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Physiological adaptation of the eye to the visual perception of near objects consists of the "near triad": convergence, accommodation, and pupil miosis. Normally, these tend to revert when one stops fixating on a near object. Spasm of the near reflex (SNR) is a pathological phenomenon, which manifests itself by the persistence of the above-mentioned adjustments, which prevents the eye from returning to its relaxed state. In this narrative review, we aim to summarize the etiology, diagnostics, treatment, and prevention of SNR. The literature review was performed by searching online databases. The clinical presentation of SNR is diverse; it presents as isolated accommodative spasm more frequently than impairment of all three components of the near triad. Patients usually present with fluctuations in visual acuity, blurred vision, diplopia, and asthenopia. The etiology is not fully understood. Potential causes include neuroanatomic, organic, and psychogenic disorders. The diagnosis is clinical, based on the constellation of symptoms and assessment of the near triad. The diagnostic golden standard is a cycloplegic examination of refraction, preferably using cyclopentolate hydrochloride (1%, 0.5%, or 0.1% solution). The first-line treatment requires the administration of a cycloplegic drug in combination with plus lenses, flipper lenses, optical fogging, or miotics. For secondary cases, causal treatment should be implemented. Prevention of SNR should be based on eliminating modifiable risk factors. We propose including screening for SNR symptoms in every ophthalmic examination, especially among patients with psychogenic or neural disorders, after brain trauma, or young adults spending much time in front of computer screens., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: To compile real-time data on the preferred mydriasis practice patterns for retinopathy of prematurity (ROP) screening in Europe., Methods: A cross-sectional online survey was conducted from December 2022 to January 2023, using a self-report online questionnaire which was distributed via email to the members of the European Pediatric Ophthalmological Society and the Greek National ROP Task Force. A six-week period of recruitment was determined, and a reminder email was sent after two weeks. Descriptive statistics were used to explore the data, which was summarized with frequencies and percentages., Results: Sixty-six responses were recorded (response rate: 29.5%), representing practices in 55 Neonatal Intensive Care Units from 21 European countries. In 94.5%, the applied mydriatic regimen consists of phenylephrine with at least one muscarinic antagonist, either tropicamide or cyclopentolate. The concentration of phenylephrine ranges from 0.5% to 5%, of tropicamide from 0.25% to 1%, and of cyclopentolate from 0.2% to 1%. The most commonly used regimen (43.6%) contains phenylephrine 2.5% and tropicamide 0.5%, administered either combined or separately. About 54.5% of the reported mydriatic solutions are non-commercial, in-house preparations. Systemic adverse events, including oxygen desaturation, bradycardia and cardiopulmonary arrest were reported in 14.5%., Conclusion: There is considerable heterogeneity in the applied mydriatic regimens for ROP screening in Europe, reflecting the absence of universal guidelines. The wide use of in-house preparations underlines the gap in the pharmaceutical industry. Concern should be raised against the wide use of undiluted commercial drugs, that reach adult dose, in the fragile population of preterm infants., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: To estimate the effect of atropine eyedrops at different concentrations for myopia control in children., Methods: We conducted a Bayesian random-effects network meta-analysis based on randomized controlled trials (RCT). Primary outcomes include changes in spherical equivalent error (SER) and changes in axial length (AL), mean difference (MD) together with 95% credible interval (CrI) were used to evaluate the efficacy., Results: 28 RCTs (6608 children) were included in this review. Comparing ten atropine eyedrops (0.0025%, 0.005%, 0.01%, 0.02%, 0.025%, 0.05%, 0.1%, 0.25%, 0.5% and 1% concentrations) with the placebo, the MDs and 95%CrIs of changes in SER are -0.006 (-0.269, 0.256) D, 0.216 (-0.078, 0.508) D, 0.146 (0.094, 0.199) D, 0.167 (0.039, 0.297) D, 