0.001). Histological analysis revealed increased internal elastic lamina fragmentation in the group EC aneurysms, which also had less tunica intima hyperplasia. All aneurysms exhibited thinning of the tunica media and reduction in elastin content. The use of an endovascular flow-diverting stent was successful, with complete parent vessel remodeling, as expected, 4 weeks after deployment. Conclusions: The peri-arterial application of combined elastase and CaCl2 to the CCA appears sufficient to reliably produce fusiform aneurysms after 6 weeks. Exposure to elastase or CaCl2 individually appears insufficient, despite the observed histological changes to the arterial wall. The proposed fusiform aneurysm model is able to accommodate endovascular devices, simulating the tortuous pathway experienced in using such devices in human cerebral aneurysms and thus is a satisfactory model to use in translational research.
• Ryu, W. H., Avery, M. B., Dharampal, N., Allen, I. E., & Hetts, S. W. (2017). Utility of perfusion imaging in acute stroke treatment: a systematic review and meta-analysis. Journal of neurointerventional surgery, 9(10), 1012-1016.
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  Variability in imaging protocols and techniques has resulted in a lack of consensus regarding the incorporation of perfusion imaging into stroke triage and treatment. The objective of our study was to evaluate the available scientific evidence regarding the utility of perfusion imaging in determining treatment eligibility in patients with acute stroke and in predicting their clinical outcome.
• Avery, M., Chehab, S., Wong, J., & Mitha, A. (2016). Intraoperative indocyanine green videoangiography to guide decision making regarding need for vessel bypass: A case report and technical note. Surgical Neurology International, 7(Issue). doi:10.4103/2152-7806.173567
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  Background: Indocyanine green (ICG) videoangiography is an intraoperative technique recently used in vascular neurosurgery to assess the presence or absence of blood flow during critical times of a procedure. These include, but are not limited to, detecting whether daughter branches or perforators are patent after placing a vascular clip or determining whether an aneurysm has been completely isolated from the cerebral circulation after clipping. We present a case of a less-commonly reported application of ICG videoangiography involving the selection of a vessel to act as the bypass recipient once the need is identified during the surgical treatment of a complex intracranial aneurysm. Case Description: A 51-year-old male presented with a ruptured dissecting superior cerebellar artery (SCA) aneurysm that had two branches arising from the dome. Due to the difficult morphology of this aneurysm, a superficial temporal artery to SCA bypass was planned. We used ICG videoangiography to identify the branch that had insufficient retrograde flow via collateral circulation, to which the bypass was performed, followed by the isolation of the aneurysm from the cerebral circulation using permanent surgical clips. Conclusion: Our case represents a possible use of ICG videoangiography during the operative treatment of a difficult aneurysm. Our patient suffered no infarcts postoperatively. In the correct clinical context, this method represents a possible treatment option for complex aneurysms requiring a bypass.
• Ogilvy, C. S., Chua, M. H., Fusco, M. R., Griessenauer, C. J., Harrigan, M. R., Sonig, A., Siddiqui, A. H., Levy, E. I., Snyder, K., Avery, M., Mitha, A., Shores, J., Hoh, B. L., & Thomas, A. J. (2015). Validation of a System to Predict Recanalization After Endovascular Treatment of Intracranial Aneurysms. Neurosurgery, 77(2), 168-73; discussion 173-4.
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  With increasing use of endovascular techniques in the treatment of ruptured and unruptured aneurysms, the issue of obliteration efficacy has become increasingly important. We have previously reported the Aneurysm Recanalization Stratification Scale, which uses accessible predictors including aneurysm-specific factors (size, rupture, and intraluminal thrombosis) and treatment-related features (treatment modality and immediate angiographic result) to predict retreatment risk after endovascular therapy.
