Subjective Reading Test
Tilt Ski-optometer forward in making reading test. The wide groove in the horizontal bar supporting the instrument, permits it to be slightly tilted.
12th—Place Ski-optometer reading rod in position with card at about 14 inches. Close off one eye. Direct patient’s attention to the name “Benjamin” printed at top of card.
13th—Leave cylinder lens in place. Proceed as in distance test with +6.D sphere, fogging down until the first word “laugh” on the reading card, in line 75M, is perfectly clear, this being slightly smaller than the average newspaper type.
14th—After completion of examination for each eye separately, then with both eyes direct patient’s attention to word “laugh.” Move reading card in or out a few inches either side of 14 inch mark. This will determine any possibility of an over-correction. Then record prescription just as Ski-optometer indicates. For a detailed description of above, as well as for objective testing with the Ski-optometer, read [chapter three].
Chapter VI
MUSCULAR IMBALANCE
The purpose of the present chapter is to acquaint the refractionist with the operation of the Ski-optometer as “a scientific instrument for muscle testing”—the subject being treated as briefly and comprehensively as is practicable.
As the reader progresses in the subject of muscular anomalies, he may carry his work to as high a plane as desired, increasing his professional usefulness to an enviable degree.
Through the use of the Ski-optometer, muscle testing may be accurately accomplished in less time than a description of the operation requires. Furthermore, tedious examinations may be wholly overcome through the discontinuance of the consecutive transference of the various degrees of prisms from the trial-case. In fact, the latter method has long been quite obsolete, owing to the possibility of inaccuracy. The muscle action of the eye is usually quicker than the result sought through the use of trial-case prisms; hence muscle testing with the Ski-optometer is accomplished with far greater rapidity and accuracy, thus making the instrument an invaluable appliance in every examination.