0.201 (0.064, 0.341) D, 0.344 (0.251, 0.440) D, 0.255 (0.114, 0.396) D, 0.296 (0.140, 0.452) D, 0.331 (0.215, 0.447) D, and 0.286 (0.195, 0.337) D, respectively. The MDs and 95%CrIs of changes in AL are -0.048 (-0.182, 0.085) mm, -0.078 (-0.222, 0.066) mm, -0.095 (-0.130, -0.060) mm, -0.096 (-0.183, -0.009) mm, -0.083 (-0.164, -0.004) mm, -0.114 (-0.176, -0.056) mm, -0.134 (-0.198, -0.032) mm, -0.174 (-0.315, -0.061) mm, -0.184 (-0.291, -0.073) mm, and -0.171 (-0.203, -0.097) mm, respectively.Whether evaluated by SER or AL, 1% concentration ranks first in efficacy, but the risk of photophobia is 17 times higher than 0.01% concentration., Conclusions: 0.01% or higher concentration atropine eyedrops are effective for myopia control, while 0.0025% and 0.005% concentrations may not. As the concentration increases, the effect tends to increase, 1% concentration may have the strongest effect., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: This study investigates the relationship between pupil size during biometry examinations and the chord mu value in candidates for cataract surgery., Methods: Retrospective analysis of ocular biometry measurements was performed on consecutive cataract surgery candidates above 50 years of age, examined between 2018 and 2020 at a single tertiary referral center. Statistical analysis assessed the association between pupil size and the chord mu value. The population was categorized into groups based on pupil size, and an analysis was conducted on the barycenter positions of the iris and pupil center for each group., Results: The analysis included 2877 patients. A weak positive correlation was observed between the chord mu value and pupil size using Pearson's test ( r  = 0.160, p  < 0.01). Group stratification by pupil size indicated temporal and inferior shifts in pupil center barycenter as pupil size increased, reflecting asymmetrical pupil dilation during mydriasis. A moderate positive correlation between the chord mu value and chord alpha value was identified (Pearson's test, r  = 0.641, p  < 0.01). As expected, no correlation was found between chord alpha value and pupil size., Conclusions: Chord mu values were higher in patients with mydriatic pupils, likely due to asymmetric pupil dilation and center displacement. Evaluating chord mu values requires considering pupil status and conducting biometry under standardized lighting to prevent misinterpretation caused by pharmacological dilation. This caution is crucial to avoid erroneously excluding eligible patients from multifocal IOL implants. Alternatively, the chord alpha value could serve as a more appropriate alternative in such scenarios., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: To evaluate changes in ocular motility deviation with cycloplegic eye drop examination compared to the prism adaptation test in patients with strabismus., Methods: The medical charts were reviewed of all patients who underwent primary strabismus surgery in our center from December 2013 to July 2015. Data collected included demographics, medical history, and findings on pre-operative ophthalmic/orthoptic examination. Ocular motility deviation was measured before instillation of cycloplegic eye drops, immediately after maximal dilation (end point), and 10 and 20 min later. Prism adaptation test readings were taken at baseline, immediately after prism removal (end point), and 10 and 20 min later., Results: A total of 43 patients had complete pre- and post-operative evaluations. Our analysis focused only on the exotropic patients (n = 33). On cycloplegics, there was no significant difference in ocular motility deviation between baseline and end point for distance and near (p = 0.584, p = 0.468, respectively). On prism adaptation test, comparison of ocular motility deviation between baseline and end point was statistically significant for distance and near (p = 0.002, p = 0.001, respectively). Changes remained significant 10 min after the end point for near (p = 0.011). Comparison at the end points between the tests revealed statistical significance for distance and near, favoring the prism adaptation test (p = 0.001 and p < 0.001, respectively). This significance was maintained even after 10 min for near (p = 0.036)., Conclusion: The prism adaptation test is preferred over cycloplegic eye drops for the evaluation of maximal reserve of distance/near motility before surgical correction of exotropia.

