Dr Khannah graduated from the University of Sydney and underwent specialist training at Sydney Eye Hospital and its affiliated teaching hospitals.
He has special interests in cataract and refractive surgery.
He is a member of the intraocular implant unit for cataract surgery at Sydney Eye Hospital.
Dr Khannah has presented his research at local and international meetings as well as publications in international journals.
He has also recently published a chapter in a book regarding cataract surgery techniques.
He is a Clinical Senior Lecturer in the Department of Ophthalmology at Sydney University and Macquarie and a Staff Specialist at Sydney Eye Hospital.