About

Gregory E. Tasian, MD, MSc, MSCE, is a Professor of Surgery at the Perelman School of Medicine at the University of Pennsylvania. He serves as an Attending Physician in the Division of Urology at The Children's Hospital of Philadelphia, where he is also a Faculty Member of the Kidney Stone Center, the Center for Clinical Futures, and PolicyLab. Dr. Tasian is the Surgical Director of the Kidney Stone Center and holds the Endowed Chair in the Clinical Epidemiology of Pediatric Urologic Disease. He is the Director of the Center for Outcomes Research in Surgery (CORES) at Children's Hospital of Philadelphia. His educational background includes a BA in Biology and English from Trinity University (2000), an MSc in Neuroscience from the University of Oxford (2004), an MD from Baylor College of Medicine (2005), and an MSCE in Clinical Epidemiology from the University of Pennsylvania (2014). His research focuses on pediatric urology, particularly kidney stones, cryptorchidism, and related conditions, with contributions to clinical effectiveness, disease recurrence, and epidemiology in pediatric populations.

Research topics

• Internal medicine
• Medicine
• Intensive care medicine
• Environmental health
• Surgery
• Physiology
• Nursing
• Pediatrics
• Physical therapy
• Bioinformatics
• Biology

Selected publications

• IP46-06 PATIENT QUALITY OF LIFE AND CAREGIVER STRAIN AFTER URETEROSCOPY FOR STONE DISEASE

  The Journal of Urology · 2026-04-27

  article
  PublisherDOI

• Handle with care: ureteral access sheath positioning modulates intrarenal pressure—insights from an EAU endourology ex vivo study using four ureteroscope sizes

  World Journal of Urology · 2026-01-22

  article
  PublisherDOI

• Prevention of urinary stones with hydration: a randomised clinical trial of an adherence intervention

  The Lancet · 2026-03-01 · 4 citations

  articleOpen access
  PublisherOA PDFDOI

• Influence of a Prospective Multicenter Clinical Trial on Adherence to Imaging Acquisition and Office Visit Follow-Up After Kidney Stone Surgery: A Bi-Institutional Experience

  Journal of Endourology · 2026-01-14

  articleOpen access

  Introduction: Participation in a clinical trial has been shown to influence medical adherence. We compared postoperative imaging completion and office visit attendance between patients enrolled in the Pediatric KIDney Stone (PKIDS) Trial and those who were not at two participating institutions. We hypothesized that study enrollment would improve adherence to postoperative follow-up. Methods: A retrospective review of patients (8–21 years) undergoing kidney stone surgery during the PKIDS study period was performed at two geographically different PKIDS institutions. Medical records were reviewed for completed imaging and follow-up office visits. The primary outcome was postoperative imaging acquisition within 8 weeks of surgery in alignment with the PKIDS protocol. Secondary outcomes included imaging acquisition by 16 weeks and postoperative office visit attendance by 8 and 16 weeks. Multivariable logistic regression assessed factors influencing adherence. Results: A total of 181 patients were included: 120 PKIDS vs 61 non-PKIDS. 51.9% of patients completed imaging at 8 weeks. PKIDS enrollment was not associated with imaging acquisition at 8 weeks or any secondary outcomes on univariate or multivariable analyses. A higher national Area Deprivation Index percentile (i.e., higher neighborhood-level deprivation) was associated with lower imaging acquisition on multivariable analysis (Odds ratio [OR] 0.98, 95% confidence interval [CI]: 0.97–0.99, p = 0.03). Conversely, private insurance was associated with higher attainment of imaging (OR 2.36, 95% CI: 1.09–5.12, p = 0.03) and office visit attendance within 16 weeks (OR: 3.08, 95% CI: 1.42–6.69, p < 0.01). There were no variables associated with 8-week postoperative office visits. Conclusions: PKIDS trial enrollment was not associated with increased adherence to postoperative follow-up in two geographically different PKIDS sites. This study supports the generalizability of the PKIDS study to non-PKIDS participants and future use of the PKIDS dataset to examine determinants of postoperative care in pediatric kidney stone disease.