Purpose: To evaluate the effect of corneal crosslinking (CXL) with ultraviolet A (UVA) irradiation on pupil response to tropicamide 0.5% instillation., Methods: This prospective interventional study enrolled 17 patients (19 eyes) with progressive keratoconus who underwent CXL with UVA irradiation. Central corneal thickness (CCT) was evaluated with the use of anterior segment optical coherence tomography (Visante OCT 3.0). Pupil diameter was measured with the use of Colvard infrared pupillometer before the instillation of tropicamide 0.5% and after the instillation of tropicamide every 5 minutes for total duration of 30 minutes. Corneal epithelial integrity was examined with the use of fluorescein dye staining. Measurements were performed 1 day preoperatively and 1 month postoperatively, with emphasis on simulating the same light conditions regarding the pupil measurements., Results: No intraoperative or postoperative complications were observed in any of the patients. Mean CCT decreased significantly (p&lt;0.001) 1 month postoperatively. Mean postoperative pupil size did not change significantly at any time point compared to the mean preoperative measurements., Conclusions: The CXL procedure seems not to impair effectiveness of topical drugs, using pupil size measurements after tropicamide 0.5% instillation.

Purpose: To evaluate the influence of the extent of the interoperative period on binocular vision function in patients after consecutive bilateral cataract extractions and intraocular lens implantation., Methods: The study included patients operated due to bilateral cataract. Presence of asthenopic symptoms, distance and near squint angle, fusional amplitudes, stereopsis, and convergence were evaluated. Preoperative, interoperative, and postoperative differences in best-corrected visual acuity between eyes were also noted. Multivariate analysis was conducted in order to establish the relation between the interoperative period and binocular status., Results: The study included 104 patients (74 female, 30 male, mean age 69.9 years, range 32-88). Mean interoperative period was 20.3 ± 12.9 months, range 1.5-47.7. Prolongation of the interoperative interval had a significant negative impact on stereopsis measured by TNO (R2 = 0.215, p = 0.001) and Randot (R2 = 0.179, p = 0.001) stereotests, as well as for near point of convergence (R2 = 0.09, p = 0.002). It was also related, but not independently, to reduction in fusional amplitudes, mainly for distance (R2 = 0.18, p = 0.001 for divergence and R2 = 0.12, p = 0.001 for convergence). Asthenopic symptoms were reported by 17 (16.3%) patients. The incidence of exophoria was significantly (p = 0.002) higher in patients with an interoperative interval longer than 24 months., Conclusions: The length of the interoperative period influences the status of binocular vision in patients after bilateral cataract extraction. It is also connected with an increased number of patients with asthenopic symptoms and exophoria.

Purpose: To determine if there are any differences between eye parameters measured by the IOLMaster (Carl Zeiss Meditec AG, Jena, Germany) biometer before and after dilating the pupil. The effect of those changes on intraocular lens (IOL) power calculation is also analyzed., Methods: A prospective observational study was carried out including 107 right eyes of 107 patients with cataract and no other ocular morbidity. An IOLMaster baseline measurement included axial length (AL), mean keratometry (K), and anterior chamber depth (ACD) (corneal epithelium to lens). A second measurement was taken 45 minutes after instillation of topical tropicamide and phenylephrine. Biometric variation was analyzed and prediction for IOL power based on the Haigis and the Sanders/Retzlaff/Kraff Theoretical (SRK/T) formulas was calculated for both measurements., Results: The ACD increased significantly after dilation (+0.12 ± 0.12 mm; p&lt;0.01). The AL and K variation was not significant: +0.00 ± 0.02 mm (p = 0.62) and +0.01 ± 0.22 D (p = 0.57), respectively. Pupil dilation did not affect IOL power calculation based on SRK/T formula either targeting emmetropia (-0.02 ± 0.26, p = 0.30) or the lowest myopic residual refraction (-0.03 ± 0.34, p = 0.30). However, using the Haigis formula significantly changed calculations for emmetropia (0.07 ± 0.34, p = 0.03) and for the lowest myopic refraction (0.10 ± 0.40, p = 0.01)., Conclusions: Pupil pharmacologic dilation produces a significant increase in ACD when measured by the IOLMaster. This change results in a different IOL power prediction according to the Haigis formula, which calculates the effective lens position taking into account the ACD.

