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Rationale Pupillometry can be used to characterize autonomic drug effects. Objective This study was conducted to determine the autonomic effects of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy), administered alone and after pretreatment with reboxetine, duloxetine, clonidine, carvedilol, and doxazosin, on pupillary function. Methods Infrared pupillometry was performed in five placebo-controlled randomized studies. Each study included 16 healthy subjects (eight men, eight women) who received placebo–MDMA (125 mg), placebo–placebo, pretreatment–placebo, or pretreatment–MDMA using a crossover design. Results MDMA produced mydriasis, prolonged the latency, reduced the response to light, and shortened the recovery time. The impaired reflex response was associated with subjective, cardiostimulant, and hyperthermic drug effects and returned to normal within 6 h after MDMA administration when plasma MDMA levels were still high. Mydriasis was associated with changes in plasma MDMA concentration over time and longer-lasting. Both reboxetine and duloxetine interacted with the effects of MDMA on pupillary function. Clonidine did not significantly reduce the mydriatic effects of MDMA, although it produced miosis when administered alone. Carvedilol and doxazosin did not alter the effects of MDMA on pupillary function. Conclusions The MDMA-induced prolongation of the latency to and reduction of light-induced miosis indicate indirect central parasympathetic inhibition, and the faster recovery time reflects an increased sympathomimetic action. Both norepinephrine and serotonin mediate the effects of MDMA on pupillary function. Although mydriasis is lasting and mirrors the plasma concentration–time curve of MDMA, the impairment in the reaction to light is associated with the subjective and other autonomic effects of MDMA and exhibits acute tolerance.

To describe methods for performing laser-assisted cataract surgery in small pupils. Iris retractors or a Malyugin Ring (Microsurgical Technology, Redmond, WA) were used for mechanical pupil dilation before laser capsulotomy and lens fragmentation. The laser treatment can be performed with or without use of ophthalmic viscosurgical devices (OVD). In 73 eyes with small pupils, laser treatment was possible after mechanical dilation device installation. With and without an OVD, no flattening of the anterior chamber or other complications occurred during re-docking, laser treatment, or the manual part of the operation. Small adhesions of the anterior capsulotomy were more frequent when the anterior chamber was still filled with the OVD and did not occur when the OVD was removed. A small, poorly dilating pupil constitutes a major challenge in cataract surgery, particularly when performing capsulorhexis. Femtosecond laser treatment can be employed with considerable benefit for the patient, even in these difficult cases.

ABSTRACTPURPOSE: Aspheric intraocular lenses (IOLs) are designed to correct spherical aberration in Pseudophakie eyes. We predict the benefit from correcting spherical aberration based on simulations and aberrometry of Pseudophakie eyes implanted with spherical IOLs.METHODS: Ray tracing was performed through a model eye with an equi-biconvex spherical IOL and with a spherical aberration-correcting aspheric IOL. The IOLs were increasingly tilted and/or displaced, and the resulting transverse aberrations of 169 rays were transformed into Zernike coefficients for different pupil sizes. The benefit from correcting spherical aberration at individual mesopic pupils was investigated by canceling C? in the sets of Zernike coefficients for 41 eyes implanted with a spherical IOL.RESULTS: Both the model eye and the real eye data predict that age-related miosis reduces spherical aberration in the eye implanted with a spherical IOL to approximately 1/3 of the spherical aberration at a 6-mm pupil. A reduction of similar magnitude occurs when spherical aberration -induced non-pa raxia I defocus is corrected by a spectacle lens. For natural mesopic pupils, canceling the Zernike C? coefficient improved the objective image quality at a rate similar to changing defocus by 0.05 diopters. Average decentration and tilt levels diminish the lead of aspheric IOLs over spherical IOLs, depending on the direction of decentration.CONCLUSIONS: The benefit from correcting spherical aberration in a Pseudophakie eye is limited for some or all of the following reasons: wearing glasses, age-related miosis, tilt and decentration of IOL, small contribution of spherical aberration to all aberrations, and intersubject variability. [J Refract Surg. 2005;21:S541-S546.]

There is a close relationship between arousal and pupil diameter, decrease in the level of arousal being accompanied by constriction of the pupil (miosis), probably reflecting the attenuation of sympathetic outflow as sedation sets in. Paradoxically, sedation induced by benzodiazepines is not accompanied by miosis. The objective of this study was to examine the hypothesis that diazepam may attenuate both the sympathetic and the opposing parasympathetic outflow to the iris, which may mask the miosis. Dapiprazole (sympatholytic) and tropicamide (parasympatholytic) were applied topically, together with the cold pressor test (CPT), to manipulate the sympathetic/parasympathetic balance. Sixteen healthy male volunteers participated in four weekly sessions according to a balanced double-blind protocol. Diazepam 10 mg (two sessions) and placebo (two sessions), associated with either 0.01% tropicamide or 0.5% dapiprazole eyedrops, were administered orally. Pupil diameter, light and darkness reflexes and pupillary sleepiness waves were recorded with infrared video pupillometry, alertness was measured by critical flicker fusion frequency (CFFF) and visual analogue scales (VAS), blood pressure and heart rate by conventional methods. CPT was applied after post-treatment testing. Data were analysed by analysis of variance, with multiple comparisons. Diazepam caused sedation (reduction in VAS alertness scores and CFFF, increase in sleepiness waves), dapiprazole had a sympatholytic and tropicamide a parasympatholytic effect on the pupil. Diazepam had no effect on pupil diameter and reflexes or their modifications by the antagonists. CPT increased pupil diameter, blood pressure and heart rate, and the increase only in systolic blood pressure was attenuated by diazepam. Diazepam-induced sedation is not accompanied by any change in either the sympathetic or parasympathetic influence on the iris.

