Characteristics of repeated recidivism in surgical cases of cholesteatoma requiring canal wall reconstruction.

OBJECTIVE: Few reports discuss the characteristics of repeated recidivism of cholesteatoma. We describe the clinical characteristics of patients with cholesteatoma who experienced at least two recidivism episodes after initial surgery for cholesteatoma requiring canal wall reconstruction. METHODS: We reviewed the medical records of 11 patients who underwent surgery for cholesteatoma with canal wall reconstruction at our department between April 2008 and March 2018 and subsequently experienced two relapses that necessitated revision surgery involving tympanomastoidectomy with canal reconstruction. Patient age at the time of the first surgery ranged from 6 to 56 (mean, 25.7) years. Seven (63.6%) of the 11 patients were male. These 11 patients were classified according to the type of recidivism, and their characteristics (pathology, operation date, operation method, pattern of relapse, and position of recurrence) were investigated. RESULTS: Four cases involved secondary residual cholesteatoma, with the mean interval between the first revision surgery and the second revision surgery being 23.8 (range, 11-39) months. Secondary residual sites included the anterior tympanic cavity, tympanic sinus, and anterior end of the reconstructed cartilage of the canal wall. The other seven cases involved secondary recurrence, with the mean interval between the first and the second revision surgery being 26.1 (range, 12-57) months. The sites of recurrence were at the edges of the reconstructed cartilage. One notable case involved the cartilage junction, leading us to hypothesize that retraction of the temporal muscle flap and the patulous Eustachian tube was the underlying cause. CONCLUSION: For residual cholesteatoma, strict measures are necessary to maintain the operation under clear view, and more careful follow-up is necessary in patients who have had previous surgery at another hospital. For recurrent cholesteatoma, it was recognized that Eustachian tube function must be ascertained in advance, and careful observation of the reconstructed cartilage edge is necessary.

A Case of Cochlear Implantation in a Patient with Superficial Siderosis.

Superficial siderosis is a disease in which iron from hemoglobin is deposited in the central nervous system, resulting in conditions such as progressive sensorineural hearing loss, cerebellar ataxia, dementia, and pyramidal signs. A 30-year-old man with superficial siderosis received a cochlear implant in the left ear, which had shown complete hearing loss. Good auditory responses were obtained at 14 days after implantation. The postoperative average hearing level with the cochlear implant was 56.7 dB at 3 months and 55.0 dB at 6 months. However, the patient showed gradual hearing loss, and the dynamic range changed each time the electrode parameters were adjusted. To assess residual hearing ability, single-photon emission computed tomography was performed together with an assessment of electrical auditory brainstem response, which showed a good response and increased blood flow in both the temporal lobes. Based on this result, we asked the patient to continue using the cochlear implant to see whether a perception of speech response would be obtained. However, the patient discontinued using the cochlear implant because he could not hear satisfactorily. Hearing outcomes after cochlear implant surgery for patients with superficial siderosis are not necessarily good. Therefore, the possibility of unsatisfactory results should be fully explained before recommending this surgery to patients.

A Case of Skull Base Chondrosarcoma with Intraoperative Trigemino-Cardiac Reflex.

A 75-year-old female patient presented with a suspected recurrence of a clival chordoma. The tumor was resected using the infratemporal fossa type B and anterior petrosal approach with the help of a neurosurgeon. During cauterization of the trigeminal nerve, the patient developed cardiac arrest for approximately 10 seconds because of the trigemino-cardiac reflex (TCR). After several sternal compressions, there was return of spontaneous circulation. The operation was resumed after the circulatory dynamics stabilized. Subsequently, the surgery was completed with partial resection of the tumor without the recurrence of cardiac arrest. The pathological diagnosis was chondrosarcoma, and postoperative treatment with radiotherapy was started. Stimulation of the sensory branches of the trigeminal nerve induces TCR. There are reports of TCR developing in approximately 10% of skull base surgery cases in the absence of atropine administration. We report a rare case of TCR during the surgical procedure for the treatment of a skull base chondrosarcoma.

