Buku Ishihara 14 Plate [PDF]

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I’SHIi‹AnA's TESTS



COLOUO-BLINDNESS Concise



N.4N Fi IJAR 4 ‹i€, C O., LTD.



The Series oS Plates Designed as a



Test for Col our-Blindness SHINOBU IS HIHARA M.D., Dr. Med.sc.



Emeritus Professor of Opthalinology, Tokyo University, Member of the Japan Academy



Introduction This series of plates is designed to pro›’ide a test which gives a quick and accurate assessment of colour visiun deficiency of congenita] urigin. This is the commonest frcm of c‹›Iour •isicn disturbances.



ñ4ost cases of'cocgenital colour vision deficiency are characterized l›y a red-green deficiency which may he of two types: first. a protan type



hich may be complete ( protanopia} t›r partial (protanomalia T,



and, Secondly, a deutan type which may hu complete (deuteranupia j.



or partial Iduieranomalia). In prolanopia the s'isible range of the spectrum is shorter at the end compared with that of the normal, and thai part of the spectrum which appears to the normal as blue-green, appreurs to those with



protansipia as grey. The whole visible range of the spectrum in protanopia cansists of two areas which are separated from each other by this grey part. Each area appears to those with protanopia as one sys- tem of colour with different brightness and saturation within each area, the colour in one aren being different from that of the other. The red with u slight tinge of purp lc w hir h is the complementary rolour of blue-green appears also as grey. In dcuteranopia, that part of the spectrum wirh appears to the normal as green, appears as s**7. •fld the visible range of the spectrum is divided by this zone into two areas, each of which appears to be of one system of colour. The visible range of the spectrum is not contracted, in contrast to protanopia. Purple-red which is the comple- mentary colour of green appreas also as grey. In protanomia and deuteranomalia, there is no part of the spectrum which appears grey. But the part of spectrum which appears to those with protanopia as grey, appears to those with protanomalia as a greyish indistinct colour, and likewise, the grey part of the spec- trum seen by the person with deuteranopia appreas to those with deuteranomalia as an indistict colour close to grey. Consequently, one of the peculiarities of red-green deficiencies is that blue and yellow colours appear to be remarkably clear compared with red and green colours. The application of this peculiarity to the test for colour vision deficiencies is the distinguishing feature of this series. In the congenital colour vision deficiencies, although very rare, tbere is total colour weakness. The colour sensitivity of the total colour weakness to red and green. as well as to 3ellow and blue is ver3' low’ and only the clear colours can be perceived; but, except for the colour sensitivity, there is no abnormality in the visual functions. The plates in this book form an easy method of establishing the diagnosis on such cases and in distinguishing them from cases of red-green deficiensies. -2-



There is also a very rare group of persons who suffer from total colour blindness and show a complete failure to discriminate any col- our variations, usually witb an associated impairment of central vision with photophobia and nystagmus. Furthermore, a failure in the appreciation of blue and ywllow may be term tritanomalia if partial, and tritanopia if complete, but, esen if such cases do exist, they are extremely rare. The plates in this book are not designed for the diagonis of surh cases.



How to use the test



The plates are designed to be appreciated correctly in a room which is lit adequately by daylight. The-introduction of direct sunlight or the use of electric light may produce sronie discrepancy in the results because of an alteration in the appearance of shades of colour, When it is convenient only to use electric light, it should be adjusted as far as posible to resemble the effect of natural daylight. The plates are held 75 cm. from the subject and titled so that the plane of the paper is at right angles to the line of vision. The numerals which are seen on plates 8TO St8tetd, and each answer should be given without more than three seconds delay. It is not necessary in all cases to use the whole series of plates. Plates 12, 13 and l4 may be omitted if the test is designed merely to separate the colour detectives from those with normal colour appreei-



see the figures "96" but protanupia and strong prolanomalia



will read "6" unJy, and deuteranopia and strong deuterano-



Explanation of the platns



No. L



Any subject, whether with normul or defective colour vision will read correctly the figures "12". This plate is used mainly



malia "9" only.



to. 14.



trace along the purple and red lines. In protanopia and strung protanomalia nnly che purpie



for preliminary explanation of thr lest proress to the sub-



line ir traced and in case of mild prutanomaliB hnth line9



jects.



