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ARTICLES |
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Year : 1982 | Volume
: 30
| Issue : 4 | Page : 371-373 |
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Evaluation of acquired colour defects by F.M. 100 hue test
RG Sharma, YC Mishra, GL Verma, U Goswami
Deptt. of Ophthalmology, S.M.S. Medical College, Jaipur, India
Correspondence Address: R G Sharma Department of Ophthalmology, S.M.S. Medical College & Hospital, Jaipur India
Source of Support: None, Conflict of Interest: None | Check |
PMID: 6984695
How to cite this article: Sharma R G, Mishra Y C, Verma G L, Goswami U. Evaluation of acquired colour defects by F.M. 100 hue test. Indian J Ophthalmol 1982;30:371-3 |
A battery of tests have been designed to furnish information about various congenital colour defects but most of the tests are complex and often give conflicting results. Further some tests are specially task oriented and some are used for screening purposes to differentiate normal from abnormals. Yet the tests to differentiate congenital colour defects are very much lacking.
In the present study our endeavour has been to assess the officacy and clinical usefulness of F.M. 100 Hue test in detection of colour defects frequently encountered in various ocular and systemic diseases.
Materials and methods | | |
31 cases of various fundus lesions were subjected for evaluation of colour defects on F.M. 100 Hue test and Ishihara test 15 normal individuals were also subjected for F.M. 100 Hue so as to obtain normal scoring pattern. Cases of following fundus lesions were subjected for colour value evaluation :
Group A- Macular lesions: 5 cases, 3 heredo macular degeneration and 2 non specific macular degeneration).
Group B- Tapeto-retinal degeneration5 cases
Group C-Amblyopia ex anopsia-5 cases Group D-Optic nerve lesions-6 cases, 3 primary optic atrophy, 2 post neuritic optic atrophy I Retrobulbar neuritis.
Group E-Chorio retinitis-5 cases
Group F-Diabetic Retinopathy-5 cases
None of the eyes tested had visual acuity less than 6/60. The state of colour vision in each eye was recorded with the help of pseudo isochromatic plates of Ishihara and subsequently F.M. 100 Hue test was applied. These colour vision examination were done in natural day light with normal pupil.
F.M. 100 HUE TEST | | |
It is a Hue discrimination test comprising of 5 wooden cases with a total of 93 plastic caps on which different coloures are mounted. Each wooden cases consists of 2 hinged panels with enclosed 21 or 22 numbered colour caps which are removable. 2 caps are repeated and fixed as pilot caps at each end of the panel. The object of this test is to arrange the caps in a regular colour series between the two fixed pilot caps. The scoring sheet of F.M. 100 Hue test consist of 4 rows of numbers and circular diagram for scoring. The order of caps is recorded in the rows of numbers and errors of transposition identified. The score of a cap is the sum of differences between the number of that cap and the number of caps adjacent to it. The inner circle of numbers 1 to 85 represents 85 colour chips which make up a full colour circle and every single chip is separated from each of its neighbours by a just noticabie difference in the Hue. Thus the test measures the Zones of colour defective individuals.
ADMINISTRATION OF F.M. 100 HUE TEST | | |
The person to be tested was made well conversant with the test. Each wooden case was opened before the examinee who was then instructed to arrange the coloured caps in a regular colour series between the two pilot caps within 2 minutes (Approx.). The score of each cap was then marked accordingly on the radial lines of the scoring sheets and points were connected to each other to obtain the graphic recording of the error scores so as to know the colour spectrum effected. The F.M. 100 Hue pattern thus obtained indicate the colour zones of best and poorest perception and the degree of colour discrimination in these zones.
Observations | | |
15 normal individuals between the age groups of 25 to 47 years had an error score ranging from 12 to 72 on F.M. 100 Hue test (within the normal prescribed limit of error score up to 100).
Group A-Macular lesions; (5 cases)
Testing on pseudo isochromatic plates of Ishihara showed total colour blindness (achromaptopsia) in 2 out of 5 cases and remaining cases showed no abnormality.
On F.M. 100 Hue test all the cases had high error scores than normal. 3 out of 5 cases had error score ranging from 300 to 394. Only 2 cases had their error scores of 126 and 253. 7 out of 10 eyes had blue green and yollow defect. The remaining 3 eyes had generalised loss of Hue discrimination.
