LIGHT THERAPY MAYER 409 



cases, of which the foregoing is typical, 1 am convinced that this 

 recovery is directly related to the light therapy and occnrs fre- 

 quently if the disease is not of the acute progressive type and if 

 the patient's condition is not too poor. However, these are only 

 clinical impressions, and experimental proof is yet needed. 



Other forms of tuberculosis which in my experience are frequently 

 helped by mercury arc light exposures (when light is used only as an 

 aid) are the " hilus glandular," or so-called hidden tuberculosis of 

 children and adults, and the superficial forms of tuberculosis, such as 

 the cutaneous, oral or pharyngeal, laryngeal (except the acute and 

 the edematous forms), corneal and phlyctenular ocular tuberculosis, 

 and the lymph node and peritoneal tuberculosis. Less favorable in 

 their response but yet often improved are genito-urinary, and bone 

 and joint tuberculosis. Postoperative sinuses after nephrectomy are 

 especially responsive. 



Reliance on any source of light as an important aid in pulmonary 

 tuberculosis is not to be encouraged. 



From the foregoing presentation of the present status of light 

 therapy it is evident that harm may be done by the injudicious and 

 uninformed use of light. Valuable as this method has proved itself 

 to be in a limited number of diseases, it is surely clear that much 

 more investigation and many more scientific data are required before 

 light should be generally prescribed by those unfamiliar with the 

 contraindications and the details of its application. 



