Pupil dilation using drops vs gel: a comparative study

Abstract

PurposeTo compare the efficacy in pupil dilation and degree of discomfort between topical instillation of mydriatic drops and gel.MethodsThe study included 60 patients with no previous ocular history of trauma and surgery. One eye was dilated with two drops (tropicamide 0.5% and phenylephrine 10%), and the other with one drop of gel (tropicamide 0.5%+phenylephrine 5%). Pupil size was measured by a Colvard pupillometer at baseline and 5, 15, 30, and 45 min following instillation. Pain upon instillation was measured by visual analog scale (VAS).ResultsThere was no difference in pupil size at baseline. Use of the gel achieved greater mydriasis than drops (P=0.01), and was also associated with lower pain scores (P=0.003). In diabetic patients, pupil size was smaller at baseline and following instillation of drops and gel. Use of the gel achieved an even greater degree of pupil dilation in this subset of patients than drops (P=0.019).ConclusionsGel formulation achieved significantly greater pupil dilation than drops, despite a lower concentration of phenylephrine, and was also associated with significantly lower patient discomfort. This study is the first report of improved mydriatic efficacy in diabetic patients.

A Deep Learning Approach to Denoise Optical Coherence Tomography Images of the Optic Nerve Head

“…Moreover, pupillary dilation may be needed especially in subjects with small pupil sizes to obtain acceptable quality B-scans 12,90 , which is highly crucial in the monitoring of glaucoma 90 . Pupillary dilation is also time consuming and may cause patient discomfort 91 . It is plausible that the proposed framework, when extended, could be a solution to the afore-mentioned factors that limit image quality, avoiding the need for any additional clinical procedure.…”

Acute Exacerbation of Fever Following Administration of Tropicamide and Phenylephrine Ophthalmic Solution: A Case Report

“…Generally, drug-induced fever classified as a hypersensitivity reaction (the most prominent category) develops 3–14 days after the start of administration, with most occurring after 7–10 days [ 17 ]. In the present case, the onset of fever was rapid (within 15 min after administration) and coincided with the time at which both tropicamide and phenylephrine normally induce maximum pupillary dilatation (15–45 min) [ 18 ]. As there were no other symptoms (i.e.…”

High‐dose phenylephrine increases meningeal blood flow through TRPV1 receptor activation and release of calcitonin gene‐related peptide

“…TRPV1 receptor channels are expressed in a major proportion of nociceptive afferents, constituting the crucial molecular transduction channels for a variety of noxious stimuli associated with painful tissue lesions, inflammation and heat (Holzer, ; Rosenbaum & Simon, ; White, Urban, & Nagy, ).The unexpected finding that high‐dose phenylephrine is obviously also an agonist at TRPV1 receptors, including human TRPV1, cannot easily be explained by its molecular structure, although it has some similarity with the aromatic end‐structure of capsaicin. Phenylephrine at high concentrations is routinely used as a mydriatic agent and for the treatment of nasal congestions (https://medlineplus.gov/druginfo/meds/a616049.html) frequently causing transient local burning or stinging pain sensations (Moisseiev et al, ). We now offer a reasonable pathophysiological explanation for these effects, which are reminiscent of mild capsaicin‐evoked pain.…”

“…Phenylephrine at high doses (1%-5%, i.e. 60-300 mM) is locally used as a mydriatic agent, for example in the treatment of glaucoma (McAuliffe-Curtin & Buckley, 1989;Moisseiev et al, 2015). As adverse side-effects of this treatment increases in blood pressure and pulse rate (Chin, Law, & Chin, 1994) and bronchoconstriction in premature infants (Kim, Choi, & Kwak, 2015) have been reported.…”