This discussion reviews the common causes of Horner's syndrome, with emphasis on case reports from the past several years. Much of the recent literature concerns the use of apraclonidine as a diagnostic test for Horner's syndrome, possibly as an alternative for the current gold standard of cocaine eye drops. This new literature is discussed in the context of the current standards for clinical diagnosis.

Purpose To investigate the age-related changes in a myopic shift under binocular conditions (phoria myopia) in patients with intermittent exotropia (IXT). Methods Forty-five patients with IXT were studied: 21 were ≤9 years old (children), 11 were between 10 and 19 years (adolescents), and 13 were between 20 and 43 years (adults). The angle of strabismus was determined by the alternating prism cover test. The spherical refractive error was measured at 1 m using infrared video retinoscopy under monocular and binocular viewing conditions. Results The change in the spherical refractive error (ΔR) between binocular and monocular conditions was significantly larger in adults (ΔR = −1.11 ± 1.01 diopters (D), average ± standard deviation) than in children (ΔR = −0.34 ± 0.34 D; P < 0.05, analysis of variance). ΔR was significantly correlated with the angle of exotropia only in adults ( r = 0.55, P = 0.04). After strabismus surgery, ΔR decreased in adults ( n = 3). Conclusions Because a significant myopic shift under binocular conditions was detected in IXT patients older than 20 years, phoria myopia can occur after age 20 even if functional disturbances are not observed in children or adolescent IXT patients, a fact that specialists need to bear in mind when treating younger patients.

The purpose of this study was to assess the influence of pupil size and optical blur on measurements obtained with isolated-check visual evoked potential (icVEP). Two stimulus conditions of icVEP, +15 and −15% contrasts, were studied in normal subjects with normal (N), miotic (M), and dilated (D) pupils. The effects of optical blur were studied in subjects with normal pupil. Response to visual stimuli was quantified by a signal-to-noise (SNR) ratio. In 30 normal subjects, the mean age was 26.0 ± 3.4 years. Mean pupil diameters were N = 4.2 ± 0.6 mm, M = 2.7 ± 0.6 mm, and D = 7.3 ± 0.9 mm. For both +15 and −15% contrast levels, mean SNR values were reduced for dilated and constricted pupils when compared with normal pupils. Mean SNR values for optical blur with a +2 or +3 diopter lens placed over the distance correction were reduced when compared with SNR measurements obtained with best-corrected visual acuity under both +15 and −15% contrast levels. Statistical significance was found in comparisons of N versus M ( P  < 0.001) and N versus D ( P  = 0.002) for +15 and −15% contrast conditions, respectively. No statistical difference was seen for M versus D ( P  = −0.435). The effect of optical blur was statistically significant when compared to the normal pupils with best-corrected vision ( P  < 0.001). No statistically significant difference was found comparing +2 and +3 diopters lenses for optical blur testing. Visual evoked potential values are influenced by pupillary constriction and dilation, as well as optical blur. When obtaining icVEP measurements, the influence of pupil size and optical blur should be kept in mind for accurate interpretations.

The objective is to identify the pathogenesis of each autonomic manifestation in cluster headache (CH). Through a deductive statistics method (factor analysis) we analysed the type of autonomic symptoms reported by 157 CH patients. Three principal components were identified in the analysis: parasympathetic activation (lacrimation, conjunctival injection and rhinorrhoea), sympathetic defect (miosis and ptosis) and parasympathetic mediated effect (nasal congestion, eyelid oedema and forehead sweating). This work suggests that there are three different mechanisms underlying autonomic manifestations in CH.

Patients with chronic open angle glaucoma are traditionally managed by medical therapy during the early stages of the disease. Pilocarpine is a well established topical agent, but suffers troublesome sequelae, the most apparent of which is pupillary constriction. This study assesses the effect of miosis (produced by one drop of 2% pilocarpine) on the static threshold perimetry of 20 subjects with chronic open angle glaucoma and documented visual field loss, using the 30-2 program of the Humphrey field analyser. Following miosis, the Statpac mean defect deteriorated by an average of -1.49 dB compared with baseline (p = 0.004). This dB deterioration is twice that reported in studies on younger normal subjects following miosis. The decrease in mean defect showed a positive correlation with the degree of pupillary constriction, the correlation being greater in those eyes with a miosed pupil diameter of 2 mm or less. There was no significant decrease in the other Statpac global indices following miosis. A parallel study using the fellow eye of the same glaucoma patients showed a high degree of intertest variability, but no significant learning or fatigue effect. We conclude that pilocarpine-induced miosis causes a significant deterioration in visual field in a population of patients with chronic open angle glaucoma: this factor should be considered when choosing therapy for glaucoma particularly in cases where field loss approaches the permitted legal minimum for driving.