Ambulatory Surgery

Leona M. and Harry B. Helmsley Ambulatory Surgical Center

Located at 55 Holly Hill Lane, Greenwich, CT
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ONS surgeons perform same-day surgical procedures on Wednesdays and Thursdays at the Leona M. and Harry B. Helmsley Ambulatory Surgical Center on Holly Hill Lane.
The Ambulatory Surgery Center is comprised of four operating rooms that are equipped with the most advanced technology, including high-definition video cameras for arthroscopic procedures, state-of-the-art surgical equipment, and a full-service sterile processing facility. In the post-operative area, there are ten beds and a central nursing station. The facility is optimized for the highly-skilled staff to provide personalized patient care in an attractive, comfortable atmosphere designed to put patients at ease.



Surgeries are performed only by ONS surgeons and are not assisted by hospital residents or fellows.

“The experience [of my surgery at the 55 Holy Hill surgery center] was nothing short of perfect. From the moment I exited the elevator and was greeted by the pre-op person at the desk to meeting with my assigned nurse to the team who set up my IV and got me comfortable to the nurses that checked my meds and filled out forms- everyone was cheery and well trained. They knew my name, assured me that Dr. Clain was on schedule, asked if I had questions, etc. It’s as if someone had given them a speech that morning that said, ‘today will be the best day we ever had’. I’ve had numerous other surgeries before (unfortunately), so I can say without a doubt that the 55 Holly Hill team were far and away the best I’ve ever had.” Bill A. Greenwich, CT