Sir,

We read with great interest the recent article by Bonaparte et al1 regarding the visual acuity and its predictors after surgery for bilateral cataracts in children. We would like to make the following comments on this article.

The mainstream study supported that timely cataract surgery in infants decreases the risk of developing resistance to amblyopia treatment and increases optimal potential visual functions. However, Bonaparte proposed that age <1 year at the time of cataract extraction was associated with poor postoperative visual acuity. Several reasons may account for this discrepancy. First, the majority of the patients having cataract extraction <1 year are more likely to have severe cataract types (for example, total cataract, diffuse cataract). These types of cataract occur during infancy, which is the sensitive and critical stage in visual development causing high risk of amblyopia.2 Therefore, the types of cataract instead of the surgical timing might be the underlying mechanism for the poorer vision among individuals who underwent cataract extraction at age <1 year. Meanwhile, recent studies have demonstrated that early cataract surgery is associated with high risk of secondary glaucoma and severe posterior capsular opacification.3 These potential postoperative factors might be another important reason for the poor vision among patients with early cataract surgery.

This study also reported that absence of primary IOL placement is associated with poor postoperative visual acuity. We suggest that these results should be interpreted cautiously. Children born with visually significant cataract tend to have earlier surgery, leading absence of primary IOL placement because of their overall less developed eyes. The aphakic infants will suffer from higher risk of secondary glaucoma, causing poorer vision.4 The patients with developmental cataracts will have later surgery with primary IOL placement. It would be better to put the type of cataract, surgical timing, and IOL implantation together to see their interrelationship with long-term visual acuity. We presume that the occurrence of primary IOL implantation is highly correlated with the surgical timing and thus will affect the visual prognosis.

We sincerely appreciate Bonaparte and colleagues for their remarkable contributions to the study of preoperative predictors for pediatric cataracts. However, the conclusion might be more powerful and valuable for uncovering the underlying relationship between related factors and visual acuity if the study could further consider the types of cataract and postoperative factors.