What laser peripheral iridotomy does
Laser peripheral iridotomy creates a small opening in the outer iris. Aqueous humor can then flow from behind the iris to the front without passing through the pupil, which relieves the pupillary block that pushed the iris forward and closed the drainage angle. Iridotomy is the definitive treatment for acute angle closure, and the fellow eye, which shares the same narrow anatomy, is often treated prophylactically. The client's statement that her right eye may need the same laser shows correct understanding.
Why the other eye is at risk
Angle closure usually occurs in eyes with a naturally shallow anterior chamber and narrow angle, a feature that is typically present in both eyes. An acute attack in one eye therefore signals a high risk of a future attack in the other. Prophylactic iridotomy of the untreated eye prevents that attack. Until it is done, the right eye remains vulnerable.
| Client statement | Accurate? | Reason |
|---|
| Lost vision will come back | No | Optic nerve damage is irreversible |
| Right eye may need the same laser | Yes | The fellow eye has the same narrow angle |
| Usual cold tablets are fine now | No | Antihistamines and decongestants can dilate the untreated eye |
| Rest in a darkened room for eye ache | No | Darkness dilates the pupil and can trigger closure |
Teaching after an attack
Glaucoma damages the optic nerve, and vision already lost does not return; treatment protects the vision that remains. Some cold and allergy products contain antihistamines or decongestants that can dilate the pupil, and the untreated right eye can still close, so she should check any such drug with the prescriber or pharmacist first. Dim light dilates the pupil, the very trigger of her attack, so eye pain, halos, or blurred vision require prompt medical care rather than rest in the dark.
Watch out! A darkened room sounds restful and is the advice for many eye conditions, but in angle-closure glaucoma darkness is a trigger. Pain with halos or blurred vision is an emergency.
Exam takeaway
Key point! After iridotomy, the fellow eye is often treated too, lost vision does not return, and drugs or conditions that dilate the pupil must be avoided until both eyes are protected.