|Year : 1987 | Volume
| Issue : 4 | Page : 204-206
Exophoria and Refractive Errors- Evaluation of 250 Cases
NC Gupta, RK Narang, AK Khurana, IPS Parmar, BK Ahluwalia
|Date of Web Publication||20-Dec-2008|
N C Gupta
Source of Support: None, Conflict of Interest: None
Two hundred and fifty cases of exophoria were reviewed for the association of various refractive errors Though, myopia was the commonest association it cannot be labelled as the causative factor, because equal number of exophoria patients were emmetropic.
|How to cite this article:|
Gupta N C, Narang R K, Khurana A K, Parmar I, Ahluwalia B K. Exophoria and Refractive Errors- Evaluation of 250 Cases. Indian J Ophthalmol 1987;35:204-6
|How to cite this URL:|
Gupta N C, Narang R K, Khurana A K, Parmar I, Ahluwalia B K. Exophoria and Refractive Errors- Evaluation of 250 Cases. Indian J Ophthalmol [serial online] 1987 [cited 2020 Feb 17];35:204-6. Available from: http://www.ijo.in/text.asp?1987/35/4/204/26179
| Introduction|| |
Exophoria is a condition where in the visual axes are held in parallel position under the influence of fusion and on dissociation one eye diverges  . Wottom  stated that divergence excess type exophoria is usually due to hypermetropia Mann  found no correlation of exophoria with refractive errors Some notes have been made in the present study on the relationship of refractive errors.
| Material and Methods|| |
Two hundred and fifty cases of exophoria who attended the Orthoptic Clinic of Department of Ophthalmology were reviewed to evaluate its association with refractive errors.
| Observations|| |
Incidence of exophoria was more in females (57.6%) than males (42.4%). In both sexes it was more common in young patients below30 years of age (68.8%). Out of 250 cases only 15 (6%) had disturbing symptoms Hyperphoria was associated with exophoria in 28 cases (11.2%).
| Refractive errors and Exophoria|| |
Refractive error was detected in 142 (59.G%) cases of exophoria. Myopia was the commonest refractive error (45.2%) associated with exophoria followed byastigmatism (17.2%). [Figure 1] depicts the incidence of various refractive errors in exophoria As shown in [Table 2], amount of exophoria varied in different cases irrespective of the amount of refractive error. In other words no relation could be derived between the amount of refractive error and exophoria.
Out of 149 cases of exophoria associated with refractive errors, 26 (17.45%) became orthophoric and 16 (10.74%) showed partial improvement with corrective glasses A relief in symptoms with glasses occurred in 5 (33%) out of 15 symptomatic cases.
| Discussion|| |
An attempt has been made in the present review of 250 cases of exophoria to study the correlation between exophoria and ametropia. Adler  has suggested that presence of I to 4 prism diopters of exophoria is physiological and thus within normal limits So, only cases with exophoria of more than 4 prism diopters were included in this study.
Predilecatior of exophoria for any age and sex was analysed The overall incidence was more in females (56.6%) than males (42.4%).
Out of the 250 cases of exophoria 45.2 per cent were myopic, 40.4 per cent emmetropic, 17.2 per cent astigmatic and 14.4 per cent hypermetropic. Thus, myopia was the commonest form of ametropia associated with exophoria Dhir  in his study on myopic patients reported esophoria in 75 per cent cases As the number (40.4%) of emmetropic patients with exophoria is almost equal to myopic patients (45.2%), so it becomes difficult to blame myopia as the sole cause of exophoria Baum  also reported that myopia cannot be held responsible for exophoria Pascal  was of the view that exophoria is almost always secondary to myopia Recently Burian  stated that the role of myopia in the etiology of exodeviations is less pronounced than that of hypemietropia in esodeviations.
As regards the amount of exophoria and amount of ametropia, we could establish no relationship between the two. These observations are in accordance with those of Scober and Green . Out of 149 cases of exophoria optically corrected only 17.45 percent became orthophoric and 10.7 per cent showed partial improvement This obervation further augments the fact that refractive errors play little role in the development of exophoria. However, Marton  reported that majority of his cases of exophoria were relieved by the correction of refractive errors.[Table 1]
| References|| |
Duke-Eider, S, 1973. System of Ophthalmology, Henry Kimpton, London, Vol VI, 537-538.
Wooton, 11W., Quoted by Mann, L 1940, RJ.0., 24: 373-390.
Mann, L 1940, B.J.O., 24: 373-390.
Adler, F.H. 1970, Adlers Physiology of the Eye-Clinical application The CV Mosby Co.,St Louis, R 201.
Gregersen, E 1969, Acta Ophthalmol, 47: 579.
Krzystkowa, K and Pajakowa, J. 1972, Excerpta Medica Foundation, p. 72.
Dhir, RK 1967, J. All India Ophthal Soc, 1541-53.
Baum, W.W. 1942, Am. J. Ophthal 25: 291-295.
Pascal, J.' 1935, Arch. OphthaL 14: 624-626.
Burian, KM, Quoted by Von-Noorden, GK (1980), Binocular vision and ocular motility, The CV. Mosby, Co., St Louis, p. 288-290.
Scober, RG. and Green, EL 1948, Am J. Ophthalrnol, 31 :427-41.
Marton, RBB, 1941, Brit J. Physiol Opt 8: 100-102.
[Table 1], [Table 2]