[Mutant prevention concentrations of garenoxacin against Streptococcus pneumoniae isolates from otorhinolaryngological infections].

The minimum inhibitory concentrations (MICs) and the mutant prevention concentrations (MPCs) of garenoxacin (GRNX), were compared to those of levofloxacin (LVFX), and moxifloxacin (MFLX) against 78 Streptococcus pneumoniae isolates from otorhinolaryngological infections in Japan during the period January 2007 to June 2007. The MIC and MPC for 90% of the isolates (MIC90 and MPC90) of GRNX were 0.06 and 0.12 microg/mL, respectively, and were the lower values than LVFX and MFLX MIC90s and MPC90s. The ratios of MPC/MIC of GRNX were the lower values than those of LVFX and MFLX.

Cochlin-tomoprotein: a novel perilymph-specific protein and a potential marker for the diagnosis of perilymphatic fistula.

BACKGROUND: Perilymphatic fistula (PLF) is an abnormal connection between the inner and middle ear. A procedure for obtaining definite proof of a PLF remains elusive, and methods of diagnosis remain controversial. To date, there is no clinically relevant biochemical marker for perilymph leakage. Using proteomic analysis of inner ear proteins, we have previously found unique properties of cochlin, encoded by the COCH gene. We detected 3 cochlin isoforms (p63s, p44s and p40s) in the inner ear tissue and a short 16-kDa isoform of cochlin-tomoprotein (CTP) in the perilymph. Since cochlin was found to be highly specific to the inner ear, we speculated that CTP might also be specific to the perilymph. The aim of this study was to determine whether CTP, a novel perilymph-specific protein, could be used as a marker for the diagnosis of PLF. METHODS: By Western blotting, we investigated the specificity of CTP expression in a range of body fluids that included perilymph, serum, saliva and cerebrospinal fluid. To elucidate the detection limit of CTP, serially diluted recombinant human (rh)CTP as well as human perilymph was tested. RESULTS: CTP was selectively expressed in all 20 perilymph samples tested, but not in 77 samples of the other body fluids. The detection limit of rhCTP was 0.27 ng or 0.022 microl of perilymph per well on Western blot analysis. CONCLUSION: The results strongly suggest that CTP can be a specific marker of perilymph leakage. Moreover, CTP has the potential to be a biochemical marker that allows a definitive diagnosis of the etiology of PLF-related hearing loss and vestibular disorders.

[Tissue and aural discharge distribution of tebipenem pivoxil].

Tebipenem pivoxil (TBPM-PI) is a novel oral carbapenem antibiotic. It has been developed as a prodrug of tebipenem (TBPM), to increase absorption. We assessed the distribution of TBPM to aural discharge and tissues after administration of TBPM-PI to adult patients who underwent otolaryngological surgical tissue resection and pediatric patients with acute otitis media or acute sinusitis. Following the administration of single oral doses of 150 and 250 mg (potency) of TBPM-PI to adult patients who underwent otolaryngological surgical tissue resection, tissue TBPM concentrations for the respective doses were 0.38 to 1.76 microg/g and 0.17 to 0.91 microg/g in mucous membranes of the maxillary sinus, 0.26 to 0.94 microg/g and 0.14 to 0.45 microg/g in mucous membranes of the ethmoid sinus, and 0.12 to 0.13 microg/g and 0.14 to 0.47 microg/g in palatine tonsil tissues, as well as 0.29 microg/g in mucous membranes of the middle ear for the dose of 250 mg. The percentages of these tissue concentrations to plasma concentrations for the respective doses were 14.3% to 61.0% and 18.4% to 54.6% in mucous membranes of the maxillary sinus, 34.3% to 52.1% and 9.9% to 54.6% in mucous membranes of the ethmoid sinus, and 10.3% to 15.0% and 6.5% to 17.4% in palatine tonsil tissues, as well as 16.8% in mucous membranes of the middle ear for the dose of 250 mg. Following the administration of TBPM-PI at doses of 4 mg (potency)/kg and 6 mg (potency)/kg twice daily to pediatric patients with acute otitis media or acute sinusitis, TBPM concentrations in the aural discharge for these doses were 0.03 to 2.00 microg/g and 1.07 or 1.18 microg/g, respectively. The percentage of aural discharge concentrations to plasma concentrations for these doses was 0.3% to 86.1% and 40.5% or 83.6%, respectively. These results indicate a favorable distribution profile of TBPM to tissues affected by otitis media or sinusitis after the administration of TBPM-PI and can support the high efficacy of TBPM-PI.

