About

M. Sean Grady is an Emeritus Professor of Neurosurgery at the Perelman School of Medicine, University of Pennsylvania. He serves as an Attending Neurosurgeon at The Children's Hospital of Philadelphia and is the Medical Director of the Penn Neuroscience Service Line at The Hospital of the University of Pennsylvania. Dr. Grady was appointed the Charles Harrison Frazier Professor and Chairman of the Department of Neurosurgery at the Perelman School of Medicine in March 1999. His educational background includes a B.A. in Biology from the University of California, San Diego, obtained in 1977, and an M.D. from Georgetown University School of Medicine in 1981. He trained in Neurological Surgery at the University of Virginia from 1981 to 1987 and was a faculty member at the University of Washington from 1987 to 1999. Dr. Grady is Board Certified by the American Board of Neurological Surgeons and is a fellow of the American College of Surgeons. His research interests include memory dysfunction resulting from traumatic brain injury and minimally invasive neurosurgery. His clinical expertise encompasses Cranial Base Tumors, Pituitary Tumors, Meningiomas, Schwannomas, Malignant Skull Base Tumors, Cerebrovascular Disorders, Aneurysms, and AVMs. He is also co-director of the Cranial Base Center and performs general neurosurgery procedures for herniated discs of the back and neck.

Research topics

• Medicine
• Surgery
• Neuroscience
• Anesthesia
• Pathology

Selected publications

• Pituitary Apoplexy Precipitated by Noncranial Surgeries

  Journal of Neurological Surgery Part B Skull Base · 2025-02-01

  article
  PublisherDOI

• Pituitary Apoplexy Precipitated by Non-Cranial Surgeries: An Institutional Experience

  Journal of Neurological Surgery Part B Skull Base · 2025-05-14

  articleOpen access

  Introduction: Pituitary apoplexy (PA) is a rare, acute condition caused by hemorrhage or infarction within the pituitary gland, primarily associated with preexisting adenomas. Classically, PA presents with severe headache, neuro-ophthalmologic deficits, and/or endocrine disturbances. While the mechanisms of PA are under investigation, vascular changes, blood flow disruptions, and intrasellar pressure are implicated. We report the first 6-year institutional experience of risk factors of PA associated with non-cranial surgeries. Methods: A retrospective review was conducted of patients presenting with PA from July 2017 to January 2024. Patients diagnosed with PA within 1 week of non-cranial surgery were included. Data encompassed medical history, surgical details, presenting symptoms, imaging, and outcomes. Results: Among 56 PA patients, 4 (7.1%) occurred after non-cranial surgeries, including cardiac procedures, mandibulectomy, and toe amputation. Three male patients (one excluded due to incomplete data) presented with oculomotor deficits and endocrine dysfunction. All had lesions greater than 2 cm. Common risk factors included hypertension, significant intraoperative blood pressure fluctuations (systolic range: 60-200 mm Hg), and lengthy anesthesia (average: 9.09 hours). Symptom onset occurred within 24 hours postsurgery. Conclusion: Despite differences in surgical context, several factors seemed to predispose these patients to PA: wide fluctuations in intraoperative blood pressure, preexisting hypertension, and macroadenomas exceeding 2 cm. In patients with known macroadenomas, risk stratification may be helpful based on adenoma size and comorbid conditions affecting vascular health. Sudden intraoperative changes in blood pressure should be avoided. For those with predisposing risk factors undergoing high-risk surgeries, especially cardiac procedures that utilize anticoagulation, obtaining a preoperative computed tomography (CT) head may be warranted.

  PublisherOA PDFDOI

• The Somatotroph-Secreting Pituitary Adenoma Experience in Socialized versus Mixed Private/Public Health Care Systems: A Comparison of Surgically Treated Acromegaly in NZ and the US

  Journal of Neurological Surgery Part B Skull Base · 2024-02-01

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  Introduction: Pituitary adenomas have recently been proposed as a barometer for health care access in the United States, given recognition that insurance status impacts diagnosis, treatment, and outcomes for affected patients. Growth hormone (GH)-secreting pituitary adenomas causing acromegaly represent a rare subset of this condition, possessing a high socioeconomic burden due to the multiple downstream effects of GH on the cardiovascular and metabolic systems. Patients with functioning tumors are thought to present before their tumors reach classification as macroadenomas (>10 mm in size). However, it is conceivable that this may be influenced by health care access and it remains to be evaluated whether this is true across different health care funding systems worldwide.

  PublisherDOI

• A phenomenon not to be missed: delayed postoperative cerebrospinal fluid rhinorrhea following no identifiable intraoperative leak in sellar surgery.

