Portal de Periódicos da CAPES

MONOCULAR DIPLOPIA OCCURRING IN CASES OF SQUINT

1941; BMJ; Volume: 25; Issue: 12 Linguagem: Inglês

10.1136/bjo.25.12.565

1468-2079

E. E. Cass,

Ophthalmology and Visual Health Research

MNIONOCULAR diplopia which is sometimes complained of and at other times can be evoked artificially, is found in cases of squint which have no physical defect in the lenses, corneae, pupils, retina etc., to account for this phenomenon, but have some abnormal retinal correspondence.As early as 1854, von Graefe had remarked upon the anomalous diplopia which occurred after cases of opera- tion for squint, and that in some cases the diplopia would change from moment to moment, being at times crossed and at others uncrossed.This change in the diplopia was due to the fact that in these cases which have both an abnormal and a normal corres- pondence, each retinal point has two space values according to whether the abnormal correspondence or the normal correspond- ence is being used.But it was Javal, who, due to the bringing to consciousness of the two space values simultaneously, actually noted a further stage of this phenomenon and described the first case of monocular diplopia occurring in a squinting child.His case, which he examined in 1864, was that of an alternating squint which dated from birth and had some weakness of the left external rectus.On examining the patient's binocular vision by means of a stereoscope, Javal found that he had monocular diplopia with the left eye, and concluded that the patient saw " one image in correct projection and the other image in false projection."Un- fortunately, this case, as many cases of squint do, disappeared after six weeks, and when Javal wrote to find out what had hap- pened, the patient replied that von Graefe had operated upon him and that he was now suffering from a crossed binocular diplopia.Javal, in his book on squint, quotes a few further cases of this monocular diplopia, usually associated with poor visual acuity in the squinting eye.Classen, in 1870, noted the second example and described the case of a patient aged 28 years, who had diplopia following an operation for a right convergent squint associated with amblyopia and noted that at times the diplopia was crossed and at others uncrossed.After operation, on covering the left eye and fixing with the right eye and then uncovering the left eye quickly, the patient saw three images of the light, a central clear one seen by the left eye and two faint images seen by the right eye, one on the left and one on the right of the clear image.The author, however, simply says