Astigmatic Anisometropia Research Articles

The effects of hyperopic and astigmatic ametropia on stereoacuity by Titmus stereo test

PurposeUsing the Titmus stereo test to examine the association between hyperopic ametropia including hyperopia, astigmatism, anisometropia, and stereoacuity in a school-aged population. MethodsWe measured cycloplegic autorefraction, best corrected monocular visual acuity and best corrected stereoacuity in a population of 4- to 13-year-old school-aged children (Keelung, Taiwan) after obtaining proper informed consent. Children with amblyopia (best-corrected visual acuity inferior to 20/25) or strabismus were excluded from the study. The effects of the severity of hyperopia, astigmatism, and anisometropia on stereoacuity revealed by the Titmus stereo test were analyzed. ResultsOne hundred and seventeen children (51 boys and 66 girls; mean age=7.32 years, range=4–13 years) with hyperopia were enrolled into the study. The mean spherical error was +1.48±1.30 diopters (D) (range=+0.25 to +6.50D). The mean astigmatism was -1.22±1.04 D (range=0 to -3.50 D). They received the Titmus stereo test. A spherical error > +3.00 D and spherical equivalent > +3.00 D showed a strong association with decreased stereoacuity in the Titmus stereo test (p=0.000). The degree of astigmatism or astigmatic anisometropia was not significantly correlated with the stereopsis in the test. ConclusionThe Titmus stereo test revealed a good quantification of the stereoacuity. A spherical error > +3.00 D, and a spherical equivalent > +3.00D were all associated with a significantly reduced stereoacuity in school-aged children.

Association between Ocular Dominance and Spherical/Astigmatic Anisometropia, Age, and Sex: Analysis of 10,264 Myopic Individuals

To determine the association between ocular dominance and spherical or astigmatic anisometropia, age, and sex. Medical records of 10,264 myopic refractive surgery candidates were filtered. Ocular dominance was assessed with the hole-in-the-card test. Manifest refractive error was measured in each subject and correlated to ocular dominance. Only subjects with corrected distance visual acuity (CDVA) of >20/22 in each eye were enrolled, to exclude amblyopia. Associations between ocular dominance and refractive state were analyzed by means of the t-test, χ(2) test, Spearman correlation, and multivariate logistic regression analysis. Right and left eye ocular dominance was noted in 61.7% and 35.6% of the individuals. Ocular dominance had no significant impact on SE refraction in subjects with SE or cylindrical anisometropia <0.5 D. For anisometropia >2.5 D (n = 278) the nondominant eye was more myopic in 63.7% (SE -5.8 ± 2.64 D) compared to 36.3% (-4.69 ± 2.39 D; P < 0.001; adjusted P (Padj) < 0.001) for the dominant eye being more myopic. Nondominant eyes showed higher astigmatic power than dominant eyes (-0.95 ± 0.91 D versus -0.89 ± 0.84 D; P < 0.001). For astigmatic anisometropia >2.5 D, nondominant eyes exhibited a higher amount of astigmatism in 75% of subjects. Nondominant eyes of subjects <29 years and 30 to 39 years of age had a significantly higher astigmatic power than did dominant eyes of the same age group. In contrast to previous reports, this study, including myopic refractive surgery candidates, revealed that the nondominant eye was more myopic for SE anisometropia >2.5 and more astigmatic for cylindrical anisometropia >0.5 D.

Treatment of Periocular Infantile Hemangiomas with Propranolol: Case Series of 18 Children

