Ryan Hsi, MD, FACS

Associate Professor
Department of Urology
Division of Endourology and Stone Disease

Medical School: Loma Linda University, School of Medicine
Residency: University of Washington, School of Medicine
Fellowship: University of California, San Francisco
Clinical Interests: Endourology, Kidney Stones, Laparoscopy and Robotics

Dr. Hsi is an expert in the medical and surgical management of kidney stone disease and co-leads the complex kidney stone clinic.  He leads an active research team and is actively recruiting for several clinical trials.

Positions and Employment

2009-2010     Resident in General Surgery, University of Washington Medical Center
2010-2015     Resident in Urology, University of Washington Medical Center
2015-2016     Laparoscopy & Endourology Fellow at the University of California, San Francisco
2016-             Assistant Professor, Department of Urology, Vanderbilt University Medical Center

Honors and Awards

2018                American Urological Association/Japanese Urological Association Academic Exchange Scholar
2017                Best Reviewer Award, Engineering & Urology Society, AUA Annual Meeting, Boston
2015                Resident as Teacher Award
2015                In-Service Award
2014                1st Place Presentation, J. Tate Mason Award, Northwest Urological Society
2013                Warren H. Chapman Resident Research Award
2013                Best Poster of Session, Imaging/Radiology, AUA Annual Meeting, San Diego
2013                Best Poster of Session, Sexual Function/Dysfunction/Andrology, AUA Annual Meeting, San Diego
2013                Best Abstract. Connors et al. AUA Annual Meeting 2013
2013                NIH Trainee Travel Award, American Society of Andrology, San Antonio TX
2012                1st Place Presentation, J. Tate Mason Award, Northwest Urological Society
2012                Best Poster, International Kidney Stone Institute Stone Meeting, Indianapolis, IN
2012                IVUmed Traveling Resident Scholarship, Ghana, January 2013
2012                Engineering & Urology Society (EUS) Best Paper Award
2011, 2012      Western Section AUA Annual Meeting Scholarship 2011, 2012 
2011                Hirschler Fellowship Award, Department of Urology, University of Washington
2011                Best Poster of Session, Stone Disease, AUA Annual Meeting. Washington D.C. 
2008                Alpha Omega Alpha (AOA), Loma Linda University School of Medicine
2008                First Place, Scientific Poster Session, Annual Postgraduate Convention, Loma Linda
2008                Walter E. Macpherson Society Student-Faculty Research Award, Loma Linda 
2006                Walter E. Macpherson Society Summer Research Scholarship, Loma Linda

Other Experience and Professional Memberships

American Urological Association
Southeastern Section of the American Urological Association
Endourological Society
Vanderbilt Urology Society
American Medical Association
American College of Surgeons, Fellow
Research on Calculus Kinetics (R.O.C.K.) Society
Collaborative for Research in Endourology (CoRE)
Endourology Disease Group for Excellence (EDGE)

Contribution to Science

Clinical outcomes among kidney stone patients

As part of the metabolic stone clinic, I routinely use 24-hour urine collections to evaluate stone recurrence risk.  I have critically evaluated the role of the stone clinic effect and role of the 24-hour urine for preventing stone disease.  I have helped develop a prospective kidney stone registry for patients with kidney stones.  Through this work, we have evaluated the outcomes of patients undergoing ureteroscopy, and of those with cystinuria, a genetic cause of stone disease.

  1. Hsi RS, Sanford T, Goldfarb DS, Stoller ML. “The role of the 24-hour urine collection in the prevention of kidney stone recurrence.” Journal of Urology. 2017 Apr;197(4):1084-1089. PMID: 27746283
  2. Kuebker JM, Robles J, Kramer JJ, Miller NL, Herrell SD, Hsi RS. “Predictors of spontaneous ureteral stone passage in the presence of an indwelling ureteral stent.” Urolithiasis. 2018 Oct 22 [Epub ahead of print]. PMID: 30349974
  3. Chang H, Tzou DT, Usawachintachit M, Duty BD, Hsi RS, Harper JD, Sorensen MD, Stoller M, Sur RL, Chi T. “Rationale and Design of the Registry for Stones of the Kidney and Ureter (ReSKU™): A Prospective, Observational Registry to Study the Natural History of Urolithiasis Patients. Journal of Endourology. 2016 Dec;30(12):1332-1336. PMID: 27758162 PMCID: PMC5144847
  4. Usawachintachit M, Sherer B, Hudnall M, Tzou DT, Taguchi K, Hsi RS, Stoller M, Chi T. “Clinical outcomes for cystinuria patients with unilateral versus bilateral cystine stone disease.” J Endourol. 2018 Feb;32(2):148-153. PMID: 29179563.