Purpose: Retinopathy of prematurity (ROP) is a leading cause of visual loss in infancy that is largely preventable with careful screening. We report the safety and efficacy of the use of phenylephrine 2.5% and cyclopentolate 0.5% eyedrops instilled 3 times 5 minutes apart in ROP screening., Methods: A total of 1246 ROP screening eye examinations were carried out by the same pediatric ophthalmologist between February 2011 and May 2013. Outcome measures were successful mydriasis (defined as achieving a full screening examination) and any intraprocedural systemic complications (defined as any respiratory, cardiac, or other clinical deterioration severe enough to result in screening abandonment)., Results: Of 1246 eyes, 1234 (98.8%) achieved successful dilation to enable complete screening. A fourth application was successful in the remaining 1.2%. No respiratory or cardiac arrest or any other intraprocedural event requiring cessation of screening was encountered during any of the examinations. No retinal bleeding or other intraocular complication occurred., Conclusions: This is the largest cohort studying the effectiveness and safety of a mydriatic regimen for ROP screening. We have found the combination of phenylephrine 2.5% with cyclopentolate 0.5% to be efficacious and well-tolerated. The absence of any severe intraprocedural complications may be related to reduced indentation time and stress in the infant facilitated by effective pupil dilation.

Purpose: To verify the efficacy to obtain mydriasis and cardiovascular safety of Mydriasert (ophthalmic insert containing tropicamide and phenylephrine) in diabetic and nondiabetic patients undergoing retinal angiography by comparing it with usually administered eyedrops (tropicamide 1% and phenylephrine 10%)., Methods: This was a prospective randomized study. A total of 154 eyes of 77 patients were randomly divided into 2 groups: group 1 consisted of 78 eyes, group 2 consisted of 76 eyes, and the patients were monitored for pupillary dilation, blood pressure, heart rate, and possible adverse effects at 0, 20, 40, 60, and 90 minutes., Results: No severe adverse effects were observed in either group. In the entire sample studied, the mean pupillary diameter was greater in the eyedrops group after 20 and 40 minutes, while mydriasis was similar in the 2 groups after 60 minutes. The diabetic patients treated with Mydriasert had less mydriasis than those treated with eyedrops after 20 and 40 minutes, and diabetic patients showed less mydriasis than the nondiabetic patients after 60 and 90 minutes. There was no significant between-group difference in mean heart rate or systolic and diastolic blood pressure at any of the time points., Conclusions: Mydriasert assures an adequate degree of mydriasis for retinal angiography in both diabetic and nondiabetic patients. There are no differences in efficacy or safety between the insert and the usually administered eyedrops, but the low total drug dose administered with the insert reduces the risk of cardiovascular side effects.

Purpose: To determine the possible influence of pupil dilation on intraocular lens (IOL) power predictions made using optical biometry with Lenstar LS 900® (Haag-Streit AG, Koeniz, Switzerland)., Methods: A total of 72 eyes of 72 patients scheduled to undergo cataract surgery were prospectively examined using the optical low-coherence reflectometry (OLCR) optical biometer before and after pupil dilation with tropicamide 1%. The measurements made were axial length, central corneal thickness, anterior chamber depth (ACD), lens thickness, mean keratometry, corneal diameter (CD), and pupil diameter. Holladay II and SRK/T formulas were used to calculate IOL power. Agreement between the 2 measurement modes (with and without dilation) was assessed by calculating intraclass correlation coefficients (ICC) and constructing Bland-Altman plots., Results: The mean age of the patients was 74.71 ± 7.53 years (range 56-90). Among the variables determined, only ACD varied significantly according to pupil dilation (p<0.001). The ICC data revealed excellent intraobserver correlation between measurements made with and without dilation, except for CD. The IOL power predictions were unmodified., Conclusions: The use of pupil dilation does not seem to influence measurements and IOL predictions made using this OLCR optical biometer.

