About

Michael Avery, MD, MSc, FRCSC, is an Associate Clinical Professor of Neurosurgery at the College of Medicine - Tucson. He specializes in vascular/endovascular neurosurgery and tumors of the brain, pituitary gland, and skull base. Dr. Avery employs state-of-the-art, minimally invasive techniques whenever possible, including 'keyhole' approaches that result in smaller incisions and shorter hospital stays. He also utilizes endoscopes to treat skull base conditions through the nasal cavity, avoiding external incisions. For neurovascular conditions such as aneurysms and arteriovenous malformations, he often uses minimally invasive endovascular techniques that eliminate the need for incisions, thereby improving cosmetic outcomes and reducing recovery times. Dr. Avery's research interests include stroke and aneurysm treatment outcomes, optimizing perioperative outcomes for skull base tumor surgery, and improving endoscopic techniques.

Research topics

• Medicine
• Surgery
• Internal medicine
• Pathology
• Radiology

Selected publications

• Graded CSF Leak Repair in Endoscopic Endonasal Base Surgeries: Retrospective Analysis of a Single Surgeon's Experience with Simple and Extended Approaches to the Skull Base

  Journal of Neurological Surgery Part B Skull Base · 2026-02-27

  articleSenior author
  PublisherDOI

• Incorporating <scp>HTA</scp> and <scp>VR</scp> Simulation to Teach Trainees in Endoscopic Endonasal Skull Base Approaches

  The Laryngoscope · 2025-10-10

  article

  This study introduces a novel educational framework for endoscopic endonasal skull base surgery that integrates hierarchical task analysis (HTA) and systematic human error reduction and prediction approach (SHERPA) into an immersive virtual reality (VR) simulator. The platform deconstructs complex procedures into structured steps, identifies potential errors, and embeds decision-making prompts to enhance both technical skill and situational awareness. This structured, error-aware VR approach offers a transformative advancement in surgical training, providing a safe, repeatable, and clinically relevant learning environment. Dr. Eugene Chang receives support from the NIH and is an advisor to Sanofi/Regeneron, but this support is not relevant to this study. The other authors declare no conflicts of interest. The data that support the findings of this study are available from the corresponding author upon reasonable request.

  PublisherDOI

• Comparative Analysis of Endoscope Obscuration With Utilization of an Endonasal Access Guide for Endonasal Skull Base Surgery

  Operative Neurosurgery · 2024-07-05 · 2 citations

  article

  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 < .001; 4.19% [CI: 2.83-5.55] vs 12.97% [CI: 10.24-15.70], P < .001) and cleaning actions were also significantly reduced by EAG (0.69/min [CI: 0.39-0.99] vs 1.67/min [CI: 1.34-2.00], P = .001; 0.66/min [CI: 0.35-0.97] vs 1.67/min [CI: 1.34-2.00], P < .001). Between the control and EAG cohorts, there was no significant difference between obscuration time and cleaning actions in the first third (9.33% vs 12.97%, P = .086; 1.34/min vs 1.67/min, P = .151) or in the middle third (6.24% vs 3.73%, P = .140; 0.80/min vs 0.69/min, P = .335), but there was a significant difference in the last third (9.25% [CI: 6.95-11.55] vs 4.19% [CI: 2.83-5.55], P < .001; 0.95/min [CI: 0.73-1.17] vs 0.66/min [CI: 0.35-0.97], P = .018). CONCLUSION: EAG significantly reduces lens obscurations and cleaning events, particularly during the intradural portion of operations. This technology may offer a greater time-saving impact with patients undergoing long EEA operations.

  PublisherDOI

• Immediate procedural safety of adjunctive proximal coil occlusion in middle meningeal artery embolization for chronic subdural hematomas: Experience in 137 cases

  Interventional Neuroradiology · 2024-01-02 · 13 citations

  articleOpen access

  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.

  PublisherOA PDFDOI

• An unusual case of aggressive endometrial adenocarcinoma metastasis to the clivus: illustrative case

  Journal of Neurosurgery Case Lessons · 2024-10-28

  articleOpen accessSenior author

  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. https://thejns.org/doi/10.3171/CASE24392.

  PublisherOA PDFDOI

• Recurrence Rates Following Treatment of Spinal Vascular Malformations: A Systematic Review and Meta-Analysis

  World Neurosurgery · 2023-02-12 · 9 citations

  reviewOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• A Hierarchal Task Analysis for Endoscopic Resection of Pituitary Adenomas

  Journal of Neurological Surgery Part B Skull Base · 2023-02-01 · 1 citations

  article

  Background: Pituitary adenomas are one of the most common skull base procedures performed by otolaryngology and neurosurgery teams. Although complications are rare, when they occur, they can be devastating to patients. The use of SHERPA (Systematic Human Error Reduction and Prediction Approach) has been used in healthcare to reduce human errors, and it is based on a hierarchical task analysis (HTA) in which the systemic details of a procedure are outlined. HTA approaches can also serve as a foundation for bimodal education. Trainees can utilize HTAs of surgical procedures to understand a global perspective and the granular steps required to perform the surgery safely. Mentors can use HTAs as an outline to provide detailed feedback to trainees so that they can improve their surgical proficiency. Moreover, HTAs can also serve as a model for deliberate practice in surgical simulation, in which trainees can gain experience in surgical procedures without putting patients at risk. To our knowledge, there have not been any published HTA approaches to pituitary adenomas outlining both the otolaryngologic and neurosurgical roles.

