Amblyopia Treatment

Abstract

We read with interest the article by the Pediatric Eye Disease Investigator group concerning the role of near activities in enhancing the improvement in visual acuity while patching for amblyopia.1Pediatric Eye Disease Investigator GroupA randomized trial of near versus distance activities while patching for amblyopia in children aged 3 to less than 7 years.Ophthalmology. 2008; 115: 2071-2078Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar We seek a few clarifications regarding the methodology and conclusions. In their eligibility criteria for anisometropic amblyopia they have taken >0.50 diopters (D) difference between eyes in spherical equivalent or >1.50 D difference between eyes in astigmatism in any meridian. We would be interested to know the reason to adopt such a small difference in refraction. In the methodology, they have used calendars completed by parents to assess how many hours of patching were performed. Instead of calendars, use of electronic monitoring device (objectively monitored patching) would have been a better method to objectively monitor the patching hours.2Stewart C.E. Fielder A.R. Moseley M.J. et al.Is it all over in 6 weeks: Interim analysis of the monitored Occlusion Treatment for Amblyopia Study (MOTAS).Invest Ophthalmol Vis Sci. 2001; 42: S399PubMed Google Scholar In the conclusion, the authors have mentioned that 2 hours of patching per day is an option for the treatment of severe amblyopia. According to the article, patching hours were increased in 20 patients in the distant-activity group and 11 patients in the near-activities group. However, it is unclear if these 31 patients belonged to moderate amblyopia group or severe amblyopia group. A total of 124 children completed the 8-week follow-up visit. If all 31 patients belonged to the severe-amblyopia group, then about 25% of children did not improve with 2 hours of patching. We would be interested to know whether it is reasonable to conclude that 2 hours of patching per day is an option in the treatment of severe amblyopia. We read with interest the article by the Pediatric Eye Disease Investigator group concerning the role of near activities in enhancing the improvement in visual acuity while patching for amblyopia.1Pediatric Eye Disease Investigator GroupA randomized trial of near versus distance activities while patching for amblyopia in children aged 3 to less than 7 years.Ophthalmology. 2008; 115: 2071-2078Abstract Full Text Full Text PDF PubMed Scopus (66) Google Scholar We seek a few clarifications regarding the methodology and conclusions. In their eligibility criteria for anisometropic amblyopia they have taken >0.50 diopters (D) difference between eyes in spherical equivalent or >1.50 D difference between eyes in astigmatism in any meridian. We would be interested to know the reason to adopt such a small difference in refraction. In the methodology, they have used calendars completed by parents to assess how many hours of patching were performed. Instead of calendars, use of electronic monitoring device (objectively monitored patching) would have been a better method to objectively monitor the patching hours.2Stewart C.E. Fielder A.R. Moseley M.J. et al.Is it all over in 6 weeks: Interim analysis of the monitored Occlusion Treatment for Amblyopia Study (MOTAS).Invest Ophthalmol Vis Sci. 2001; 42: S399PubMed Google Scholar In the conclusion, the authors have mentioned that 2 hours of patching per day is an option for the treatment of severe amblyopia. According to the article, patching hours were increased in 20 patients in the distant-activity group and 11 patients in the near-activities group. However, it is unclear if these 31 patients belonged to moderate amblyopia group or severe amblyopia group. A total of 124 children completed the 8-week follow-up visit. If all 31 patients belonged to the severe-amblyopia group, then about 25% of children did not improve with 2 hours of patching. We would be interested to know whether it is reasonable to conclude that 2 hours of patching per day is an option in the treatment of severe amblyopia. Author replyOphthalmologyVol. 116Issue 8PreviewWe thank the correspondents for their interest in our article. Our classification of anisometropic amblyopia was based on exceeding a minimum level of anisometropia, the presence of an interocular visual acuity difference of 3 lines, the absence of strabismus, and the absence of any other cause of decreased visual acuity. Regardless of the threshold level of anisometropia, if all these criteria were met, the most likely cause of decreased visual acuity would still be anisometropic amblyopia. Concerning the possible use of an electronic monitoring device to record patching hours, the equipment to which the correspondents refer is not commercially available and has not yet been successfully used in large multicenter trials. Full-Text PDF