Purpose: To investigate the reliability of a biometric iris recognition system for personal authentication after cataract surgery or iatrogenic pupil dilation., Methods: This was a prospective, nonrandomized, single-center, cohort study for evaluating the performance of an iris recognition system 2-24 hours after phacoemulsification and intraocular lens implantation (group 1) and before and after iatrogenic pupil dilation (group 2)., Results: Of the 173 eyes that could be enrolled before cataract surgery, 164 (94.8%) were easily recognized postoperatively, whereas in 9 (5.2%) this was not possible. However, these 9 eyes could be reenrolled and afterwards recognized successfully. In group 2, of a total of 184 eyes that were enrolled in miosis, a total of 22 (11.9%) could not be recognized in mydriasis and therefore needed reenrollment. No single case of false-positive acceptance occurred in either group., Conclusions: The results of this trial indicate that standard cataract surgery seems not to be a limiting factor for iris recognition in the large majority of cases. Some patients (5.2% in this study) might need "reenrollment" after cataract surgery. Iris recognition was primarily successful in eyes with medically dilated pupils in nearly 9 out of 10 eyes. No single case of false-positive acceptance occurred in either group in this trial. It seems therefore that iris recognition is a valid biometric method in the majority of cases after cataract surgery or after pupil dilation.

Purpose: To determine the change in pattern electroretinogram (PERG) amplitude during the ibopamine test in patients with ocular hypertension (OHT)., Methods: A total of 32 eyes (16 patients) with OHT (8 male, 8 female), mean age 54.19 years (range 22-76 years), mean baseline intraocular pressure (IOP) 23 ± 2 mm Hg, received a PERG assessment in both eyes every 5 minutes from baseline to 60 minutes. All the patients were pretreated by thymoxamine eyedrops to avoid the mydriatic effect of ibopamine. All the data were evaluated by descriptive statistics and paired t test. The results were considered with a significance level of p<0.05., Results: All the patients enrolled matched the inclusion criteria and they did not have any local or systemic effects with the ibopamine test. The mean PERG amplitude decreased significantly from baseline after 45 minutes during the ibopamine test (paired t test = 0.05). The results were statistically not correlated with the positivity to the ibopamine test (p = 0.5)., Conclusions: These data stress that, even in presence of a moderate and transient IOP increase, inner retinal function of patients with OHT may be transiently affected.

Purpose: To report a case of pulmonary edema, in a child under general anesthesia, due to iatrogenic acute hypertensive crisis following instillation of 1 drop of 5% phenylephrine eyedrops., Methods: A 2-year-old boy was scheduled for examination of both eyes and enucleation of the left eye under general anesthesia. In the preoperative ward, 1 drop of 2.5% phenylephrine eyedrops was instilled 3 times by the nursing staff. The child was induced with the volatile agent Sevoflurane and intubated with Inj atracurium besylate 0.5 mg/kg IV. Anesthesia was maintained with N2O/oxygen (2:1)/Sevoflurane 1.5% and Inj fentanyl 1 µg/kg IV. As the pupil was not dilated optimally for examination, 1 drop of 5% phenylephrine eyedrops was instilled. Approximately 10 minutes following its instillation, tachycardia and rise in blood pressure occurred. Auscultation of the chest revealed bilateral coarse crepitations and pink frothy secretions were noted in the Portex endotracheal tube., Results: Pulmonary edema was effectively settled using positive pressure ventilation with 100% oxygen, Inj lasix 1 mg/kg IV, and Inj hydrocortisone 100 mg IV. The concentration of inhalational agent, Sevoflurane, was increased. Within about 15 minutes, both heart rate and blood pressure gradually returned to normal limits. Following surgery, the child was extubated, fully awake., Conclusions: To produce maximum mydriasis, with minimum systemic effects, preventive strategies such as using the lowest drug concentration, punctual occlusion, eyelid closure, allowing adequate time for the pharmacologic effect to occur, and the use of microdrops in infants should be adopted.

