Eiji Yumoto

Kumamoto University, Kumamoto, Kumamoto Prefecture, Japan

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Publications (165)172.51 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The objective of this study is to evaluate long-term efficacy of refined nerve-muscle pedicle (NMP) flap implantation combined with arytenoid adduction (AA) for treatment of unilateral vocal fold paralysis (UVFP). The authors retrospectively reviewed 33 patients with UVFP who received refined NMP flap implantation with AA and were followed up over a 1-year period. Evaluation of vocal fold vibration (regularity, amplitude, and glottal gap), aerodynamic analysis (maximum phonation time [MPT] and mean airflow rate [MFR]), and perceptual evaluation (Grade and Breathiness) were performed preoperatively and at five different time points (1, 3, 6, 12, and 24 months) postoperatively. All voice parameters improved significantly postoperatively. All parameters except MFR also continued to improve over the course of 24 months. In the videostroboscopic analysis, the parameter for regularity 24 months after surgery was significantly improved compared with that at 1, 3, and 6 months after surgery. There were also significant improvements in amplitude and the glottal gap 24 months after surgery in comparison with values at 3 and 6 months after surgery and 3 months after surgery, respectively. Significant improvement in aerodynamic and perceptual measurements during the follow-up period together with near-normal vocal fold vibration was achieved by delayed reinnervation with refined NMP flap implantation and AA. The combined surgical technique is effective in the treatment of severe breathy dysphonia due to UVFP. Level of evidence 4.
    Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 12/2014; · 1.61 Impact Factor
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    ABSTRACT: The molecular mechanisms controlling the proliferation and differentiation of spiral ganglion cells (SGCs) in the inner ear are still largely unknown. TIS21 is a transcriptional cofactor that shows antiproliferative, antiapoptotic, and prodifferentiative effects on neural progenitor cells. To investigate the function of TIS21 during SGC development, we analyzed SGC neurogenesis from embryonic day 13.5 (E13.5) to postnatal day 4 (P4) in Tis21-GFP knock-in mice, in which the protein-encoding exon of the Tis21 gene was replaced by EGFP. Through E13.5 to P4, we found fewer SGCs in homozygous Tis21-GFP knock-in mice than in wild-type mice. Our results suggest that TIS21 is required for development of SGCs. Deleting Tis21 may affect progenitor cells or neuroblasts at the beginning of cochlear-vestibular ganglion formation and would consequently lead to a decrease in the number of SGCs. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
    Neuroscience Letters 10/2014; 584C:265-269. · 2.06 Impact Factor
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    ABSTRACT: Objective: To establish a rat model with paradoxical vocal fold movement to understand the detailed etiology and physiology of laryngeal synkinesis by evaluating vocal fold movement and by electromyography. Methods: Adult Wistar rats were used. The recurrent laryngeal nerve was transected, anastomosed, and the anastomotic portion was placed in a silicone tube. At 2, 4, and 10 weeks after the treatment (n = 30), we performed laryngoscopy and electromyography. The vocal fold movement was recorded, the hemiglottal area was measured, and the Δarea was calculated by subtracting the area during expiration from that during inhalation. We evaluated the ratio of the Δarea on the treated side to that of the normal side. After laryngoscopy, electromyography of the thyroarytenoid and posterior cricoarytenoid muscles was performed. Results: The mean Δareas were 1.5 ± 3.4%, 2.3 ± 21.5%, and 0.7 ± 31.8% at 2, 4, and 10 weeks after anastomosis, respectively. Eighteen of 18 rats indicated synkinetic reinnervation at 4 and 10 weeks. Regarding vocal fold mobility, 8 of 18 animals showed paradoxical movement, and 5 of 18 exhibited impaired mobility. Conclusion: We have established an animal model of paradoxical movement following recurrent laryngeal nerve injury. This model may be useful in studying laryngeal synkinesis.
