Shinya Miuchi

Taste disturbance after stapes surgery--clinical and experimental study.

Conclusion: Most of the clinical cases experienced taste disturbance after stapes surgery, and in a few cases this disturbance persisted for a long time. The animal experiment suggested the role of geniculate ganglion (GG) cells in nerve generation. Objectives: To clinically examine taste disorder and its recovery after stapes surgery and experimentally demonstrate a role of GG. Patients and methods: Taste function after preservation of chorda tympani nerve (CTN) in stapes surgery was prospectively investigated with a questionnaire and electrogustometry (EGM). Further, expression of neurotrophic factors in GG after injury of CTN was examined by in situ hybridization histochemistry (ISSH) and RT-PCR. Results: Among the cases, 15/18 (83.3%) were associated with taste disturbance and 6/18 (33.3%) were associated with tongue numbness 2 weeks after surgery; however, the symptoms ceased in 14/18 cases (77.8%). Two weeks after surgery, the EGM threshold was found to be elevated in 15/18 cases (83.3%), while in 10/18 cases (55.6%), it did not decrease until 1 year after surgery. Expression of ISSH and amplified bands of BDNF and GFR increased at 7 and 14 days after nerve injury in ipsilateral GGs and also increased at 7 days on the contralateral side.

A case of pneumolabyrinth induced by Eustachian tube air inflation.

Objectives Here, we report a case of pneumolabyrinth induced by Eustachian tube air inflation (ETAI) with a catheter and present evidence that multiple air bubbles entered the perilymphatic space through a preexisting oval window fistula. Setting Tertiary referral center. Patient Sixty-six-year-old woman. Intervention(s) None. Main Outcome Measure(s) Air bubbles in the perilymphatic space revealed by cone beam computed tomography (CT) volume rendering imaging. Results The patient was referred to us because of vertigo, unsteadiness, and right hearing loss after ETAI using a Eustachian tube catheter. On Day 2, an audiogram showed right total deafness, and the perilymphatic space could not be identified on T2-weighted magnetic resonance imaging. A high-resolution cone beam CT scan obtained on Day 3 showed multiple air bubbles in the labyrinth. The volume rendering images clearly revealed a larger air bubble in the vestibule inside the footplate of the stapes and small air bubbles in the horizontal semicircular canal, superior semicircular canal, and basal and second turns of the cochlea. This finding indicates that the air bubbles entered the perilymphatic space through an oval widow fistula caused by a sudden elevation in intratympanic air pressure. Two months later, the air bubbles had disappeared, and the patient’s high tone hearing had improved slightly. Conclusion ETAI can cause a pneumolabyrinth if the intratympanic pressure rises beyond a certain critical level. In this situation, volume rendering imaging of high-resolution cone beam CT can be used to quantify and identify the air bubbles present. The images taken in this study suggest that air bubbles entered the perilymphatic space through a perilymphatic fistula.

Position of TORP on the stapes footplate assessed with cone beam computed tomography.

Objective To improve hearing outcomes of ossiculoplasty with a total ossicular replacement prosthesis (TORP) in ears lacking a footplate superstructure, 3-dimensional computed tomography (3D CT) images were reconstructed to verify the position of the TORP on the footplate and contact between the TORP and the stapes footplate. Study Design Retrospective study. Setting University-affiliated tertiary referral center. Patients Six ears of 6 patients who underwent ossiculoplasty with TORP and were followed for greater than 3 years postoperatively. Intervention Cone beam CT (CBCT) images. Main Outcome Measures An en face view of the stapes footplate and a volume-rendered 3D image were reconstructed. Results The en face view of the stapes footplate showed whether the TORP was centered on the stapes footplate. Volume-rendered 3D CBCT images revealed TORP malpositioning or migration, which were not detected on 2-dimensional CBCT images. In such cases, the TORP shaft was in contact with the wall of the oval window niche or the TORP had moved from the stapes footplate. Conclusion Accurate visualization of TORP location on the footplate is important. Images that accurately show the position of the TORP on the stapes footplate will help improve hearing outcomes.

Usefulness of the Saccharin Test for Assessment of Eustachian Tube Function in Patients With Chronic Otitis Media With Perforation.

OBJECTIVE The eustachian tube (ET) has two important functions, ventilation and clearance of the middle ear. We evaluated the ET ventilator function by the sonotubometry and the inflation-deflation test that are widely used today, and the ET clearance function by the saccharin test. Results of both tests were compared with surgical outcomes, and assessed which test was more closely related to the surgical outcomes. STUDY DESIGN Prospective case series. SETTING A single university hospital. PATIENTS AND INTERVENTION One hundred four ears of 95 patients with chronic otitis media with perforation underwent type I tympanoplasty. MAIN OUTCOMES AND MEASURES Based on sonotubometry and the inflation-deflation test, the patients were divided into normal, stenosis, and patulous types. Based on the saccharin test, they were divided into a normal function group and a partial/gross dysfunction group. Surgical outcomes about the hearing results and the condition of the eardrum were assessed 1 year postoperatively. Preoperative evaluation of ET function was compared with the surgical outcome. RESULTS Sonotubometry and inflation-deflation tests showed there was no significant difference among the groups about the hearing improvement and the surgical success rate. The saccharin test showed that the rate of the hearing improvement was significantly lower in the gross dysfunction group and that the success rate of Type I tympanoplasty was significantly higher in the normal group than in the dysfunction group. CONCLUSION There is a relationship between the saccharin test results and surgical outcomes.

