No abstract

This chapter provides a brief history of online learning and a discussion of the empirical evidence for its acceptance and effectiveness.

Although the treatment o f the ordinarily incurable port wine birthmark by lasers has been practiced fo r more than 10 years, recent therapeutic investigations have been carried out particularly with the argon laser. Argon lasers now available fo r medical purposes produce treatment spots that are small. For certain practical reasons, at present, only relatively small portwine marks can be treated effectively. With trained personnel and proper safety measures, the treatment is safe fo r the patient and the operator. The treatment as yet is not proved to be better with the argon laser because the ruby laser and even an incoherent infrared thermal coagulator can produce similar and often larger cleared areas. It is recommended fo r the present that treatment o f portwine marks by argon lasers be restricted to investigation in medical centers where critical evaluations, control studies, and more powerful laser systems can be developed.