  PublisherDOI

• IP06-18 POST-OPERATIVE TRAJECTORIES OF PAIN INTERFERENCE AND INTENSITY AFTER URETEROSCOPY FOR NEPHROLITHIASIS IN YOUTH: A PKIDS STUDY

  The Journal of Urology · 2026-04-27

  article
  PublisherDOI

• Sex-Based Differences in Imaging-Derived Body Composition and Their Association with Clinical Malnutrition in Abdominal Surgery Patients

  Nutrients · 2026-03-05

  articleOpen access

  Background: Malnutrition significantly impacts surgical outcomes yet is difficult to identify preoperatively. Few studies have investigated the association between comprehensive body composition assessment and malnutrition in males and females separately. This study evaluates sex-specific associations between preoperative imaging-derived body composition features and malnutrition in abdominal surgery patients. Methods: This cross-sectional study included patients who underwent a preoperative abdominal computed tomography scan and elective abdominal surgery at a single institution (2018–2021). A deep learning algorithm quantified five muscle groups and two fat depots from CT scans. Clinical malnutrition was diagnosed by registered dietitians using standardized criteria. Sex-specific associations between imaging features and malnutrition were evaluated using logistic regression. Results: Among 1143 patients, 20.2% had clinical malnutrition, with prevalence varying by procedure type (3.5–38.2%). Malnutrition was associated with reduced muscle volume for both sexes; however, myosteatosis was only associated with malnutrition in females. In males, malnutrition was associated with decreased psoas volume (OR: 0.58, 95% CI [0.41–0.82]), decreased quadratus lumborum volume (OR: 0.52, 95% CI [0.35–0.77]), and reduced erector spinae attenuation (OR 0.58, 95% CI [0.41–0.82]). In females, decreased psoas volume (OR 0.56, 95% CI [0.41–0.77]) and attenuation (OR 0.59, 95% CI [0.44–0.79]) were associated with malnutrition. Both sexes showed increased subcutaneous fat attenuation (males: OR 1.58, 95% CI [1.22–2.04]; females: OR 1.96, 95% CI [1.54–2.50]) and visceral fat attenuation (males: OR 1.43 95% CI [1.07–1.90]; females: OR 1.68 95% CI [1.29–2.20]) associated with malnutrition. Conclusions: Males and females exhibit distinct body composition features associated with clinical malnutrition. Comprehensive analysis of muscle and fat characteristics reveals these sex-specific relationships, providing foundational knowledge for future development of predictive tools to enable earlier identification of patients at higher nutrition-related surgical risk.

  PublisherOA PDFDOI

• IP32-06 MACHINE LEARNING ANALYSIS OF VIDEOURODYNAMICS TO PREDICT INCIDENT HYDRONEPHROSIS IN PATIENTS WITH SPINA BIFIDA: EXTERNAL VALIDATION

  The Journal of Urology · 2026-04-27

  article
  PublisherDOI

• Postoperative Symptom Severity and Time Course After Bilateral Ureteroscopy With Stents: Results From the Study to Enhance Understanding of Stent-associated Symptoms

  Urology · 2025-09-11

  articleOpen access
  PublisherOA PDFDOI

• Factors Influencing Postoperative Adherence after Pediatric Kidney Stone Surgery in Alabama (USA): A Single-Institution Retrospective Analysis