  PubMed · 2024-12-01 · 1 citations

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  PublisherDOI

• Impact of Patient Demographics and Socioeconomic Status on Surgical Outcomes in Endonasal Endoscopic Pituitary Surgery

  Journal of Neurological Surgery Part B Skull Base · 2024-02-01

  article

  Introduction: Sociodemographic determinants of healthcare outcomes are well documented across many fields of surgical diseases. We investigated the impact of race, gender, and median household income on the costs and surgical outcomes of patients undergoing endonasal endoscopic pituitary surgery to determine the role of these determinants.

  PublisherDOI

• Multi‐institutional Analysis of Endoscopic Sellar Surgical Volumes During the COVID‐19 Pandemic

  Otolaryngology · 2023-08-25 · 2 citations

  article

  OBJECTIVE: We sought to quantify trends in operative volumes and complications of endoscopic sellar surgery before and after the COVID-19 pandemic onset. STUDY DESIGN: We performed a retrospective analysis. SETTING: TriNetX database analysis. METHODS: All adults undergoing neuroendoscopy for resection of pituitary tumor (Current Procedural Terminology code 62165) with diagnosis of benign/malignant neoplasm of pituitary gland (D35.2/C75.1) or benign/malignant neoplasm of craniopharyngeal duct (D35.3/C75.2) were included using the TriNetX database for 2 years before (pre-COVID group) and 2 years after (post-COVID group) February 17, 2020. RESULTS: A total of 1238 patients in the pre-COVID group and 1186 patients in the post-COVID group were compared. Age, gender, and race were statistically similar between the groups (P > .05). Surgical volume decreased by 6% in the post-COVID group. In 2020 Q2, operative volume decreased by 19%, and in 2021 Q4 (peak COVID-19 caseload in the United States), operative volumes decreased by 29% compared to 2 years prior. Postoperative complications including meningitis (P = .49), cerebrospinal fluid leak (P = .36), visual field deficits (P = .07), postoperative pneumonia or respiratory failure (P = .42), and 30-day readmission rates (P = .89) were similar between the 2 groups. CONCLUSION: Overall, endoscopic sellar surgery may continue to fluctuate with increased COVID-19 outbreaks. Patient outcomes do not appear to be worsened by decreased operative volumes or delays in nonurgent surgeries.

  PublisherDOI

• Idiopathic Intracranial Hypertension Is Associated with Recurrent CSF Leak and Reoperation for Spontaneous Temporal Encephalocele

  Journal of Neurological Surgery Part B Skull Base · 2023-10-25 · 2 citations

  articleOpen accessSenior author

  Abstract Objective Spontaneous temporal encephaloceles (STEs) are increasingly recognized as sequelae of idiopathic intracranial hypertension (IIH), which in turn may further complicate their management. We endeavored to review the University of Pennsylvania institutional experience on operative management of STEs, with a focus on factors which may influence surgical outcomes, particularly IIH. Design Retrospective chart review over 9 years from 2013 to 2022. Setting Single-center, two-hospital, tertiary care, academic setting. Participants Patients undergoing middle cranial fossa (43.9%), transmastoid (44.9%), or combined (11.2%) approaches for repair of STEs during the study period (n = 107). Main Outcome Measures Postoperative complication rates, recurrence, and diagnosis of IIH. Results The majority of patients were female (64.5%), with a mean body mass index (BMI) of 37 kg/m2 and mean age of 57 years. Twelve patients (9%) represented reoperations after failed primary repairs. Fourteen percent of patients undergoing primary surgical repair of STE were diagnosed with IIH, compared with 42% of patients undergoing reoperations (p = 0.015). In addition, there was a significant difference in the average BMI of patients undergoing primary (36.4 kg/m2) versus revision surgery (40.9 kg/m2, p = 0.04). Half of those undergoing reoperation were placed on postoperative acetazolamide compared with 11% of patients undergoing primary operations. No patient experienced recurrent leak after reoperation. Conclusion Based on our institutional experience, elevated BMI and the presence of IIH are significant predictors of reoperation for STE. In our experience, acetazolamide is a common adjunct management strategy in addition to reoperation for patients with recurrent cerebrospinal fluid leak in the setting of STE.