    Acta Oto-Laryngologica 10/2014; 134(11). · 0.99 Impact Factor
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    ABSTRACT: Speech perception in noise is still difficult for cochlear implant (CI) users even with many years of CI use. This study aimed to investigate neurophysiological and behavioral foundations for CI-dependent speech perception in noise. Seventeen post-lingual CI users and twelve age-matched normal hearing adults participated in two experiments. In Experiment 1, CI users' auditory-only word perception in noise (white noise, two-talker babble; at 10 dB SNR) degraded by about 15 %, compared to that in quiet (48 % accuracy). CI users’ auditory-visual word perception was generally better than auditory-only perception. Auditory-visual word perception was degraded under information masking by the two-talker noise (69 % accuracy), compared to that in quiet (77 %). Such degradation was not observed for white noise (77 %), suggesting that the overcoming of information masking is an important issue for CI users’ speech perception improvement. In Experiment 2, event-related cortical potentials were recorded in an auditory oddball task in quiet and noise (white noise only). Similarly to the normal hearing participants, the CI users showed the mismatch negative response (MNR) to deviant speech in quiet, indicating automatic speech detection. In noise, the MNR disappeared in the CI users, and only the good CI performers (above 66 % accuracy) showed P300 (P3) like the normal hearing participants. P3 amplitude in the CI users was positively correlated with speech perception scores. These results suggest that CI users’ difficulty in speech perception in noise is associated with the lack of automatic speech detection indicated by the MNR. Successful performance in noise may begin with attended auditory processing indicated by P3.
    Hearing Research 10/2014; · 2.85 Impact Factor
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    ABSTRACT: Optimal glottal closure as well as symmetrical vocal fold masses and tensions are essential prerequisites for normal voice production. Successful phonosurgery depends on restoring these prerequisites to achieve long-term improvement.
    JAMA otolaryngology-- head & neck surgery. 08/2014;
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    ABSTRACT: Abstract Conclusions: Over-adduction of the unaffected vocal fold may not compensate vocal function in unilateral vocal fold paralysis (UVFP). Objective: To determine whether over-adduction of the unaffected vocal fold has any impact on vocal function in patients with UVFP. Methods: A total of 101 patients with UVFP who underwent three-dimensional computed tomographic (CT) examination of the larynx served as subjects. Three-dimensional endoscopic images together with coronal images during phonation were produced to evaluate over-adduction of the unaffected fold, posterior glottal gap, and differences in the vertical position and thickness between the vocal folds. Maximum phonation time (MPT) and mean airflow rate (MFR) were measured. Results: In all, 47 patients showed over-adduction. Their MPT and MFR were 4.9 ± 2.9 s and 653 ± 504 ml/s, respectively. The remaining 54 did not show over-adduction. Their MPT and MFR were 4.7 ± 2.7 s and 574 ± 384 ml/s, respectively. There were no significant differences in MPT or MFR between the two groups. Of the 47 patients with over-adduction, 9 showed no posterior glottal gap. However, their vocal function was not significantly different from that of 38 patients with posterior glottal gap or from that of 43 patients without over-adduction and having a posterior glottal gap.
    Acta Oto-Laryngologica 05/2014; · 0.99 Impact Factor
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    ABSTRACT: To assess laryngeal muscle activity in unilateral vocal fold paralysis (UVFP) patients using laryngeal electromyography (LEMG) and coronal images. Case series with chart review. University hospital. Twenty-one patients diagnosed with UVFP of at least 6 months in duration with paralytic dysphonia, underwent LEMG, phonatory function tests, and coronal imaging. A 4-point scale was used to grade motor unit (MU) recruitment: absent = 4+, greatly decreased = 3+, moderately decreased = 2+, and mildly decreased = 1+. Maximum phonation time (MPT) and mean flow rate (MFR) were employed. Coronal images were assessed for differences in thickness and vertical position of the vocal folds during phonation and inhalation. MU recruitment in thyroarytenoid/lateral cricoarytenoid (TA/LCA) muscle complex results were 1+ for 4 patients, 2+ for 5, 3+ for 6, and 4+ for 6. MPT was positively correlated with MU recruitment. Thinning of the affected fold was evident during phonation in 19 of the 21 subjects. The affected fold was at an equal level with the healthy fold in all 9 subjects with MU recruitment of 1+ and 2+. Eleven of 12 subjects with MU recruitments of 3+ and 4+ showed the affected fold at a higher level than the healthy fold. There was a significant difference between MU recruitment and the vertical position of the affected fold. Synkinetic reinnervation may occur in some cases with UVFP. MU recruitments of TA/LCA muscle complex in UVFP patients may be related to phonatory function and the vertical position of the affected fold.
