Mydriatic Effect Research Articles

Mydriasis in eastern box turtles (Terrapene carolina carolina) following topical administration of proparacaine, 10% phenylephrine, and rocuronium bromide.

To determine the mydriatic effect of topical 10% phenylephrine with 10 mg/mL rocuronium bromide and compare this protocol with and without pretreatment with proparacaine. Ten client-owned pet adult eastern box turtles (Terrapene carolina carolina). All turtles were sedated with 8 mg/kg alfaxalone intramuscularly. One group of four turtles received four 20 μL drops of 10% phenylephrine and four 20 μL drops of rocuronium bromide in the right eye. Another group of four turtles received one standard drop of proparacaine followed by four 20 μL drops of 10% phenylephrine and four 20 μL drops of rocuronium bromide in the right eye. Two control group turtles received four 20 μL drops of saline in the right eye. The left eye was untreated in all turtles. Drops of the same type were separated by 2 min while drops of different types were separated by 5 min. Pupil size was recorded at 0, 15, 30, 60, 90, 120, 180, 240, and 360 min after administration of the final drop. Treatment with 10% phenylephrine and rocuronium bromide resulted in pupil diameter changes from baseline that were statistically significant from zero at 60, 90, and 120 min in the non-proparacaine group and 90 min in the proparacaine group. The time to peak effect was 90 min in the proparacaine group and 75 min in the non-proparacaine group. Saline-treated pupils in the control group decreased in diameter over the study period. Overall, the treated eyes of the proparacaine group and non-proparacaine group were not different from each other, but both dilated more than the control group. Rocuronium bromide and 10% phenylephrine can produce effective and safe mydriasis in eastern box turtles, but there was wide interindividual variation in effectiveness. Proparacaine did not improve the mydriatic effect.

Ophthalmic findings and parameters in Western tiger salamanders (Ambystoma mavortium) from northern Colorado.

The aim of this study was to document ophthalmic examination findings and provide reference values for ocular examinations and diagnostics in clinically normal Western tiger salamanders (Ambystoma mavortium) and to evaluate the mydriatic effect of a topical rocuronium bromide and identify any adverse effects. Sixteen Western tiger salamanders. A complete ophthalmic examination, including intraocular pressure via rebound tonometry [iCare® TonoVet (dog-setting) or iCare® TonoVet Plus (dog-setting)], and fluorescein and Rose Bengal stains, was performed. Ocular surface flora culture swabs were collected for microbiology in four salamanders. Rocuronium bromide (50 μL; 0.01 mg) was administered into each eye in three salamanders. Pupil size and constriction ability were evaluated up to 60 min following administration of rocuronium bromide. Distant visual examination and Doppler heart rate were used to monitor for potential adverse effects of rocuronium bromide. Observed ocular abnormalities included lipid keratopathy/keratitis (19%; 3/16), parasitic ophthalmitis (19%; 3/16), and cataracts (6.3%; 1/16). A significant difference was found between tonometry with iCare® TonoVet (11.5 ± 2.7 mmHg) versus TonoVet Plus (15.4 ± 3.7 mmHg) (p = .025). Fluorescein and Rose Bengal stains were negative in all salamanders. Ocular surface microbiology revealed a high incidence of contamination from environmental flora, with the most common isolate being unidentified as Gram-negative nonfermenters (75%; 3/4). No significant change in pupil size or constriction ability was observed with rocuronium bromide. This is the first study to document ocular examination findings and diagnostics in captive and wild urodeles and may serve as a reference for clinical assessment and future studies of the Western tiger salamander.

The long-term effects of topical latanoprost 0.005% treatment on pupillary functions: A 2-year longitudinal study.