Sequential motion of the ossicular chain measured by laser Doppler vibrometry.

OBJECTIVE: In order to help a surgeon make the best decision, a more objective method of measuring ossicular motion is required. METHODS: A laser Doppler vibrometer was mounted on a surgical microscope. To measure ossicular chain vibrations, eight patients with cochlear implants were investigated. To assess the motions of the ossicular chain, velocities at five points were measured with tonal stimuli of 1 and 3 kHz, which yielded reproducible results. The sequential amplitude change at each point was calculated with phase shifting from the tonal stimulus. Motion of the ossicular chain was visualized from the averaged results using the graphics application. RESULTS: The head of the malleus and the body of the incus showed synchronized movement as one unit. In contrast, the stapes (incudostapedial joint and posterior crus) moved synchronously in opposite phase to the malleus and incus. The amplitudes at 1 kHz were almost twice those at 3 kHz. CONCLUSIONS: Our results show that the malleus and incus unit and the stapes move with a phase difference.

Analysis of Direct Simultaneous Measurement of Glottal Airflow Velocity, Subglottal Pressure, and High-Speed Imaging Using Flexible Transnasal Endoscope in a Human Subject.

It is difficult to directly observe glottal airflow velocity just above the glottis due to sensor size requirements and limited accessibility. We developed a miniature hot-wire probe and flexible fiberscopic high-speed imaging system for human examinations. Simultaneous direct measurement of glottal airflow velocity, subglottal pressure, and vocal fold vibration was achieved in a patient who was treated with a T-tube for tracheal stenosis. Airflow velocity changes at the anterior midline of the vocal folds were synchronized with subglottal pressure changes during each phonation cycle. The velocity at the anterior midline of the vocal folds showed a rhythmic pattern of sharp, high peaks. The result of fast Fourier transform analysis indicated that glottal velocity at the anterior midline of the vocal folds had abundant high-frequency components that were not affected by resonance of the vocal tract. Airflow velocity was variable and diminished except at the anterior midline of the vocal folds.

Staged resection for vestibular schwannoma.

CONCLUSION: Surgery remains the preferred option for large vestibular schwannoma (VS). The presence of unpredictable intraoperative difficulties may convince the operator to suspend the surgery to avoid risks to patient life. Additional surgeries may be mandatory and are better performed using a transcochlear approach. High rates of complications, poor facial nerve results, and a percentage of incomplete removals should be expected in such unfavorable cases. OBJECTIVES: To review the results for nine cases of huge VS treated by staged resection. METHOD: A retrospective case review was performed for all nine patients who underwent staged resection of VS at the Gruppo Otologico between 1984-2012. The decision to perform staged surgery was always made intra-operatively after encountering unpredicted difficulties. RESULTS: The nine patients represented 0.3% of all patients who underwent VS surgery during the same period. Mean tumor size was 4.7 cm (range = 3.0-6.6 cm). Two cases required three surgeries, resulting in a total of 20 operations. In addition, two cases required pre-operative ventriculoperitoneal shunt and one required temporary tracheotomy. After the final stage of surgery, complete removal had been achieved in six of the nine patients. The facial nerve was never preserved anatomically.

Dietary glucosylceramides suppress tumor growth in a mouse xenograft model of head and neck squamous cell carcinoma by the inhibition of angiogenesis through an increase in ceramide.

