The Relationship between Higher-order Aberrations and Amblyopia Treatment in Hyperopic Anisometropic Amblyopia

PURPOSE: To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia. METHODS: The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia treatment, patients were divided into two groups: treatment successes and failures. Using the degree of spherical anisometropia, subjects were categorized into mild, moderate, or severe groups. Ocular, corneal, and internal HOAs were measured using a KR-1W aberrometer at the initial visit, and at 3-month, 6-month, and 12-month follow-ups. RESULTS: The results of the 45 (21 males and 24 females) hyperopic anisometropic amblyopia patients who completed the 12-month follow-up examinations were analyzed. The mean patient age at the initial visit was 70.3 months. In total, 28 patients (62.2%) had successful amblyopia treatments and 17 patients (37.8%) failed treatment after 12 months. Among the patient population, 24 (53.3%) had mild hyperopic anisometropia and 21 (46.7%) had moderate hyperopic anisometropia. When comparing the two groups (i.e., the success and failure groups), ocular spherical aberrations and internal spherical aberrations in the amblyopic eyes were significantly higher in the failure group at every follow-up point. There were no significant differences in any of the HOAs between mild and moderate cases of hyperopic anisometropia at any follow-up. When the amblyopic and fellow eyes were compared between the groups there were no significant differences in any of the HOAs. CONCLUSIONS: HOAs, particularly ocular spherical aberrations and internal spherical aberrations, should be considered as reasons for failed amblyopia treatment.

The Relationship between Higher-order Aberrations and Amblyopia Treatment in Hyperopic Anisometropic Amblyopia

PURPOSE: To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia. METHODS: The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia treatment, patients were divided into two groups: treatment successes and failures. Using the degree of spherical anisometropia, subjects were categorized into mild, moderate, or severe groups. Ocular, corneal, and internal HOAs were measured using a KR-1W aberrometer at the initial visit, and at 3-month, 6-month, and 12-month follow-ups. RESULTS: The results of the 45 (21 males and 24 females) hyperopic anisometropic amblyopia patients who completed the 12-month follow-up examinations were analyzed. The mean patient age at the initial visit was 70.3 months. In total, 28 patients (62.2%) had successful amblyopia treatments and 17 patients (37.8%) failed treatment after 12 months. Among the patient population, 24 (53.3%) had mild hyperopic anisometropia and 21 (46.7%) had moderate hyperopic anisometropia. When comparing the two groups (i.e., the success and failure groups), ocular spherical aberrations and internal spherical aberrations in the amblyopic eyes were significantly higher in the failure group at every follow-up point. There were no significant differences in any of the HOAs between mild and moderate cases of hyperopic anisometropia at any follow-up. When the amblyopic and fellow eyes were compared between the groups there were no significant differences in any of the HOAs. CONCLUSIONS: HOAs, particularly ocular spherical aberrations and internal spherical aberrations, should be considered as reasons for failed amblyopia treatment.

Ocular aberrations in amblyopic children

To study the pattern of ocular aberrations in amblyopic children, and evaluate a possible relation to etiology and treatment outcomes of amblyopia. The WaveScan Wavefront System [AMO, Santa Ana, CA, USA] aberrometer was used to assess 75 eyes [60 children] after instillation of 1% cyclopentolate eyedrops. There were 29 males and 31 females with a mean age of 9.23 +/- 2.55 years [range, 5-14 years]. The study sample was subdivided into four groups; 16 emmetropic non-amblyopic eyes [control group]; 24 pre-treatment newly diagnosed amblyopic eyes; 16 eyes of treated amblyopes and; 19 eyes with refractory amblyopia. Amblyopes had statistically significant greater root mean square [RMS] values for whole eye aberrations, 2[nd] order aberrations, defocus [Z[0][2]] and astigmatism [Z[2][2]] compared to emmetropes [P < 0.0001]. The refractory amblyopic group showed statistically significant differences in whole eye RMS, 2[nd] order- aberrations, defocus [Z[0][2]] and astigmatism [Z[2][2]] when compared to treated amblyopic groups [P < 0.0001]. Apart from a statistically significant difference in 5[th] order RMS of pre-treated amblyopes versus the control group, no other significant differences were found in higher order aberrations [HOAs: coma, spherical, higher-order astigmatism, trefoil, or 3[rd], 4[th], 5[th] or 6[th] order terms] between emmetropes and any of the amblyopic groups. Lower order aberrations remain the major factor that affect retinal image quality and hence amblyopia development especially in ametropic eyes. This can be corrected optically. Studying HOA profile in amblyopic eyes failed to explain why refractory amblyopia does not respond to orthoptic treatments. This outcome indicates that theories of central problems in image processing and binocular interaction are likely the main cause of refractory amblyopia.

