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. Refraction and muscular imbalance, as simplified through the use of the ski-optometer. dia-gram, first, the existence of 6 degrees of ex-ophoria; second, 18 degrees of adduction;third, a weak left internus—the next proced-ure is to determine what degree of prism willenable the patient to obtain single binocularvision, with both eyes looking straight. To determine this, place both of the Ski-optometers rotary prisms in position with thehandle of each pointing outward red line or indicator of each prism shouldthen be placed at 30° of the outer scale(Fig. 26). The red Maddox ro
. Refraction and muscular imbalance, as simplified through the use of the ski-optometer. dia-gram, first, the existence of 6 degrees of ex-ophoria; second, 18 degrees of adduction;third, a weak left internus—the next proced-ure is to determine what degree of prism willenable the patient to obtain single binocularvision, with both eyes looking straight. To determine this, place both of the Ski-optometers rotary prisms in position with thehandle of each pointing outward red line or indicator of each prism shouldthen be placed at 30° of the outer scale(Fig. 26). The red Maddox rod should be horizontally[75] Refraction and Muscular Imbalance positioned before the eye, the white line onindicator pointing to 180° of the scale (). The strength of the rotary prism beforethe right eye should thereupon be reduced byrotating the prism indicator or red line towardthe upper zero (0) to a point where the pa-tient first sees the red streak—assuming thatthe red line appears at 42 degrees, that is 30degrees before the left eye and 12 degrees be-fore the A B Fig. 26 (A and B)—First position of rotary prisms to determine amount of prism exercise to be employed for building up the weak muscle. The prism should then be still further re-duced until the vertical streak produced bythe Maddox rod directly bisects the muscletesting spot of light. Assuming that this point [76] Refraction and Muscular Imbalance be thirty-eight degrees, which is four degreesless, single binocular vision is produced.
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Keywords: ., bookcentury1900, bookdecade1920, bookidrefractionmu, bookyear1921