BACKGROUND: We previously reported that dietary glucosylceramides show cancer-prevention activity in a mouse xenograft model of human head and neck cancer cells (SCCKN). However, the mechanism was unclear. Ceramides, metabolites of glucosylceramides, induce apoptotic cell death in various malignancies. Here, we investigated the inhibitory effects of dietary glucosylceramides on tumor growth in vivo and in vitro. METHODS: SCCKN were subcutaneously inoculated into the right flanks of NOD/SCID mice. Mice were treated with or without dietary glucosylceramides (300 mg/kg) daily for 14 consecutive days after confirmation of tumor progression. Microvessel areas around the tumor were assessed by hematoxylin-eosin staining and immunohistochemistry of CD31, and, as markers for angiogenesis, protein levels of VEGF, VEGF receptor-2, and HIF-1α were assessed by Western blotting. Mass spectrometry was performed to measure the levels of sphingolipids in mouse serum after treatment with dietary glucosylceramides. RESULTS: Oral administration of glucosylceramides significantly decreased SCCKN growth in the xenograft model with inhibition of angioinvasion. In tumor-invasive areas, VEGF and HIF-1α in the tumor cells, and VEGF receptor-2 in endothelial cells decreased after treatment with dietary glucosylceramides. Dietary glucosylceramides increased serum levels of sphingosine-based ceramides as compared to the control. In SCCKN and UV♀2 cells, C6-ceramide suppressed the expressions of VEGF, VEGF receptor-2, and HIF-1α in vitro. CONCLUSION: These results suggest that dietary glucosylceramides trigger the de novo pathway of ceramide synthesis, indicating that sphingosine-based ceramide suppresses the growth of head and neck tumors through the inhibition of pro-angiogenic signals such as VEGF, VEGF receptor-2, and HIF-1α.

Usefulness of chest CT scan for head and neck cancer.

OBJECTIVE: Chest computed tomography (CT) is not performed routinely or worldwide as the initial diagnostic procedure for patients with head and neck cancer (HNC). The significance of the chest CT scan for HNC diagnosis has not been thoroughly defined. The present study reports findings in an effort to broaden the acceptance and application of CT for HNC. METHODS: Using medical records, we assessed initial chest CT scans of the patients with new-onset HNC between April 2004 and March 2010. The results were classified into three groups: nodules ≥ 1 cm, small nodules (< 1 cm) that were indeterminate and normal lungs without nodules. Lung nodules that increased in size and/or number at follow-up were regarded as malignant. First, the sensitivity of X-ray and CT for detection of lung nodules in patients with HNC was compared. Second, the nodules were estimated to be malignant or not malignant by follow-up chest CT. Third, statistical analyses were performed to determine the association between variables and distant lung metastases in patients with head and neck squamous cell carcinoma. RESULTS: In total, 332 patients underwent a chest CT scan as part of the initial examination. Lung nodules were detected on the initial chest CT in 77 patients: in contrast, lung nodules were detected on the initial chest X-ray in only five patients. On initial chest CT scans, lung nodules ≥ 1 cm were observed in 10 patients, small solitary lung nodules were observed in 67 patients, and lungs without nodules were observed in 255 patients. Lung nodules were detected in 77 (23.2%) patients, 25 (32.5%) of whom had malignant lung nodules. Moreover, in 18/67 patients (26.9%), small lung nodules initially classified as indeterminate were determined as malignant at follow-up. However, 30/255 patients (11.8%) without nodules at initial diagnosis developed lung nodules at follow-up. T3 or T4 disease (P = 0.006), N2 or N3 disease (P < 0.001) and stage 3 or 4 disease (P = 0.001) individually and significantly correlated with the development of lung metastases. In addition, lung nodules in initial CT scans (P = 0.004) and other distant metastases (P < 0.001) were significant predictors for the development of lung metastases at follow-up. CONCLUSION: Initial chest CT scan is recommended for patients with advanced HNC. Further, patients with advanced HNC with or without lung nodules, as detected on initial chest CT scans, should be followed up with additional scanning.

Sequential multipoint motion of the tympanic membrane measured by laser Doppler vibrometry: preliminary results for normal tympanic membrane.