Purpose: To compare the mydriatic efficacy and cardiovascular safety of the mydriatic options., Methods: This was a prospective randomized analysis of 90 eyes submitted to senile cataract surgery. Group A (30 eyes) included topical mydriasis, group B (30 eyes) included mydriasis with the ophthalmic insert (Mydriasert), and group C (30 eyes) included intracameral mydriasis. Measures were mydriasis value before ophthalmic viscoelastic device (OVD) injection and at the end of surgery, blood pressure and heart rate, need for antihypertensive medication, and subjective iris stability., Results: Before OVD injection and at the end of surgery, pupillary dilation was 8.1 and 7.0 mm in group A, 8.2 and 7.7 mm in group B, and 6.3 and 6.1 mm in group C, respectively. Mean surgery time was 8.3 min in group A, 8.1 min in group B, and 12.3 min in group C (p<0.05). The mean subjective iris stability score was 8.7/10 in group A, 9.3/10 in group B, and 6.1/10 in group C (p<0.05). Systolic blood pressure was greater than 180 mmHg in 9 (30%) patients in group A, 3 (10%) in group B, and 2 (6.6%) in group C. Antihypertensive medication was administered to 8 (26.6%) cases in group A, 2 (6.6%) in group B, and 0 (0%) in group C (p<0.05)., Conclusions: The most effective mydriasis was obtained within the Mydriasert group, followed by the topical mydriasis group. From the cardiovascular point of view, intracameral mydriasis was the safest and topical mydriasis the least safe.

Purpose: To compare the mydriatic effects of 2% ibopamine and collyrium containing 10% phenylephrine + 0.5% tropicamide and to study the associated drug in patients with ocular pseudoexfoliation (PEX) syndrome., Methods: This was a prospective, comparative, interventional clinical study. The study group consisted of 20 patients with ocular PEX syndrome. Intervention procedures included administration of 10% phenylephrine-0.5% tropicamide versus 2% ibopamine versus 2% ibopamine followed by the combination drug. Main outcome measurement was mydriatic efficacy measured in terms of mean pupil diameter. Adverse effects on intraocular pressure (IOP) were measured with a Goldmann applanation tonometer. Mean premedication pupil diameters in all patients were less than 3.5 mm., Results: Instillation of 10% phenylephrine-0.5% tropicamide caused significantly greater mydriasis than 2% ibopamine (pupil diameters: 6.17 mm, SD=1.14 versus 5.33 mm, SD=1.34; p<0.001). Combined use of both collyria significantly increased mydriasis (7.19 mm; SD=0.69) compared with that induced by either of the products alone (p<0.001). Inadequate mydriasis (pupil diameters < 5.5 mm) was observed in 2 patients after administration of 10% phenylephrine-0.5% tropicamide and in 10 following instillation of 2% ibopamine, but the addition of 10% phenylephrine -0.5% tropicamide to ibopamine-treated eyes resulted in adequate dilation in all cases. IOP increases of 4 mmHg over baseline values were observed in 12 (60%) patients after 2% ibopamine., Conclusions: In patients with ocular PEX, instillation of 2% ibopamine exerts a significant additive effect on mydriasis induced with 10% phenylephrine-0.5% tropicamide with only minimal increases in IOP.

Purpose: To evaluate anterior chamber biometry of the eyes of normal children using ultrasound biomicroscopy (UBM) and to evaluate the differences in biometry between children and adults, and before and after pupil dilation in children., Methods: Anterior chamber depth (ACD) and trabecular-iris angle (TIA) were measured in 94 normal children and 15 normal adults using UBM. Before and after pupil dilation were measured in 42 children with emmetropic and hyperopic eyes., Results: In 66 emmetropic children, ACD and TIA were 2.93+/-0.18 mm and 34.42+/-4.02 degrees, respectively. In 28 hyperopic children, ACD and TIA were 2.92+/-0.21 mm and 35.05+/-4.42 degrees, respectively. There was no significant difference in anterior chamber biometry associated with the refraction. ACD did not differ between children and adults, but TIA in children was wider than in adults. There was no significant difference in ACD or TIA before versus after pupil dilation in any case., Conclusions: Anterior chamber biometry in children showed no differences before and after pupil dilation. Also, there was no difference in ACD of children as compared to adults; however, TIA in children was significantly wider than in adults.

