Norm of Oculoplethysmography (OPG)
Negative, or all pulses should occur simultaneously.
Usage of Oculoplethysmography (OPG)
Ataxia, status after carotid endarterectomy, syncope, and transient ischemic attacks.
Description of Oculoplethysmography (OPG)
Noninvasive test that measures ocular artery pressure by comparing pulse arrival times in the eyes with the ears, which reflects the adequacy of cerebrovascular blood flow in the carotid arteries.
Professional Considerations of Oculoplethysmography (OPG)
Consent form IS required.
Clients who have had eye surgery within 2–6 months, cataract, conjunctivitis, diabetes mellitus, uncontrolled glaucoma, enucleation, history of retinal detachment or lens implantation, clients who are hypersensitive to local anesthetic, or uncooperative and combative clients.
- Obtain anesthetic eye drops, an eyecup, and photoelectric cells.
- Instill the anesthetic eye drops and apply the eyecup to the corneas with light suction (40–50 mm Hg).
- Apply the photoelectric cells to earlobes.
- Record the cyclic changes in volume on a graphic machine.
- Observe for ocular pain or photophobia, which may indicate corneal abrasion.
Client and Family Teaching
- Do not rub the eyes or insert contact lenses for 30 minutes after the test.
- Anesthetic eye drops may cause slight temporary burning.
- It is not unusual to experience blurred vision for a short period after this procedure.
- Continued blurred vision or pain should be reported to the physician.
- The procedure takes a few minutes.
Factors That Affect Results
- Constant blinking, nystagmus, or poor cooperation prevent accurate measurement.
- A 20-msec or greater delay in the pulse wave in the ophthalmic artery is abnormal, signifying stenosis.
- Delayed arrival of the ocular pulse is associated with ipsilateral carotid stenosis.
- This test does NOT distinguish between a completely occluded internal carotid artery and one that is nearly occluded.
- This procedure is extremely useful for evaluating deep orbital circulation.
- See also Carotid phonoangiography and oculopneumoplethysmography (OPPG).