BACKGROUND: Numerous studies have reported sound-induced motion of the tympanic membrane (TM). To demonstrate sequential motion characteristics of the entire TM by noncontact laser Doppler vibrometry (LDV), we have investigated multipoint TM measurement. MATERIALS AND METHODS: A laser Doppler vibrometer was mounted on a surgical microscope. The velocity was measured at 33 points on the TM using noncontact LDV without any reflectors. Measurements were performed with tonal stimuli of 1, 3, and 6 kHz. Amplitudes were calculated from these measurements, and time-dependent changes in TM motion were described using a graphics application. RESULTS: TM motions were detected more clearly and stably at 1 and 3 kHz than at other frequencies. This is because the external auditory canal acted as a resonant tube near 3 kHz. TM motion displayed 1 peak at 1 kHz and 2 peaks at 3 kHz. Large amplitudes were detected in the posterosuperior quadrant (PSQ) at 1 kHz and in the PSQ and anteroinferior quadrant (AIQ) at 3 kHz. The entire TM showed synchronized movement centered on the PSQ at 1 kHz, with phase-shifting between PSQ and AIQ movement at 3 kHz. Amplitude was smaller at the umbo than at other parts. In contrast, amplitudes at high frequencies were too small and complicated to detect any obvious peaks. CONCLUSION: Sequential multipoint motion of the tympanic membrane showed that vibration characteristics of the TM differ according to the part and frequency.

Analysis of human glottal velocity using hot-wire anemometry and high-speed imaging.

OBJECTIVES: The aim of this study was to analyze glottal velocity and glottal opening and closure. For this purpose, we developed a miniature, flexible, hot-wire probe that can make truly instantaneous measurements of the human larynx in vivo. METHODS: A miniature hot-wire tip was inserted into a flexible transnasal endoscope. Fiberscopic examination was performed transnasally so that we could observe glottal vibration using high-speed imaging. The tip of the hot-wire probe was placed just above the glottis. The position of the probe was carefully monitored and checked with another flexible endoscope. RESULTS: Changes in velocity were recorded periodically. The velocity was higher in close proximity to the vocal folds. High-speed motion pictures were taken at a rate of 2000 frames per second with an auxiliary light source. CONCLUSIONS: Quantitative analysis of glottal velocity is required to improve our understanding of the relationship between laryngeal physiology and acoustics in humans. To solve the problem of synchronization inaccuracy, glottal velocity was captured instantaneously in the high-speed imaging system's processor memory.

[Problems in the evaluation of hearing of infants].

Infant hearing loss should be identified early to prevent delays in the development of speech and language. However, evaluation of hearing of infants is not so easy, because training is required to estimate auidiometric thresholds from behavioral testing such as conditioned orientation response audiometry (COR). Most ENT physicians who are not capable of behavioral testing tend to evaluate hearing of infants only from testing auditory brainstem response (ABR). Information about the infant's auditory response to the environmental sounds could be obtained easily and might be a substitute for a behavioral testing. We administered a questionnaire to the parents to obtain accurate information about the infant's auditory response. Tanaka-Shindo's developmental battery test of auditory function is an established questionnaire with various questions about auditory response and development of speech according to the age of infants from 0-15 month. We administered Tanaka-Shindo's questionnaire to the parents of infants before 8 months, and administered the following questionnaire to the parents of infants over 8 months. (1) If you call out the child's name from behind, does the child turn his/her head? (2) Does the child turn his/her head to any sounds on television, to any small sounds (for example: listened when someone opens the door or opens wrapping paper), or to beeping sounds from electric devices? To investigate the clinical usefulness of the questionnaire to estimate hearing in infants, 79 children (under 4 y.o.) evaluated their hearing at the Tottori University Hospital were studied. Forty-three out of 45 (95.6%) who had normal hearing had yes in the questionnaire, but the 18 who had moderate to severe (60 dB) hearing loss did not have yes in the questionnaire. For the mentally retarded 33 children, 27 out of 29 (93%) who had normal hearing had yes in the questionnaire, but the 4 who had moderate to severe hearing loss did not have yes in the questionnaire. Questionnaire about the infant's auditory response is useful to differentiate between normal hearing and moderate to severe hearing loss. We recommend our questionnaire as screening procedure to most ENT physicians to identify hearing loss in infants. It is important refer patients not evaluated as normal to an ENT physician who is capable of diagnosing the hearing of infants by behavioral testing.

