Macular thickness and amblyopia.

PURPOSE: To compare macular thickness in children with functional amblyopia and those without amblyopia using optical coherence tomography (OCT). METHODS: This case-control study was conducted on 93 children aged 3-10 years including 44 cases with unilateral amblyopia and 49 subjects without amblyopia. Amblyopic eyes were considered as the case group and their fellow eyes as internal controls; eyes of non-amblyopic children served as the external control. Macular thickness of all eyes were measured by optical coherence tomography in the center (foveola), 1 mm ring (fovea), and 3 and 6 mm rings and compared. RESULTS: Although macular thickness was generally not different between the study groups, there was a significant difference in central macular thickness between eyes with moderate to severe amblyopia and the external controls (P = 0.037). Foveal thickness difference exceeding 10 microns between fellow eyes was detected in a larger number of amblyopic children as compared to non-amblyopic controls (P = 0.002). Mean foveal thickness was greater in boys (P = 0.037) but there was no significant difference in foveal thickness among various types of refractive errors. CONCLUSION: Although there was no significant relationship between macular thickness and amblyopia, foveolar thickness in eyes with moderate to severe amblyopia was significantly greater than the external controls. Further studies with more cases of moderate to severe amblyopia are recommended.

Hypotropic dissociated vertical deviation; a case report.

PURPOSE: To report the clinical features of a rare case of hypotropic dissociated vertical deviation (DVD). CASE REPORT: A 25-year-old female was referred with unilateral esotropia, hypotropia and slow variable downward drift in her left eye. She had history of esotropia since she had been 3-4 months of age. Best corrected visual acuity was 20/20 in her right eye and 20/40 in the left one when hyperopia was corrected. She underwent bimedial rectus muscle recession of 5.25mm for 45 prism diopters (PDs) of esotropia. She was orthophoric 3 months after surgery and no further operation was planned for correction of the hypotropic DVD. CONCLUSION: This rare case of hypotropic DVD showed only mild amblyopia in her non-fixating eye. The etiology was most probably acquired considering hyperopia as a sign of early onset accommodative esotropia.

Surgical results of consecutive exotropia.

PURPOSE: To determine the success rates of different surgical procedures and the risk factors of surgical failure among patients with consecutive exotropia. METHODS: Forty patients with exotropia were observed at least 6 weeks after their esotropia surgery. Surgical planning was based on the medial rectus muscle function. Lateral rectus weakening in patients with normal medial rectus function, medial rectus strengthening for patients with limited medial rectus function (-1 to -3), and combined procedure occurred when the correction of each type of surgery was less than the amount of deviation. Postoperatively, patients were divided into success (8 prism diopters [PD] or less) or failure (8 PD or greater) groups. The follow-up period was at least 3 months. RESULTS: The mean preoperative exotropia was 29 ± 13 PD, which was reduced to 7 ± 7 PD postoperatively (P < .001). Successful results were achieved in 31 patients (77.5%), 17 (81%) in lateral rectus weakening, 10 (83%) in medial rectus strengthening, and 4 (57%) in the combined procedure group. More preoperative exodeviation was observed in the failure group compared to the success group (P = .015).The mean dose response was 2.27 ± 0.92 PD/mm in the lateral rectus weakening, 4.25 ± 2.27 PD/mm in the medial rectus strengthening, and 2.31 ± 0.66 PD/mm in the combined procedure groups. CONCLUSION: If the choice of surgical planning is based on medial rectus function and the amount of exodeviation, satisfactory alignment would be achieved in the majority of patients with consecutive exotropia. The preoperative amount of exodeviation was the only risk factor of surgical failure in the study.

The prevalence of reoperation and related risk factors among patients with congenital esotropia.

PURPOSE: To determine the prevalence rate and related risk factors of reoperation among patients with congenital esotropia. METHODS: One hundred fifty-seven children with congenital esotropia were divided into two groups after at least one operation: children with deviation within 10 PD (n = 89; success group) and those with deviation greater than 10 PD or history of reoperation (n = 68; failure group). The relationship of risk factors such as age at first operation and primary congenital esotropia of less than 30 or more than 50 PD and accompanying factors such as inferior oblique muscle overaction (> +1), dissociated vertical deviation, lateral rectus muscle underaction, and A-V pattern with reoperation were studied. Final sensory status of children 5 years and older was evaluated by Worth 4-dot and Titmus tests. RESULTS: Reoperation was indicated in 32.4% of children who had residual esotropia greater than 15 PD after 3 months following their first operation. Congenital esotropia greater than 30 PD (P = .002) and lateral rectus muscle underaction of −1 to −2 (P < .005), were statistically different between the two groups. Initial operation at younger than 3 years was more likely to achieve gross stereopsis in children 5 years and older (P = .032). CONCLUSION: Congenital esotropia greater than 30 PD and lateral rectus muscle underaction were found to be risk factors of reoperation.