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Proparacaine-Induced Mydriasis During Strabismus Surgery
Brijesh Takkar1, Pradeep Sharma1, Nripen Gaur1
1a Dr. R. P. Centre for Ophthalmic Sciences , All India Institute of Medical Sciences , New Delhi , India.
Seminars in Ophthalmology
|December 15, 2016
Summary
Proparacaine hydrochloride (PH) causes pupil dilation and horizontal skewing in children undergoing strabismus surgery. Surgeons should account for this mydriatic effect during eye alignment assessment post-operation.
Area of Science:
- Ophthalmology
- Pediatric Surgery
- Anesthesiology
Background:
- Strabismus surgery in children often requires general anesthesia.
- Pupil dilation is crucial for surgical assessment but can be affected by anesthetic agents.
- Proparacaine hydrochloride (PH) is a topical anesthetic commonly used in ophthalmology.
Purpose of the Study:
- To evaluate the mydriatic effect of proparacaine hydrochloride (PH) in pediatric patients undergoing strabismus surgery.
- To assess the impact of PH on pupil diameter (PD) and pupil מרכז (PC) during strabismus surgery under general anesthesia (GA).
Main Methods:
- Pilot, prospective, non-randomized, self-controlled interventional study.
- Nine pediatric patients with esotropia or exotropia undergoing horizontal muscle surgery under GA.
- PH was instilled in one or both eyes; PD and PC changes were measured.
Main Results:
- Proparacaine hydrochloride (PH) demonstrated a significant mydriatic effect, increasing pupil diameter (PD) and pupil מרכז (PC) in study eyes.
- Dilated pupils showed horizontal skewing towards the operated muscle.
- Control eyes showed no changes in PD or PC.
Conclusions:
- Proparacaine hydrochloride (PH) possesses an intrinsic mydriatic effect, penetrating the sclera.
- The mydriatic effect can cause skewed pupil dilation, influencing intraoperative assessment.
- Surgeons must consider PH's effect on pupil alignment during strabismus surgery.
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