Blind Sac Approach Using Silastic Block for Cochlear Implantation in Patients with Cholesteatoma

Cochlear implant (CI) surgery in cholesteatoma is challenging because of the risk of residual or recurrent infection. Although CI could be done with subtotal petrosectomy in single or staged surgery, this surgery needed additional surgical procedures to obliterate the mastoid cavity. This paper describes a new surgical technique for CI surgery in cholesteatoma without external auditory canal closure.

Blind Sac Approach Using Silastic Block for Cochlear Implantation in Patients with Cholesteatoma

Cochlear implant (CI) surgery in cholesteatoma is challenging because of the risk of residual or recurrent infection. Although CI could be done with subtotal petrosectomy in single or staged surgery, this surgery needed additional surgical procedures to obliterate the mastoid cavity. This paper describes a new surgical technique for CI surgery in cholesteatoma without external auditory canal closure.

Expression Changes of Endothelin-1, Endothelin Receptor A and B in the Cochlea after Noise Exposure / 대한이비인후과학회지

BACKGROUND AND OBJECTIVES: There are several evidences of reduced cochlea blood flow after noise exposure in the cochlea. However, the pathophysiology of blood flow change is still obscure, and endothelins, proteins that constrict blood vessels and play a key role in vascular homeostasis using its receptors may have importance in this respect. In this study, we investigated the expression changes of endothelin-1 (ET-1), endothelin receptor A (ETAR) and B (ETBR) according to auditory threshold change after noise exposure. MATERIALS AND METHOD: Mice were exposed to different noise to generate transient (group 2) and permanent threshold shift (group 3), respectively. Auditory threshold shifts were evaluated with auditory brainstem response and expression changes of ET-1, ETAR and ETBR after noise exposure were evaluated by immunohistochemistry and real time RT-PCR. RESULTS: After noise exposure, the increased ET-1, ETAR and ETBR immunoreactivities were observe in stria vascularis, spiral ligament and spiral ganglion neuron. ET-1 mRNA expressions increased after noise exposure in both group 2 and group 3 compared to those of the control group. At 2 weeks after noise exposure, however, the ET-1 mRNA expressions in group 3 increased compared to that of the control but decreased compared to that of group 2. On the other hand, ETAR mRNA expression increased at 2 weeks after noise exposure in both groups, just after noise exposure in group 2 and at 2 weeks after noise exposure in group 3. CONCLUSION: These results suggest that expression changes of ET-1, ETAR and ETBR might be associated with hearing threshold shift and recovery after noise exposure in the cochlea.