Group B-Tapete retinal degeneration
On pseudo isochrometic plates of Ishihara, 4 cases showed no abnormality and only one case showed achromatopsia. On F. M. 100 Hue test majority of patients had error score lying between 200 to 400. Patients with macular involvement had relatively higher error scores. Majority of cases showed tritan defect. Maximum errors were committed in blue green and yellow green ranges. A case of fundus albi punctus had tetarten defect.
Amblyopia exanopsia | | |
All the patients could read all the pseudo isochromatic plates of Ishihara correctly with each eye separately. On F.M. 100 Hue test, 4 cases out of 5 had their amblyopic eye error score lying between 100 to 200. Five cases had the error of 219. 4 patients had tritan and tetratan axis and only one case had poor discrimination of all the Hues.
Optic nerve lesions | | |
On pseudo isochromatic plates of Ishihara, only one case with retrobulbar neuritis could not read any of the plates while rest of the 5 cases did not show any abnormality. On F.M. 100 Hue test cases of primary optic atrophy had tetarten and deutan defects while cases of post neuritic optic atrophy had protan axis of defect. A case of retrobulbar neuritis had generalised less of Hue discrimination with remarkably high error score (555). Rest of other cases had error scores lying between 100 to 200. Maximum error were concentrated in red purple and blue green range of spectrum.
Choreoretinitis | | |
On pseudo isochromatic plates of Ishihara non of the cases showed any abnormality.
On F.M. 100 Hue test the error scores ranged between 100 to 300. Maximum errors were committed in red-purple, blue and bluegreen range of spectrum.
Discussion | | |
Grutzner[1] suggested that the anomalesope method and most of the pseudo isochromatic plates are inadequate for detection of tritanomalies as observed in various retinal diseases. Pseudo isochrometic plates of Ishihara are of little value for assessment of acquired colour defects both quantitatively and qualitatively. Only 4 cases out of 31 showed an abnormality and that too of achromatopsia. The profile of F.M. 100 Hue test is characteristic for a particular disease pattern and a precise information regarding the colour spectrum involved can be obtained.
Fishman[2] reported defect of red receptor in inflammatory lesions of macular whereas the degenerative lesions produced blue-green defects. However, in our patients protan axis was also found in one eye of a case of heredomacular degeneration. Francois and Varriest[3] reported tritanopic defects in cases of tapeto retinal degeneration. Our results in this series showed tritan as well as deutan and tatartan axis of defects.
Although colour sense of an amblyopic eye is generally normal as suggested by Francois and Varriest but dyschromatopsia for blue has been reported. Even achromatopsia with amblyopia has been reported by Auerbach and Kriplee[4]. In our patients 4 out of 5 cases had their errors concentrated mainly around tritan axis. None of the patients had achromatopsia.
In patients with postneuritic optic atrophy errors were concentrated around red-purple and blue-green range of spectrum. In contrast to the patients of primary optic atrophy who had tritan and tetratan defects. Similar observations have been described earlier by Kelecom 5. Thus F.M. 100 Hue Test helps to differentiate post neuritic type of optic atrophy from primary optic atrophy where there is a tritan defect.
The results obtained from this study support the fact that degenerative lesions of macula give rise to blue-green defect as compaired to inflammatory lesions which show redgreen defect. Pigmentary lesions of choroid and retina give rise to blue-green and yellowgreen defect with a tendency to shift towards red-purple range in cases where macula is also effected. In general patients with amblyopia exanopsia had only minor colour vision abnormality for blue ranged spectrum. Lesions involving conducting pathways i.e. lesions of optic nerve head lead to deterioration of redgreen discrimination. Metabolic diseases like diabetic retinopathy produce blue-green and yellow-green defect. Acquired blue-yellow deficiencies are encountered in degeneration of photo receptors of the peripheral retina (Tapeto-retinal degeneration).
F.M. 100 Hue test, though time consuming, it provides both qualitative and quantitative information indicating by how much and in what manner the patient's colour vision departs from normal.[5]
References | | |
1. | Crutzner, 1961, Albrecht, V. Fraefes Arch. Ophthalmol 163, 99. |
2. | Fishman G., 1971, Sur. Ophthalmol. 15: 370 |
3. | Francosis, J and Varriest, G., 1961, Vis. Res.1:201. |
4. | Auerbach, E. and Rriplee, B., 1974, Decum. Ophthalmol 37: 119. |
5. | Kelecom, J., 1963: Arch. Ophthalmol. (Paris) 23:15. |
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