To study the efficacy of propranolol in the treatment of periocular infantile hemangiomas (IHs). Retrospective interventional case series. Eighteen children presenting periocular IH with occlusion of the pupil, anisometropic astigmatism, proliferating eyelid IH, or cosmetically disfiguring periocular IH. All patients received treatment with propranolol started at 0.5 mg/kg/day with an incremental increase by 0.5 mg/kg/day every 4 days, up to a maximum of 2 to 3 mg/kg/day. Complete eye examinations and serial photographs were obtained before, during, and after treatment. Doppler ultrasound and magnetic resonance imaging performed pre- and post-treatment were compared when available. Evolution of the treated IH was evaluated with respect to astigmatism, amblyopia, and size of the lesion. The IH size decreased in 17 of 18 patients. We noted a greater reduction when treatment was administered during the proliferative phase of growth of IHs. At the conclusion of treatment, none of our patients had amblyopia. The mean value of amblyogenic astigmatism (n = 7) decreased from 2.71 diopters (D) pretreatment to 1.03 D post-treatment. On radiology, 8 patients had significant regression of the lesion size of their IH and 1 patient had a limited progression. Propranolol had to be temporarily discontinued in only 1 patient because of symptomatic hypotension. Propranolol seems to be an effective modality of treatment for periocular IH. It seems to be most efficacious when initiated in the proliferative phase of IH but may be beneficial even in the later stage. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Assessing amblyogenic factors in 100 patients with congenital ptosis.

To study the frequency of amblyogenic factors in patients with congenital ptosis. In this cross-sectional study, 114 eyes of 100 patients with congenital ptosis more than 1 year old were included. Amblyopia was defined as best-corrected visual acuity (BCVA) less than 10/10 or a difference between the two eyes of at least 2/10. In patients too young to be measured by the linear Snellen E test, fixation behavior was observed. Different types of amblyopia were assessed for each patient as: 1) anisometropic amblyopia: astigmatic anisometropia ≥1 dpt, hyperopic spherical anisometropia ≥1 dpt, myopic spherical anisometropia ≥-3 dpt (with cycloplegia); 2) strabismic amblyopia, and 3) stimulus deprivation amblyopia (SDA). Then the total incidence of amblyopia and each type of it were obtained. Patients with uni- and bi-lateral ptosis were also compared. The incidence of amblyopia in ptotic eyes was 39/114 (34.2 %), and for each specific cause was: refractive amblyopia in 29.8%, SDA in 10.5%, strabismic amblyopia in 4.3%. Amblyopia was more frequent in severe ptosis, 76% in patients with covered optical axes (OA), compared to non-covered OA (22.5%). In unilateral ptosis with covered OA, astigmatic anisometropic amblyopia was more frequent, and in bilateral ptosis with at least one eye covered OA, spherical anisometropic amblyopia was more frequent. In both unilateral and bilateral ptosis, SDA was more common if the OA was covered. As refractive anisometropic amblyopia is more prevalent than SDA, paying attention to all causes of amblyopia may be important in preventing amblyopia in a child with a ptotic eye.

Prevalence of Amblyopia and Strabismus in Young Singaporean Chinese Children

PURPOSE. To determine the prevalence of amblyopia and strabismus in young Singaporean Chinese children. METHODS. Enrolled in the study were 3009 Singaporean children, aged 6 to 72 months. All underwent complete eye examinations and cycloplegic refraction. Visual acuity (VA) was measured with a logMAR chart when possible and the Sheridan-Gardner test when not. Strabismus was defined as any manifest tropia. Unilateral amblyopia was defined as a 2-line difference between eyes with VA < 20/30 in the worse eye and with coexisting anisometropia (> or =1.00 D for hyperopia, > or =3.00 D for myopia, and > or =1.50 D for astigmatism), strabismus, or past or present visual axis obstruction. Bilateral amblyopia was defined as VA in both eyes <20/40 (in children 48-72 months) and <20/50 (<48 months), with coexisting hyperopia > or =4.00 D, myopia < or = -6.00 D, and astigmatism > or =2.50 D, or past or present visual axis obstruction. RESULTS. The amblyopia prevalence in children aged 30 to 72 months was 1.19% (95% confidence interval [CI], 0.73-1.83) with no age (P = 0.37) or sex (P = 0.22) differences. Unilateral amblyopia (0.83%) was twice as frequent as bilateral amblyopia (0.36%). The most frequent causes of amblyopia were refractive error (85%) and strabismus (15%); anisometropic astigmatism >1.50 D (42%) and isometropic astigmatism >2.50 D (29%) were frequent refractive errors. The prevalence of strabismus in children aged 6 to 72 months was 0.80% (95% CI, 0.51-1.19), with no sex (P = 0.52) or age (P = 0.08) effects. The exotropia-esotropia ratio was 7:1, with most exotropia being intermittent (63%). Of children with amblyopia, 15.0% had strabismus, whereas 12.5% of children with strabismus had amblyopia. CONCLUSIONS. The prevalence of amblyopia was similar, whereas the prevalence of strabismus was lower than in other populations.

