No abstract

An isosorbide-induced decompression effect of the endolymphatic space was evident in spite of two different dosages of isosorbide (2.8 and 1.4 g/kg). Three hours after the isosorbide intake, however, the decompression effect was more marked in the group with the small dose (1.4 g/kg). Since significant rises in p-OSM and p-AVP were evident in the group with the large dose, this early rise of p-AVP due to dehydration seems to be the major reason for the delayed decompression effect in cases with a large isosorbide intake.

Postoperative vertigo is one of the common complaints after cochlear implantation (CI). Recently, development of new electrode designs and minimally invasive surgery have enabled preservation of residual hearing. At our department, an atraumatic electrode, FLEXSOFT of MED-EL, is inserted via the round window approach (RWA) and dexamethasone is administered intraoperatively and postoperatively to preserve vestibular function, regardless of the level of residual hearing ability. This retrospective study was aimed at determining the frequency of equilibrium dysfunction after minimally invasive CI.Between April 2018 and March 2019, 10 adult patients underwent minimally invasive CI surgery at our institution. The equilibrium function in these patients was assessed based on the symptom of vertigo, nystagmus, results of the caloric reflex test, measurement of vestibular evoked-myogenic potential (VEMP), and static stabilometry, before surgery and at various intervals after the surgery. One year after the surgery, 1/10 patients (10 ) reported dizziness, and nystagmus was observed in 2/10 patients (20 ). There were no abnormal results of the caloric reflex test after the surgery (0/4 side). Examination of the ocular VEMP (oVEMP) showed abnormal values before surgery on all sides. Examination of cervical VEMP (cVEMP) showed abnormal values after surgery on 5/9 sides (56 ). In the static stabilometer test, there was no significant deterioration in either the Romberg's ratio of velocity with foam rubber or the foam ratio of velocity with eyes closed after the surgery.Our study showed that the functions of the saccule can become impaired after minimally invasive CI. cVEMP may be most sensitive for detection of problems after CI surgery, since the saccule is anatomically closer to the implanted cochlea as compared to other vestibular organs.

Clear cell carcinoma (CCC) in the salivary gland is a rare malignant neoplasm and is hardly located in the nasopharynx. An 18-year-old female presented with a 3-year history of nasal congestion. Endoscopic examination revealed a reddish round-shaped mass with a smooth surface in the posterior wall of the nasopharynx. An en bloc resection of the tumor was performed by endoscopic surgery. Preliminary pathological diagnosis made by histopathological examination was mucoepidermoid carcinoma. However, FISH analysis for MAML2-split was negative but that for EWSR1-split was positive. In addition, EWSR1-ATF1 fusion transcript was detected in the RT-PCR analysis. The final pathological diagnosis of CCC was made on the basis of these findings. Since EWSR1-ATF1 fusion is not observed in other salivary gland tumors, identifications of this unique fusion gene by FISH and RT-PCR are useful tools to confirm the diagnosis of CCC.