[Clinical efficacy, safety and PK-PD analysis of tebipenem pivoxil in a phase II clinical trial in otolaryngological infections].

UNLABELLED: We conducted a double-blind intergroup comparative study investigating the efficacy, safety and PK-PD analysis of the new oral carbapenem antibacterial drug tebipenem pivoxil (TBPM-PI) for the treatment of otolaryngological infections in adults to establish the recommended clinical dosage. The primary endpoint was the clinical effect of a 7-day oral administration of TBPM-PI to subjects with confirmed cases of infection by any of the 5 major bacterial species causative for otolaryngological infections (Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus pyogenes, Moraxella catarrhalis, and Haemophilus influenzae) assigned to three groups set according to the TBPM-PI dosage, namely, a 450 mg group (150 mg t.i.d), a 500 mg group (250 mg b.i.d), and a 900 mg group (300 mg t.i.d). 1. Clinical efficacy: At the end of administration or at discontinuation, the efficacy rate for the 112 subjects in the efficacy analysis set was 72.1% (31/43 subjects) in the 450 mg group, 88.6% (31/35 subjects) in the 500 mg group, and 85.3% (29/34 subjects) in the 900 mg group. Both the 500 mg and 900 mg groups showed a high efficacy rate of over 80%. 2. Bacteriological efficacy: The disappearance rate of the pre-administration causative bacteria (5 major bacterial species) at the end of administration (at discontinuation), it was 92.2% (47/51 strains) in the 450 mg group, 94.7% (36/38 strains) in the 500 mg group, and 91.7% (33/36 strains) in the 900 mg group. All the groups showed a high disappearance rate, with no large differences among them. All strains of S. pneumoniae, including PRSP, as well as those of S. pyogenes and M. catarrhalis disappeared. The overall disappearance rate of H. influenzae was 78.6%, namely, 76.9% in the 450 mg group, 100% in the 500 mg group, and 66.7% in the 900 mg group, showing differences among the groups. 3. PK-PD: The PK-PD analysis was executed in 124 strains isolated from 111 subjects in which the plasma TBPM concentration and the MIC of causative organism were measured. The target value of the PK-PD parameter was examined from the relation between PK-PD parameter and bacteriological efficacy. The presumed target value of AUCf/MIC was 10-20, Cmaxf/MIC was 4. On the other hand, a clear relation was not found between T>MIC and the bacteriological efficacy. 4. SAFETY: The incidence of adverse reactions related to symptoms and signs was 28.8% (21/73 subjects) in the 450 mg group, 35.8% (24/67 subjects) in the 500mg group, and 30.6% (22/72 subjects) in the 900 mg group. The incidence of abnormal changes in laboratory test values was 8.2% (6/73 subjects) in the 450 mg group, 9.2% (6/65 subjects) in the 500 mg group, and 9.9% (7/71 subjects) in the 900 mg group. There were no differences in either of these categories among the groups, and the incidence was considered not to be correlated with dose. Based on the above, we considered that TBPM-PI at doses of 250 mg b.i.d (500 mg/day) promises high clinical usefulness for the treatment of otolaryngological infections in adults.

[Antimicrobial susceptibility surveillance of recent isolates from otorhinolaryngological infections to garenoxacin and other antimicrobial drugs].

The antimicrobial susceptibility of 339 isolates from the otorhinolaryngological infections at the otorhinolaryngological departments at 27 universities in Japan, as well as their 108 affiliated hospitals and practitioners during January 2007 to June 2007 was determined to garenoxacin (GRNX), levofloxacin, moxifloxacin, azithromycin, cefditoren, and cefcapene applicable for otorhinolaryngological infections. The in vitro activities of these drugs against the isolates were compared. The quinolones including GRNX were potently active against Streptococcus pneumoniae including penicillin-intermediate and -resistant strains (PISP and PRSP), Streptococcus pyogenes and methicillin-susceptible Staphylococcus aureus, except for MRSA, a major causative pathogens for otorhinolaryngological infection. When MIC ranges, MIC50, MIC80 and MIC90 of three quinolones were compared, it was considered that GRNX was the most active of them. GRNX was potently active against Haemophilus influenzae and Moraxella catarrhalis same as that of other quinolones tested. In conclusion, GRNX exhibits a potently active against fresh isolates from otorhinolaryngological infections, and has an effective potential in the treatment of otorhinolaryngological infections.