[Managing small pulmonary nodules in head and neck malignant tumors].

The recent increase in the use of helical CT has produced a higher detection rate of small pulmonary nodules than in conventional CT application, and has presented a serious problem in their treatment. We carried out a retrospective study to identify a clinical standard in the management of those nodules in head and neck malignant tumors. The subjects were 108 in-and out patients (87 men and 21 women) with head and neck malignant tumors who received radiation therapy in our university hospital between 2003 and 2004 (ages ranging from 25 to 93 years; mean, 66 years). Helical CT of the chest was applied to 92 patients of the 108 (85%). We determined small pulmonary nodules as round nodules 5 mm or more and less than 1 cm in diameter, and observed them in 14 of the 92 (15%). Firstly, we compared nodule growth by dividing the patients into 2 groups. The nodules grew in 2 of 7 patients of Group I, where chemotherapy was not done or where chemotherapy was not effective on the primary tumor, and in 3 of 7 patients of Group II, where chemotherapy was effective on the primary tumor. Secondly, disregarding the effects of chemotherapy, we analyzed nodule growth: the nodules grew in 5 of the 14 patients (36%). Those small pulmonary nodules were all pulmonary metastases. When small pulmonary nodules are detected by helical CT, accompanying malignant tumors of the head and neck, and bearing in mind the probability of their growth of at least 36%, we should therefore follow them up carefully.

[Hearing outcome of canal wall reconstruction tympanoplasties for the treatment of cholesteatoma].

While the hearing outcome of patients undergoing a tympanoplasty with canal reconstruction is generally thought to be inferior to that of patients undergoing a canal-up tympanoplasty, a direct comparison of these two procedures, performed by the same operator, has not been reported. Consequently, we compared the hearing outcomes of these two techniques and discussed the postoperative complications that could accompany the procedures. Hearing was evaluated in 52 ears with middle ear cholesteatoma. Using the postsurgical hearing result assessment criteria published by the Japanese Society of Otology in 2000, hearing was then evaluated again at least 6 months after surgery. When the data was analyzed according to the type of operation, the success rates (as determined using the above assessment criteria) were 78.6% for type I, 88.5% for modified type III, and 50.0% for modified type IV. The success rate for the modified type III operations was superior to that of the modified type IV operations, and the incidence of a postoperative air-bone gap in the type IV tympanoplasties was significantly larger than that in other groups. Procedures involving external auditory canal surgery can be particularly problematic for the treatment of cholesteatoma. In this series, the same author (KH) performed all the canal-up tympanoplasty procedures that took place during 1990-1996, and all other tympanoplasties, mainly canal reconstruction procedures, that took place during 1998-2001. The success rate was 68.4% (13/19) for the canal-up tympanoplasties, 100% (8/8) for the atticotomies and 76% (19/25) for the canal wall reconstructions. The postoperative success rate in the atticotomy group was significantly higher than the rates of the other groups. Among the canal reconstructive tympanoplasty procedures, a second exploratory surgery was performed in 15/24 cases, and residual cholesteatoma was observed in 3 cases. The major postoperative complications were epitympanic pocket formation (12/24) and taste disturbances, caused by chordal damage (2/24). These findings indicate that tympanoplasties with canal reconstruction improve the hearing outcome, compared with the outcome of canal-up tympanoplasties. However, epitympanic retraction pocket formation, resulting in recurrent cholesteatoma, is a possible complication of both surgical procedures, and new approaches or techniques should be sought to minimize such postoperative changes.