To investigate the long-term effects of topical latanoprost 0.005% treatment on pupillary functions in early-stage primary open-angle glaucoma (POAG) eyes using automated pupillometry. This prospective study involved 20 eyes of 20 treatment-naive subjects with early-stage POAG. After comprehensive ophthalmic examination, static and dynamic pupillometry measurements were performedbefore treatment, at the 1st follow-up visit (1.10 ± 0.30 months) and the 2nd follow-up visit (25.85 ± 10.26 months) after treatment initiation. Dynamic parameters included resting diameter (mm), amplitude (mm), latency (ms), duration (ms), and velocity (mm/s) of pupil contraction and dilation. Static pupillometry parameters were pupil diameter (PD, mm) in high-photopic, low-photopic, mesopic and scotopic conditions. The velocity of pupil dilation significantly decreased during the 1st visit (p = 0.008) and the 2nd visit (p = 0.0003) of treatment compared to the pre-treatment visit. The resting PD was also significantly higher after the 1st visit (p = 0.003) and the 2nd visit (p = 0.001) compared to the pre-treatment visit. However, the difference in resting PD measured between the 1st and 2nd visits did not reach statistical significance (p = 0.065). There were no significant changes in other dynamic parameters (p > 0.05 for all). Additionally, a mild, but not significant, mydriatic effect was observed in PD measurements under scotopic, mesopic and low photopic lighting conditions after follow-up. None of the static and dynamic parameters correlate with age, changes in intraocular pressure (IOP) or mean deviation (MD) values of visual field tests. The long-term topical latanoprost 0.005% treatment in early-stage POAG has a slight mydriatic effect on the pupil. Further longitudinal clinical studies with larger patient cohorts are necessary to better understand the effects of latanoprost on pupillary functions.

Can the Side Effects of Mydriatics Be Reduced with the ROP-bundle Protocol?

Can the Side Effects of Mydriatics Be Reduced with the ROP-bundle Protocol?

A Comparative Study of Vision Outcome Between Small Incision Cataract Surgery (SICS) and Phacoemulsification as Well as Comparison of Mydriatic Effects Between Two Drugs in Cataract Surgery Patients

Aims: Knowing the Mydriatic effect of Tropicamide and Cyclopentolate as well as the difference in vision improvement between phacoemulsification and small-incision cataract surgery. Study type and place: A prospective & cross-sectional study. Total number of cases 1446 were collected over a period of 6 month was conducted in Nagapattinam Government medical college. Objectives: To know the prevalence of cataracts on the basis of age and sex, To find the major systemic co-morbidities in cataract patients, To compare the pupil dilation between Tropicamide and Cyclopentolate, To compare the visual acuity after cataract surgery using SICS and phacoemulsification, To find drug utilization in pre- and post-operative cataract surgery Utilizing statistical analysis: The SPSS software package was used to compute and analyze the data. A 0.05 p value was deemed significant. Results: Among 1446 patients, gender distribution showed that 934 (65%) were female and 509 (35%) were male; According to age category, the majority of the patients in our study who have cataracts are between the ages of 60 and 79. The distribution of patients by eye wise was as follows: right eye (845, or 58%); left eye (601, or 42%); There were 624 cases of immature cataract (43%), 475 cases of mature cataract (32.8%), 289 cases of hyper-mature cataract (19.9%), and 58 cases of pseudophakia (4%).Patients undergoing cataract surgery frequently have diabetes and high blood pressure. One of the risk factors for cataract is diabetes (73.5%). SICS is more successful than phacoemulsification in terms of improving visual acuity, and since the pupil dilated larger with duration, it is Cyclopentolate rather than Tropicamide; Conclusions: By comparing visual acuity measured using the Snellen chart, there was a substantial difference in the visual outcome on the first postoperative day. Small-incision cataract surgery is more effective than phacoemulsification. The difference in pupil diameters between Cyclopentolate and Tropicamide demonstrates that the latter is less effective than the former. Keywords: Cyclopentolate, Diabetic mellitus, small incision cataract surgery, immature cataract, and female

