Levodopa/Carbidopa to Augment the Treatment of Amblyopia: A Report by the American Academy of Ophthalmology.

PURPOSE: To review the published literature on the use of levodopa/carbidopa to augment the treatment of amblyopia. METHODS: Literature searches for English language studies were last conducted in October 2022 in the PubMed database with no date restrictions. The combined searches yielded 55 articles, of which 23 were reviewed in full text. Twelve of these were considered appropriate for inclusion in this assessment and were assigned a level of evidence rating by the panel methodologist. Nine studies were rated level I, and 3 studies were rated level II; there were no level III studies. RESULTS: The duration of treatment was limited to 3 to 16 weeks because of concern about long-term adverse effects such as tardive dyskinesia. This complication was not reported in any of the study participants. The dose of levodopa ranged from 1.5 to 8.3 mg/kg/day, generally divided into 3 daily doses. The carbidopa dose was approximately 25% of the levodopa dose in all treatments. Evidence from these studies indicates that augmenting traditional patch occlusion therapy with the oral administration of levodopa/carbidopa can improve the vision of amblyopic children, but the effect was small (0.17-0.3 logarithm of the minimum angle of resolution [logMAR] units) and only statistically significant when compared with patching alone in 2 of the 12 studies cited. Regression of vision was reported in the majority of studies (9 of 12 reported; range, 0-0.17 logMAR unit regression) after discontinuation of therapy. Short-term side effects of the medications were not consistently reported but were most frequently mild and included headache and nausea. CONCLUSIONS: The best available evidence is currently insufficient to show that augmenting amblyopia therapy using up to 16 weeks of levodopa/carbidopa will result in meaningful improvement in visual acuity. Given the potential for significant side effects such as tardive dyskinesia with long-term therapy, levodopa/carbidopa does not appear to be a viable option for amblyopia therapy FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Childhood amblyopia: A systematic review of recent management options.

This study reviews the current information on treatment of childhood amblyopia, with the goal of improving visual functions. The authors searched various online databases including PubMed, Web of Science, ProQuest, Scopus, Google Scholar, Ebsco, and Medline. The articles, published between 2002 and 2023, included in this study were used to assess the different modalities for the management of different types of childhood amblyopia. The final systematic review included 41 studies from different countries, covering 4060 children with a mean age 6.8 ± 124 years. The findings showed that childhood amblyopia commonly treated through a systemic approach, i.e., starting with treatment of refractive errors with given optical adaptation time, followed by visually stimulating amblyopic eye by covering the dominant eye with patching, Atropine or Bangerter filters. Refractive adaptation period of 18-22 weeks has proven to show a significant improvement in visual acuity. It has been confirmed that 2 h patching is effective for the first time treated amblyopes, and if there is no improvement, increase the period to 6 h daily. Novel methods that improve binocular function such as dichoptic, perceptual training, video gaming, and drugs that facilitate visual neuroplasticity, are useful in the treatment of amblyopia that is not responsive to conventional therapy. The study concludes that significant evidence show that childhood amblyopia is treated through a systemic approach. Starting from correcting refractive errors with a period of optical adaptation, followed by patching therapy and atropine penalization. New methods that improve the binocular functions and medications that facilitate visual neuroplasticity have found to be useful in the treatment of amblyopia that is not responsive to conventional treatment.