• Ogilvy, C. S., Chua, M. H., Fusco, M. R., Griessenauer, C. J., Harrigan, M. R., Sonig, A., Siddiqui, A. H., Levy, E. I., Snyder, K., Avery, M., Mitha, A., Shores, J., Hoh, B. L., & Thomas, A. J. (2015). Validation of a System to Predict Recanalization after Endovascular Treatment of Intracranial Aneurysms. Neurosurgery, 77(Issue 2). doi:10.1227/neu.0000000000000744
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  BACKGROUND: With increasing use of endovascular techniques in the treatment of ruptured and unruptured aneurysms, the issue of obliteration efficacy has become increasingly important. We have previously reported the Aneurysm Recanalization Stratification Scale, which uses accessible predictors including aneurysm-specific factors (size, rupture, and intraluminal thrombosis) and treatment-related features (treatment modality and immediate angiographic result) to predict retreatment risk after endovascular therapy. OBJECTIVE: To assess the external validity of the Aneurysm Recanalization Stratification Scale. METHODS: External validity was assessed in independent cohorts from 4 centers in the United States and Canada where endovascular and open neurovascular procedures are performed, and in a multicenter cohort of 1543 patients. Probability of retreatment stratified by risk score was derived for each center and the combined multicenter cohort. RESULTS: Despite moderate variability in retreatment rate among centers (29.5%, 9.9%, 9.6%, 26.3%, 19.7%, and 18.3%), the Aneurysm Recanalization Stratification Scale demonstrated good predictive value with C-statistics of 0.799, 0.943, 0.780, 0.695, 0.755, and 0.719 for each center and the combined cohort, respectively. Probability of retreatment stratified by risk score for the combined cohort is as follows: -2, 4.9%; -1, 5.7%; 0, 5.8%; 1, 13.1%; 2, 19.2%; 3, 34.9%; 4, 32.7%; 5, 73.2%; 6, 89.5%; and 7, 100.0%. CONCLUSION: Surgical decision-making and patient-centered informed consent require comprehensive and accessible information on treatment efficacy. The Aneurysm Recanalization Stratification Scale is a valid prognostic index. This is the first comprehensive model that has been developed to quantitatively predict retreatment risk following endovascular therapy.
• Haji, F., Van Adel, B., Avery, M., Megyesi, J., & Young, G. B. (2014). Intracranial aneurysm rupture following intravenous thrombolysis for stroke. Canadian Journal of Neurological Sciences, 41(Issue 1). doi:10.1017/s0317167100016358
• Haji, F., van Adel, B., Avery, M., Megyesi, J., & Young, G. B. (2014). Intracranial aneurysm rupture following intravenous thrombolysis for stroke. The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques, 41(1), 95-8.
• Ranger, A. M., Chaudhary, N., Avery, M., & Lownie, S. (2013). Brainstem cavernoma hemorrhage during pregnancy in a 15-year-old: Description of a unique neurosurgical approach. Journal of Child Neurology, 28(Issue 10). doi:10.1177/0883073812457459
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  Cavernous haemangiomas, or cavernous malformations, have been reported during pregnancy, most of which have been either supratentorial or spinal lesions. We encountered a 15-year old pregnant patient with a rapidly progressive and haemorrhagic brainstem cavernous haemangioma. The case presented here describes the history and findings of this patient, as well as the less-commonly utilized technique we used to access the floor of the fourth ventricle via occipital craniotomy for complete macroscopic resection of this lesion, resulting in the gradual return of most of her neurological deficits. © The Author(s) 2012.
• Ranger, A. M., Chaudhary, N., Avery, M., & Lownie, S. (2013). Brainstem cavernoma hemorrhage during pregnancy in a 15-year-old: description of a unique neurosurgical approach. Journal of child neurology, 28(10), 1312-5.
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  Cavernous haemangiomas, or cavernous malformations, have been reported during pregnancy, most of which have been either supratentorial or spinal lesions. We encountered a 15-year old pregnant patient with a rapidly progressive and haemorrhagic brainstem cavernous haemangioma. The case presented here describes the history and findings of this patient, as well as the less-commonly utilized technique we used to access the floor of the fourth ventricle via occipital craniotomy for complete macroscopic resection of this lesion, resulting in the gradual return of most of her neurological deficits.
• Ranger, A. M., Chaudhary, N., Avery, M., & Fraser, D. (2012). Central pontine and extrapontine myelinolysis in children: a review of 76 patients. Journal of child neurology, 27(8), 1027-37.