ПРИРОДНЫЕ ПОЛИМЕРЫ КАК ВСПОМОГАТЕЛЬНЫЕ ВЕЩЕСТВА ДЛЯ ОПТИМИЗАЦИИ МИДРИАТИЧЕСКОГО ЭФФЕКТА ФЕНИЛЭФРИНА ГИДРОХЛОРИДА

A comparative in vivo study examined the main characteristics of the mydriatic effect of eye drops containing the active substance 2.5% phenylephrine hydrochloride with and without auxiliary components, as well as their effect on the ocular mucosa. The research was carried out on 40 mature male rabbits of the Soviet Chinchilla breed. The mydriatic effect of the drug when instilled into the conjunctival sac of an awake rabbit was studied. The local irritant effect of GDF eye drops on the cornea of the eye of an experimental animal was determined. A single instillation of 1 drop of a 2.5% solution of GDF phenylephrine hydrochloride containing hypromellose as an excipient exceeds the depth of the mydriatic effect of the drug without them, and in terms of the speed of achieving the maximum mydriatic effect and its duration, it is ahead of the effect of GLF containing hyaluronic acid. It is also not accompanied by the formation of a local irritant reaction to the cornea of a rabbit's eye, in contrast to a moderate reaction against the background of instillation. The results obtained suggest that the inclusion of hypromellose as an excipient in GDF eye drops with phenylephrine hydrochloride leads to optimization of the pharmacodynamics and pharmacokinetics of the active substance due to acceleration its penetration into the moisture of the anterior chamber of the eye, increasing local bioavailability and prolonging the exposure time of the substance.

Could this be a lead for a solution to negative dysphotopsia?

Negative dysphotopsia (ND) was diagnosed when the mydriatic effect waned off by 4 h after intraocular lens implantation providing time for the institution of immediate rectification measures. ND was a peripheral temporal visual field defect (VFD) and manifested as a 100% black shadow having an inner arc with a sharp, smooth, and concave edge and outer border extending to the temporal periphery. ND disappeared when two fingers were kept blocking the ND over the affected side within ≤1” of the temple. The extent of VFD varied with eye movement. Clinically, intraocular lens is the cause of ND and not neuroadaptation.

Changes in Wavefront Error of the Eye for Different Accommodation Targets under the Application of Phenylephrine Hydrochloride

Pharmacological dilation of the eye to have a larger pupil diameter may allow a better understanding of the wavefront error changes with accommodation. This work aimed to investigate whether dilation of the pupil with Phenylephrine Hydrochloride (PHCl) application changes the accommodative response and the Zernike coefficient magnitude with accommodative demand when computed to a common pupil size. Sixteen right eyes of healthy young subjects were measured with the commercial Hartmann–Shack aberrometer IRX3 (Imagine Eyes, Orsay, France) 30 min after two drops of 1.0% PHCl were applied. The eye wavefronts for accommodative demands from 0 to 5 D were measured in natural conditions and after pupil dilatation. Statistically significant differences between both conditions were found for the Zernike coefficients C3−1, C31, C40 and C60. Without the effect of PHCl, higher values were found for all higher-order Zernike coefficients (HOA). With increased accommodative response, an increase of C3−1 and a decrease of C31 was observed and the C40 becomes more negative; the change from positive to negative is shown in the accommodative demand of 1.5 D. Conversely, C60 increases with increasing accommodative demand. To conclude, the results demonstrated that the mydriatic effect of PHCl causes changes in the magnitude of HOA when accommodation is stimulated. The trends observed in the different Zernike coefficients were the same reported in previous studies.

Hypromellose improves mydriasis dynamics by phenylephrine in a rabbit experimental model

