Year : 1969 | Volume
: 17 | Issue : 6 | Page : 242--244
Abnormal retinal correspondence, evaluation of the diagnostic procedures
MK Garg, IS Jain, SD Gupta
Department of Ophthalmology, Postgraduate Institute of Medical Education & Research, Chandigarh, India
M K Garg
Department of Ophthalmology, Postgraduate Institute of Medical Education & Research, Chandigarh
|How to cite this article:|
Garg M K, Jain I S, Gupta S D. Abnormal retinal correspondence, evaluation of the diagnostic procedures.Indian J Ophthalmol 1969;17:242-244
|How to cite this URL:|
Garg M K, Jain I S, Gupta S D. Abnormal retinal correspondence, evaluation of the diagnostic procedures. Indian J Ophthalmol [serial online] 1969 [cited 2021 Nov 27 ];17:242-244
Available from: https://www.ijo.in/text.asp?1969/17/6/242/38547
Abnormal retinal correspondence (A.R.C.) is a condition where the two fovea, which are normally corresponding points, lose their common visual directions and acquire different ones---an extramacular element of one eye adopts the visual direction of the fovea of the other eye. Although much work has been done on the diagnosis of this condition, there is a lot of controversy on the importance of the various diagnostic procedures. Smith  stated that the best method for the determination of false projection is the use of amblyoscope. Burian  also agreed with her but he suggested the use of more than one test for diagnosis of ARC. Bagolini and Capobianco  on the other hand had shown that the presence of A.R.C. can be easily detected and thus more frequently diagnosed by the use of Bagolini's striated glasses than with the major amblyoscope or by the after-image test. According to Flom and Kerr  diagnostic disagreement between tests for retinal correspondence can be explained by measurement error, unsteady eccentric fixation and relative change in the position of eyes.
The present study has been conducted to resolve the above controversy.
Material and Methods
All the cases who were co-operative and intelligent, and showed A.R.C. on any of the three following tests were included in the series comprising of 80 patients.
i) Synoptophore test-The objective and subjective angles were found on the synoptophore. Patients having unequal angles were labelled as cases of A.R.C. Where the angle of anomaly (difference between objective and subjective angle) is equal to the objective angle, A.R.C. is of harmonious type and if the angle of anomaly is less it is unharmonious. Cases where subjective angle could not be accurately recorded because of suppression, but the objects at the objective angle were not superimposed were also labelled as having A.R.C.
ii) After image test-This test was done on Synoptophore (Clement Clarke Model 2052). First, the right eye was exposed to a vertical slit with a red central fixation point for 10 seconds, and then the left eye was similarly exposed to a horizontal slit for 10 seconds. The automatic flashing unit was then switched on. In N.R.C. the patient sees an after image in the form of a cross (+) and with A.R.C. the patient sees lines crossing each other away from the centre.
iii) Bagolini's striated glasses test Bagolini's striated glasses, which leave the transparency of the glass and the visual acuity of the patient unaltered are used. A normal subject wearing a pair of striated glasses at right angles, sees a light crossed by two luminous stripes, each ray being perceived only by one eye. If the stripes do not bisect at the light but cut each other to one side it shows the patient has A.R.C. A cross (+) through the light source in the presence of squint indicates harmonious A.R.C.
These three tests were performed on every patient and the presence or absence of A.R.C. and the type of A.R.C. where possible, were noted.
These eighty cases included 50 patients of concomitant squint and 30 of straight amblyopia. The following observations were made.
Striated glasses test was positive for A.R.C. in 94% and was of the harmonious type in 84% of the cases. On major amblyoscope corresponding figures were 84% and 40%. With after image test, only the harmonious type of A.R.C. could be diagnosed with certainty and the test was positive in only 62% of cases.
All the patients in this group had eccentric fixation. Seeing a cross (+) on after image test in the presence of eccentric fixation indicated a harmonious type of A.R.C. Bagolini's test also showed harmonious type of A.R.C. in all these cases. Cover test did not show any squint. Even on major amblyoscope no deviation of the eye and A.R.C. could he demonstrated. All the cases had binocular vision.
The above study comprising of 80 cases of A.R.C. was designed to know the utility of different diagnostic procedures. The after image test is positive for A.R.C. in only 62% of cases and the unharmonious type cannot be diagnosed with certainty. In many patients the test cannot be performed because of suppression of the squinting eye. Major amblyoscope test is positive in a greater number (84%) of cases but the harmonious type is detected less often. Suppression of the squinting eye was again a hinderance in the test in many cases. Striated glasses test gives positive results in maximum number (94%) of cases and 84% of these are of harmonious type.
Looking at these figures one would imagine that just the striated glasses test is enough for the diagnosis of A.R.C. This probably is true for the cases of harmonious A.R.C. but the unharmonious type of A.R.C. cannot be diagnosed with certainty unless the angle of squint and the shift of the line from the centre can be measured accurately for the same distance. Maximum positive results for A.R.C. with Bagolini's striated glasses is probably due to the test being performed under natural test conditions. (Bagolini et al  ).
In a given case, we therefore feel that any one test is not enough. To get full information about the retinal correspondence more than one test repeated on 2-3 occasions would be more helpful.
All our cases of straight amblyopia with A.R.C. fall into the group of microtropia-described by Helveston and von-Noorden  . Only the after image test and the Bagolini striated glasses are helpful in the diagnosis of A.R.C. in these cases.
Our observations are in agreement with those of Pasino and Maraini  and Bagolini et al  . We do not agree with Smith  that the best method for determination of A.R.C. is the use of the major amblyoscope, nor do we agree with Flom et al  that the diagnostic disagreement can be explained by measurement error, unsteady eccentric fixation and relative change in the position of eyes. Striated glasses test has the added advantage of being simple, non time consuming and of being done under natural and non-dissociating test conditions of the eye without impairing visual acuity of the patients.
Eighty cases of A.R.C. are examined by the amblyoscope test, the after image test and striated glasses test.
Striated glasses test gives the maximum number of positive results for A.R.C. but no on esingle test is complete.
Importance of multiple tests in a given case is stressed.
|1||Bagolini, B. and Capobianco, N. M.: Subjective space in comitant squint, Amer. J. Ophthal. 59, 430-442 (1965).|
|2||Burian, H. M.: Sensorial retinal relationship in concomitant strabismus. Arch. of Ophthal. (Chicgao) 37, 336368, 504-533, 618-648, (1947).|
|3||Flom, M.C. and Kerr, K. E.: Determination of retinal correspondence. Arch. of Ophthal. (Chicago), 77, 200213 (1967).|
|4||Helveston, E. M. and von-Noorden. G. K.: Microtropia (A newly defined entity). Arch. Ophthal. (Chicago). 78. 272-281 (1967).|
|5||Pasino. J. and Maraini. G.: Importance of natural test conditions in assessing sensory state of squinting subject. Brit. J. Ophth.. 48. 30-34. (1964).|
|6||Smith, M. I.: Significance of false projection in the treatment of squint. Arch. Ophthal. (Chicago). 21, 990-998 (1939).|