Surgical approaches to congenital atresia of the external auditory canal

During the past 4 years, 22 patients with congenital atresia of the external auditory canal underwent 24 initial operations by either an anterior or transmastoid approach. No attempt at randomization was made, but the two groups were similar in number and pathology (in 14 cases approach was anterior and in 10 cases approach was transmastoid). Followup ranged from 6 months to 4 years. Hearing results were similar in the two groups (71% with air-bone gap less than 30 dB). There were no instances of facial nerve injury or sensorineural hearing loss. Facial nerve monitoring was used. Complications of stenosis and drainage were more common with the transmastoid approach. In both groups, hearing results were accomplished with the patients' intact ossicles or prosthetic reconstructions. Meticulous soft-tissue technique, with split-thickness grafts covering all exposed bone, is the key to preventing stenosis. For the three cases of patients with thick, acellular atresia plates, a different approach was developed. Maintaining proper orientation during the medial dissection is more difficult in these cases. By opening the antrum primarily and identifying the lateral canal, ossicles, and facial nerve, an ear canal can then be created anteriorly with these landmarks in view. An intact canal wall-like procedure is carried out. Although hearing results are similar, the anterior approach, because of fewer postoperative complications, is now our procedure of choice. Proper orientation and soft-tissue technique are the keys to successful correction of the congenitally atretic ear canal.     

Management of the external auditory canal in skull base surgery

Transtemporal approaches to the skull base are being used with increasing frequency. When the external auditory canal is transected in the course of these operations, the risk of cerebrospinal fluid fistula is created. When hearing is to be sacrificed, we use a modification of the technique developed by Rambo for closure of the external auditory canal. This technique permits a cosmetically acceptable reliable watertight closure. When hearing is to be salvaged, we use a "conchal flap technique," which prevents circumferential scarring and stenosis and permits a watertight suture closure.     

Basal cell carcinoma of the external auditory canal

Carcinomas of the external auditory canal are rare, nevertheless they are associated with a relatively poor prognosis. Among these tumours, basal cell carcinomas are less frequent than squamous cell carcinomas. Anyway, it is difficult to determine if their prognosis is better, as in other localizations on the body. We reviewed six patients, presenting locally advanced basal cell carcinomas of the external auditory canal and considered the history of their disease, the treatment procedures and final oncological outcome. Four of the patients died of the disease within five years from surgery. They presented local recurrences even after radical surgical excision in free tissue margins. From these findings we have the impression that basal cell carcinoma of the external auditory canal behave, even after radical surgery, as an aggressive tumour associated with a really poor prognosis.     

Pigmented nevus of the external auditory canal.

OBJECTIVE: To present the clinical experience during an 18-year period of a series of 11 cases of pigmented nevus of the external auditory canal (EAC). STUDY DESIGN AND SETTING: Retrospective medical review of 11 consecutive patients with lesions seen in 2 departments of otolaryngology in Taiwan. RESULTS: 12 pigmented nevi, 2 to 12 mm (average, 6.4 mm) in diameter, were excised under otomicroscopy, and the EAC was packed with a temporary Penrose stent. One large lesion developed a postobstructive external auditory canal cholesteatoma (EACC). Histopathologic examination revealed 11 intradermal nevi and 1 compound nevus. There have been no recurrences or stenoses of EACs after 3 months to 17 years (average, 6 years) of follow-up. CONCLUSION: If a pigmented nevus causes symptoms, especially when it is large enough to obstruct the lumen of the EAC and has the possibility of developing into an EACC, it should be excised. EBM rating: C-4.     

Malignancy of the temporal bone and external auditory canal

A retrospective study of 18 patients with malignant tumors of the external auditory canal and temporal bone was undertaken to gain an Asian perspective of this rare disease. Of these patients, 15 (83%) had squamous cell carcinoma (SCC) and 61% had stage T3 tumors at presentation. The mean age was 56 years (range 38-82 years). Seven (39%) of the 18 patients had radiation-associated tumors (RATs), and all had undergone radiotherapy for treatment of nasopharyngeal carcinoma. The 1-year cumulative recurrence for the RAT group was 100%, but there was no recurrence in the non-RAT group (P = 0.001). In malignancies of the external auditory canal and temporal bone, a different classification and staging system for patients with RATs may be warranted to better guide treatment strategies.     

Sterile preparation of the external auditory canal with povidone-iodine

Sterile preparation of the external auditory canal is usually not undertaken, although the external auditory canal provides surgical access for several procedures involving the tympanic membrane, middle ear, and vesibule. This is due to the rarity of postoperative wound infections, as well as difficulty in sterilizing the external auditory canal. Four antiseptic solutions commonly used for operative preparation were tested to determine thrir potential for sterilizing the external auditory canal. Povidone-iodine solution was effective in sterilizing 90% of the external auditory canals of children and adults. This simple technique may find clinical use in surgical procedures involving the external auditory canal.