Colonoscopy clinicians in San Francisco, California

CMS lists 92 clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice who have billed Medicare for at least one colonoscopy and practice in San Francisco, California (details below).

Colonoscopy volume

Clinician	Colonoscopies billed	Percentile rank
Dennis Shen, MD	503	99%
Jesse Liu, MD	360	97%
Susan Ripper, MD	296	96%
Kenneth Binmoeller, MD	289	95%
James Yan, DO	283	95%
Michael Verhille, MD	281	95%
Annette Kwon, MD	265	94%
Timothy Chen, MD	218	91%
Andrew Nett, MD	216	90%
Natalie Lee, MD	189	87%
Daniel Conlin, MD	186	87%
Robert Elsen, MD	180	86%
Aristotle Mendiola, MD	175	85%
Christopher Hogan, MD	171	84%
Frank Farrell, MD	169	84%
Elijah Verheyen, MD	168	84%
Vikram Malladi, MD	163	83%
Jennifer Frankel, MD	157	82%
Ripple Sharma, MD	151	80%
Sirisha Grandhe, MD	147	79%
Amir Prushani, MD	138	77%
Waseem Ahmad, MD	133	75%
Thomas Myint, MD	124	73%
Myung Ko, MD	123	72%
Jonathan Terdiman, MD	114	69%
Shreya Patel, MD	104	66%
Sara Lewin, MD	103	65%
James Torosis, MD	100	64%
Connie Wang, MD	94	62%
Kevin Man, MD	86	58%
Kendall Beck, MD	84	57%
Cheikh Njie, MD	84	57%
Yen Quang, MD	72	51%
Mimi Lin, MD	70	50%
Patrick Avila, MD	68	49%
Rishika Chugh, MD	68	49%
Ma Somsouk, MD	68	49%
Max Brondfield, MD	66	48%
Justin Field, MD	65	47%
Vicky Yang, MD	61	45%
Colin Feuille, MD	58	44%
Michael Larsen, MD	56	42%
Cathleen Cabansag, MD	55	42%
Priya Kathpalia, MD	55	42%
Tonya Kaltenbach, MD	54	41%
Daniel Rengstorff, MD	54	41%
Justin Sewell, MD	51	39%
Benjamin Yip, MD	50	39%
Sun Chuan Dai, MD	49	38%
Michele Tana, MD	46	36%
Adam Blaisdell, MD	45	36%
Christopher Rombaoa, MD	44	35%
Yongyan Cui, MD	42	34%
Pooja Dharwadkar, MD	41	33%
Maria Duarte, MD	39	32%
Abdul Kouanda, MD	37	31%
James Reed, MD	37	31%
Aparajita Singh, MD	37	31%
Cynthia Leung, MD	34	29%
Ruzbeh Mosadeghi, MD	34	29%
Laura Chiu, MD	33	28%
Arielle Klepper, MD	29	25%
Jacquelyn Maher, MD	25	23%
Dean Rider, MD	25	23%
Uma Mahadevan, MD	24	22%
John Bettinger, MD	22	21%
Nazia Hasan, MD	22	21%
Allyson Richardson, MD	22	21%
Michael Li, MD	20	19%
Vivek Rudrapatna, MD	16	17%
Jin Ge, MD	15	16%
Jennifer Chen, MD	14	15%
Madhuri Badrinath, MD	12	14%
Nancy Ho, MD	12	14%
Rena Mei, MD	12	14%
Elizabeth Adler, MD	1-10	13% or below
Matthew Chang, MD	1-10	13% or below
Jeffrey Fox, MD	1-10	13% or below
Richard Frederick, MD	1-10	13% or below
Gregory Fung, MD	1-10	13% or below
Liat Gutin, MD	1-10	13% or below
Nghiem Ha, MD	1-10	13% or below
Yao Heng, MD	1-10	13% or below
Edward Holt, MD	1-10	13% or below
Farah Kassamali, MD	1-10	13% or below
Neil Mehta, MD	1-10	13% or below
Raphael Merriman, MD	1-10	13% or below
Nizar Mukhtar, MD	1-10	13% or below
Yume Nguyen, MD	1-10	13% or below
Jessica Rubin, MD	1-10	13% or below
Francis Yao, MD	1-10	13% or below
Debra Yen, MD	1-10	13% or below

Sorted by the number of colonoscopies billed to Medicare, highest first, not by quality or skill. CMS suppresses counts between 1 and 10 to protect patient privacy and publishes the range instead.

Understanding CMS Data

CMS's "Colonoscopy" category combines specific billing codes for colonoscopy to calculate the number of times each clinician billed Medicare for a "Colonoscopy." These include screening colonoscopy, diagnostic colonoscopy, and colonoscopy with biopsy or polyp removal. CMS's list also includes flexible sigmoidoscopy and laparoscopic appendectomy, so a clinician's count may include those procedures. CMS counts one procedure per patient per day, so a colonoscopy that included both a biopsy and a polyp removal counts once. CMS reports only procedures that clinicians billed to Original Medicare and Medicare Advantage. Therefore, CMS's procedure volume data does not include procedures that clinicians may have performed on patients who have other health care coverage (e.g., commercial insurance, self-pay, or the VA). Billing variation and coding errors can also affect CMS's data. Therefore, the number of procedures that CMS reports for a clinician may be higher or lower than the actual number of colonoscopies a clinician performed during the reporting period. Lastly, only clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice (as reported to Medicare) are presented.

Source: Centers for Medicare & Medicaid Services (August 18, 2026 release).