We read with interest the article by Scheiman et al1 entitled “A Randomized Clinical Trial of Treatments for Convergence Insufficiency in Children” in the January issue of the ARCHIVES. Scheiman and colleagues compared vision therapy/orthoptics with pencil push-ups and placebo vision therapy/orthoptics. We wish to point out that although pencil push-ups are the most frequently advised home convergence exercise, there is a lack of consensus regarding the most appropriate home-based convergence exercise. There is difference of opinion regarding the exact procedure of pencil push-ups and their effectiveness as compared with other home-based exercises. In pencil push-ups, the aim should be to increase both the phasic and tonic control of convergence. For this purpose, apart from increasing the fusional amplitude, convergence sustenance should also be stressed.2- 4 Convergence insufficiency can be confirmed by noting the near point of convergence and measuring the fusional convergence amplitude with synoptophore or prisms. A convergence sustenance of less than 30 seconds for a 10-cm fixation target is usually symptomatic. The pencil push-ups as advised in the article by Scheiman and colleagues have not stressed the role of convergence sustenance. To practice, this patient is advised not only to see the pencil tip as single at the nearest possible distance but also to maintain it as single for at least 30 to 40 seconds. During this time, the patient is required to see the distance-control target as double.
Sethi HS, Saxena R, Sharma P, Sinha A. Home Exercises for Convergence Insufficiency in Children. Arch Ophthalmol. 2006;124(2):287. doi:10.1001/archopht.124.2.287-a