He boldly applied surgery to curing patients though it was completely banned at that time.

While studying the Koryo therapy using medicine, acupuncture and moxibustion, he developed and applied a new method of curing external inflammation; cross-cutting pustule, letting pus out and cleaning it with salt solution.

Some of valuable therapies and experience left by him are recorded in the classics on Koryo medicine.

He cured every disease in combination of topical remedy and general treatment and detailed various operation methods, sterilizing methods and directions for medicine for external and internal application.

He also made and used scalpels of different shapes and specified the principles to be observed during operation.