  PublisherOA PDFDOI

• The use of aprepitant for the prevention of postoperative nausea and vomiting in endoscopic transsphenoidal pituitary surgery

  International Forum of Allergy & Rhinology · 2023-06-11 · 5 citations

  article

  BACKGROUND: Postoperative nausea and vomiting (PONV) are adverse effects after surgery, which may increase the risk of complications. Aprepitant is a neurokinin-1 receptor blocker and has been shown to reduce chemotherapy-related nausea and vomiting and PONV. However, its role in endoscopic skull base surgery remains unclear. The purpose of this study was to evaluate the effect of aprepitant in reducing PONV in endoscopic transsphenoidal (TSA) pituitary surgery. METHODS: A retrospective chart review between July 2021 and January 2023 of 127 consecutive patients who underwent TSA was performed at a tertiary academic institution. Patients were divided into 2 groups based on preoperative aprepitant use. Two groups were matched based on known risk factors of PONV (age, sex, nonsmoking, and history of PONV). The primary outcome was the incidence of PONV. Secondary outcome measures included the number of anti-emetic use, length of stay, and postoperative cererebrospinal fluid (CSF) leak. RESULTS: After matching, 48 patients were included in each group. The aprepitant group demonstrated a significantly lower incidence of vomiting than the non-aprepitant group (2.1% vs 22.9%, p = 0.002). The number of nausea episodes and anti-emetic use decreased with aprepitant use (p < 0.05). There was no difference in the incidence of nausea, length of stay, or postoperative CSF leak. Multivariate analysis demonstrated that aprepitant decreased the incidence of postoperative vomiting with odds ratio of 0.107. CONCLUSION: Aprepitant may serve as a useful preoperative treatment to reduce PONV in patients undergoing TSA. Further studies are needed to evaluate its impact in other arenas of endoscopic skull base surgery.

  PublisherDOI

• Possible new phase transition in the 3D Ising Model associated with boundary percolation

  arXiv (Cornell University) · 2023-01-20

  preprintOpen access1st authorCorresponding

  In the ordered phase of the 3D Ising model, minority spin clusters are surrounded by a boundary of dual plaquettes. As the temperature is raised, these spin clusters become more numerous, and it is found that eventually their boundaries undergo a percolation transition when about 13\% of spins are minority. Boundary percolation differs from the more commonly studied site and link percolation, although it is related to an unusual type of site percolation that includes next to nearest neighbor relationships. Because the Ising model can be reformulated in terms of the domain boundaries alone, there is reason to believe boundary percolation should be relevant here. A symmetry-breaking order parameter is found in the dual theory, the 3D gauge Ising model. It is seen to undergo a phase transition at a coupling close to that predicted by duality from the boundary percolation. This transition lies in the disordered phase of the gauge theory and has the nature of a spin-glass transition. Its critical exponent $ν\sim 1.3$ is seen to match the finite-size shift exponent of the percolation transition further cementing their connection. This predicts a very weak specific heat singularity with exponent $α\sim -1.9$. The third energy cumulant fits well to the expected non-infinite critical behavior in a manner consistent with both the predicted exponent and critical point, indicating a true thermal phase transition. Unlike random boundary percolation, the Ising boundary percolation has two different $ν$ exponents, one associated with largest-cluster scaling and the other with finite-size transition-point shift. This suggests there are two different correlation lengths present.

  PublisherOA PDFDOI

• Postoperative Cerebrospinal Fluid Leaks following No Intraoperative Leak: A Multi-institutional Study

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

  article

  Objective: Despite widespread adoption and increasing proficiency with endoscopic endonasal approaches (EEA) to the skull base, postoperative cerebrospinal fluid (CSF) leaks are a well-described complication, and thus skull base reconstruction remains an area of interest and potential improvement. There are numerous anecdotal accounts of postoperative CSF leaks which occur following surgery for which there was no apparent intraoperative CSF leak. In this multi-institutional study, we investigate these rare cases and aim to determine predictive factors and strategies for treatment and mitigation.

  PublisherDOI

Recent grants

• NIH Grant R01NS033107

  NIH · $474k · 1999

• NIH Grant K08NS001371

  NIH · $384k · 1994

• Brain Injury Training Grant

  NIH · $5.6M · 2003–2028

• NIH Grant R01NS050598

  NIH · $1.7M · 2011

Frequent coauthors

• H. Richard Winn

  93 shared

• David W. Newell

  49 shared

• Matthew A. Howard

  47 shared

• Peter D. LeRoux

  Bassett Medical Center

  38 shared

• R. C. Ritter

  26 shared

• G. T. Gillies

  22 shared

• Michael M. Haglund

  21 shared

• Donald O. Maris

  University of Washington

  20 shared

Awards & honors

• Charles Harrison Frazier Professor & Chairman of the Departm…