Purpose: to determine the main characteristics of the mydriatic effect of drug formulations of phenylephrine, containing and not containing hypromellose, hyaluronic acid as an auxiliary component, in a comparative in vivo study, as well as to study their local bioavailability and the effect on the mucous membrane of the eye. Materials and methods. The studies were carried out on 40 adult male Soviet Chinchilla rabbits. The research model involved the mydriatic impact and the local irritant effect of the drug when instilled into the awake rabbit’s conjunctival sac. The peak concentration of phenylephrine, which is part of all formulations studied, was determined in the aqueous humor of the anterior chamber of the animal's eye at the 5-minute point by high-performance liquid chromatography with tandem mass spectrometric detection. Results. A single instillation of 1 drop of a 2.5% solution of phenylephrine hydrochloride containing hypromellose as an excipient is superior in depth, rate of reaching the maximum mydriatic effect and its duration to the formulation that does not contain hypromellose as an excipient. Only in a few cases, drug formulations containing hypromellose caused an insignificant weak reaction of eyelid closure, in contrast to a moderate local irritant reaction of the rabbit's eye occurring when phenylephrine solution without hypromellose is instilled. Peak concentrations of phenylephrine in the aqueous humor of the anterior chamber of the eye determined 5 minutes after instillation of 1 drop of 2.5% phenylephrine solutions containing hypromellose significantly exceed those occurring when phenylephrine drugs of the same concentration that do not contain hypromellose are instilled. Conclusion. The inclusion of hypromellose as an auxiliary substance into the formulation of phenylephrine eye drops optimizes the pharmacodynamics and pharmacokinetics of the active substance due to faster penetration into the eye anterior chamber aqueous humor, increasing local bioavailability and prolonging the exposure time. In addition, the absence of a local irritating effect of such forms on the eye tissues may also be explained by the presence of hypromellose.

Study on the Effect of Topical Pre-operative Nonsteroidal Anti-inflammatory Drugs in Maintaining Mydriasis during Small Incision Cataract Surgery

A prospective, randomized, double masked, single centered comparative study done in the Bangladesh Naval Ship Patenga, Chattogram, Bangladesh, from July 2021 to June 2022, to assess the clinical benefits and effectiveness of prophylactic pre-operative topical administration of NSAIDs in maintaining mydriasis during small incision cataract surgery. Thirty patients underwent small incision cataract surgery with intra ocular lens implantation were randomized to compare the efficacy of topical NSAIDs drops (Group-A) and placebo drops (Group-B) in maintaining peroperative mydriasis. Balanced salt solution containing non preservative adrenaline was used in all patients. Pupil size was measured prior to the corneal incision and after the completion of the operation. The two groups were analyzed with respect to the changes in pupillary diameter at the beginning and at the end of the operation. The change in pupil size was significantly different among the two groups at the end of the surgery. The mean vertical and horizontal diameter of the two groups were near about similar at the beginning of the surgery. Significant differences were seen after IOL implantation with the NSAIDs group having the larger mean diameter in both vertical (P=0.003) and horizontal (P=0.008) pupillary measurements at the conclusion of surgery. Topical NSAIDs has been shown to be a more effective inhibitor of meiosis during per operative uncomplicated small incision cataract surgery and provides a more stable mydriatic effect during surgery compared to the placebo group.
 CBMJ 2023 January: Vol. 12 No. 01 P: 22-26

Клиническое и экспериментальное обоснование применения фенилэфрина с гипромеллозой в лечении перенапряжения аккомодации у пациентов с миопией