A case of a mucocele in an Onodi cell.

Onodi cells have been defined as posterior ethmoid cells that have pneumatized laterally and superiorly to the sphenoid sinus. They are often close to the optic nerve or the internal carotid artery. A patient complained of a sudden decrease in left eye visual acuity and left eye pain due to formation of a primary mucocele in an Onodi cell. A coronal computed tomography scan and magnetic resonance imaging were useful for diagnosing the mucocele.

[Epidemiological survey of pneumococcus serotypes in pediatric patients with acute suppurative otitis media].

To determine the distribution of Streptococcus pneumoniae serotypes isolated from patients under 6 years of age with acute suppurative otitis media, to calculate the serotype coverage of 7-valent pneumococcal conjugate vaccine, and to clarify trends in PCG-resistant Streptococcus pneumoniae, we conducted a one-year prospective study from April 2005 to March 2006 at 10 medical institutions in Hokkaido, Miyagi, Chiba, Tokyo, Kanagawa, and Mie, Japan. Specimens collected by tympanotomy or myringotomy numbered 856, and 691 strains were isolated from 599 specimens. Of these, 219 isolates (31.7%) were identified as Streptococcus pneumoniae and 201 met study requirements. The most common serotype was 19F (52 isolates, 25.9%), followed by 6B (30 isolates, 14.9%) and 23F (24 isolates, 11.9%). Seven-valent vaccine serotype coverage was 62.7%. The percentage of PSSP was 40.3%, PISP 42.8%, and PRSP 16.9%, resistant strains (PISP and PRSP) combined accounted for 59.7%. Seven-valent vaccine serotype coverage for PISP was 80.2% and PRSP 82.4%. PBP gene mutation was observed in 175 isolates (87.1%), including 70 of gPISP (34.8%) and 105 of gPRSP (52.2%). Gene mutation induced by macrolides was found in 176 isolates (87.6%).

A case of meningeal carcinomatosis presenting with the primary symptoms of facial palsy and sensorineural deafness.

We report the case of a 59-year-old man with meningeal carcinomatosis (MC) who presented with peripheral facial palsy and progressive sensorineural deafness. The patient had been operated on for gastric cancer 1 year previously, and no metastases had been detected in the retroperitoneum or thorax at follow-up examination 1 year later. However, he developed headache, deafness, and peripheral facial palsy and was referred to us for further evaluation, as magnetic resonance of the head had shown no abnormalities. Ramsay Hunt syndrome was suspected, but no increase in the cerebrospinal fluid cell count was detected. On the other hand, the balance test suggested a central disorder. In addition, the plasma level of carcinoembryonic antigen suddenly increased, suggesting MC. The cerebrospinal fluid was examined several times; in the end malignant cells and an increase in the cell count were detected, and the diagnosis of MC was established.

A case of ectopic parathyroid gland hyperplasia in the pyriform sinus.

Variability in the location of parathyroid glands is well recognized. There are usually 4 parathyroid glands located in the area of the thyroid gland, but embryologically, they may be found anywhere from the angle of the jaw to the pericardium. We report a case of an ectopic parathyroid gland in the pyriform sinus. It appeared as a tumorous lesion in the pyriform sinus owing to progress of secondary hyperparathyroidism.

Topical ofloxacin for chronic suppurative otitis media and acute exacerbation of chronic otitis media: optimum duration of treatment.

OBJECTIVE: To assess the optimum duration of topical ofloxacin therapy for chronic otitis media and to compare the response between patients with chronic suppurative otitis media (CSOM) and acute exacerbation of chronic otitis media (AE). STUDY DESIGN: Prospective observational study. SETTING: Five university hospitals and 30 affiliated institutions. PATIENTS: A total of 294 patients who presented to the participating institutions with CSOM were enrolled. Among them, 268 patients were evaluable for safety and 237 were evaluable for efficacy (64 with CSOM and 173 with AE . INTERVENTION: Ofloxacin otic solution was administered for as long as 4 weeks. MAIN OUTCOME MEASURES: Clinical and bacteriologic assessment was done weekly during the treatment period. The clinical response was assessed on the basis of the symptom scores. RESULTS: There were no differences between CSOM and AE patients with respect to sex, age, and severity. The most common bacterial isolate from middle ear discharge was Staphylococcus aureus. The clinical response rates in patients with CSOM and AE were 39.1% and 61.3% after 2 weeks of treatment and 57.8% and 75.1% after 4 weeks, respectively, and the bacterial eradication rate was 91.0% at 2 weeks and 94.6% at 4 weeks. Detection of new fungal infection did not increase as the duration of therapy was prolonged. No serious adverse events were reported. CONCLUSIONS: The duration of treatment was shorter and the clinical response was higher in AE patients than in CSOM patients. The standard topical ofloxacin regimen for chronic otitis media should consist of a 2-week course from the aspect of bacteriologic efficacy, although patients showing insufficient symptomatic improvement after 2 weeks may benefit from another 1 or 2 weeks of therapy. Administration of this drug for as long as 4 weeks can increase the clinical efficacy without causing safety problems.

