Introduction
Penalization is a form of treatment that corrects vision in a ‘weak’ eye. It involves blocking or blurring a patient’s visually good eye to make use of the ‘weak’ eye. The vision of the healthy eye is inhibited through alteration of the eyeglass lens or cycloplegic drug use.
An eye doctor will recommend penalization as a treatment for amblyopia, a condition where poor vision is present in just one eye. When the therapy is employed, the brain takes the image of the weak eye. The expected result is a stronger vision in the previously unhealthy eye. Penalization is mainly conducted as a substitute for patching.
Types
- Atropine penalization
- Optical penalization
Before the Procedure
Atropine penalization is recommended for children aged 7 years and below. Patients are first allowed to choose a different treatment option such as patching. The caregiver then receives an information sheet that outlines the treatment details such as the value of the procedure, possible complications, and necessary follow-ups. Caregivers ought to disclose all the medications and supplements a child is taking.
The doctor also takes specific baseline measurements such as visual acuity test, ophthalmoscopy of the fundus and strabismus examination.
Procedure
Atropine penalization
One drop of 1% atropine is administered daily to the properly-functioning eye so that it is unable to focus correctly. This treatment provides an appropriate blur to make the child use their amblyopic eye. This treatment has been proven to be as efficient as patching in treating mild to moderate amblyopia.
If the child has glasses, the application of translucent tape or a Bangerter foil to the spectacle lens can be tried. Proper utilization of spectacle borne devices must be closely monitored.
Optical penalization
Optical penalization involves prescribing additional lenses to the visually correct eye to force the amblyopic eye to focus targets at a distance. It is recommended for children who do not tolerate patching or administration of atropine.
Risks & Complications
The patient faces the risk of occlusion amblyopia and systemic absorption. S/he could also suffer side effects of administered drugs such as:
- Facial flushing
- Allergies
- Irritation
- Fever and light sensitivity
- Blurred vision
- Skin dryness
- Eye pain upon application of drops
- Eyelid swelling
- Inflammation of the eye
- Decreased tearing
- Fast heart rate
- Dry mouth and throat
Atropine therapy should be carefully used when handling patients with a high likelihood of suffering from occlusion amblyopia.
Aftercare & Recovery
While vision improvement is fast for patients who have undergone patching, it is equally good after six months of penalization.
Regular follow up of patients whose amblyopia is being treated with cycloplegic drugs is essential, to prevent reverse amblyopia in the previously preferred eye.
Outcome
Atropine penalization has a success rate of above 80%. The procedure has enhancing benefits and does not fully interfere with binocular vision.
However, there is still a risk of a reverse of the amblyopia with penalization. For this reason, it is not usually used as the first treatment option by a majority of ophthalmologists.
