As a new grad, you should feel like you have a well-rounded education and are prepared for anything that walks through your door.
However, there are always going to be a few things that make you a bit uncomfortable. I often hear from my colleagues that don't deal with binocular vision issues on a daily basis that "strabismic patients make them nervous."
This review will help remind you of the most important aspects to identify in your patients with strabismus so that you can discuss appropriate treatment options with your patient, even if you don't provide them.
1. Case History
This is by far the most important aspect of learning about the patient and the potential etiology of the strabismus.
You want to ask the following questions:
- Onset – this is a really important question; if it is new onset in an adult, you will want to rule out a systemic etiology.
- Presence of diplopia, ‘tired eyes’ or other symptoms that might tip you off that they have an issue.
- Systemic health (hypertension, diabetes, etc…)
- Family history
- Any prior treatment
2. Visual Acuity
Test this at distance and near.
If amblyopia is also present, remember to test both single letter acuity vs. whole line.
3. Cover Test
This determines the type, magnitude and constancy of the deviation.
Start with unilateral cover test then move to alternating. If you have the equipment you can measure it with a prism bar... if not, make an estimation.
4. Level of Stereopsis
If you have the proper equipment, test for level of stereopsis as this will give you a good indication of how your patient is functioning.
This includes Worth 4 Dot for presence of flat fusion, Wirt Circles (local stereo) and RDS (global stereo).
5. Complete your regular "eye doctor stuff"
This includes a refraction to achieve the best corrected visual acuity. Additionally, a slit lamp exam and dilation should be completed to rule out any pathological etiology.
With this information you'll be able to discuss with your patients what the treatment options are and which is best suited for them.
Treatment Options Can Include:
1) Compensatory prism
For example: patients with divergence insufficiency or vertical deviations often find a lot of relief with a little bit of prism in their glasses. Determining the amount of prism is a matter of the size of the deviation, the patient's fusional ranges as well as their sensitivity.
2) Referral for vision therapy or surgery (if warranted)
Make sure you know which of your colleagues perform vision therapy so you can make the appropriate referral!
Sometimes if the patient is happy and is functioning just fine, you can choose to just monitor them.
Want more tips on binocular vision disorders? Check out our downloadable study guide!