No.



a re t rac+d b u I the



?. Normal sub tecls will read "S" a nil ih‹›sc with red -green



No.



No.



Normal subjects will read "5" and those with red-green deficiencies "2". 4. Normal subjects will read "29" and those with red green deficiencies "70". 5. Normal subjects will read "74" and those with red-green deficiencies "21". hard to read for those with red -green deficiencies.



No.



line is Iraced and in case Df mild deuteramnalia both lines



3



No. 6-7. Correctly decipherable by normal subjects, but illegible or 8.



Clearly "2" for normal subjects but obscure for thuse with red -green deficiencies.



No. 9



Normal subjects can hardly read ir, but most of those with re d - g ree n d e ficie nc ie s see t he fig u re ” 2 " in i



No.



10. t. Normal subjects can usually read the figures "16", but most of those with red-green deficiences cannot.



No.



11. I n tracing the winding line between the two x's, the normal trace the bluish-green line, but the majority of those with colour vision deficiences are unable to follo'o' the line or fol-



pur p1e 1i ne is easi c r t‹› fcl lu w.



In deu rancpia anf strung deuteranomalia un]y the red



deficiensis "3".



No.



In tracing the winding lines bet ween the twc .s's, the normal



a re t r a c ed b ut I h e re d 1 i n e is ea s ie r Io f o1 I t› w'



Analysis of the results As assessment of t he re adin gs of plates 1 I o 11 determines the normality or defeciivenes of colour vision. If io or more plates are read normally, t he colour vision is regarded as normal. If only 7 or less tha n 7 plates are read no rmal, the colour s'is io n is regarded as deficient. flow ever, in reference to plate 9, onl y t hose who read t he numerals 2 a nd read it easier than ihose on piaie 8 are recorded as abnormal. It is rare to find a person whose recording of normal anwers is 9 or 8 plates. An assessment of such a case requires the use of other colour vision tests, including the anomaloscpe.



low a line different from the normal one. No.



No.



12. Normal subjects and those with mild red green deficiences see the figures "3fi" but protanopia and strong protanomalia will read "5" only, and deuteranopia and strong



deuteranomalia ” 3" only. 13. Normal subjects and those with mild red -green deficiences



-4-



Care of the Plate It is important that the bool h of tesl plates should be ke pt dosed, except during use, because undue exposure to sunlight causes a fading of the colour of the plates.



-5-



Answer to each plate



Number Normal of Plate Persaon 1



Person with RedGreen Deficiences



Person with Total Colour Blindness and Weskness



12



I2



12



x



2 5



2



4



29



70



x



5



74



21



X



x



7 45



X 2



X I II



X



1 ti



Protan



12



Strpng



btifd



fitronp



Mild



6



(96



9



9(6)



ss gg



14



Ueutao



I WO lilies



purple



purpie



The mark X sho*s thpt plalc cannnt be read. *l'he nuinwalñ andq inding i1nes in parenthesis show that they can be read or traced but tbey arc comparatiyelv unclear.



ISHIHARA'S TESTS



COLOUR -BLINDNESS By



Dr. SHINOBU ISHIHARA Profes sor Emrri'l us of fhr Uniur rail of To kgo Elem her of lh e Japan Acade my



Concise Edition



199 4



KANEHARA & TOKYO



CO., LTD.



JAPAN



Approved by



ISSHINKAI FOUNDATION



All Right Reserved



No part of this series of Plales nay he reproduced i n any form or



b y an y means wit h o ut i he w r i ite n permission of the Copy roghi owner



Published by



KANEHARA & CO., LTD. ‹ Medical Book Publ sher)



PO. Box No. I Hongn P.O. TOKYO I I3-0 I . JAPAN



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