Differentiate your conjunctiva from your macula and you'll be on your way to coding bliss. Physicians who treat eye conditions are accustomed to dealing with a wide variety of diagnoses, and it's up to the coder to link the correct ICD-9 codes to the ophthalmology services. Use the anatomic drawing below to locate the part of the eye that your physician addressed, and match that to the sampling of applicable ICD-9 codes in the chart at the bottom of this page.