PRISMS

Course overview

A PRISM IS A TRIANGULAR REFRACTING SURFACE WITH AN APEX AND A BASE. THE INCIDENT LIGHT RAY PASSING THROUGH THE PRISM IS REFRACTED SO THAT IT IS BENT TOWARDS THE BASE. THUS THE IMAGE IS SHIFTED TOWARDS THE APEX. THE AMOUNT OF LIGHT REFRACTED THROUGH THE PRISM DEPENDS ON THE POWER OF THE PRISM DEFINED IN PRISM DIOPTERS. PRISMS PLAY AN ESSENTIAL ROLE IN ORTHOPTICS AND ARE INVALUABLE IN AN OPHTHALMOLOGIST'S CLINIC AS THEY HAVE DEFINITIVE OPTICAL, THERAPEUTIC, AND DIAGNOSTIC USES. PRISMS ARE USED IN MANY OPHTHALMIC DEVICES SUCH AS SLIT LAMP BIOMICROSCOPE, APPLANATION TONOMETER, GONIOSCOPE, AND OPERATING MICROSCOPE. THE DIAGNOSTIC USES INCLUDE MEASUREMENT OF SQUINT BY PRISM COVER TEST (KRIMSKY, MODIFIED-KRIMSKY METHOD), SIMULTANEOUS PRISM COVER TEST, MADDOX ROD, MEASUREMENT OF FUSIONAL RESERVE AMPLITUDES, TESTS FOR MICROTROPIA, AND ABNORMAL RETINAL CORRESPONDENCE. THERAPEUTIC USES INCLUDE TREATMENT FOR CONVERGENCE INSUFFICIENCY, DIVERGENCE INSUFFICIENCY, TO RELIEVE DIPLOPIA, AND USE IN NYSTAGMUS PATIENTS. THIS ACTIVITY REVIEWS THE IMPORTANCE OF PRISMS IN EVALUATING AND TREATING PATIENTS WITH SQUINT AND DIPLOPIA. IT HIGHLIGHTS THE INTERPROFESSIONAL TEAM'S APPROACH OF THE INTERPROFESSIONAL TEAM IN ASSESSING AND TREATING THESE CONDITIONS.