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  This study aimed to identify the causes and contributing factors, neurologic presentation, and outcomes of central pontine and extrapontine myelinolysis and to examine any trends in the presentation and course of these disorders over the past 50 years. Seventy-six pediatric cases were identified in the literature. Age, sex, decade of diagnosis, neurologic presentation, outcome, and attributed causes were extracted. The results showed that the diagnosis, course, and outcomes of central pontine and extrapontine myelinolysis clearly have changed over the past few decades. Early cases generally were diagnosed at autopsy as opposed to computed tomography or magnetic resonance imaging more recently. Ninety-four percent of cases prior to 1990 and only 7% of cases from 1990 onward resulted in patient mortality. The decade in which the case was reported was the strongest predictor of outcome (P < .001), followed by sodium dysregulation (P = .045) and dehydration (P = .07).
• Avery, M. (2011). Cavernous hemangioma presenting during pregnancy: a detailed literature review. J Pediatr Neurol.

Presentations

• Avery, M. (2024, June). Dural Arteriovenous Fistulas. University of Arizona Neurosurgery Didactic Conference.
• Avery, M. (2024, November). ENT & Neurosurgery: Better Together. University of Arizona Otolaryngology Grand Rounds.
• Avery, M. (2024, November). Pituitary Surgery. University of Arizona Endocrinology Grand Rounds.
• Avery, M. (2024, October). Pituitary Tumors. Mt Graham Regional Medical Center Grand Rounds.
• Avery, M. (2024, September). A Career in Neurosurgery. University of Arizona Medical Directive Society.
• Avery, M. (2023, April). A Career in Neurosurgery. University of Arizona Alpha Epsilon Delta Society.
• Avery, M. (2023, April). Pituitary Tumors from a Neurosurgical Perspective. University of Arizona Endocrinology Grand Rounds.
• Avery, M. (2023, August). Pterional and Supraorbital Approaches. University of Arizona Neurosurgery Didactic Conference.
• Avery, M. (2023, February). Pituitary Tumors. University of Arizona Neurosurgery Didactic Conference.
• Avery, M. (2023, March). Cerebellopontine Angle and Posterior Fossa. University of Arizona Neurosurgery Didactic Conference.
• Aguilar, P., Mamaril-Davis, J., & Avery, M. (2022, October). Recurrence Rates Following Interventional Treatment of Spinal Cord Arteriovenous Malformations: a Meta-Analysis. Arizona Neurosurgical Society Annual Meeting.
• Avery, M. (2022). Cerebral Aneurysms                     . University of Arizona Neuroscience Grand Rounds.
• Avery, M. (2022). Mesenchymal Stem Cell Therapy for Cerebral Aneurysms. University of Arizona Neuroscience Grand Rounds.
• Avery, M. (2022, April). Pituitary Gland. University of Arizona Neurosurgery Didactic Conference.
• Avery, M. (2022, August). Pterional and Supraorbital Approaches. University of Arizona Neurosurgery Didactic Conference.
• Avery, M. (2021). Invited Lecture at The 11th Annual Neuroscience Nursing Symposium. Pacific Neuroscience Institute.

Poster Presentations

• Samargandy, S., Avery, M., Le, C., & Chang, E. (2023, September). Comparing Physcial and Virtual "Digital Twin" Models of Endoscopic Skull Base Disorders for Pre-Operative Planning. American Rhinologic Society Annual Meeting.
• Mamaril-Davis, J., Aguilar, P., Avila, M., Dumont, T., & Avery, M. (2022, October). Recurrence Rates Following Interventional Treatment of Spinal Cord Arteriovenous Malformations: a Meta-Analysis. Congress of Neurological Surgeons Annual Meeting.
• Avery, M., & Mitha, A. P. (2018, January). Mesenchymal Stem Cells Localize to Developint Saccular Aneurysms. AANS/CNS Cerebrovascular Section Annual Meeting.
• Avery, M., & Mitha, A. P. (2017, July). Can Mesenchymal Stem Cells Inhibit Saccular Aneurysm Formation?. Society of NeuroInterventional Surgery Annual Meeting.
• Avery, M., & Mitha, A. P. (2017, September). Ocular Ischemia is a Significant Risk Ractor for Stroke. Canadian Stroke Congress.