Disorders of the External Ear

3.8.1 Discuss the embryology of the external ear. At what time during embryogenesis does the auricle develop?

3.8.2 Name the normal landmarks of the auricle? What are the normal dimensions of the auricle?

3.8.3 Discuss the etiology, management and potential complications of auricular hematoma.

3.8.4 From an embryologic standpoint, explain a first branchial cleft anomaly (type I and II) and why the facial nerve needs to be considered in surgical excision of this anomaly.

3.8.5 What is microtia? What are the different classifications and the overall incidence?

3.8.6 Discuss the appropriate evaluation for the patient with unilateral microtia?

3.8.7 What additional considerations need to be made in the case of bilateral microtia with complete aural atresia? What is the incidence of bilateral occurrence?

3.8.8 Discuss the course of the facial nerve in cases of aural atresia.

3.8.9 What is the ideal age for reconstruction of aural atresia? What are the important considerations for timing?

3.8.10 Discuss the Jahrsdorfer and De La Cruz classifications systems for grading aural atresia. Are there any absolute indications and contraindications for atresiaplasty?

3.8.11 Discuss the rehabilitation options for unilateral microtia. Discuss the different surgical stages and their timing.

3.8.12 What are the stated success rates for surgical repair? What are the most common complications?

3.8.13 Review the anatomy of the external auditory canal. Describe the “ideal” external canal environment.

3.8.14 Differentiate exostoses vs. osteomas.

3.8.15 Acute otitis externa…bacteriology and treatment.

3.8.16 Why does fungal otitis externa occur? How can you tell it is fungus? What is the treatment?

3.8.17 Discuss the various ways to manage cerumen impaction. Which do you prefer and why. How will you instruct patients on proper aural hygiene?

3.8.18 Discuss the staging of squamous cell cancer of the external ear.

Moody SA, Hirsch BE, Myers EN. Squamous cell carcinoma of the external auditory canal: an evaluation of a staging system. Am J Otol. 2000 Jul;21(4):582-8. PMID:10912706

3.8.19 What is chronic stenosing external otitis?

Birman CS, Fagan PA. Medial canal stenosis--chronic stenosing external otitis. Am J Otol. 1996 Jan;17(1):2-6. PMID:8694128

3.8.20 An elderly patient presents to the ER with severe otalgia and auricular edema. The ER doc calls you for a consultation. He does not suspect malignant otitis externa because the patient is non-diabetic. Educate him… Shpitzer T, Stern Y, Cohen O, Levy R, Segal K, Feinmesser R. Malignant external otitis in nondiabetic patients. Ann Otol Rhinol Laryngol. 1993 Nov;102(11):870-2. PMID:8239349

3.8.21 Discuss the typical history and physical exam of a patient with malignant otitis externa. What is the most common cranial nerve affected? Name medical conditions other than diabetes that are potential risk factors for this condition.

3.8.22 When is the role of nuclear medicine studies, MRI, and CT in the diagnosis and management of malignant otitis externa? Are there any laboratory studies that can be used to follow a patient with malignant otitis externa?

3.8.23 What is the current recommended management for patients with malignant otitis externa ? (Please comment on length of treatment, single or double coverage, role for surgery if any, topical therapy, hyperbaric oxygen). Aside from pseudomonas, what are some other potential pathogens that can cause this condition?

3.8.24 Describe the two conditions that are depicted in these illustrations. How does the pathophysiology of these conditions differ? How would you manage these conditions?