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ORIGINAL ARTICLE |
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Year : 1980 | Volume
: 28
| Issue : 4 | Page : 195-200 |
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Profile of optic neuritis in Chandigarh and surrounding areas
IS Jain, VP Munjal, SP Dhir, DN Gangwar
Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh, India
Correspondence Address: I S Jain Department of Ophthalmology, Postgradute Institute of Medical Education and Research, Chandigarh-160012 India
 Source of Support: None, Conflict of Interest: None  | Check |
PMID: 7287112 
How to cite this article: Jain I S, Munjal V P, Dhir S P, Gangwar D N. Profile of optic neuritis in Chandigarh and surrounding areas. Indian J Ophthalmol 1980;28:195-200 |
Clinically optic neuritis manifests itself essentially as a loss of vision, irrespective of the ophthalmoscopic appearance of the optic disc. Signs and symptoms vary from patient to patient. The commonest single cause of optic neuritis reported in the west is multiple sclerosis, but in 30-75 % of the cases aetiology remains unknown[1],[2],[3]. It may be associated with metabolic, nutritional, infections or degenerative diseases. The prognosis of optic neuritis in general is good. It is considered that prognosis of retrobulbar neuritis is better than papillitis, unilateral better than bilateral and also depends upon the severity of the disease at the time of presentation. The aim of this study is to analyse the clinical features, aetiology and course of optic neuritis in our patients.
Materials and methods | |  |
Forty-two patients of optic neuritis seen in the Eye Department of Postgraduate Institute of Medical Education and Research, Chandigarh, were reviewed. History was noted for the mode of onset of diminution of vision, whether sudden or gradual, any association of pain in or around the eye. Clinical examination included; recording of visual acuity on the Snellen's charts, refraction and improvement with glasses, pupillary reaction, appearance of the optic disc, slit lamp biomicroscopy including examination of the fundus with the help of Goldman's three-mirror contact lens. Visual fields were charted on the Bjerrum's screen where-ever possible and the colour vision was tested on Ishihara charts in cases with good initial visual acuity. Neurological examination was done in all the cases and the relevant laboratory investigations were carried out. These cases were excluded in whom the involvement of the optic nerve was secondary to the affection of the other structures of the eye ball. All the cases were treated with oral corticosteroids with the initial dose varying from 60-80 mg. of prednisolone and subsequently the dose was tapered according to the response to the therapy. Improvement in the visual acuity, visual field and the change in colour of the disc were noted during the course of the disease. The follow-up of the cases varied from one month to six months.
Observations | |  |
Age and Sex : Out of the total 42 patients with 68 eyes involved, 28 (67%) were males and 14 (33%) females [Table - 1][Table - 2]. The commonest affected age group was between 20-40 years. (62%).
Symptoms : The commonest presenting symptom w as diminution of vision. The mode of onset varied from a sudden drop in the visual acuity reaching its lowest in few hours [19-(45%) patients] to slow onset taking more than 7 days 10 (24%) [patients]. In the rest [13 (31%) patients] the onset was moderately fast [Table - 3]. In 2 (1.7%) patients, the initial symptom was a change in the quality of vision, they complained of blurring of vision, though the visual acuity was normal. In 28. (66.7%) cases, the only complaint was diminution of vision while in the rest 14 (33.4%) cases there was history of pain or headache either preceding or associated with the on set of diminution of vision. Amongst these, five cases had pain in or around the eye ball, in other three cases the pain was localized to the temporal region, two cases had painful eye movements and in the rest 5 cases there was headache, not localized to any site. In none of the cases the pain was severe enough to disturb the sleep.
In 16 (38%) patients the disease was unilateral and in 26 (62%) it was bilateral. In 3 cases there was history and clinical evidence of the involvement of one eye in the past and they presented to us with involvement of the other eye. In 23 (54.7%) patients the onset was bilateral.
Visual Acuity : In most eyes the initial visual acuity was very poor; in 22 (32.3%) eyes is was reduced to perception of light and in 9 (13.2%) eyes even perception of light was doubtful [Table - 4] visual acuity was good (6/12 or better) only in 9 (13.2 %)eyes. Many patients came in recovery phase. Visual acuity improved to 6/ 12 or better in 30 (44%) eyes.