Postoperative olfaction in chronic sinusitis: smokers versus nonsmokers.

In order to study the efficacy of surgical intervention, as well as the influence of cigarette smoking on olfaction in clinical states, we examined olfactory ability by means of the University of Pennsylvania Smell Identification Test (UPSIT). We enrolled 37 patients 21 to 60 years of age who underwent surgery for chronic sinusitis. Normosmia was defined as an UPSIT score of 30 or more. Among these patients, 31 had a disturbance in their smelling ability in the preoperative stage, and the improvement rate, defined as a rise in score of 4 or more points after surgery, was 64.5%; 11 were well healed. However, all 7 patients who were more than 40 years old at the time of surgery, and currently smoking cigarettes, had a significant deficit in olfaction in the preoperative stage and even in the postoperative stage. This study demonstrated that cigarette smoking has adverse effects on olfactory ability, especially for older patients.

IL-5 and eotaxin levels in middle ear effusion and blood from asthmatics with otitis media with effusion.

OBJECTIVE: The purpose of this study was to evaluate eosinophil infiltration as well as IL-5 and eotaxin levels in middle ear effusion (MEE) and blood from otitis media with effusion (OME) patients with asthma and to compare the findings with those from OME patients without asthma (control group). MATERIAL AND METHODS: Levels of IL-5 and eotaxin in MEE and blood were measured by means of enzyme-linked immunosorbent assay. RESULTS: 5 levels in MEE were significantly higher than those in blood in both groups of patients and in OME patients with asthma than in the control group. In addition, in OME patients with asthma, there was a significant correlation between the percentage of eosinophils and IL-5 levels in MEE. Eotaxin levels in blood were significantly higher than those in MEE in both groups of patients and in OME patients with asthma than in the control group. In addition, in OME patients with asthma, the percentage of eosinophils and eotaxin levels in blood tended to correlate, but did not reach statistical significance. CONCLUSION: These data suggest that, in OME patients with asthma, eosinophilia in MEE depends more on IL-5 than on eotaxin, and that eotaxin may play an important role in the mobilization of eosinophils from the bone marrow into the blood.

Subjective evaluation of post-tympanoplasty hearing in relation to the pure tone threshold.

OBJECTIVE: In the year 2000, the Otological Society of Japan proposed a new criteria to assess the levels of hearing known as Criteria 2000. However, these criteria are intended to assess pure tone threshold after tympanoplasty and the results do not necessarily reflect the hearing condition from the patient's perspective. Thus, it is essential to study the relationship between the subjective evaluation of post-operative hearing based on the patient's own assessment and the objective assessment by audiometry. METHODS: The present study is a questionnaire-based survey on the levels of post-operative hearing in 460 patients whose degree of satisfaction with their levels of hearing was assessed by visual analogue scale (VAS). The hearing level was assessed based on the Criteria 2000 established by the Otological Society of Japan. RESULTS: The post-operative results indicated a success rate of 78.7%. According to the questionnaire-based survey, 64.4% patients considered their hearing as "improved". The average VAS score was the highest in the "improved" group and gradually decreased when in the "deteriorated" group. The highest success rate was obtained in patients who assessed their hearing as "improved" and the lowest rate was seen in those who assessed their hearing as "deteriorated". On the other hand, the success rate in the three groups, "slightly improved", "unchanged", and "slightly deteriorated", was almost similar and did not relate to the objective audiometry findings. Therefore, except for the "improved" and deteriorated" groups, there is no relation between the subjective self-assessment and the objective post-operative hearing. CONCLUSION: A bi-directional approach, one from an audiological (objective) and one from the patient's perspective (subjective), especially using VAS, is quite useful for the post-operative assessment of hearing.