  Journal of Endourology · 2025-09-10

  articleOpen access

  Introduction: Pediatric kidney stone disease is on the rise, and high recurrence rates necessitate consistent postoperative follow-up. Identifying social determinants of health is a key step in understanding the factors that influence adherence to follow-up after operation. This study examines socioeconomic associations with adherence after kidney stone procedure in children and evaluates whether enrollment in a multi-center clinical incentivized trial was associated with adherence. We hypothesize that those who lived farther from our hospital, lived in areas of higher deprivation, or were not enrolled in the trial were less likely to follow-up. Methods: We conducted a retrospective review of patients under 18 years old who underwent kidney stone operation from August 2019 to July 2023. Demographics, medical history, Area Deprivation Index (ADI) scores, and surgical details were analyzed. The primary outcome was follow-up clinic attendance within 16 weeks postoperation. ADI was calculated using patient home address to rank against other neighborhoods in the United States. Higher ADI score indicates more socioeconomic disadvantage. Variables were analyzed using chi-square tests for categorical variables and independent t -tests for continuous variables. Results: A total of 120 patients were identified: predominantly female (75/120, 62.5%), White (102/120, 85.0%), with median age of 15.7 years (interquartile range 11.5–17.2). Median travel distance to hospital was 51.0 miles. Of the 120 patients, 66 (55.0%) followed up within 16 weeks. Adherence was higher among patients with private insurance ( p = 0.03) and lower ADI scores (less neighborhood-level deprivation) ( p < 0.01). Prior surgical stone removal was also associated with lower adherence ( p < 0.01). Enrollment in a clinical trial did not significantly impact imaging adherence ( p = 0.98). Conclusion: Private insurance and lower ADI scores were associated with improved follow-up adherence, emphasizing the association of socioeconomic factors with adherence after kidney stone procedure. Clinical trial enrollment did not affect follow-up adherence, suggesting a need for targeted strategies to support high-risk pediatric patients.

  PublisherDOI

• Validation of an Automated CT Image Analysis in the Prevention of Urinary Stones with Hydration Trial

  Journal of Endourology · 2025-08-26 · 2 citations

  articleOpen access1st author

  Introduction and Objective: Kidney stone growth and new stone formation are common clinical trial endpoints and are associated with future symptomatic events. To date, a manual review of CT scans has been required to assess stone growth and new stone formation, which is laborious. We validated the performance of a software algorithm that automatically identified, registered, and measured stones over longitudinal CT studies. Methods: We validated the performance of a pretrained machine learning algorithm to classify stone outcomes on longitudinal CT scan images at baseline and at the end of the 2-year follow-up period for 62 participants aged >18 years in the Prevention of Urinary Stones with Hydration (PUSH) randomized controlled trial. Stones were defined as an area of voxels with a minimum linear dimension of 2 mm that was higher in density than the mean plus 4 standard deviations of all nonnegative HU values within the kidney. The four outcomes assessed were: (1) growth of at least one existing stone by ≥2 mm, (2) formation of at least one new ≥2 mm stone, (3) no stone growth or new stone formation, and (4) loss of at least one stone. The accuracy of the algorithm was determined by comparing its outcomes to the gold standard of independent review of the CT images by at least two expert clinicians. Results: The algorithm correctly classified outcomes for 61 paired scans (98.4%). One pair that the algorithm incorrectly classified as stone growth was a new renal artery calcification on end-of-study CT. Conclusions: An automated image analysis method validated for the prospective PUSH trial was highly accurate for determining clinical outcomes of new stone formation, stone growth, stable stone size, and stone loss on longitudinal CT images. This method has the potential to improve the accuracy and efficiency of clinical care and endpoint determination for future clinical trials.

  PublisherOA PDFDOI

Recent grants

• Anatomic biomarkers of chronic kidney disease progression among children

  NIH · $469k · 2019–2022

• Harnessing Behavior to Decrease Urinary Stone Disease Morbidity Research Project

  NIH · $5.3M · 2016–2026

• Comparative effectiveness of balanced fluids versus normal saline to reduce acute and chronic kidney disease in children with sepsis

  NIH · $15.5M · 2017–2027

• NIH Grant K23DK106428

  NIH · $836k · 2020

Frequent coauthors

• Charles D. Scales

  68 shared

• Susan L. Furth

  Children's Hospital of Philadelphia

  55 shared

• Hussein R. Al‐Khalidi

  Clinical Research Institute

  49 shared

• Michelle Denburg

  Children's Hospital of Philadelphia

  45 shared

• Justin Ziemba

  41 shared

• Jonathan S. Ellison

  Medical College of Wisconsin

  40 shared

• Lihai Song

  Children's Hospital of Philadelphia

  36 shared

• David I. Chu

  Lurie Children's Hospital

  32 shared

Education

• MSCE

  University of Pennsylvania

  2014