The antimuscarinic activity of optical isomers of tropicamide were compared on the isolated rabbit iris sphincter. The increasing concentrations of both the (--)- and (+)-isomer shifted the dose-response curve of carbachol to the right in a parallel fashion. The competitive reversible muscarinic blocking effects of both isomers were confirmed by pA2 plots. The pA2 values from the nonpigmented i...

PURPOSE The aim of this study was to investigate the time-course of changes in choroidal thickness (ChT) following complete mydriasis induced by compound tropicamide. METHODS ChT was measured by OCT with the enhanced-depth imaging technique (Spectralis HRA+OCT, Heidelberg Engineering, Germany) at nine locations of the fundus: subfoveal ChT (SFChT) and ChT at 1 mm and 3 mm from the fovea in fo...

OBJECTIVE The pharmacological response to drugs that act on the cholinergic system of the iris has been used to predict deficits in central cholinergic functioning due to diseases such as Alzheimer's disease, yet correlations between central and peripheral responses have not been properly studied. This study assessed the effect of normal aging on (1) the tropicamide-induced increase in pupil di...

To the Editor: We have previously shown that the Orbscan (Bausch & Lomb, Rochester, New York) was unable to map the corneal surfaces in eyes with shallow anterior chambers , displaying a clonic quad map, and that the clonic quad map disappeared after YAG iridotomy. 1 We now report a case of clonic quad map with Orbscan in a patient with shallow anterior chambers that resolved after pupillary di...

PURPOSE This study compares retinoscopy in infants using a near noncycloplegic technique, cycloplegia with tropicamide 1%, and cycloplegia with cyclopentolate 1%. The study sample included 29 healthy, nonstrabismic infants 4 to 7 months of age (mean 5.71 months). METHODS Each study subject was examined at two separate visits an average of 2 weeks apart (mean [+/-SD] 14 +/- 9 days). The examin...

A comparative study in healthy subjects and diabetic patients of the mydriatic response to topical tropicamide 0.5% with and without added phenylephrine 10% is reported. The findings indicate that diabetic pupils respond relatively poorly to tropicamide alone but adequately and completely to the drug combination. The pupils of diabetic patients whose eyes had previously received laser treatment...

The objective of this study was to determine the effects of topical 0.5% tropicamide, 1% atropine sulphate and 10% phenylephrine hydrochloride ophthalmic solutions on intraocular pressure (IOP) and horizontal pupil diameter (HPD) in the dog during the first hour after treatment. Forty clinically and ophthalmologically normal canine patients (between the ages of 2 and 6 years) of varying breed a...

PURPOSE To evaluate the effect of cycloplegic mydriasis with 1% cyclopentolate and 1% tropicamide on the intraocular pressure (IOP) and refractive status of children for cycloplegic refraction and compare the [OP and refractive changes between hyperopic and myopic groups. METHODS This study was designed as a retrospective cohort study. Ninety one children received cycloplegic mydriasis. The I...

Dilation of pupil has been a major component diagnostic eye examination inOptometric practice. Although mydriatic agents are used in clinical procedures, thereis no satisfactory explanation for the preference one over another. This studycompared dilating effect three different on dark irides ofninety healthy subjects; comprising 48 males and 42 females aged 16-30 (mean age18.77±0.52) years divi...