DBICn 283As a contributory cause, however, it is considered that malnutrition may play a part. In Cases 29, 36, 42, and 48 unilateral optic atrophy followed a severe blow in the region of the eye concerned. In no instance was the blow sufficient to have left any radiological evidence of bony damage, nor was any ocular damage seen apart from the optic atrophy. It seems possible that where a severe concussion injury has caused damage to the optic nerve the nutritional level may be too low to repair the damage and atrophy may result.One 'of our cases (No. 46)-that of a soldier aged 37 who complained of the fairly sudden onset of blurring and dimness of vision soon after arrival in Egypt-showed points of similarity to a series of cases from the Middle East (Spillane and Scott, 1945). The majority of these cases retained good physical health, and the skin, heart, lungs, and gastro-intestinal tract were not affected. Within a year of this soldier's return to Rhodesia his vision was reduced to R. 6/36, L. 6/24. His disks showed evidence of postneuritic atrophy, no central scotoma was demonstrated, his fields being appa.ntly full, but the use of a Bjerrum screen at 2 metres was not made.There was no significant increase in the number of cases admitted towards the end of the dry season and the beginning of the rains, when food supplies became exhausted. It is at this time of the year that we see, for example, many cases of pellagra, night blindness, and scurvy.4. Exogenous Toxins Methyl alcohol, arsenic, and quinine are probably the main toxic agents with which the indigenous population may come into contact. As has already been mentioned, arsenic may play an important part after inadequate treatment of syphilis. Quinine and methyl alcohol blindness were not encountered in this series.It is possible that a native medicine-not divulged by the patient-may play a larger part than is suspected at the moment. We failed to discover any definite addicts such as the case of optic neuritis in a Qat addict in Somaliland described by Baird (1952).
SummaryFifty consecutive cases of optic atrophy in Africans from British Central Africa have been analysed. Purely ophthalmic causes, such as chorio-retinal disease with consecutive optic atrophy, and glaucomatous optic atrophy, have been excluded from the series, as the cause in these cases was not in doubt.Thirty-two of the series were found to be of the postneuritic atrophy type and 12 were of the primary optic atrophy type. Vascular and temporal atrophy made up the balance of cases.Various aetiological factors have been considered. In four patients-two of whom died-it was possible to ascribe a definite cause. Of the remainder, it was thought that syphilitic optic atrophy, but with no other neurological lesion, was a probable cause in the majority. A disorder of nutrition does not seem to be an important cause of optic atrophy in Central Africa.We wish to thank Dr. R. M. Morris for his permission to publish this paper.
