ENDOSCOPY CENTER OF LONG ISLAND 711 Stewart Avenue Garden City, NY 11530. Tel: 516-227-ECLI(3254), Fax: 516-998-4078. Endoscopy Center of Long Island (ECLI) are licensed specialists in the early detection, diagnosis and prevention of cancer and gastrointestinal disease of the esophagus, stomach and colon. ECLI provides hospital-like levels of care and service, but in a convenient, comfortable, safe atmosphere that avoids the difficulties and concerns associated with hospitals. The ECLI facility, and our highly qualified, board-certified gastroenterologists, colorectal surgeons, anesthesiologists and pathologists, are all “in-network providers” for most healthcare insurance plans. We are fully licensed by the New York State Department of Health as a freestanding, ambulatory surgical care facility for endoscopic procedures. And we’re accredited by the Accreditation Association for Ambulatory Health Care (AAAHC).