Separate and additive mydriatic effects of lidocaine hydrochloride, phenylephrine, and cyclopentolate after intracameral injection.
Author(s): Lundberg B, Behndig A
Affiliation(s): Department of Clinical Science/Ophthalmology, Umea University Hospital, Umea, Sweden. email@example.com
Publication date & source: 2008-02, J Cataract Refract Surg., 34(2):280-3.
Publication type: Comparative Study; Randomized Controlled Trial
PURPOSE: To assess the separate mydriatic effect of lidocaine hydrochloride (Xylocaine), cyclopentolate, and phenylephrine after intracameral injection and evaluate whether intracameral Xylocaine and phenylephrine without cyclopentolate provide sufficient pupil dilation for cataract surgery. SETTING: Department of Clinical Science/Ophthalmology, Umea University Hospital, Umea, Sweden. METHODS: This prospective randomized double-masked study included 56 patients with age-related cataract scheduled for unilateral phacoemulsification. In 16 patients, Xylocaine 1%, phenylephrine 1.5%, and cyclopentolate 0.1% were injected one after the other. Phenylephrine and cyclopentolate were randomized to switch in order, creating 2 study groups. An additional 40 patients were randomized to receive intracameral Xylocaine 1%, phenylephrine 1.5%, and cyclopentolate 0.1% or intracameral Xylocaine 1% and phenylephrine 1.5% only. RESULTS: Xylocaine alone caused significant pupil dilation (mean 4.9 +/- 0.6 mm). In the group in which cyclopentolate was injected next, the pupil size increased 1.3 +/- 0.6 mm (P<.001). When phenylephrine was added, the pupil increased an additional 0.7 +/- 0.4 mm (P = .003). In the second group, in which phenylephrine was the second injection, the pupil size increased 2.1 +/- 0.5 mm (P<.001). When cyclopentolate was added, no significant change in size occurred. No statistically significant differences in pupil size were observed between the 40 patients who were given intracameral mydriatics with or without cyclopentolate. CONCLUSIONS: Xylocaine plus phenylephrine injected intracamerally gave adequate intraoperative pupil dilation in routine phacoemulsification surgery. Cyclopentolate administrated intracamerally had no immediate additive mydriatic effect to intracameral Xylocaine combined with phenylephrine.