The gray scale value of ear tissues undergoing volume-rendering high-resolution cone-beam computed tomography

OBJECTIVE When the thresholds for VR reconstruction from multi-slice CT images are changed, problems develop when assessing pathologies in the absence of standardized thresholds. The advantages of CBCT include lower radiation exposure compared with other techniques and better visualization of small ear structures. However, a disadvantage is that the scanner provides unstandardized gray scale values, thus not CT numbers (Hounsfield units, HU). METHODS We analyzed 88 sets of volume data obtained from temporal bones. The gray scale values were measured in aerated areas (two sites), along the ossicular chain (four sites) and in a bone area (one site) in the external and middle ears, and in soft tissue areas (five sites) and bone areas (two sites) in the inner ear. RESULTS The standard male and female gray scale values were 2448-2970 and 2585-3091 for the aerated areas, 3248-4945 and 3359-5223 for the ossicular chains, 3368-4109 and 3371-4147 for soft tissues, and 4790-5776 and 5044-5959 for bone, respectively. Sex significantly affected the values (p<0.05). Significant differences between aerated areas and ossicular chains, and between soft tissues and bone, were evident (all p<0.0001). CONCLUSION Volume-rendering (VR) images obtained by cone-beam computed tomography (CBCT) can be standardized simply by using fixed thresholds.

Endolymphatic Sac Assessed by 3D Cone Beam CT in Ménière Disease

Objective: The poster introduces new 3D Cone-beam CT (CBCT) images of endolymphatic sac (ELS). The volume rendering provides realistic image of ELS in relation to the semicircular canal, enabling one to assess location, size, and shape preoperatively. The results are compared with operative findings to confirm clinical values of the new imaging technology. Method: The 3D Cone-beam CT images of the 12 patients with Ménière diseases who underwent an endolymphatic mastoid shunt operation between 2008 and 2011 were obtained at our hospital. We assessed location, size, and shape of the ELS. The results of preoperative assessments were compared with the operational findings. Results: First we present clear and sharp 3D pictures of ELS and the semicircular canal using volume rendering incomparable to conventional CT. In 11 patients, the ELS was located exactly along the Donaldson line. In one patient, it was located inferiorly to the line. Size of the ELS was moderate in 6 patients, small in 5, and exceedingly small in 1. Cross section of the sac was circular in 3 patients, oval and flat in 8, and unverified in 1 because the size was too small. The above findings agree with the operational findings closely. Conclusion: In 3D Cone-beam CT, we could get more informative and better quality images than in conventional CT. Thanks to the preoperative realistic 3D images of ELS and the semicircular canal, we could perform the sac operation more safely and easily. Imaging information thus obtained may help deepen the understanding of Ménière’s disease.

S128 – Diagnosis and Treatment of 703 Patients with Taste Disorder

Objectives As life spans increase, the number of patients with taste disorder consulting in our taste clinic has increased. This study prospectively examined patients’ history, causes of taste disorder, and treatment outcomes. Methods Subjects consisted of 703 patients with taste disorder who consulted our taste clinic at the department of Otolaryngology, Hospital of Hyogo College of Medicine, between 1999 and 2007. There were 284 men and 419 women, and patient ages ranged from 12 years to 88 years with a mean age of 59.7 years. Electrogustometry (EGM) and filter paper disk method (FPD) were used to assess taste function. We also asked each patient to indicate the severity of symptoms using a visual analog scale (VAS). Patients were treated mainly with zinc sulfate (ZnSO4 300 mg/day, or polaprezinc 150 mg/day), and in some cases with iron supplement, herbal medicine, and minor tranquilizers. Results Idiopathic taste disorder was the most common cause (271 cases, 38.5%), followed by drug-induced (131 cases, 18.6%), post-common cold (83 cases, 11.8%), psychogenic (73 cases, 10.4%), iron-deficiency (37 cases, 5.3%) and others. Deficiency of serum zinc (less than 70 ?g/dl) was found in 50–70% of cases. The recovery rate was 130/183 (71.0%) in idiopathic, 41/61 (67.2%) in post-common cold, and 24/29 (82.8%) in iron deficiency. The recovery period in drug-induced (39.7 weeks) was longer than that in other cases (20.4 weeks). Results of EGM and FPD were not always associated with the severity of symptoms. Conclusions Treatment with zinc supplement may be useful for taste disorder.

P086: Taste Disturbance and Its Recovery after Stapes Surgery

hearing loss. Both were evaluated through lumbar puncture with cerebrospinal fluid cytology and MRI of posterior fossa. RESULTS: Two patients presented with rapidly progressive, bilateral sensorineural hearing loss. One patient also had a complete unilateral facial paralysis. MRI of the brain demonstrated enhancing lesions in each internal auditory canal. Lumbar puncture with cerebrospinal fluid (CSF) cytology was performed for both patients. CSF cytology was positive for malignant cells in the patient with facial paralysis with subsequent diagnosis made of adenocarcinoma of the colon. The patient died within two weeks of diagnosis. The other patient had a history of ductal cell carcinoma of the breast, which was believed to be metastatic to the internal auditory canals. There have been less than 30 cases reported of bilateral sensorineural hearing loss due to meningeal carcinomatosis. The majority of these 30 cases were due to adenocarcinoma. CONCLUSIONS: The differential diagnosis of patients with progressive, bilateral sensorineural hearing loss should include metastatic disease. Facial paralysis in this situation is a poor prognostic sign. CSF cytologic analysis may help to determine if lesions found on MRI are due to malignant disease.