  PublisherDOI

• Comparative Analysis of Endoscope Obscuration with Utilization of an Endonasal Access Guide for Endonasal Skull Base Surgery

  Journal of Neurological Surgery Part B Skull Base · 2022-02-01 · 1 citations

  article

  Objective: In endoscopic endonasal approaches (EEA) for skull base pathologies, endoscope lens obscuration remains a time-consuming and distracting issue that results in increased operative time. The endonasal access guide (EAG) has been demonstrated as a possible adjunct to minimize obscurations, but no comparative studies have yet been done. This retrospective cohort study aims to determine the efficiency benefits of EAG in EEA.

  PublisherDOI

• Intraoperative Xoran X-Cat Mobile CT Scan: Novel Experience in Endoscopic Endonasal Skull Base Surgery

  Journal of Neurological Surgery Part B Skull Base · 2022-02-01

  article

  Intraoperative real-time imaging with MRI and CT has been used infrequently in skull base surgery over the last two decades and has been limited mostly to academic medical centers. At many centers, including ours, we routinely obtain an immediate postoperative thin-cut CT with axial, sagittal and coronal reconstructions after endonasal skull base surgery to assess for integrity of reconstruction, the presence and degree of pneumocephalus, and the presence of hematoma. Xoran Technologies has developed the X-CT mobile, low-profile, rapid, 45-second, cone beam CT scanner to provide real-time intraoperative or immediate postoperative imaging data while the patient is maintained under general anesthesia prior to the patient leaving the operating room. An IRB-approved pilot study (Western IRB 20190429) was initiated to validate the clinical quality of the X-CT in 20 patients undergoing endoscopic endonasal surgery (macroadenoma: 11, chordoma: 4, skull base meningioma: 3, arachnoid cyst: 1, skull base metastasis: 1). Data collection included specific 6-point imaging criteria of the X-CT images (presence of intracranial air, presence and measurement of midline shift, presence of intraparenchymal or intracranial blood, presence or absence of hydrocephalus, position of bone grafting or fat grafting, position of stents, catheters, and or wires) read by the surgeon. In 20 cases, the surgeon scored the intraoperative study adequate in the scoring scale and clinical utility in 20 cases. An immediate conventional MDCT scan was obtained. The review of the immediate conventional CT scan by the surgeons did not change the clinical impressions or recommendations arrived at with the intraoperative scan. Upon completion of the study, independent radiologist comparison of both imaging studies, side by side was performed to identify if due to imaging quality or intraoperative analysis, discrepancies were found. The results will be reviewed. Additional data collection includes intraoperative scan setup, scan time compared with the time to obtain a conventional scan (9 vs. 20 minutes) and adverse events related to use of the intraoperative CT (none). The radiation dose to the patient was decreased with the intraoperative scan by 42% (CTDI 28.1 mGy intraoperative cone beam and CTDI 48.4 mGy for conventional MDCT scan). This presentation will outline the process our center undertook to integrate the CT scanner into our surgical workflow (including intraoperative video demonstration), examples of imaging quality cone beam intraoperative versus conventional CT scan and provide an initial assessment of potential benefits and limitations of this novel technology. In conclusion, this intraoperative novel technology provides adequate detail and quality and precludes the need for traditional postoperative CT in endoscopic skull base surgery with potential savings in overall procedural efficiency, eliminating patient transportation risk and time and offers the surgical team intraoperative decision making if such events are identified in the operating room while the patient is under general anesthesia ([Figs 1]–[3]).

  PublisherDOI

• Minimally invasive pericranial flap harvest through a supraorbital eyebrow craniotomy: Technical note in salvage skull base reconstruction

  Clinical Neurology and Neurosurgery · 2022-04-26 · 1 citations

  article
  PublisherDOI

Frequent coauthors

• Robert H. Rosenwasser

  Thomas Jefferson University Hospital

  26 shared

• M. Reid Gooch

  Neurological Surgery

  26 shared

• Stavropoula Tjoumakaris

  Thomas Jefferson University Hospital

  26 shared

• Fadi Al Saiegh

  The University of Texas Health Science Center at San Antonio

  26 shared

• Richard F. Schmidt

  Thomas Jefferson University

  26 shared

• Pascal Jabbour

  Jefferson University Hospitals

  22 shared

• Ahmad Sweid

  University of Chicago

  22 shared

• Nikolaos Mouchtouris

  Thomas Jefferson University

  21 shared

Awards & honors

• Neurosurgery Faculty Educator of the Year, 2025
• Neurosurgery Faculty Educator of the Year, 2024
• Neurosurgery Faculty Educator of the Year, 2023