This past year (2017) there was a statistical data made that stated foreigners that came to receive medical treatment spent approximately 270 Million US Dollars. Meaning that this made a whopping 30 percent of South Korea's medical market. These numbers blew me away but it seems like its from a credible source (Yeonhap News). The total amount of foreigners stated were approximately 425,380 people.
Amoungst the 425,380 people:
20% were from physician treatment
11.3% were from plastic surgery
11.1% Dermatology visits
9.3% Examination check-ups (xray,catscan, bloodwork, ect)
3.2% General Surgery
I was expecting Plastic Surgery to be far higher than the rest but I guess South Korea is pretty well known for all aspects of Medical Industry.