Optometric Management Tip # 223   -   Wednesday, April 26, 2006
More Thoughts on Pupil Dilation

Last week I covered an idea to make pupil dilation more efficient in the office, and this week I’ll offer some more tips and ideas on that topic.

Delegate refraction

I recently acquired two computerized refraction systems in my practice, which allows technicians to assist with subjective refraction testing. While most doctors utilize these instruments to save time spent on gathering refractive data, there is an additional benefit with pupil dilation. Once the subjective refraction is done, the technician can check anterior chamber angles with a slit lamp and fully dilate the patient with tropicamide. When the doctor sees the patient, he is already dilated, saving the need to instill drops and see the patient back a second time. The distance subjective refraction can even be fine tuned or confirmed by the doctor in the dilated state.

Pre-dilate older patients

Some doctors have their technicians pre-dilate their patients that are 55 years of age or older, using a drug with tropicamide. The doctor does the refraction with the eye dilated and somewhat cyclopleged, but the reasoning is that patients in this age group have little accommodation and the refractive result will be the same.

Instill drops upon entering

This technique works well in conjunction with last week’s tip when the eyes are pre-dilated with phenylephrine 2.5%. With the phenylephrine already working, the doctor may add 1 drop of tropicamide to each eye immediately after greeting the patient during the doctor part of the visit. Then the doctor does his or her usual tests: reviews case history, refraction, slit lamp, discusses some of the findings and recommendations, and finally does the fundus exam. At this point, the phenylephrine has had about 40 minutes to work and the tropicamide might have had close to 15 minutes. This technique can provide a fully dilated pupil in many patients and allow a peripheral retinal exam with a BIO.

Choice of drugs

We have a need for several different mydriatic drops for various applications and types of patients. Some patients, such as those with dark pigmentation and diabetics, are harder to dilate and may require a stronger drug concentration. In some cases we want a stronger cycloplegic affect for checking true refractive status or for pain relief. In some cases we want a fast acting drug that has a short acting cycloplegic effect, so our patients can return to work with little inconvenience. Generally, we use phenylephrine (Neosynephrine) 2.5%, tropicamide (Mydriacyl) .5% and 1%, and cyclopentolate (Cyclogyl) .5% and homatropine 5%.

For routine fundus evaluations Paremyd is an excellent choice because it has only .25% tropicamide – less than any other formulation. This low dose is sufficient for good pupil dilation, but it has reduced cycloplegic action and quicker recovery time. Paremyd is a combination drug: tropicamide along with hydroxyamphetamine (which used to be sold under the brand name Paredrine), so there is a cross action mydriasis. Hydroxyamphatmine does not cycloplege and is similar to phenylephrine. Paremyd was off the market for awhile – but is now available again from Akorn.

Best wishes for continued success,

Neil B. Gailmard, OD, MBA, FAAO
Chief Optometric Editor, Optometric Management