Funduscopic Exam

Aka: Funduscopic Exam, Ophthalmoscopy, Retinal Exam

1. See Also
   1. Retinal Anatomy
   2. Funduscopic Changes in Hypertension
2. Preparation: Pupil Dilation
   1. See Mydriatics
   2. Tropicamide 0.5% - 1% (Mydriacyl)
      1. Onset: 20-40 minutes
      2. Duration: 4-8 hours in most cases (may last as long as 24 hours)
      3. Blue eyes more sensitive, lasts longer
      4. Start with 0.5% concentration
   3. Phenylephrine hydrochloride 2.5% (Ak-Dilate, Mydfrin)
      1. Onset: 30-60 minutes
      2. Duration: 3-5 hours
   4. Contraindications to dilation
      1. Shallow anterior chamber OR angle-closure Glaucoma
         1. Diagnostic exam Mydriatic use is safe (see Mydriatic)
      2. Following pupillary signs after Head Injury
      3. Iris supported intraocular lens implantation
         1. (square/hexagonal pupil 'sputnik')
3. Exam: Protocol
   1. Red Reflex
   2. Optic Disc
      1. Clarity of disc (evaluation for Papilledema)
      2. Cup Disc Ratio
         1. Ratio of horizontal diameter of the cup to disc
         2. Abnormal Cup:Disc >0.5 suggests Glaucoma
   3. Retinal Circulation
      1. Venous pulsations
   4. Macula
   5. Retinal Background
4. Findings
   1. Increased Intracranial Pressure
      1. Papilledema
      2. Absent venous pulsations
   2. Retinal or subhyoid Hemorrhage
   3. Blood in center of disc
      1. Suggests Subarachnoid Hemorrhage
   4. Choked disc with engorged veins
      1. Suggests Methanol Intoxication
   5. Retinal Artery Occlusion
      1. Retina appears pale-gray due to Retinal edema
      2. Macula with cherry-red spot on white-yellow background
      3. Constricted arterioles
      4. Box-Carring of Retinal vessels
         1. Retinal vessels with interrupted columns of blood appear as train box cars
      5. Hollenhorst Plaques (emboli)
         1. "Glistening orange yellow flakes"
         2. Represent fragmented emboli at arteriole bifurcation
   6. Retinal Vein Occlusion
      1. Retinal veins dilated tortuous
      2. Blood streaked Retina (esp. in ischemic type)
         1. Diffuse Retinal Hemorrhages radiating from optic disc ("Blood and thunder Retina")
   7. Glaucoma
      1. General
         1. Focal thinning of neural rim
            1. Nerves at edge of cup and edge of disc
            2. Thinning seen at temporal (lateral) disc margin
         2. Superficial Hemorrhage overlying disc edge
      2. Diagnostic changes
         1. Symmetrically enlarged cup-to-disc ratio >0.5 or
         2. Cup-to-disc ratio difference between eyes >0.2 or
         3. Significantly asymmetric cup in one eye
   8. Diabetic Retinopathy
      1. Nonproliferative Retinopathy
         1. Retinal veins dilated
         2. Cotton Wool exudates or spots
         3. Hard exudates
         4. Macular edema
         5. Intraretinal Hemorrhages
         6. Microaneurysms
      2. Proliferative Retinopathy
         1. Neovascularization
         2. Preretinal Hemorrhages
         3. Vitreous Hemorrhages
         4. Vascular fibrosis