50 TUBERCULIN DIAGNOSIS. 



culin in the sealed tube can be kept indefinitely. The pipette and graduate 

 are sterilized by dry heat, boiling or by thorough washing in boiling water. 



One drop of the tuberculin dilution is deposited into the inner angle of 

 the eye, and care should be taken that the drop is not immediately expelled, 

 but evenly distributed in the conjunctival sac. 



In tuberculous individuals the reaction appears in twelve to 

 Gradation of twenty-four hours, and according to its intensity can be 

 the Ophthal- divided into three grades, 

 mo Reaction. pi rs t Grade. Reddening of the caruncle and inner side of 



the lower lid (+) (see Fig. 2, Plate I). . 



Second Grade. Same as above but additional involvement of the con- 

 junctiva of the eyeball (-f +). 



Third Grade. Conjunctivitis purulenta, phlyctenulae and other such 

 severe manifestations ( + + +). 



The reactions of the first and second degree occur most frequently. The 

 manifestations associated with the former of these are so mild that the pa- 

 tient himself does not usually notice them. If the proper dilution is used and 

 the contraindications of this test are observed, a reaction of the third degree is 

 obtained only in exceptional cases. Fever never occurs. The other eye serves 

 as a control. It is advisable therefore before undertaking the reaction, to 

 note carefully any differences that may exist in the conjunctivas on both sides. 

 It must be remembered that i. The greater the dilution, the 

 Selection more specific is the reaction. 



of Correct 2. The test should not be repeated upon the same eye, even 

 Dilution, if there was no reaction at all at the first instillation. 



The following procedure should be adopted. A drop of the 

 2 per cent, tuberculin dilution is placed within the left eye. If a positive 

 reaction takes place, it is of great probability that the patient is suffering from 

 an active tuberculous process and thus the diagnosis is established. If, 

 however, that proves insufficient, and further corroboration is required, 

 the patient should receive after the first reaction has entirely subsided one 

 drop of a i per cent, tuberculin dilution into the right eye. 



If a negative reaction is obtained at the instillation of the 2 per cent, dilu- 

 tion, one drop of the 4 per cent, dilution is placed into the right eye. A 

 negative reaction with the 4 per cent, mixture speaks almost conclusively 

 for the absence of tuberculosis except in far advanced cachectic condi- 

 tions. A positive result does not, on the other hand, indicate the presence 

 of tuberculosis, as there are many normal individuals who react to a 4 per 

 cent, tuberculin concentration. 



The ophthalmo reaction is indicated in all suspicious cases of tuber- 

 Indications culosis where the presence of bacilli cannot be demonstrated 

 for Ophthal- anc [ wner e the subcutaneous reaction either on account of the 

 eactions. p resence o f temperature or other reasons cannot be undertaken. 