Purpose: To investigate changes of crystalline lens position during accommodation in children with emmetropia, myopia, and hyperopia., Methods: A total of 188 children (372 eyes) from 4 to 19 years old (mean age 11.3+/-4.43) with cycloplegic refractive error within a range +9.00 D to -9.00 D were enrolled. After a general ophthalmic examination, ultrasound biometry was performed, with the eye at a maximal accommodative effort. Cycloplegia was induced by triple installation of 1% tropicamide drops and 30 minutes later the biometric examination was repeated., Results: In emmetropic eyes in the process of accommodation, the anterior pole of the crystalline lens moved forward by 0.144+/-0.14 mm (p< or =0.001); the position of the posterior pole did not change. In myopic eyes, the anterior pole moved forward by 0.071+/-0.13 mm (p< or = 0.001) and the posterior pole moved backward by 0.039+/-0.10 mm (p=0.003). In hyperopic eyes, the whole lens translocated anteriorly: anterior pole moved forward by 0.242+/-0.16 mm (p< or = 0.001) and posterior pole moved forward by 0.036+/-0.09 mm (p< or = 0.001). Differences among emmetropia, myopia, and hyperopia were statistically significant. Forward movement of the posterior pole correlated with a low axial length of the eye, and also with plus refractive error and with a smaller accommodative increase of lens thickness., Conclusions: In children, accommodative changes of the crystalline lens position depend on refractive status.

Purpose: To determine the optimal dosage of cyclopentolate for adequate cycloplegia with minimal side effects., Methods: A prospective randomized clinical trial of patients 3.5 to 20 years of age referred to a strabismus clinic during a 1-year period. Eligible patients were randomly divided into three groups. In Group 1, the cycloplegic effect of one drop of cyclopentolate was compared with two drops; in Group 2, the effect of two drops was compared with three drops; and in Group 3, the effect of one drop was compared with three drops., Results: This study includes 192 eyes of 96 patients with a mean age of 11.0 +/- 5.7 years. Strabismus was present in 43 patients (44.8%). A total of 146 patients (76%) were hyperopic, 33 (17.2%) were myopic, and 13 (6.8%) were slightly hyperopic or myopic at the two stages of the study. Overall, only 16 eyes, including 9 eyes in Group 1 (16.4%), 2 eyes in Group 2 (3.2%), and 5 eyes in Group 3 (8.6%), had > or = 0.5 D difference in spherical equivalent refractive error at two stages of the study; however, intergroup differences were not statistically significant (p=0.16, chi-square test). Within each group, the percentage of eyes with <0.5 D difference was significantly greater than those with > or = 0.5 D difference (p<0.001 in all three groups, binomial test). Side effects were more prevalent using more frequent drops., Conclusions: A single drop of cyclopentolate 1% suffices for cycloplegic refraction. There were less frequent side effects using one drop of cyclopentolate, compared to two or three drops.

Purpose: Ibopamine is a prodrug of N-methyldopamine that has a non-cycloplegic mydriatic action due to its alpha-adrenergic properties and is able to induce, when topically given, a transient increase of intraocular pressure (IOP) in eyes with hydrodynamic disorders., Methods: This is a randomized, crossover, open-labeled, two- center study. Forty patients (20 open-angle glaucoma patients and 20 healthy subjects) were treated with ibopamine 2% eye drops and phenylephrine 10% eye drops., Results: Ibopamine induced a significant increase in IOP only in glaucomatous eyes (p<0.001) without a significant hypertensive effect in normal eyes. Ibopamine and phenylephrine showed a similar mydriatic activity but ibopamine was able to induce an hypertensive effect only in glaucomatous eyes., Conclusions: The results confirm the use of ibopamine as provocative test in detection of hydrodynamic disorders.