    Otolaryngology Head and Neck Surgery 02/2014; · 1.72 Impact Factor
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    ABSTRACT: To determine the long-term functional outcomes of type II thyroplasty using titanium bridges for adductor spasmodic dysphonia (AdSD) by perceptual analysis using the Voice Handicap Index-10 (VHI-10) and by acoustic analysis. Fifteen patients with AdSD underwent type II thyroplasty using titanium brides between August 2006 and February 2011. VHI-10 scores, a patient-based survey that quantifies a patient's perception of his or her vocal handicap, were determined before and at least 2 years after surgery. Concurrent with theVHI-10 evaluation, acoustic parameters were assessed, including jitter, shimmer, harmonic-to-noise ratio (HNR), standard deviation of F0 (SDF0), and degree of voice breaks (DVB). The average follow-up interval was 30.1 months. No patient had strangulation of the voice, and all were satisfied with the voice postoperatively. In the perceptual analysis, the mean VHI-10 score improved significantly, from 26.7 to 4.1 two years after surgery. All patients had significantly improved each score of three different aspects of VHI-10, representing improved functional, physical, and emotional well-being. All acoustic parameters improved significantly 2 years after surgery. The treatment of AdSD with type II thyroplasty significantly improved the voice-related quality of life and acoustic parameters 2 years after surgery. The results of the study suggest that type II thyroplasty using titanium bridges provides long-term relief of vocal symptoms in patients with AdSD.
    Auris, nasus, larynx 12/2013; · 0.58 Impact Factor
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    ABSTRACT: Intubation laryngeal granulomas (ILGs) are a well-known complication of endotracheal intubation. Cases other than ILGs can be categorized as unspecified laryngeal granulomas (ULGs) since their etiologies are often difficult to confirm. We intended to clarify clinical features of both ILGs and ULGs and that anticoagulant medication could cause the formation and delayed healing of ILGs in terms of wound-healing delay. We compared the results of our treatment of ILGs (n = 16) and ULGs (n = 47) treated between 1998 and 2009 to characterize these patients. The clinical course, treatment (medical vs. surgical), indications for surgical resection, treatment outcome, and use of anticoagulants for preexisting disease were reviewed and compared between these two groups. The resolution rate was significantly better in ILGs (p < .05). Five ILGs and seven ULGs were surgically resected. The main reason for resection was airway obstruction and the need for histological assessment, respectively. The use of anticoagulants was significantly higher in ILGs than ULGs (8/16 vs. 4/47, p < .01). The resolution period was significantly longer in the ILGs patients with anticoagulant medication compared to that in the ILGs patients without anticoagulant medication (152 ± 101 days vs. 76 ± 44 days, p < .05). ILGs may have different clinical course from ULGs, especially in terms of the resolution period. Moreover, administration of anticoagulants may deter healing of small injury due to intubation. Patients taking anticoagulants should be managed carefully during the perioperative period to prevent the occurrence of ILGs.
    Archives of Oto-Rhino-Laryngology 10/2013; · 1.61 Impact Factor
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    ABSTRACT: To measure the swallowing pressure (SP) of normal subjects using a 2.64-mm-diameter high-resolution manometry (HRM) catheter with 36 circumferential sensors. Repeated measures with subjects serving as controls. Thirty healthy subjects swallowed water at different temperatures and volumes to examine the maximum SP at the velopharynx, meso-hypopharynx, upper esophageal sphincter (UES), and cervical esophagus, and the duration of lowered pressure at the UES. The maximum SP at any location was unaffected by the volume of water, whereas the maximum SP at the UES and cervical esophagus was affected by the temperature. The duration of lowered SP at the UES was significantly prolonged with 10 versus 2 mL of cold water. The pressure curve in males had two peaks (at the velopharynx and UES), whereas that of females had a single peak at the UES. Our data obtained with 2.64-mm HRM demonstrated that as the bolus volume is increased, the duration of lowered SP at the UES is prolonged. The higher maximum SP at the velopharynx in males versus females suggests that there may be a gender difference in pressure at the velopharynx that has not been described previously. This implies that it is necessary to take gender differences into consideration when evaluating the etiology of swallowing dysfunction by examining the SP and SP curve. Moreover, the thinner catheter is less invasive and may contribute to obtaining more physiological measurements. 4 Laryngoscope, 2013.