Expression of caspase-activated deoxyribonuclease (CAD) and caspase 3 (CPP32) in the cochlea of cisplatin (CDDP)-treated guinea pigs.

Cisplatin, an anti-cancer drug, is known to induce apoptosis. During apoptosis, double-stranded DNA is broken into single-stranded DNA by the action of caspases and caspase activated deoxyribonuclease (CAD). We immunohistochemically examined the cochlea of guinea pigs for signs of the apoptosis after the administration of cisplatin. Cisplatin (10 mg/kg b.w.) was intraperitoneally injected to guinea pigs and 3 days later, the animals were sacrificed by intracardiac perfusion of 4% paraformaldehyde. The temporal bones were then removed and immunohistochemically stained for CAD and caspase 3, using the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end-labelling method. CAD was observed in the stria vascularis and the spiral ligament. Caspase 3 was also detected in the stria vascularis, the spiral ligament and the supporting cells of the organ of Corti. These findings suggest that apoptosis is involved in the cochlear damage observed in cancer patients treated with cisplatin.

Subjective evaluation and overall satisfaction after tympanoplasty for chronic simple suppurative otitis media.

A questionnaire survey was conducted in 324 patients with chronic, simple, suppurative otitis media who had undergone tympanoplasty 6 months or more previously to investigate post-operative hearing, tinnitus, vertigo, occlusive feeling of the ear and otorrhea. In addition, the overall satisfaction with tympanoplasty was assessed by VAS value. Subjective hearing improvement was observed in 73.1% of the patients whose hearing was poor and in 50% of those whose hearing was good before the operation. The degree of satisfaction assessed by VAS value corresponded with the subjective hearing assessment. As to tinnitus, 66.2% of the patients became aware of the disappearance or alleviation of symptoms. In the case of patients who had tinnitus before the operation, the degree of awareness of tinnitus and the degree of satisfaction assessed by VAS value coincided. However, no changes in the VAS value were observed in those who did not have tinnitus before the operation. As for vertigo, 30.5% of the patients who had vertigo preoperatively became aware of the disappearance of the symptoms after the operation. The degree of satisfaction assessed by VAS value corresponded with the presence or absence, severity and frequency of vertigo. As to the fullness of the ear, alleviation of the symptoms was subjectively noted by 85.9% of the patients who had symptoms before the operation. The degree of satisfaction assessed by VAS value corresponded with the severity of the symptoms in those who had symptoms before the operation. As for otorrhea, the disappearance of the symptoms was subjectively noted by 85.5% of the patients who had otorrhea before the operation. The degree of satisfaction assessed by VAS value corresponded with the post-operative changes in otorrhea. Based on the above results, it was assumed that the patients placed greatest expectation on hearing improvement when they underwent tympanoplasty. VAS is considered a useful method to evaluate the degree of satisfaction of patients after surgery.

Significance of preserving the posterior branch of the great auricular nerve in parotidectomy.

OBJECTIVE: Sensory disturbance due to excision of the great auricular nerve in patients who have undergone parotidectomy sometimes causes discomfort to the patients. In order to reduce the postoperative discomfort of the pinna, we tried to preserve the posterior branch of the great auricular nerve. METHODS: Forty patients with parotid tumor were included in this study. Twenty-one of these patients had pleomorphic adenoma, 16 had adenolymphoma and 3 had a low grade malignant tumor. Sensations of the pinna and the quality of life (QOL) after parotidectomy were evaluated using a 0-100 Visual Analogue Scale (VAS) assessed at 2 weeks, 1 month, 2 months, 3 months and 6 months after parotidectomy. RESULTS: The posterior branch of the great auricular nerve was preserved in 26 out of 40 patients (65%). No difference was observed in the incidence of complications except sensory disturbance of the pinna with this surgical procedure as compared to the surgical technique where the great auricular nerve was excised. The VAS score for the sensation was significantly higher in the group of patients whose great auricular nerve was preserved at 2 months (35.0+/-20.8 vs. 18.5+/-9.2), 3 months (64.4+/-18.3 vs. 26.4+/-13.8) and 6 months (66.9+/-16.2 vs. 26.6+/-11.4) after parotidectomy. The VAS score for the QOL was also significantly higher in the group of patients whose great auricular nerve was preserved at 2 months (50.3+/-21.8 vs. 35.1+/-14.5), 3 months (69.5+/-27.5 vs. 45.9+/-22.6) as well as 6 months (71.9+/-24.1 vs. 45.7+/-19.1) after parotidectomy. CONCLUSION: Preservation of the posterior branch of the great auricular nerve during parotidectomy is valuable in order to reduce the postoperative sensory disturbance of the pinna that follows conventional surgery. It further helps to improve the QOL of these patients after parotidectomy.