Purpose: On the basis of intraocular pressure measurements and fluorophotometry we assessed the effects of 2% ibopamine eye drops on aqueous humor production in normal and glaucomatous eyes., Methods: Thirty subjects (15 healthy volunteers and 15 open-angle glaucoma patients with ocular hypertension) were included in a placebo-controlled study with random assignment of treatment from masked containers. All subjects underwent ophthalmologic examinations and intraocular pressure (IOP) measurements. Fluorophotometry was done in both eyes at baseline (without treatment) and during treatment. Each subject was treated with 1 drop of 2% ibopamine in one eye and 1 drop of placebo in the fellow eye 30 minutes before fluorophotometric scans and every hour after the first instillation (for a total of 4 times). Safety was evaluated by recording adverse events and ocular symptoms and signs. Aqueous humor flow data were analyzed using the paired t-test, comparing ibopamine and placebo-treated eyes., Results: No changes in IOP were detected in normal eyes, whereas glaucomatous eyes showed a mean increase of 4 mmHg (95% CI 3.46-4.51) from baseline. The difference in IOP between healthy eyes and those with glaucoma was significant (p < 0.0001). In normal eyes and patients with glaucoma ibopamine led to a significant increase in aqueous humor flow compared with placebo-treated eyes (p < 0.01). The safety profile of ibopamine was very good., Conclusions: The results seem to confirm that ibopamine increases aqueous humor production in normal and glaucomatous eyes, raising IOP only in eyes with glaucoma.

Purpose: To assess the efficiency of pupillary stretching with iris hooks in poorly dilatable pupils during phacoemulsification., Methods: Forty eyes with maximal preoperative mydriasis less than 4.5 mm (mean 3.9 mm S.D. 1.0) received bimanual pupillary stretching according to the technique of Miller and Keener (1994)., Results: Small pupils were mainly caused by long-term pilocarpine therapy (n = 21), posterior synechia (n = 11) or diabetic iridopathy (n = 7). With multidirectional stretching, the pupil could be enlarged to mean 6.6 mm (S.D. 0.66), lasting throughout phacoemulsification. The effect of stretching was significantly greater in eyes with synechias, but no significant differences in post-operative pupil motility was observed between the three subgroups. Six eyes with pronounced postoperative inflammation responded well to antiinflammatory treatment., Conclusions: Done with routine surgical instruments, bimanual pupillary stretching seems to be an easy, safe and effective procedure for enlarging small pupils by an average of 2.7 mm during phacoemulsification, especially in eyes with posterior synechias.

The pupils of neonates and premature infants often need to be dilated for retinal examination. The drops used for this purpose have some known side effects. This study investigated the effects and side effects of these drops. In this prospective randomized study, 80 healthy neonates were randomly assigned to eight groups. In Group A 1% cyclopentolate was used; in Group B 1% tropicamide; in Group C 2.5% phenylephrine; in Group D 1% cyclopentolate and 1% tropicamide; in Group E 2.5% phenylephrine and 1% tropicamide; in Group F 0.5% cyclopentolate, 0.5% tropicamide and 2.5% phenylephrine; in Group G 1% cyclopentolate and 2.5% phenylephrine and in Group H 0.9% NaCl. Heart rate, systolic and diastolic blood pressures were recorded before, and 5, 10, 15, 30, 45, 60 minutes after instillation of the drops. Pupillary size was measured at baseline, 30 and 60 minutes. To stimulate the conditions of indirect ophthalmoscopic examination, the pupil sizes were measured under the intense beam of a halogen light. The results were analyzed statistically. Maximum side effects were seen in group C; the safest was group B and maximum mydriasis was achieved in group F.