Dr. Sanjay Kumar Singh finished his MBBS & MD Ophthalmology from Tribhuvan University Teaching Hospital and did his Fellowship in Cornea and Anterior Segment from L.V. Prasad Institute, Hyderabad, India. He received further training in Lamellar Keratoplasty from pioneer surgeon of Lamellar Keratoplasty Dr. Gerritt Melles from Netherlands Innovative Institute of Ophthalmic Surgeries, Netherlands and Dr. Rajesh Fogla from Apollo Hospital, Hyderabad, India.

Dr. Sanjay K Singh further completed M.Sc. in community Eye Health from London School of Hygiene and Tropical Medicine.

He pioneered Phacoemulsification surgery, advance Pterygium surgery (PERFECT surgery with fibrin glue application), Amniotic membrane transplantation surgeries, and Descemet Membrane Endothelial Keratoplasty surgery in Nepal. He further initiated Zepto Capsulotomy and Phacofragmentation with miLOOP technique in Nepal. He started penetrating Keratoplasty surgeries, advance Corneal surgeries and Collagen Crosslinking services on a regular basis in the eastern region of Nepal. Under his leadership first Ophthalmic pathology laboratory was established at Biratnagar Eye Hospital.

He was the founder medical director of Mechi Eye Care Centre (now known as Mechi Eye Hospital), founder medical director of Biratnagar Eye Hospital and first Nepali Program Director of Eastern Regional Eye Care Program. He was president of Nepal Ophthalmic Society from 2014-2016. He has been appointed as professor of Ophthalmology from National Academy of Medical Sciences in 2015.