Aim: to perform a comparative analysis of the clinical efficacy of 2.5% phenylephrine with and without hypromellose for the treatment of extra accommodation strain in schoolchildren with myopia and to perform an experimental evaluation of the pharmacological effective of active ingredient of the finished dosage form (FDF) of preparations containing 2.5% phenylephrine with and without excipients. Patients and Methods: this clinical study enrolled 122 schoolchildren, 11–17 years old, with extra accommodation strain of various severity. The children were split into two groups. The group 1 patients received Irifrin® BK, containing 2.5% phenylephrine with hypromellose, one eye drop at the bedtime during 30 days, and the group 2 patients — Preparation A (2.5% phenylephrine without hypromellose) according to the same dosage regimen. The accommodative function was evaluated using the Speedy-i accommodation analyzer, and the coefficients of accommodation response before and 30 days after the treatment were determined. The experimental study was carried out in 40 sexually mature male rabbits of the Soviet Chinchilla breed to evaluate the development and duration of mydriatic effect and to measure the concentration of active ingredient — phenylephrine with hypromellose, as an excipient (Irifrin® and Irifrin® BK), phenylephrine without hypromellose (Preparation A) and phenylephrine with sodium hyaluronate as an excipient (Preparation B) in the aqueous humor within the eye anterior chamber using high-performance gas-liquid chromatography with tandem mass spectrometric detection. Results: the drug therapy of extra accommodation strain comprising 2.5% phenylephrine hydrochloride solution with hypromellose as an excipient (Irifrin® BK) demonstrated a decrease in severity of extra accommodation strain after 30 days of treatment. At the same time, Preparation B did not demonstrate its efficacy. In the experimental study, Irifrin® and Irifrin® BK were superior to Preparations A and B (without hypromellose as an excipient) as regards the peak mydriatic effect and the time required to reach maximal mydriasis. The peak phenylephrine concentrations in the aqueous humor within the eye anterior chamber were reached five minutes after instilling 1 drop of 2.5% phenylephrine with hypromellose solutions. These peaks were significantly higher than those observed after instilling Preparations A and B — phenylephrine in the same concentration but without hypromellose. Conclusion: the addition of hypromellose as an excipient to FDF of 2.5% phenylephrine solution helps to optimize pharmacodynamics and pharmacokinetics of the active ingredient by accelerating its inflow in the aqueous humor within the eye anterior chamber, increasing the topical bioavailability, and extending the exposure interval. It is likely that the above factors have underpinned the efficacy of Irifrin® and Irifrin® BK drugs used for the treatment of extra accommodation strain. The same results were obtained in this study comparing the clinical efficacy of 2.5% phenylephrine solution with hypromellose and its preparations without hypromellose used for the treatment of schoolchildren with extra accommodation strain amid myopia, as proven by the significant improvement of the accommodation indices during the treatment. Keywords: extra accommodation strain, mydriatic effect, peak concentration, rabbit, myopia, phenylephrine, hypromellose. For citation: Makhova M.V., Shikh E.V., Strakhov V.V. et al. Clinical and experimental rationale for using phenylephrine with hypromellose for the treatment of extra accommodation strain in patients with myopia. Russian Journal of Clinical Ophthalmology. 2023;23(1):33–38 (in Russ.). DOI: 10.32364/2311-7729-2023-23-1-33-38

Effect of gentamicin on mydriasis in rabbit’s eye

Background: In our ophthalmology outpatient department, routinely to observe the posterior segment of the eye and the fundus of the eye, we use various mydriatics such as atropine, cyclopentolate, and tropicamide for various indications. As there are a lot of mydriatics clinically used, taking much time for dilation, any add-on drug can be used for dilatation of pupils helping the underlying drugs for a better outcome. This study provides information regarding the effect of topical administration of gentamicin on horizontal pupillary diameter (HPD) over and above use of other mydriatics in rabbit’s eye. There are no similar studies in the past. Aims and Objectives: The aim of this study was to evaluate the effect of gentamicin on the HPD of rabbit’s eye. Materials and Methods: After taking the Institutional Ethics Committee clearance, 48 rabbits were taken into this study and were divided into 2 groups of 24 rabbits each. HPD was measured in both eyes before starting the experiment. Gentamicin eye drops were instilled in the right eye (test) and normal saline in the left eye (control) in both groups of 24 each. HPD was measured in both eyes after 30 min of instilling drops, and readings were noted. Thereafter, homatropine hydrobromide was instilled in both eyes in the first group (24 rabbits), and phenylephrine hydrochloride in the second group (24 rabbits). HPD in both eyes was measured every 5 min for 30 min. Results: After 30 min of instilling gentamicin eye drops in the test eye, there was no change in HPD; however, after instilling a mydriatic agent (homatropine or phenylephrine), there was an early onset of mydriasis as well as marked mydriasis in test eye compared to control eye in both groups. Hence, the differences in HPD between both eyes (test and control eye) were statistically not significant (P = 0.083). Conclusion: Topical application of gentamicin does not have a mydriatic effect, but it potentiates the mydriatic effect of homatropine and phenylephrine in rabbit’s eye.

