Endoscope-Assisted Cochlear Implantation

OBJECTIVES: Our aim was to present our endoscope-assisted cochlear implantation (CI) technique, in which the middle ear landmarks were identified through the facial recess exposure by using an endoscopic view without elevating the tympanic annulus. The secondary goal was to assess whether the situation of difficult surgical exposure could be predicted by evaluating preoperative axial computed tomography (CT) examinations. METHODS: CT examinations and surgical outcomes of endoscope-assisted CI surgeries were analyzed. RESULTS: A total of 179 CI operations performed in 27 adults (15.1%) and 152 children (84.9%) were retrospectively evaluated. It was found that in 14 cases (7.8%), endoscopic examination contributed substantially in identifying the round window (RW) membrane correctly. Endoscopic identification of the RW through the posterior tympanotomy enabled us to perform a straightforward surgery in all these cases, without the need for switching to a bony cochleostomy or alternative surgical techniques. The difficulty in the surgical exposure was predicted preoperatively by examining the axial CT scans in six of the 14 cases (42.8%) for which endoscopic assistance was necessary in order to identify the RW correctly. CONCLUSION: The main benefit of endoscope-assisted CI is the improved visibility leading to a panoramic view of the RW region. The implementation of transfacial recess endoscopic examination into the conventional CI technique is helpful to avoid problems during surgical orientation. However, the difficulty in the surgical exposure of the RW cannot be reliably predicted by the subjective evaluation of preoperative CT scans and more studies are needed to obtain reliable criteria.

Effects of Topical Intranasal Doxycycline Treatment in the Rat Allergic Rhinitis Model

OBJECTIVES: Allergic rhinitis (AR) is a chronic upper respiratory tract disease that inflames the mucous membranes of the nose and occurs when circulating inflammatory cells including eosinophils and basophils migrate to and accumulate in the inflammation area by passing through the interstitium and capillary walls. To pass through these barriers, the inflammatory cells degrade extracellular matrix proteins. Matrix metalloproteinases (MMPs) released by inflammatory cells mediate the degradation of these proteins. MMPs have synthetic inhibitors and doxycycline, a tetracycline antibiotic, inhibits MMPs. This study investigated the efficiency of intranasal doxycycline in decreasing the symptoms and inflammatory cell infiltration in an animal model of AR. METHODS: AR was created in female Wistar rats by repeated intranasal challenge with ovalbumin by intraperitoneal injection. For 15 days, topical intranasal doxycycline was administered one hour before ovalbumin administration. Following intranasal administration, nasal symptoms were scored and the nasal mucosae of all rats were evaluated histopathologically. To investigate tissue changes, hematoxyline-eosin and Alcian blue/periodic acid Schiff stains were used. As well, cilia loss, goblet cell changes, vascular congestion, vascular proliferation, inflammatory cell infiltration, eosinophil infiltration and the degree of hypertrophy in chondrocytes were evaluated with light microscopy. RESULTS: Typical symptoms of AR were decreased by intranasal doxycycline administration. These effects were stable after repeated intranasal ovalbumin administration. Histological evaluation of doxycycline treated rats did not reveal typical inflammatory changes associated with AR. CONCLUSION: MMPs may have crucial functions in AR and topical intranasal doxycycline, which decreases inflammatory cell infiltration, may offer an alternative therapy for AR.