Pupillary Reaction : The initial pupillary reaction could be noted in 66 eyes, in one bilateral case atropine was instilled by a practicing physician before referring the case to us, so the two eyes were excluded. In 34(51.7%) eyes pupillary abnormalities were detected in the form of sluggish reaction, ill sustained reaction and fixed and dilated pupil. In the rest 32 (43.3%) eyes pupillary reaction was normal. The visual recovery in the two groups was compared after the treatment. In the first group [Table - 4] the final visual acuity of 6/ 12 or better was achieved in 4 (11.7%) eyes, whereas in the 2nd group same level was achieved in 26 (81.2%) eyes. An interesting observation was made in case No. 42, who had bilateral loss of vision, the initial visual acuity was absence of perception of light in both eyes with fixed and dilated pupils. He was treated with oral prednisolone, 80 mg. daily as the starting dose, after one week he started showing improvement in pupillary reaction and followed by improvement in visual acuity. He maintained the progress and after 3 months Visual acuity of 6/60 in the right eye and 6/36 in the left eye was achieved with pallor of the optic discs and sluggish pupillary reaction.
Optic Disc : In 20 (29.4%) eyes the appearance of the optic disc was normal, indicating retrobulbar neuritis, whereas 38 (56%) eyes showed blurring of the disc margins with or without oedema of the disc, indicating papillitis or anterior retrobulbar neuritis. In the rest 10 (15°,x) eyes discs were pale, on the first visit. [Table - 5]. One month later, out of the 61 eyes examined, 50 (82%) showed pallor of the optic disc whereas out of the 39 eyes examined 6 months later, 35 (90%) eyes showed pallor of the optic disc and 4 eyes retained normal colour.
Visual Fields : Visual fields could be done in 45 eyes and in the rest it could not be done either because of very poor vision or the patients were too young to co-operate. In some patients fields were done when they recovered some vision. The commonest field defect of concentric contraction was seen in 17 (25%) eyes. Second common defect was central scotoma observed in 13 (19.1%) eyes. other types of field defects are enumerated in [Table - 6].
Colour Vision : Colour vision was recorded in most of the cases on Ishihara charts. It was defective in cases with central scotoma or with very poor vision but in cases with good initial visual acuity, there was no defect in the colour vision. One patient had congenital colour blindness. The colour vision also recovered with the recovery of visual acuity, but in 3 cases in whom central scotoma persisted, there was no recovery of colour vision as well.
Aetiology : In 20 (47,6%) patients the aetiology remained unknown. Only 3 (7.1%) patients had some neurological deficit and a provisional diagnosis of multiple sclerosis was made. Six (14.3%) patients had consumed country liquor before the onset of the disease, other possible aetiological factors are enumerated in [Table - 7].
Discussion | |  |
Optic neuritis commonly occurs between the ages of 20 and 50 years. There is predilection for females and commonly presents with unilateral blurred vision and central scotoma. It is usually accompanied by painful movement of the eye ball and resolves with or without treatment. The commonest aetiology reported is multiple sclerosis. The proportion of first symptom of neurological disease as optic neuritis, who later develop signs of definite multiple sclerosis, lies between 11.5% and 44%[4]. Typical cases of optic neuritis due to multiple sclerosis are not commonly seen in India, only one such case has been reported by Sood et a1[5]. Most of the time diagnosis of multiple Sclerosis is presumptive[6],[7]. In our study only 3 (7.1°x) patients had clinical features on the basis of which presumptive diagnosis of multiple sclerosis was made.
The males (67%) were commonly affected than females (33%) and disease was more often bilateral (62%). In 23 (54.71%) patients the onset was bilateral whereas in the series of Eava Nikoskelainen[8] the initial attack was bilateral in 30% of the patients. In another series by Bradley and Whitty[9] only 7% of the eyes were involved simultaneously. Males pre dominate over females in bilateral cases[1],[8]. Similar observation was made in our cases [Table - 2]. Probably the aetiology is different in bilateral cases, out of the total 26 bilateral cases, in 16 (61.5%) some cause or association was found, and in 14 (53.8%) cases the cause was actual inflammation of the nerve by various agents [Table - 7].