Human trials for kidney stones

I have actively participated in several clinical studies for kidney stone disease.  After obtaining FDA approval, we performed the first-in-human clinical study for ultrasound to reposition kidney stones in the urinary system.  I recruited subjects and studied the effect of a renoprotective protocol consisting of low amplitude, low rate shocks at the start of shockwave lithotripsy. The goal of this study was to demonstrate that renal vasoconstriction early during shockwave lithotripsy prevents renal injury.  I helped design and recruit subjects for a randomized controlled trial comparing an analgesic suppository to placebo for post surgical pain after ureteroscopy.

  1. Harper JD, Cunitz BW, Dunmire B, Lee FC, Sorensen MD, Hsi RS, Thiel J, Wessells H, Lingeman JE, Bailey MR. “First-in-human clinical trial of ultrasonic propulsion of kidney stones.” Journal of Urology. 2016 Apr;195(4P1):956-64. PMID: 26521719 PMCID: PMC4851928
  2. Lee FC, Hsi RS, Sorensen MD, Dunmire B, Liu Z, Bailey MR, Harper JD. “Renal vasoconstriction occurs early during clinical SWL using a renal protection protocol.” Journal of Endourology. 2015 Dec;29(12):1392-5. PMID: 26239232 PMCID: PMC4677566
  3. Lee FC, Holt SK, Hsi RS, Haynes B, Harper JD. “Preoperative Belladonna and Opium Suppository for Ureteral Stent Pain: a Randomized, Double-Blinded, Placebo Controlled Study.” Urology. 2017 Feb;100:27-32. PMID: 27658661 PMCID: PMC5448974

Epidemiology and pathophysiology of kidney stones

For over 50 years we have thought that the initiating event for idiopathic calcium stone disease is the Randall plaque, on which stones grow, break off, and become active urinary stones.  Through advanced high-resolution microscopy, we described intratubular mineralization of the renal medullary tissue proximal to the Randall plaque.  These findings may focus the development of therapeutics that would help modulate or slow the mineralization process at the tissue level. These data are supported by epidemiologic work describing the associations of demographics, metabolic syndrome, diet, and vascular disease with kidney stone risk.

  1. Hsi RS, Ramaswamy K, Ho SP, Stoller ML. “The origins of urinary stone disease: upstream mineral formations initiate downstream Randall’s plaque.” BJU Int. 2017; 119(1):177-84. PMID: 27306864 PMCID: PMC5161725
  2. Hsi RS, Kabagambe EK, Shu X, Han X, Miller NL, Lipworth L. “Race- and Sex-related Differences in Nephrolithiasis Risk Among Blacks and Whites in the Southern Community Cohort Study.” Urology. 2018 Aug;118:36-42. PMID: 29753847
  3. Sorensen MD, Hsi RS, Chi T, Shara N, Wactawski-Wende J, Kahn AJ, Wang H, Hou L, Stoller ML. “Dietary Intake of Fiber, Fruit and Vegetables Decrease the Risk of Incident Kidney Stones in Women: A Women’s Health Initiative (WHI) Report.” Journal of Urology. 2014 Dec;192(6):1694-9. PMID: 24859445 PMCID: PMC4241174
  4. Hsi RS, AJ Spieker, ML Stoller, DR Jacobs, AP Reiner, RL McClelland, AJ Kahn, T Chi, M Szklo, MD Sorensen. “Coronary artery calcium score and association with recurrent nephrolithiasis: the Multi-Ethnic Study of Atherosclerosis.” Journal of Urology. 2016; 195(4 Pt 1):971-6. PMID: 26454103 PMCID: PMC4966606

Ultrasonography for kidney stones

I have worked on several projects to improve ultrasound performance for kidney stone imaging.  We have developed several advanced beamforming methods specific for kidney stones.  In addition to studying B-mode adjuncts such as the color Doppler twinkling and stone shadow for improving stone detection, I have studied methods to improve stone sizing. I have worked collaboratively with ultrasound engineers to perform in vitro experiments, and when the algorithms were optimized, I recruited human stone formers for in vivo testing. Several important clinically relevant ultrasound techniques were developed from this work, including utilizing the stone shadow in improve detection specificity and stone sizing. We have also demonstrated that the presence of twinkling improves detection specificity.