Anisometropia Prevalence in a Highly Astigmatic School-Aged Population

To describe prevalence of anisometropia, defined in terms of both sphere and cylinder, examined cross-sectionally, in school-aged members of a Native American tribe with a high prevalence of astigmatism. Cycloplegic autorefraction measurements, confirmed by retinoscopy and, when possible, by subjective refraction were obtained from 1041 Tohono O'odham children, 4 to 13 years of age. Astigmatism > or =1.00 diopter (D) was present in one or both eyes of 462 children (44.4%). Anisometropia > or =1.00 D spherical equivalent (SE) was found in 70 children (6.7%), and anisometropia > or =1.00 D cylinder was found in 156 children (15.0%). Prevalence of anisometropia did not vary significantly with age or gender. Overall prevalence of significant anisometropia was 18.1% for a difference between eyes > or =1.00 D SE or cylinder. Vector analysis of between-eye differences showed a prevalence of significant anisometropia of 25.3% for one type of vector notation (difference between eyes > or =1.00 D for M and/or > or =0.50 D for J0 or J45), and 16.2% for a second type of vector notation (between-eye vector dioptric difference > or =1.41). Prevalence of SE anisometropia is similar to that reported for other school-aged populations. However, prevalence of astigmatic anisometropia is higher than that reported for other school-aged populations.

Treatment of capillary hemangiomas causing refractive and occlusional amblyopia

Capillary hemangiomas of the eyelid and orbit are treated when amblyopia secondary to anisometropic astigmatism or pupillary occlusion is present or when rapid growth of the hemangioma threatens to occlude the pupil. The goal of this study was to determine whether treatment of hemangiomas resolves or prevents occlusion or results in decrease in astigmatism. The records of 54 patients who underwent treatment for reduction in the size of a capillary hemangioma causing amblyopia or threatened amblyopia in two pediatric ophthalmology practices were reviewed. Twenty-eight patients were treated for amblyopia due to anisometropic astigmatism. The average amount of pretreatment astigmatism was 2.71 D, while the average amount of post-treatment astigmatism was 0.46 D. Fifteen of these patients could be tested for optotype visual acuity and all had vision acuity of 20/40 or better. Only 1 of the 15 patients treated for threatened occlusion of the pupil developed occlusion. Six of these patients cooperated with optotype visual acuity and all had vision acuity of 20/30 or better. Eleven patients were treated for pupillary occlusion. Occlusion resolved in all cases. Of the five patients treated for occlusion who cooperated with optotype visual acuity, two had a vision acuity of 20/100 or worse. Treatment to reduce the size of capillary hemangiomas results in resolution of occlusion, reduction in astigmatism, and prevention of pupillary occlusion. Those with occlusion are at higher risk for severe residual amblyopia and require prompt and definitive treatment.

Reappraisal of Astigmatism Induced by Periocular Capillary Hemangioma and Treatment with Intralesional Corticosteroid Injection

To document refractive status and visual acuity before and after intralesional corticosteroid injection in children with astigmatism induced by periocular capillary hemangioma (PCH). Retrospective, interocular comparison, interventional case series. Thirteen infants with anisometropic astigmatism of at least 1.50 diopters (D) induced by PCH. All infants had one or more intralesional corticosteroid injections of a PCH between 2 and 10 months of age. Injections of 0.3 to 1.0 ml of a 50:50 mixture of triamcinolone (40 mg/ml) and dexamethasone phosphate (4 mg/ml) were given at a single site under deep sedation. Refraction and acuity using Teller acuity cards before and after injection. In affected eyes, mean astigmatisms were 3.75 D (pretreatment) and 1.25 D (posttreatment), and mean spherical errors were 0.75 D (pretreatment) and 1.50 D (posttreatment). Reduction in astigmatism was observed within 1 to 14 months after the injection. Despite reciprocal changes in astigmatism and spherical error, the amount of anisometropia (spherical equivalent) remained constant. Amblyopia was not observed before treatment and was observed in only 2 of 13 children after treatment. Complications were limited to adrenal suppression with transient reductions of linear growth and localized eyelid necrosis. Intralesional corticosteroid injections given in infancy (between 2 and 10 months) resulted in a 63% reduction in the mean amount of astigmatism induced by PCH. The reciprocal changes of astigmatism and spherical error without changes in anisometropia suggest that the treatment effect was due to restoration of the spherical shape of the cornea. Before 3 years of age, visual immaturity exceeded the optical blur related to astigmatism induced by PCH. Therefore, astigmatism, not anisometropia or amblyopia, is the immediate indication for treatment of PCH with intralesional corticosteroids. Injection of corticosteroid at a single site minimizes the potential for severe ocular complications owing to tissue pressure and tumor volume considerations.

