Anotia Infant Ear is characterized by the absence of the entire outer part of the ear. This ear deformity is the most severe grade IV microtia ear deformity and is relatively rare (one to two infants in 10,000 births). It most commonly occurs in one ear, but it also occurs bilaterally. Most anotia patients have middle and inner ear structures but often suffer from conductive hearing loss. In this condition, sound waves have difficulty penetrating the ear and being heard. This is usually a condition that can be improved during the course of anotia treatment.