Appendix A: Various Ophthalmologic Tests

1. Acuity: Snellen Chart/Card: 20/12 to 20/25 is considered normal

a. For example, 20/80 vision means that they can recognize at 20 feet what the normal can recognize at 80 feet

b. if acuity is less than 20/30 and the pt does not wear corrective lenses, a pinhole occluder will determine if the decreased acuity is due to refractive error

2. Direct Ophthalmoscopy:

3. Schiotz Tonometry: (Intraocular Pressure, Normal Range: 10-21.5 mm Hg), for glaucoma

4. Extraocular Muscle Function: (tests CN III, IV, VI): ask the patient to follow an object in all six directions: right/up, right, right/down, left/up, left, left/down.

5. Anterior Chamber Depth: (Light from Temporal Side), checks for narrow angle glaucoma. If Ant. Chamber Depth is "deep" (normal), there will be no shaded area on the contralateral side. If the depth is "narrow", there WILL be a shaded area on the contralateral side.
6. Fluorescein Staining of Cornea: Yellow-Green dye helpful in diagnosing corneal epithelium defects. Applied via sterile filter-paper strip.

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