Optic nerve involvement in diabetes mellitus
Central Hospital, Dhanbad, India
A K Sinha
Eye specialist Central Hospital, Dhanbad
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Sinha A K. Optic nerve involvement in diabetes mellitus. Indian J Ophthalmol 1983;31:435-7
Although ocular complications of diabetes have been described in detail, very few reports deal with optic nerve involvement in this complex metabolic disorder & the clinical diagnosis of diabetic optic neuritis/atrophy is always tentative to some extent. The incidence of optic nerve involvement in diabetes also varies according to different authors.
Recently four cases of post neuritic optic atrophy in patients with uncontrolled diabetes were seen, and these cases surprisingly showed only mild retinopathic changes.
| Case reports|| |
Case-1: K.P., 56 was first examined in July, `78 with complaints of loss of vision in right eye. eight months back. Diabetes was diagnosed about 8 years back but recent diabetic control was poor.
The vision in Right eye was P.L. only with defective nasal projection. Right fundus showed a post neuritic optic atrophy without any significant retinopathic changes. The visual auity in left eye was 6/9 with normal fundus and visual fields
Case-2: S.K., 56 M, an old diabetic was first examined by us in Sept., 1978. with loss of vision in both the eyes since last two years. Ocular examination revealed a visual acuity of 1/60 in both the eyes with defective projection of rays in nasal and superior quadrants. The fundus examination revealed bilateral pale and atropic discs with hazy margins and marked narrowing of arteries.
Case-3: N.S., 60 M. was first examined by us in Dec. `79 because of loss of vision in both eyes since last one year. Ocular examination revealed a visual acuity of 4/60 in Rt. eye and P.L. only in Lt. eye.
Diabeteas had been diagnosed 10 years back but the patient did not cared for its control.
Fundus examination revealed post neuritic optic atrophy in both the eyes with a few pin point exudates in lower temporal area near disc. Fluorescein angiography showed marked capillary dilvtion and early extravasation of dye near optic disc.
Case-4: M.P., 55 M, was seen in April, 80 with the complaints of loss of vision in Right eye, which was aphakic. His left eye was enucleated 10 years back because of some post operative complications. The patient was known diabetic for last 12-14 years and the control was very poor and irregular.
The best corrected visual acuity was F x C. one meter Fundus examination revealed a pale and atrophic disc (post neuritic type) without any sign of diabetic retinopathy. All other investigations were normal in above cases (ocular & systemic).
The optic nerve involvement has been suggested as a specific complication of diabetes, but its nature and pathogenesis are still uncertain. Skillern and Lockhart presented a series of fourteen uncontrolled diabetics who had optic atrophy and out of these cases only two had retinopathic changes They attributed the optic nerve involvement to toxic metabolic changes, affecting patients with long standing or severe uncontrolled diabetes Waite & Beetham reported an increased incidence of toxic amblyopia in diabetics and suggested increased suceptibility of the optic nerves to inflammation in diabetes. Few report, suggest a casual relationship of optic nerve involvement in diabetes with peripheral neuropathy, but to what extent this comparison helps to elucidates the pathogenesis of diabetic optic nerve involvement has not yet been established. Observations on isolated peripheral nerve fibres from patients with diabetic neuropathy showed that there was segmental demyelination and remyelination, suggesting that the neuropathy may result from a disturbance of schwann cell metabolism. In addition, recent studies have suggested that the sotbitol pathway of glucose metabolism may play an important role in etiology of diabetic neuropathy. On the other hand, others,, have suggested that optic nerve involvementt in diabetics is due to a vascular phenomenon related to occlusion of optic nerve nutrients. Yanko et al reported six cases of uncontrolled diabetics with optic nerve involvement and mild backgroud retinopathy. They suggested that the optic nerve involvement in diabetes is the result of capillary changes in the superficial optic disc similar to changes found elsewhere in the retina as a part of the picture of diabetic retinopathy. Recently, anterior ischemic optic neuropathy (or vascular pseudopapillitis) has been linked to diabetes,,.