Bilateral congenital absence of stapes and oval window in 2 members of a family: etiology and management

Abstract

To date, bilateral congenital absence of stapes and oval window in 2 members (brother and sister) of a family has not been reported in the literature. Carhart's notch as one of the indications for the diagnosis of this disease is proposed. The etiology and management of this condition are discussed. The older brother and younger sister of a family had severe bilateral hearing loss and concomitant speech disability since early childhood. Their parents are first cousins and have 2 sons and 1 daughter, but the younger son is in good health with normal hearing. No similar disease was found among other relatives. Physical examination showed that the older brother and the younger sister had normal external ears and tympanic membranes. Congenital bilateral absence of stapes and oval window were confirmed by history, audiologic examination, high-resolution computed tomography scanning, and/or surgery. The modified Lempert's fenestration operation on the horizontal semicircular canal was performed on 1 ear of each patient. Postoperative hearing threshold was 25 dB for speech frequencies with a gain of 47 dB for the older brother and 28 dB for speech frequencies with a gain of 52 dB for the younger sister. Follow up at 5 to 13 years individually, their hearing gains were steady. Both sister and brother now enjoy a normal life. Bilateral congenital absence of stapes and oval window in the 2 family members may be related to inheritance. This report points out Carhart's notch as noted in otosclerosis as an important indication for diagnosis of this disease. The modified Lempert's fenestration operation of the horizontal semicircular canal is a safe and good choice for these patients and a better choice than a hearing aid throughout life.