To the Editor.
—We read with interest the article by Couch et al1 in the August 1990 issue of the Archives. It is especially important in reporting complications of surgery that one document compelling evidence that the problem was not preexisting and appropriate examinations were performed to relate the "complication" to the surgery performed.In the cases reported by Couch et al, the authors did not discuss the possibility that breakdown of a preexisting vertical phoria may have caused these patients' diplopia.2 Studies of superior oblique palsy have documented that one of the most common, if not the most common,3 causes of superior oblique palsy is congenital. One may distinguish acute from chronic palsies by review of old photographs for head tilt, measurement of vertical fusional amplitudes, and spread of comitance. In case 1, no mention is made of preexisting head tilt or vertical fusional amplitudes. The
Christmann LM, Wolin MJ. Superior Oblique Palsy as a Complication of Anterior Ethmoidal Artery Ligation?. Arch Ophthalmol. 1991;109(6):767. doi:10.1001/archopht.1991.01080060021007