Unilateral Mixed Hearing Loss Research Articles

Diagnosis and surgical reconstruction results for 14 cases of patients with congenital ossicular chain malformation

Objective:To investigate the diagnosis of common congenital ossicular chain malformation and the efficacy of ossicular chain reconstruction. Method:Fourteen cases with 15 ears of congenital ossicular chain malformation were included, consisting of 10 cases unilateral conductive hearing loss(10 ears), 1 case bilateral conductive hearing loss (2 ears) and 3 cases unilateral mixed hearing loss with significant conductive hearing loss(3 ears). Tympanoplasty was proceed on all 15 ears, 1 ear was proceed by loosen the cartilage fixation of ossicular chain and tympanic cavity wall. Fourteen ears were proceed with ossicular chain reconstruction, including 3 ears with TORP,10 ears with PORP and 1 ear with artificial stapes operation. The efficacy was measured by comparing the values of air bone gap(ABG) before and after the operation. Result:The average ABG of pre-operation was 39.9 dB, the ABG for 3 week and 6 to 8 months after operation were 22.3 dB and 19.6 dB, which were 17.6 dB and 20.3 dB improve respectively(t=22.10, P<0.01 and t=12.813，P<0.01). Conclusion:Operation is the first choice for those conductive hearing loss causing by simple congenital ossicular chain malformation, relevant ossicular chain reconstruction due to particular situation of the surgery can significantly improve hearing.

The Bone Conduction Implant—First Implantation, Surgical and Audiologic Aspects

To report on preoperative assessment, surgery, and audiologic outcome of the first patient implanted with the bone conduction implant (BCI). The BCI is a bone conduction hearing device with an intact skin solution where the transducer is implanted close to the ear canal opening. By avoiding a percutaneous screw attachment to the skull, the BCI is anticipated to reduce complications associated with the Bone-Anchored Hearing Aid (BAHA) solution. The first patient to receive a BCI was a 42-year-old woman with a unilateral mixed hearing loss due to tympanosclerosis. Preoperative and postoperative cone beam computed tomography and a virtual planning tool for 3D reconstruction were used to optimize and control the position of the BCI in the mastoid. The transducer was placed in a 5-mm deep seating in the mastoid and secured with a titanium bar. Free field tone and speech audiometry were conducted to evaluate the audiologic outcome at baseline (1 month postoperatively) and 1 month after baseline. The BCI was placed in the position according to the preoperative 3D planning. On average, the tone thresholds improved by 30 dB, speech reception thresholds by 25.5 dB and speech signal-to-noise ratio by 9.7 dB. The surgical procedure was considered simple and safe. The BCI can be implanted by a safe and easy surgical procedure. 3D preoperative planning can be helpful to optimize the BCI position. The BCI is a realistic alternative to the BAHA.

Incus Necrosis After Irradiation

Osteoradionecrosis (ORN) of the temporal bone is a rare, late complication of radiotherapy to the temporal bone region for head and neck or skull base tumours. ORN can occur as a localized or a diffuse type, according to the extension of the affected temporal bone. It can lead to otitis externa, otitis media, aseptic labyrinthitis and may lead to serious intracranial complications. Hearing loss may be conductive, sensorineural, or mixed. A few case studies report of previously irradiated patients presenting with conductive hearing loss presumably caused by ORN of the ossicular chain. In only one case report of diffuse ORN, ORN of the ossicles was histologically proven, leading to the conclusion that ossicular chain involvement as the sole entity of ORN would not exist. However, the presented case report disputes this. A 13-year-old boy presenting with a unilateral mixed hearing loss as the sole otological complaint, 10 years after radiotherapy for an anaplastic ependymoma. Middle ear inspection revealed ORN of the incus which was confirmed by histological investigation. ORN of the ossicular chain as a late complication can occur as an isolated entity and may present as conductive hearing loss predominantly in the low frequencies. Middle ear inspection and ossicular chain reconstruction should be attempted, bearing in mind the risk of iatrogenic lacerations of a thin tympanic membrane and possibly a delayed wound healing.

Bilateral semicircular canal aplasia

Bilateral semicircular canal aplasia is extremely rare; discovery, when the cochlear-vestibular system is normal and there is no hearing loss, is serendipitous. Bilateral semicircular canal aplasia was serendipitously discovered in a 24-year-old male during assessment of unilateral mixed hearing loss with subnormal contralateral hearing. The deformity was isolated, with no associated syndrome. Incidence of this isolated entity is unknown, but doubtless greatly underestimated due to the absence of associated symptomatology. To the best of our knowledge, this is only the second report of bilateral aplasia of the entire semicircular canal system involving unilateral hearing loss. A review of the literature focuses on the embryological and molecular aspects.

Phenotypic Variability of Osteogenesis Imperfecta Type V Caused by an IFITM 5 Mutation

In a large cohort of osteogenesis imperfecta type V (OI type V) patients (17 individuals from 12 families), we identified the same mutation in the 5′ untranslated region (5′UTR) of the interferon-induced transmembrane protein 5 (IFITM5) gene by whole exome and Sanger sequencing (IFITM5 c.–14C > T) and provide a detailed description of their phenotype. This mutation leads to the creation of a novel start codon adding five residues to IFITM5 and was recently reported in several other OI type V families. The variability of the phenotype was quite large even within families. Whereas some patients presented with the typical calcification of the forearm interosseous membrane, radial head dislocation and hyperplastic callus (HPC) formation following fractures, others had only some of the typical OI type V findings. Thirteen had calcification of interosseous membranes, 14 had radial head dislocations, 10 had HPC, 9 had long bone bowing, 11 could ambulate without assistance, and 1 had mild unilateral mixed hearing loss. The bone mineral density varied greatly, even within families. Our study thus highlights the phenotypic variability of OI type V caused by the IFITM5 mutation.

Sensorineural impairment in unilateral otosclerosis.

Audiometric findings were evaluated in a group of patients with clinical unilateral otosclerosis. A comparison was made between bone conduction threshold in the better hearing ear and the ear with the mixed hearing loss. Over 50% of the patients had a significant elevation in the bone conduction thresholds in the ear with clinical otosclerosis as compared to the uninvolved ear. A pair of temporal bones from a patient with unilateral otosclerosis and unilateral mixed hearing loss is presented.