We read with great interest the article published by Vasavada and associates regarding use of enoxaparin in an irrigating solution for pediatric cataract surgery. The authors showed no difference in postoperative inflammation while using this drug in children. They used this in a concentration of 40 mg in 500 mL balanced salt solution. It would be interesting to know why this specific concentration was used. Are there any guidelines for using this particular dose? Is there a relationship between dose and body weight or age of the child? It may be a possibility that the dose used was not appropriate enough to observe a beneficial response.
The authors showed that there were significant intraocular lens deposits 1 week after surgery that persisted until 3 months in both groups. The inflammatory response is so variable in the pediatric age group that using a particular strength of enoxaparin for all children is questionable.
After surgery, they used topical steroid 6 times daily for all children, regardless of age. The intraocular lens deposits may be a result of inadequate steroid use in the immediate postoperative period, particularly in very young children. We would be interested to know whether the inflammatory cell deposits occurred more frequently in the younger children or older children. Rumelt and associates showed a significant decrease in inflammation in children when this drug was used, although the mean age of children was higher in the enoxaparin group. However, the dosing schedule of topical steroids in their study was every 1 hour. In the series by Ozkurt and associates, the topical steroids were instilled 8 times daily after surgery, although the mean age of patients was much older (8.9 ± 5.9 years). The lower dosing schedule of steroids used after surgery in the study by Vasavada and associates might have resulted in enoxaparin having less effect on inflammation because it failed to overcome the additive effect of steroid use.
We believe that whether enoxaparin has a beneficial role in pediatric cataract surgery will not be clear until a proper dose-effect relationship is established. The exact concentration that should be tailored for young children, perhaps younger than 5 years versus older children, considering that the inflammatory response is more aggressive and variable in children of different age groups as compared with adults. We thank the authors for providing us with a randomized study that may pave the way for further studies in very young children and those with complicated cataracts.