COMPARISON OF THE DILATING EFFECT OF THREE MYDRIATIC AGENTS ON DARK IRIDES

Dilation of pupil has been a major component of diagnostic eye examination inOptometric practice. Although mydriatic agents are used in clinical procedures, thereis no satisfactory explanation for the preference of one over another. This studycompared the dilating effect of three different mydriatic agents on dark irides ofninety healthy subjects; comprising 48 males and 42 females aged 16-30 (mean age18.77±0.52) years divided into three groups of 30 subjects each. One drop of 1%tropicamide eye drop was instilled into the right eye of Group 1 subjects, One drop of1% homatropine eye drop was instilled into the right eye of Group 2subjects, whileOne drop of 2.5% phenylephrine eye drop was instilled into the right eye of Group 3subjects, The left eye (control eye), received a placebo of one drop of 10mg/mlBenzyl Alcohol in all the subjects in the three groups. Baseline measurements wererecorded prior to instillation, thereafter mydriatic effect was assessed over a periodof 40 minutes starting at 5 minutes and thereafter at 10 minute interval using thehand held pupillometer. Results showed that after 40 minutes of instilling the 3mydriatic agents to the right eyes, there was a statistically significant difference(p<0.05) in the pupil diameter of all the subjects in the three groups .Maximum meanpupillary dilation was 7.10±0.27mm, 6.00±0.56mm, and 4.80±0.36 mm for 1%tropicamide, 1% homatropine, and 2.5% phenylephrine respectively after 40minutes. Therefore it can be concluded that significant differences exist in themydriatic effect of the three mydriatic agents.

Evaluation of Pharmacological and Clinical Prophylactic Efficacy of Scrofoloso-12 Group of Electrohomoeopathy Medicine in Eye Disorder

Eye disorder is the most common issue in today’s era. Hundreds of various eye disorders and eyesight issues exist. Some diseases are incurable, while many others can be treated. The modern system of medicine works incredibly with advanced techniques and formulations relevant to eye disorder but has certain limitations. Electrohomoeopathy is a new system of medicine founded by Dr. Count Cesare Mattei where the plant is the main source of preparation of medicine. In Electrohomoeopathy we study individual and combination plants show the synergistic effect when specific essence is rationally mixed together to form an effective group against the eye disorder. Spagyric medicine is an old form of natural medicine that has been tested, researched, and practiced for decades. In this article, we are going to discuss the pharmacological activity and the effectiveness of the Scrofoloso-12 group of Electrohomoeopathy medicine with the help of the animal model. Subsequently, we are going to evaluate and correlate the efficacy of Scrofoloso-12 group use in various eye disorders during clinical practice. Hence, the present study focuses on the scientific investigation of the effectiveness of the S12 group against Atropine induced corneal, light reflux, and mydriatic effect of rabbit models.

Persistent Pupillary Dilatation After Cycloplegic Refraction in Child Taking Systemic Benzatropine

Cyclopentolate is a substance that has a mydriatic and cycloplegic effect and is used frequently by ophthalmologists before pediatric glasses prescription. In this case, a child came to the clinic for glasses prescription, but later her pupil didn’t return to normal size even after using the antidote (Pilocarpine eye drop 2%). Accidentally, we found that she is on systemic medication containing Benztropine which has a mydriatic effect. After the stoppage of the systemic Benztropine, the pupils return to their normal size after two weeks. That case gives an important rationale to check the medications taken by the patient before giving cycloplegic drugs, which could help in the diagnosis and treatment of mysterious situations. Keywords Benzatropine; Cyclopentolate; Eye Medication; Ophthalmology

Effects of oral function on pupil response: a new view on bruxism pathophysiology.

