![]() Early diagnosis of this condition is important as aggressive management is necessary to avoid morbidiy and mortality. Differential diagnosis includes cholestatoma and squamous cell carcinoma of the EAC. Temporal bone osteomyelitis is seen as increased density of the bone, with linear periosteal reaction, and accompanied by a soft tissue density around the EAC and mastoid. Involvement of the TM joint is seen as widening of the joint space, with irregularity of the articular margins. Involvement of the temporalis muscle leads to formation of a temporalis abscess, which is seen as diffuse muscle thickening with hypodensity. CT scan demonstrates the presence of an asymmetric soft tissue density in the EAC, with or without extension into the surrounding structures. The infection soon spreads into the adjacent structures such as the temporomandibular (TM) joint, middle ear, mastoid air cells, and skull base. It is commonly seen in the elderly and in diabetic patients. Malignant otitis externa is a result of infection of the EAC with Pseudomonas aeruginosa. Mortality has currently decreased to 20% from 30-40% due to good improved antibiotics. Malignant otitis externa is a misnomer as it is not a malignant condition it is termed “malignant” because of the aggressive clinical behavior and high mortality associated with it. 3D reconstructed images should demonstrate the volume of the middle ear cavity and also the distance from the middle ear structures to the atretic EAC and reveal any other anomalies of the external ear. Additional anomalies need to be looked for as well, such as the presence of severe incudomallear dysplasia, which when present has to be resected, as well as dysplastic stapes, which may need to be replaced by a prosthesis. In addition, we also need to look for structures that may cause problems during surgery such as reduced volume of the middle ear cavity and poor pneumatization of the temporal bone. Preoperatively, the radiologist should look for contraindications for surgery such as atretic oval and or round window and unfavorable course of the facial nerve. It is important to note that the outer and middle ear are. HRCT of the temporal bone is indicated for preoperative planning. 2 Patients have conductive hearing loss, with microtia or hypoplastic pinna a common association. ![]() It collects sound waves and channels them into the ear canal (external auditory meatus), where the. The outcome of surgeries performed in the presence of middle and inner ear dysplasia are not encouraging. A rare, otorhinolaryngological malformation characterized by failure in development of the external ear canal resulting in variable degree of malformations. The auricle (pinna) is the visible portion of the outer ear. ![]() Isolated EAC atresias are amendable to surgery. Atresia of the EAC can occur in isolation or it may be associated with middle ear and inner ear dysplasia.
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