Colon & Rectal Surgery Associates of Nashville was established in July 1986 by Dr. Michael Santi as Nashville’s first and only surgical practice solely dedicated to the prevention, diagnosis and surgical treatment of colon, rectum, and anus.  Dr. Santi sought to provide comprehensive colorectal specialty care from preventative cancer screening to advanced surgical treatment of colon and rectal cancer, and we continue that vision today. Through the use of time-honored surgical techniques coupled with embracing the latest innovations in surgical management of colorectal and anal diseases, Dr. Jason Aston and Dr. Keith Hollister are able to provide state-of-the-art care for their patients, leading to fewer complications, increased satisfaction, and better long-term outcomes.

In addition to the diagnosis and surgical management of colon and rectal cancer, Drs. Aston and Hollister specialize in the evaluation and treatment of a wide variety of diseases of the anus, fecal incontinence, colonoscopy, inflammatory bowel disease, diverticulitis, anal fissure, anal fistula, and hemorrhoids.

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Robotic Surgery

Our surgeons are trained and certified in Robotic Surgery using the DaVinci Xi Surgical System © to provide the latest innovation in abdominal surgery

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Laparoscopic surgery

We employ skilled expertise in minimally invasive, laparoscopic surgical options, leading smaller incisions, to shorter hospital stays, and less post-operative pain

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Anal Manometry

By using State-of-the-Art technology to assess the anatomy and function of the anal sphincter, we provide gold-standard treatment options in patients with fecal incontinence

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Our surgeons are skilled in endoscopy for the screening and diagnosis of colon cancer, inflammatory bowel disease, and other colon disorders

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Transanal Surgery

By using the latest techniques in transanal surgery, we can achieve similar results without the use of incisions from major surgery

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Open Surgery

For patients who are not candidates for our minimally invasive surgical options, our surgeons have a combined 20 years of experience in open surgical techniques