Topography-guided customized laser-assisted subepithelial keratectomy for the treatment of postkeratoplasty astigmatism

To assess topography-assisted corneal wavefront excimer laser surface ablation for the correction of ametropia and irregular astigmatism after keratoplasty. Department of Ophthalmology, St. Thomas' Hospital, London, United Kingdom. In this pilot study, 15 patients (16 eyes) who were intolerant of spectacle and contact lens correction due to astigmatic anisometropia after keratoplasty (15 penetrating and 1 lamellar) had topography-assisted customized excimer laser treatments. Corneal topographic data using a Keratron Scout, Placido disk system allowed for preoperative analysis of wavefront anomalies of the anterior corneal surface from which a customized excimer laser correction of both lower-order aberrations (LOAs) and higher-order aberrations (HOAs) was prepared (ORK software) for treatment with a Schwind Esiris flying-spot laser. All eyes had laser-assisted subepithelial keratectomy (LASEK) using 15% alcohol with a 20-second to 30-second application. Four eyes received an application of mitomycin-C (MMC) 0.2 mg/mL for 1 minute after stromal ablation. The mean preoperative spherical equivalent (SE) was -3.50 diopters (D) +/- 3.97 (SD) (range +1.625 to -9.25 D). The preoperative cylindrical error was -7.2 D (range -2.75 to -13.5 D). The programmed laser correction was -3.14 D (range +1.62 to -9 D) with a maximum attempted cylindrical correction of -7 D. Adherent LASEK epithelial flaps along suture lines and the graft-host junction were noted in 9 eyes (56%), although it was possible to obtain and replace a partial flap. A follow-up of 18 months was achieved in all eyes. At the final follow-up visit, the mean postoperative SE was -1.08 +/- 1.85 D (range +3 to -4.78 D) (P<.01, F<.01). Ten eyes (62.5%) were within +/-1 D of the intended correction. The mean postoperative cylindrical error was -2.72 D (range -0.5 to -6.5 D) (P<.001), with vector analysis demonstrating a mean 6.23 D correction. Analysis of HOAs using a 6.0 mm pupil size demonstrated a significant reduction of higher-order root mean square (RMS) (P<.002), trefoil (P<.005), and 4th-order spherical aberration (P<.02) at 18 months compared with preoperative values. Uncorrected visual acuity improved in all eyes (P<.0001). Best spectacle-corrected visual acuity was unchanged or improved in 13 eyes (81%) and worse in 2 eyes by 1 line; 1 eye lost 3 lines due to an increase in preexisting cataract. In eyes that did not receive MMC, corneal haze (grade II to IV) was encountered in 3 eyes (27%). One eye required phototherapeutic keratectomy with MMC application at 12 months. Of the 4 eyes treated with MMC, 1 had trace haze and 3 had no detectable haze. There were no reported cases of epithelial instability, ectasia, or graft rejection. Topography-assisted customized LASEK was effective in the correction of postkeratoplasty astigmatism. A significant improvement of both LOAs and HOAs was obtained with good refractive stability for over 18 months. Iatrogenic haze typically occurred but appeared to be minimized with adjunctive use of intraoperative MMC.

Does Treatment of Capillary Hemangiomas for Amblyogenic Factors Result in a Resolution of the Amblyogenic Factors?