The Correlation of Differences in the Ocular Component Values with the Degree of Myopic Anisometropia

PURPOSE: To determine the relationship between the differences in the ocular component values with the degree of anisomyopia. METHODS: Refraction, corneal power (CP), and biometry were examined in 50 myopic adults with refractive differences (RD) over 1.50 diopters (D). Ocular components were measured by ultrasound biometry and keratometry. The correlation between the differences in the ocular component values with the degree of anisomyopia was analyzed by linear regression analysis. RESULTS: Among 50 adults with anisomyopia, 5 had RD from 1.50 to 2.99 D, 11 had RD from 3.00 to 3.99 D, 9 had RD from 4.00 to 5.99 D, 12 had RD from 6.00 to 7.99 D, 7 had RD from 8.00 to 11.99 D, and 6 had > or =12.00 D. There was no significant correlation between the ocular components (CP, crystalline lens thickness [LT], and anterior chamber depth [ACD], and the length from the cornea to the posterior surface of the lens [ACD + LT]) and the RD (p > 0.05). The RD showed a significantly positive correlation with vitreous chamber depth (VCD), and axial length (r = 0.963, p < 0.0001). CONCLUSIONS: The severity of anisomyopia was not correlated with the between-eye differences in the anterior chamber values of the eye (CP, ACD, LT, ACD + LT). The severity of anisomyopia was significantly correlated with the between-eye differences in VCD.

Thicknesses of Macular Retinal Layer and Peripapillary Retinal Nerve Fiber Layer in Patients with Hyperopic Anisometropic Amblyopia

This prospective study was performed to measure the macular and the peripapillary retinal nerve fiber layer (RNFL) thicknesses using optical coherence tomography (OCT) in patients with anisometropic amblyopia. Thirty-one patients with hyperopic anisometropic amblyopia were included. The macular retinal thickness and the peripapillary RNFL thickness were measured using OCT. The mean refractive error was +3.71 diopters (D) and +1.00 D, the mean macular retinal thickness was 252.5 micrometer and 249.7 micrometer, and the mean RNFL thickness was 115.2 micrometer and 109.6 micrometer, in the amblyopic eye and the normal eye, respectively. OCT assessment of RNFL thickness revealed a significantly thicker RNFL in hyperopic anisometropic amblyopia (P=0.019), but no statistically significant difference was found in macular retinal thickness (P> 0.05). In conclusion, the amblyopic process may involve the peripapillary RNFL, but not the macula. However, further evaluation is needed.

Resultados do tratamento da ambliopia com levodopa combinada à oclusão / Results of amblyopia treatment with levodopa associated with occlusion therapy

OBJETIVO: Verificar a melhora da acuidade visual com levodopa/benzerazida combinada à oclusão parcial e seguida por oclusão total, em pacientes com ambliopia considerada irreversível. MÉTODOS: Realizou-se estudo experimental aberto, envolvendo 37 pacientes entre 7 e 40 anos de idade, com ambliopia por estrabismo ou anisometropia, durante 9 semanas. Todos os pacientes foram tratados com levodopa (0,70 mg/kg/dia) e benzerazida 25 por cento associada à oclusão de 4 horas/dia do olho dominante por 5 semanas e, nas 4 semanas seguintes foi realizada somente a oclusão total (24 h) do olho dominante. A acuidade visual foi medida na tabela do ETDR (Early Treatment Diabetic Retinopathy) com escala logMAR (logaritmo do mínimo ângulo de resolução) antes de iniciar o tratamento e após 1, 3, 5 e 9 semanas de tratamento. As adesões ao tratamento de oclusão e a ingesta do me-dicamento foram verificadas por meio de questionário e pela contagem das cápsulas. Os efeitos adversos foram avaliados por exame clínico e questionário. RESULTADOS: Após 9 semanas de tratamento, a acuidade visual média melhorou em logMAR de 0,58 ± 0,16 para 0,23 ± 0,16 (melhora de 4 linhas na tabela ETDR). CONCLUSAO: Levodopa, na dose de 0,70 mg/kg/dia, é bem tolerada e associada à oclusão produz melhora significativa na acuidade visual de pacientes com ambliopia considerada irreversível.

The effect of anisometropia on binocular visual function.

PURPOSE: To investigate the effects of anisometropia on binocular vision. METHODS: One to three dioptres of unilateral hyperopia, myopia or astigmatism was induced in 30 normal adults. The effect on binocularity was assessed with the Worth-four dot test, Titmus stereo test and Bagolini's lenses. RESULTS: Binocular vision deteriorated with increasing anisometropia. Spherical anisometropia was more deleterious than astigmatic anisometropia. CONCLUSION: In addition to amblyopia, the potential effect of anisometropia on binocular vision should be considered while prescribing spectacles in young children during the sensitive period.

Cirurgia refrativa no tratamento de crianças com ambliopia por anisometropia miópica; uma indicaçäo especial / Refractive surgery for amblyopia in anisometropia myopia

Foram realizadas correçöes de alta miopia, pela técnica da ceratomileusis in situ, em 10 olhos de pacientes com idade entre 6 e 16 anos, portadores de anisometropia miópica, com o objetivo de reduzir a miopia e, consequentemente, a anisometropia. O valor mediano da anisometropia. O valor mediano da anisometropia foi reduzido de 8,87D para 2,25D aos 3 meses (p=0.009); 1,0D com 1 ano (p=0,036). O equivalente esférico mediano foi reduzido de -11,44D para -1,75D com 3 meses (p=0,009); -1,88D com 1 ano (p=0,022); e -8,50D (p=0,036) no último controle pós-operatório. Foi observado melhora da acuidade visual em 71,4p/c dos pacientes com 1 ano e em 83,3p/c dos pacientes no grupo de controle mais tardio. Näo houve nenhum caso de perda da acuidade