  1. Hsi RS, Schlunk SG, Tierney JE, Dei K, Jones R, George M, Karve, P, Duddu R, Byram BC. “Feasibility of non-linear beamforming ultrasound methods to characterize and size kidney stones.” PLoS One Aug 28;13(8:e0203138. PMID: 30153279.
  2. Tierney JE, Schlunk SG, Jones R, George M, Karve P, Duddu R, Byram BC, Hsi RS. “Next-generation ultrasound methods for kidney stone characterization: Feasibility of non-linear beamforming techniques.” Urolithiasis 2019 Apr;47(2):181-8. PMID: 29356874.
  3. Dunmire B, Lee FC, Hsi RS, Cunitz BW, Paun M, Bailey MR, Sorensen MD, Harper JD. “Tools to improve the accuracy of kidney stone sizing with ultrasound.” Journal of Endourology. 2015 Feb;29(2):147-52. PMID: 25105243 PMCID: PMC4313404
  4. Sorensen MD, Harper JD, Hsi RS, Shah AR, Dighe MK, Carter SJ, Moshiri M, Paun M, Lu W, Bailey MR. B-mode Ultrasound Versus Color Doppler Twinkling Artifact in Detecting Kidney Stones.  Journal of Endourology. 2013 Feb;27(2):149-53. PMID: 23067207 PMCID: PMC3573723

Radiation exposure during urologic procedures

Recognizing that medical sources of ionizing radiation comprise the majority of radiation exposure, I sought to describe effective doses during kidney stone surgery and during urodynamics in children.  We found that obesity was a significant risk factor for higher radiation dose, in addition to fluoroscopy time.  We also examined contrast reactions related to urologic radiology imaging studies.

  1. Hsi RS, Harper JD. Fluoroless Ureteroscopy: Zero-dose fluoroscopy during ureteroscopic treatment of urinary tract calculi.  Journal of Endourology. 2013 Apr;27(4)432-7. PMID: 23194092
  2. Hsi RS, Dearn J, Dean M, Zamora D, Kanal K, Harper JD, Merguerian P. “Effective and organ specific doses during pediatric videourodynamics”. Journal of Urology 2013 Oct;190(4):1364-70. PMID: 23707437 PMCID: PMC4843507
  3. Hsi RS, Zamora D, Kanal K, Harper JD. “Severe Obesity is Associated with 3-Fold Higher Radiation Dose Rate During Ureteroscopy”. Urology 2013 Oct;82(4):780-5. PMID: 23958504 PMCID: PMC4843513
  4. Dai JC, Brisbane WG, Chang HC, Hsi RS, Harper JD. “Anaphylactoid Reactions after Instillation of Contrast Material into the Urinary Tract: A Survey of Contemporary Practice Patterns and Review of the Literature.” Urology 2018 Dec;122:58-63. PMID: 30195013

Complete List of Published Work in MyBibliography

Active Clinical Trials

Ureteral Stent Trial

Ureteral Stent Placement After Ureteroscopy for Renal Stones: A Randomized Controlled Trial. The rationale for this study is to determine if there is a difference in complications among patients undergoing ureteroscopy for renal stones who receive a stent compared to not receiving a stent postoperatively.

Learn more about this trial

PI: Ryan Hsi, MD

Kidney Stone Pain (ENORC)

Evaluation of Pain Before and After Removal of Non-obstructive Kidney Stones (ENORC).  The objective of this study is to prospectively determine if the removal of non-obstructing renal calculi can reduce or eliminate participant's pain and/or improve their quality of life.

Learn more about this trial

PI: Ryan Hsi, MD

Struvite Stones Antibiotic

The aim of this research is to determine an effective antibiotic regimen following definitive surgical therapy of kidney stones caused by bacterial infection (struvite stones).

Learn more about this trial

PI: Ryan Hsi, MD; Nicole Miller, MD