Factors Result in a Resolution of the Amblyogenic Factors? Shirah R. Schwartz, MD, Francine Blei, MD, Emily Ceisler, MD, Mark Steele, MD, Louis Furlan, MD, Sylvia R. Kodsi, MD; North Shore–Long Island Jewish Health System, Great Neck, NY Introduction: Treatment of capillary hemangiomas is initiated when there is amblyogenic anisometropic astigmatism, when there is pupillary occlusion, or when rapid growth of the hemangioma threatens to occlude the pupil. The goal of this study was to determine whether treatment of hemangiomas results in resolution or prevention of occlusion or decrease of astigmatism. Methods: The records of 55 patients who underwent treatment for reduction in size of a capillary hemangioma in two pediatric ophthalmology practices were reviewed. Indication for treatment, age at first visit, cycloplegic refraction at the initial and final visits, type of treatment, need for patching or spectacles, and final visual acuity were recorded. Results: This is the largest case series of children with capillary hemangiomas with recorded pretreatment and posttreatment cycloplegic refraction who were followed through the duration of treatment. Twelve patients were treated for pupillary occlusion. Occlusion resolved in all cases. Of the six patients with a final measurable visual acuity (FMVA), two had a vision of 20/100 or worse. Thirty patients were treated for anisometropic astigmatism. The average amount of pretreatment astigmatism was 2.68 D, while the average amount of posttreatment astigmatism was 0.53 D. All 15 patients with an FMVA had a vision of 20/40 or better. The 13 patients treated for threatened occlusion of the visual axis did not develop occlusion. The six patients with a FMVA all had vision of 20/30 or better. Conclusion: Treatment to reduce the size of capillary hemangiomas results in resolution of occlusion, reduction in astigmatism, and prevention of pupillary occlusion. Those with occlusion are at higher risk for severe residual amblyopia and require more aggressive treatment.

Prescribing Eyeglass Correction for Astigmatism in Infancy and Early Childhood: A Survey of AAPOS Members

To determine prescribing practices of pediatric ophthalmologists for astigmatism and astigmatic anisometropia in infants and young children. A survey was sent to the 700 North American AAPOS members listed in the 2004 web site directory. A total of 412/700 surveys (59%) were returned. The level of astigmatism at which pediatric ophthalmologists prescribe eyeglasses for astigmatism varies considerably across the age range from birth to 3 years. The level at which 50% would prescribe glasses was > or =4.00 D from 0 to <6 months and decreased to > or =2.00 D by 2 to <3 years. Furthermore, one-fifth indicated that they would not prescribe eyeglasses for astigmatism in infants <6 months of age. Prescribing practices for astigmatic anisometropia were slightly less variable across age, with 50% of respondents indicating that they would prescribe eyeglasses for astigmatic anisometropia > or =3.00 D from 0 to <6 months, decreasing to > or =1.50 D by 2 to <3 years. The American Academy of Ophthalmology Preferred Practice Patterns guidelines accurately reflect prescribing practices of pediatric ophthalmologists for 1- and 2-year-old children for bilateral astigmatism and astigmatic anisometropia. However, the AAO guidelines do not accurately reflect the prescribing practices for children in the 0 to <1-year age range. For children 0 to <6 months of age, pediatric ophthalmologists indicate that they typically require a higher amount of astigmatism or astigmatic anisometropia than that recommended by the AAO guidelines, or they do not prescribe glasses at all.

Fitting contact lenses for visual rehabilitation after penetrating keratoplasty.

To determine the optical indications for contact lens wear after corneal transplantation. The type of lenses used, fitting philosophy, visual outcomes, and complications were examined. A 4-year retrospective chart review was performed and identified 35 eyes in 30 patients wearing contact lenses for visual rehabilitation after penetrating keratoplasty. The optical indications for contact lens fitting after penetrating keratoplasty were multifactorial and included irregular astigmatism (62.9%), spherical anisometropia (57.1%), and astigmatic anisometropia (54.3%). The average time from surgery to initial contact lens fitting was 18.2 months. Spherical rigid gas-permeable lenses were the most common type of lens used. The mean best-corrected visual acuity improved from less than 20/40 with spectacles alone to better than 20/30 when using a contact lens. Punctal occlusion and lubrication helped to improve contact lens tolerance. Complications associated with contact lens use tended to be minor and responded generally well to conservative treatment measures. Contact lenses can improve visual function in patients with irregular astigmatism and anisometropia after penetrating keratoplasty.

