Technical Sergeant Gary McCullers, USAF, (left), Non-Commissioned Officer In Charge (NCOIC) of the Optometry Clinic, 48th Aerospace Medical Squadron, 48th Fighter Wing, RAF Lakenheath, UK, uses a Non-Contact Tonometry (NCT) machine on AIRMAN First Class Thomas Bangle from the 48th Equipment Maintenance Squadron. The NCT is used to measure the internal pressure in the eye as part of the test for glaucoma