    The Laryngoscope 09/2013; · 2.03 Impact Factor
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    ABSTRACT: OBJECTIVES/HYPOTHESIS: To quantitate postdeglutitive residue and determine its association with paralysis duration (≤6 vs. ≥6 months) in patients with idiopathic unilateral vocal fold paralysis (UVFP). STUDY DESIGN: Primary institutional retrospective review. METHODS: Twenty patients (mean age, 72 years) with idiopathic UVFP and 13 patients (mean age, 66 years) with isolated recurrent laryngeal nerve paralysis (RLNP) who underwent videofluoroscopic swallow studies (VFSSs) were included. Vallecular and pyriform sinus (PS) residues in the anteroposterior view were analyzed quantitatively. In both regions, the symmetry of the affected versus nonaffected sides between patients with idiopathic UVFP and RLNP were compared. Residual differences between short- versus long-term paralysis duration in idiopathic UVFP patients alone were also evaluated. RESULTS: The affected PS of the idiopathic group demonstrated significantly increased residue (P = .007) as compared with the nonaffected PS, but with no significant difference with respect to the vallecula (P = .183). There was no significant difference in the RLNP group. When compared with RLNP patients, the idiopathic group showed significantly increased residue on the affected PS (P = .002), but differences in the vallecular residue were nonsignificant. Pharyngeal residue and the duration of paralysis in idiopathic UVFP patients were not significantly different. CONCLUSIONS: Idiopathic UVFP patients were more likely to demonstrate increased residue and asymmetry toward the involved region as compared with RLNP patients, suggesting that nerve involvement in idiopathic UVFP may not be exclusive to the RLN. Laryngoscope, 2013.
    The Laryngoscope 05/2013; · 2.03 Impact Factor
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    ABSTRACT: Although numerous causative genes for hereditary hearing loss have been identified, there are no fundamental treatments for this condition. Herein, we describe a novel potential treatment for genetic hearing loss. Because mutations or deletions in the connexin (Cx) genes are common causes of profound congenital hearing loss in both humans and mice, we investigated whether gene supplementation therapy using the wild-type Cx gene could cure hearing loss. We first generated inner ear-specific connexin 30 (Cx30)-deficient mice via the transuterine transfer of Cx30-targeted short hairpin RNA (shRNA-Cx30) into otocysts. The inner ear-specific Cx30-deficient mice mimicked homozygous Cx30-deficient mice both histologically and physiologically. Subsequently, we cotransfected the shRNA-Cx30 and the wild-type Cx30 gene. The cotransfected mice exhibited Cx30 expression in the cochleae and displayed normal auditory functions. Next, we performed the transuterine transfer of the wild-type Cx30 gene into the otocysts of homozygous Cx30-deficient mice, thereby rescuing the lack of Cx30 expression in the cochleae and restoring auditory functioning. These results demonstrate that supplementation therapy with wild-type genes can restore postnatal auditory functioning. Moreover, this is the first report to show that Cx-related genetic hearing loss is treatable by in vivo gene therapy.Molecular Therapy (2013); doi:10.1038/mt.2013.62.
    Molecular Therapy 04/2013; · 6.43 Impact Factor
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    ABSTRACT: We established an animal model of recurrent laryngeal nerve reinnervation with persistent vocal fold immobility following recurrent laryngeal nerve injury. In 36 rats, the left recurrent laryngeal nerve was transected and the stumps were abutted in a silicone tube with a 1-mm interspace, facilitating regeneration. The mobility of the vocal folds was examined endoscopically 5, 10, and 15 weeks later. Electromyography of the thyroarytenoid muscle was performed. Reinnervation was assessed by means of a quantitative immunohistologic evaluation with anti-neurofilament antibody in the nerve both proximal and distal to the silicone tube. The atrophy of the thyroarytenoid muscle was assessed histologically. We observed that all animals had a fixed left vocal fold throughout the study. The average neurofilament expression in the nerve both distal and proximal to the silicone tube, the muscle area, and the amplitude of the compound muscle action potential recorded from the thyroarytenoid muscle on the treated side increased significantly (p < 0.05) over time, demonstrating regeneration through the silicone tube. Recurrent laryngeal nerve regeneration through a silicone tube produced reinnervation without vocal fold mobility in rats. The efficacy of new laryngeal reinnervation treatments can be assessed with this model.