A longitudinal study of cycloplegic refraction in a cohort of 350 Japanese schoolchildren. Anisometropia

The intereye difference of cycloplegic refraction was determined in a cohort of 350 rural Japanese schoolchildren aged 6 to 11 years. The intereye spherical difference remained statistically unchanged throughout 5 years, with mean value ranging from 0.21 to 0.28 D, median from 0.15 to 0.20 D, and the 95th percentile from 0.58 to 0.85 D. The prevalence of 1.0 D or greater spherical anisometropia was up to 3.1%. Linear regression analyses of the longitudinal data from individual children revealed that 295 (84.3%) children had remained unchanged while 55 (15.7%) showed significant increase or decrease in the amount of anisometropia with increasing age. The intereye astigmatic difference was also statistically unchangeable, with mean value ranging from 0.28 to 0.36 D, median from 0.20 to 0.39 D, and the 95th percentile from 0.70 to 0.90 D. The prevalence of 1.0 D or greater astigmatic anisometropia was up to 4.3%. There was a significant correlation between the spherical and astigmatic anisometropia. The results show the current state of intereye refractive difference in Japanese schoolchildren, demonstrating that it remains unchanged and significant anisometropia is rare during school age.

A longitudinal study of cycloplegic refraction in a cohort of 350 Japanese schoolchildren. Anisometropia.

The intereye difference of cycloplegic refraction was determined in a cohort of 350 rural Japanese schoolchildren aged 6 to 11 years. The intereye spherical difference remained statistically unchanged throughout 5 years, with mean value ranging from 0.21 to 0.28 D, median from 0.15 to 0.20 D, and the 95th percentile from 0.58 to 0.85 D. The prevalence of 1.0 D or greater spherical anisometropia was up to 3.1%. Linear regression analyses of the longitudinal data from individual children revealed that 295 (84.3%) children and remained unchanged while 55 (15.7%) showed significant increase or decrease in the amount of anisometropia with increasing age. The intereye astigmatic difference was also statistically unchangeable, with mean value ranging from 0.28 to 0.36 D, median from 0.20 to 0.39 D, and the 95th percentile from 0.70 to 0.90 D. The prevalence of 1.0 D or greater astigmatic anisometropia was up to 4.3%. There was a significant correlation between the spherical and astigmatic anisometropia. The results show the current state of intereye refractive difference in Japanese schoolchildren, demonstrating that it remains unchanged and significant anisometropia is rare during school age.

Anisometropic Amblyopia

One hundred twenty-four patients with anisometropia of 1 diopter or greater and amblyopia were reviewed as to the type and amount of anisometropia, whether or not they had consulted with an ophthalmologist, visual acuity before and after treatment, and type of treatment. The patient population was divided into five groups according to the type of anisometropia. Eighty-two percent of all patients reached a visual acuity of 20/40 or better. Eighteen percent of all patients reached a visual acuity of 20/20. The best visual acuity obtained was not found to be related to the degree of anisometropia or the age at which treatment was begun. Patients with myopic and compound myopic astigmatism/mixed astigmatism anisometropia had poorer visual outcomes. There was a strong positive correlation between the initial visual acuity and the best visual acuity obtained (P = 0.0001).

Die Refraktion im 1. Lebensjahr und die Entwicklung des Astigmatismus

Retinoscopy was performed in 205 children under atropine cycloplegia during the first year of life. In 22% an astigmatism (minimum 1.0 D) was found with a small peak of incidence between the 31st and 40th week. In a follow-up study (45 children) the incidence and degree of astigmatism were found to increase slightly. During the first 3 years of life esotropic children developed an astigmatic anisometropia (minimum 1.0 D difference in the astigmatism of the two eyes) more frequently the non-esotropic children. The hypothesis that astigmatic anisometropia is produced by visual deprivation in esotropic individuals is discussed.

Meridional Scotomas in Patients with Anisometropic Astigmatism

Meridional Scotomas in Patients with Anisometropic Astigmatism