Stapedectomy in children

Stapedectomy in children has aroused much controversy regardless of its specific motivation, whether a fixed stapes is operated on because of a developmental anomaly, otosclerosis, or injury. J.W. House and co-workers (3) began their 1980 report on this subject with the words: „Stapedectomy on a child? Never! But we believe there are indications”, whereas B. Teunissen and co-workers (4, 5) are of the opinion that children who qualify for stapedectomy can be operated upon on certain conditions: 1. They must be over 10 years of age at the time of operation. 2. They must be free for any length of time from episodes of otitis media secretoria. 3. The procedure must be preceded by tone and speech audiometry, and by contralateral stapedial reflex examination. 4. In children with hypoacusis of the mixed type, a CT scan of the temporal bones should be performed. According to H.P. House (1, 2), unilateral hypoacusis caused by congenital stapes fixation does not require operative treatment, but bilateral hypoacusis must be corrected surgically by the time the child attends school.

In the period from 1993 to 1998 24 children (32 ears) aged 5-16 years, with congenital malformations of the auditory ossicles were operated in the Department of Otolaryngology. The medical history of all the patients met the criteria of congenital hypoacusis proposed by House (2). The children presented with the following features: 1. distinct conduction hypoacusis from infancy, 2. unprogressive hypoacusis with a stable hearing level, 3. a typical audiogram with an air conduction curve of -50 to 60 dB with an accompanying bone conduction curve of 0-10 dB. None of the children was afflicted with chronic inflammatory conditions of the ears nor suffered from head injury in the past. Among 32 operated ears with developmental anomalies of the auditory ossicles, in 21 ears the malformations related to the stapes and the oval window. In 12 ears an isolated form of stapes fixation was reveałed at operation without distinct malformations of the malleus and the incus. In 4 ears an immobile stapes was more or less deformed (a monocrural stapes, a stapes with thick crura devoid of an opening, a stapes with delicate elongated crura), in 3 ears stapes and oval windows were missing, and in 2 cases there was an immobile stapes with missing incudostapedial joint (Table 1). In 15 patients (11 girls and 4 boys, 21 ears) various types of stapedectomias were performed. In 10 ears the surgical „small window” technique was employed, in 5 ears a prothesis suspended after stapedectomy on a long crus of the incus was grounded on the fatty tissue closing the oval window, and in 1 case transposition of a deformed incus was performed. In the remaining 5 ears TORP prostheses were used and grounded on the fatty tissue closing the newly formed window into the vestibule. In patients with stapes malformations, the first and second branchial arch syndrome was identified twice, proximal symphalangism once, frontometaphyseal dysplasia once, Klippel-Feil syndrome once, and incomplete Mohr´s syndrome once. In all the patients, prior to their qualification for the surgical procedure, a CT scan of the temporal bones was performed in order to exlude developmental anomalies of the inner ear. Assessment of hearing before and after operation was based on tone audiometry by determination of the arithmetical mean, median and standard deviation of the air and bone conduction thresholds for four frequencies: 500, 1000, 2000, 4000 Hz. The results obtained were elaborated statistically using the T-Student or Wilkcoxon´s tests.