In 51 (75%) eyes the visual acuity was reduced to C.F. less than 1 meter at the onset. An interesting observation was the correlation of the pupillary reaction and the visual recovery. In cases with normal pupillary reaction the visual recovery was faster and much more as compared to the group with abnormal pupillary reaction. It shows that damage to the nerve fibres is more severe in cases with abnormal pupillary reaction. So this is of obvious help in prognosticating the cases. There was no difference in recovery of vision in unilateral versus bilateral cases.
The other aspect of the study is the visual field defects. In typical cases of optic neuritis due to multiple sclerosis, the defects affecting the central fields are commonly seen i.e. 73%[8]. In our cases concentric contraction was the commonest field defect, this suggests that perineuritis is more common than axial neuritis in our patients and secondly the lesion is more anteriorly situated because in 38 (56%) eyes there was hyperaemia and blurring of the disc margins. Pain was not a common complaint in our patients (33.3%) and the typical pain on movement of the eye ball was seen only in two patients. Eava Nikoskelainen[8] reported that 62% of her patients had some type of pain. The pain is thought to be due to traction of the inflamed nerve by the rectus muscles or related to the inflammation or swelling in the adjacent meninges or sheaths of the optic nerve[10],[11]. The infrequent pain in our cases can be explained on the basis that the inflammation was in the anterior part of the optic nerve.
The fact that majority of the cases presented with simultaneous involvement of the both eyes, males, more frequently affected than females, papillitis more common than retrobulbar neuritis and concentric contraction of the fields as the commonest defect suggests that multiple sclerosis is not the common cause of optic neuritis in India. The other cases like metabolic, nutritional, toxic or infection should be looked for. Ischaemic optic neuropathy is a common cause of optic neuritis is elderly patients. The role of steroids therapy in typical cases of optic neuritis is controversial, there are workers for and against therapy[12]. Since multiple sclerosis is not the common aetiology in India, we feel that steroids have a definite role to play in reducing the inflammation and shortening the course of the disease and improving the final results in our cases.
Summary | |  |
Pain in the eye ball or on movement is not a common feature of optic neuritis. (7/42 cases), more than 50% cases showed bilateral onset, again contrary to established literature. Concentric contraction of fields was common fields defect indicating a perineuritis rather than axial neuritis. Multiple sclerosis is not the commonest aetiology.
References | |  |
1. | Marshall, D., 1950, Trans. Amer. Ophthalmol. Soc. 58:487. |
2. | Oksala, A., 1964, Ophthalmologica, 148: 13. |
3. | Rucker C.W. 1965, Trans, Amer Acad. Ophthalmol. Otolarying 60:93. |
4. | Editorial, Aetiology of optic Neuritis, B. Med. J., 1975, 3 (5978): 265. |
5. | Sood G.C., 1975, Ind Jour. Ophthalmol. 23 II : 20. |
6. | Bhargwa, H.S. and Berry J.N. 1961, J. Assoc. Plays. India. 9:211. |
7. | Jolly, S.S., Singh J., Singh, A., 1961, J. Assoc. Phys. India. 9:13. |
8. | Nikoskelainen Eava., 1975, Acta, Ophthalmologica, 53:254. |
9. | Bradley, W.G. and Whitty, C.W.M., 1967 J. Neurol. Neurosurgery, Psychiatry, 30:531. |
10. | Henderson J.W. 1955, Trar s. An er., Acad. Ophthalmol. Otolaryingol 60:8. |
11. | Walsh. F.B. and Hoyt, W.F., 1969, Clinical Neuro-Ophthalmology, Vol. 1, 3rd Edition, William and Wilkins, Baltimore |
12. | Helper. R.S. 1976, Surv. Ophthalmol. 20 (5); 350. |
[Table - 1], [Table - 2], [Table - 3], [Table - 4], [Table - 5], [Table - 6], [Table - 7]
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