There is increasing evidence of the influence of the oropharyngeal stimulations on the autonomic nervous system and an easy approach to evaluate the balance between parasympathetic and sympathetic system is the measurement of the pupil diameter. The aim of this analytic observational study is to define the effects of clenching and swallowing on pupil diameter, and how an oral appliance can affect the outcome of these tasks, to establish their influence on the sympathetic-parasympathetic balance. We measured the pupil diameter in 30 healthy subjects during clenching and swallowing, both with and without oral appliance. We compared the results with the mandibular rest position. The respective positions with and without oral appliance were also compared. Pupillometry showed a mydriatic effect of swallowing (rest 6.94 mm, swallowing 7.26 mm, P=0.04) and oral appliance, more relevant in scotopic conditions. On the contrary, clenching seemed to enhance miosis, especially in intense brightness condition (rest 3.95 mm, clenching 3.83 mm, P=0.02). Swallowing and oral appliance facilitate the sympathetic system, while clenching activates the parasympathetic branch. We argue that probably the locus coeruleus is the main hub. These results could have practical implications in bruxism physiology, because it could be an attempt to counteract the activation of the sympathetic system.

The Eff ects of Diff erent Mydriatics on Intraocular Pressure and Central Corneal Thickness in New Zealand White Rabbits

The Eff ects of Diff erent Mydriatics on Intraocular Pressure and Central Corneal Thickness in New Zealand White Rabbits

The Eff ects of Diff erent Mydriatics on Intraocular Pressure and Central Corneal Thickness in New Zealand White Rabbits

The Eff ects of Diff erent Mydriatics on Intraocular Pressure and Central Corneal Thickness in New Zealand White Rabbits

Effects of different mydriatics on the choroidal vascularity in healthy subjects.

To evaluate choroidal vasculature changes after the instillation of mydriatic parasympatholytic and sympathomimetic agents in healthy subjects. A total of 95 healthy subjects were enrolled in this prospective, randomized comparative study. Study participants were divided into three different groups depending on the drug to be administered: tropicamide (1%) group (n = 31), tropicamide (0.5%) + phenylephrine (10%) group (n = 30) and control group receiving artificial tears (n = 34). All participants underwent a complete ophthalmological examination including best corrected visual acuity, refractive status and axial length. Subfoveal choroidal thickness (CT), total choroidal area (TCA), luminal and stromal choroidal area (LCA and SCA) and choroidal vascularity index (CVI) were measured before and after eye drops instillation. All the baseline characteristics were matched between the three groups (all P > 0.05). Before the mydriatic instillation, there were no significant differences of CT, TCA, LA, SCA, and CVI among the three groups (all P > 0.05). After drug administration, CT, TCA, LCA, SCA, and CVI did not show any significant change as well (respectively, P = 0.265; P = 0.483; 0.573; P = 0.405 and P = 0.708). Instillation of mydriatic eye drops did not induce significant changes of the choroidal vasculature, suggesting that their use do not alter CT and CVI evaluation.

Hemodynamic Changes Associated with Mydriatic Eye Drop Administration in Anesthetized Pediatric Patients

Background: Dilating eye drops are routinely used in pediatric retinoblastoma patients during anesthetized ophthalmologic exams. Information on the systemic effects of ocular mydriatics, especially in anesthetized pediatric patients, is limited. Objective: The primary aim of this study was to analyze hemodynamic changes during mydriatic eye drop administration in anesthetized pediatric patients. Methods: A retrospective chart review was performed for pediatric retinoblastoma patients who underwent MRI with anesthesia. Baseline blood pressure (BP) and heart rate (HR) were charted for each patient at induction. HR and mean arterial pressure (MAP) measurements were recorded at 5, 10, 15, 30, and 45 min after eye drop administration. Secondarily, we included data from 15 patients who received dilating eye drops while under sevoflurane general anesthetic. All patients were dilated with phenylephrine 2.5 or 10% (depending on age) and tropicamide 1%. Results: The final analysis included 176 anesthesia encounters. The results demonstrate no statistically significant deviation of more than 20% from baseline for either HR or MAP. Additionally, we did not detect any difference between patients who were anesthetized with propofol versus sevoflurane. Conclusions: We did not observe significant hemodynamic instability with administration of dilating eye drops during propofol anesthesia.