A comparative study on the observation of spontaneous nystagmus with Frenzel glasses and an infrared CCD camera.

OBJECTIVES: To compare the usefulness of a CCD camera with infrared illumination (IR-CCD camera) over Frenzel glasses (F Glasses) for the observation of spontaneous nystagmus, the incidence and direction of nystagmus, and the frequency, amplitude and slow phase of spontaneous nystagmus. METHODS: One hundred vertiginous patients, fifty-three females and forty-seven males participated in this study. Before undergoing routine neurotological examination, their eye movements were recorded by electronystagmogram (ENG) in conjunction with observations of eye movements under F glasses and through an IR-CCD camera. The data was collected from patients who exhibited spontaneous nystagmus either under F glasses or the IR-CCD camera. RESULTS: Thirty-three patients showed spontaneous nystagmus under F glasses. On the other hand, under the IR-CCD camera, all patients examined exhibited spontaneous nystagmus. The frequency of nystagmus was not significantly different between these two systems. However, the amplitude and slow phase velocity exhibited significantly larger values under the IR-CCD camera in patients with spontaneous nystagmus both under the IR-CCD camera and F glasses. CONCLUSION: From these observations and evidence, the IR-CCD camera can be recommended as a more useful system and powerful tool for neurotological examination than F glasses.

WITHDRAWN: Mutant prevention concentrations of garenoxacin against Streptococcus pneumoniae isolates from otorhinolaryngological infections.

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Cochlin-tomoprotein (CTP) detection test identifies traumatic perilymphatic fistula due to penetrating middle ear injury.

CONCLUSIONS: The cochlin-tomoprotein (CTP) detection test can be used to make a definite, objective diagnosis of traumatic perilymphatic fistula (PLF), and therefore offers valuable information on patient selection for surgical treatment. OBJECTIVES: Penetrating middle ear injury can cause traumatic PLF, which is a surgically treatable otologic emergency. Recently, we have reported on CTP, a novel perilymph-specific protein. The purpose of this study was to determine if the CTP detection test is useful for the diagnosis of traumatic PLF. METHODS: This was a prospective study of CTP detection in penetrating middle ear injury cases with tympanic membrane perforation and hearing loss. RESULTS: A total of seven individuals were included in this study. CTP was detected in three of four cases with posterosuperior quadrant perforation of the tympanic membrane. In one of these three cases, even though the high resolution CT scan was not suggestive of PLF and the perilymph leakage could not be visualized intraoperatively, the CTP detection test was able to detect PLF. In two cases, the preoperative positive test results enabled us to make a diagnosis of PLF and a decision for surgical treatment. CTP was not detected in the cases with anterior or inferior tympanic membrane perforation.

CTP (Cochlin-tomoprotein) detection in the profuse fluid leakage (gusher) from cochleostomy.

CONCLUSIONS: By testing 125 samples, we confirmed that Cochlin-tomoprotein (CTP) is present in the perilymph, not in cerebrospinal fluid (CSF). Perilymph and CSF exist in two distinct compartments, even in the case of a malformed inner ear with a bony defect in the lamina cribrosa, as described here. Cochleostomy might have suddenly decreased the perilymph pressure, allowing the influx of CSF into the inner ear resulting in profuse fluid leakage, first perilymph then CSF. OBJECTIVES: The first purpose of this study was to further confirm the specificity of the perilymph-specific protein CTP that we reported recently. Secondly, we assessed the nature of the fluid leakage from the cochleostomy using the CTP detection test. METHODS: A standardized CTP detection test was performed on 65 perilymph and 60 CSF samples. Samples of profuse fluid leakage collected from cochleostomy during cochlear implantation surgery of one patient with branchio-oto-renal (BOR) syndrome were also tested by the CTP detection test. RESULTS: CTP was detected in 60 of 65 perilymph samples but not in any of the CSF samples. The leaked fluid was shown to contain CTP, i.e. perilymph, at the outset, and then the CTP detection signals gradually disappeared as time elapsed.