The most common surgery seen in otology clinics is surgery for otitis media, and of course surgery for middle ear cholesteatoma is also a surgery for otitis media. Patients often ask the question: Doctor, is it minimally invasive? The purpose of surgery is to remove the lesion and rebuild the function, so there is no doubt that there must be trauma. The concept of minimally invasive surgery is to minimize the trauma while fulfilling the purpose of the surgery. So minimally invasive surgery is a relative concept. Specifically in our otologic surgery, for simple chronic otitis media, often a CT will be done before surgery, and very often the CT room doctor will find some low density shadow in the mastoid air space and will report a diagnosis of mastoiditis. If the traditional surgical approach, which is still widely used, is used, the surgeon may grind off the bones of the mastoid process, in the name of removing the lesion. However, this CT diagnosis of mastoiditis is almost meaningless. The low-density shadow seen on these CTs is often just a “scar”-like tissue formed by the thickening of the mucosa after a previous episode of otitis media, which does not affect the outcome of our surgery. The air space inside the mastoid process is of great importance for the “breathing” of the ear. Then an otologist who has mastered the modern concept of minimally invasive surgery will avoid excessive surgery and will not need to make a large incision behind the ear, but only need to make a small incision at the eye of the ear to complete the surgery, which can be called “minimally invasive” surgery for simple otitis media. In the case of cholesteatoma, a long incision is made behind the ear because there is enough space to remove the cholesteatoma. Traditionally, the mastoid process is removed regardless of the size of the cholesteatoma, which is known as “mastoid contouring”. It has been clinically found that removing too much mastoid does not increase the effectiveness of the surgery, so otologists who have mastered the modern concept of minimally invasive surgery will remove only the cholesteatoma and the surrounding mastoid without making additional mastoid removal, and will repair the defect after the removal so that the post-operative ear canal is almost the same as the pre-operative one, without creating a large ear canal opening as in the traditional surgical approach. Then, although the incision looks the same as before, the inside is minimally invasive, which is the “minimally invasive” surgery for middle ear cholesteatoma.