To the Editor.
—In his interesting article, Lessell1 found that a disproportionate number of esotropes had anomalous handedness compared with a control population. Anomalous handedness presumably reflects anomalous cerebral development, which led Lessell to comment that esotropic strabismus might be the result of maldevelopment of the visual cortex.Recent work from the University of California, San Francisco, and the Smith-Kettlewell Eye Research Foundation, San Francisco, provides physiologic support for this notion. Humans who develop esotropia in infancy have been found to have striking inversions and topographic distortions of motion processing in the visual cortex.2 The maldevelopment appears to involve both the primary visual area and the human homologue of monkey visual area MT in extrastriate cortex.3 Several lines of evidence argue that the cortical maldevelopment causes the ocular motor signs.2
Tychsen L. Visual Cortex Maldevelopment as a Cause of Esotropic Strabismus. Arch Ophthalmol. 1987;105(4):457. doi:10.1001/archopht.1987.01060040027013