    The Annals of otology, rhinology, and laryngology 01/2013; 122(1):49-53. · 1.05 Impact Factor
  • Haruka Kodama, Yoshihiko Kumai, Momoko Ise, Eiji Yumoto
    Practica Otologica, Supplement 01/2013; 137:102-103.
  • Japan Journal of Logopedics and Phoniatrics 01/2013; 54(1):8-13.
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    ABSTRACT: Intraorbital foreign bodies (IOFBs) are usually accompanied by notable skin wounds and/or ocular wounds, and often there is a clear history of a penetrating object. We report herein on a patient who had an asymptomatic IOFB for 30 years. To the best of our knowledge, there is only one other case of a patient with an IOFB for a longer asymptomatic period after the injury. IOFBs may be overlooked because a small penetrating wound may be accompanied by no signs of inflammation for many decades as in this patient's clinical course.
    Auris, nasus, larynx 11/2012; · 0.58 Impact Factor
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    ABSTRACT: Abstract Conclusions: Three different types of glottal configuration in unilaterally paralyzed larynx were proposed by utilizing three-dimensional computed tomographic (3DCT) images. This new classification might facilitate understanding of the behavior of the affected vocal fold in terms of vocal function. Objectives: To develop a classification of glottal configuration in unilateral vocal fold paralysis (UVFP) based on the thickness and location of the vocal folds utilizing 3DCT and to compare each type of configuration with vocal function. Methods: Thirty-seven consecutive patients with UVFP underwent CT during phonation and inhalation. 3D endoscopic and coronal images on two occasions were produced. Maximum phonation time and mean airflow rate were also measured. Results: Three types of glottal configuration were proposed. The thickness of the affected vocal fold during phonation was equal to or slightly thinner than the healthy fold in 10 patients (type A). The affected fold of the remaining 27 was thin during phonation; they were further classified into types B and C. In type B, the affected fold remained thin during phonation and inhalation (n = 12). Type C was allocated to those showing one or two paradoxical movements of the affected fold (n = 15). Those with type A showed significantly better vocal function.
    Acta oto-laryngologica 11/2012; · 0.98 Impact Factor
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    ABSTRACT: OBJECTIVES/HYPOTHESIS: To evaluate the impact of nimodipineon reinnervation of the long-term denervated rat thyroarytenoid (TA) muscle following nerve-muscle pedicle flap (NMP) implantation. STUDY DESIGN: Quantitative histologic and physiologic assessments. METHODS: Using 120 Wistar rats, we performed NMP implantation at different times after transection of the left recurrent laryngeal nerve (RLN). Sixty animals received nimodipine treatment (NIMO [+] group), and the remaining 60 animals received no nimodipine treatment (NIMO [-] group). As a control, an additional 28 animals were subjected only to transection of the left RLN (DNV group). Subgroups were assigned based on the period after RLN transection (0 [immediate], 8, 16, and 32 weeks). In the DNV group, we assessed histologically the muscle area, axons, neuromuscular junctions (NMJs), and myosin heavy chains (MyHC) type IIA and IIB in the TA muscle. In the NIMO (-) and NIMO (+) groups, histologic assessments and evoked electromyography were performed on the TA muscle at 10 weeks post-NMP implantation. RESULTS: In 8-week interval subgroups, the muscle fiber area and the number of NMJs in the NIMO (+) group were significantly greater than in the NIMO (-) group (P < 0.05, each). In the 0-week and 32-week interval subgroups, the muscle fiber subtype changed significantly, from IIA to IIB (P < 0.01 and P < 0.05, respectively); and, at all time-points the muscle fiber area, number of NMJs, and action potentials in the TA muscle tended to be greater in the NIMO (+) group than in the NIMO (-) group. CONCLUSIONS: Nimodipine expedited the effects of NMP implantation on reinnervation of the long-term denervated TA muscle. Laryngoscope, 2012.
    The Laryngoscope 09/2012; · 2.03 Impact Factor
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    ABSTRACT: Arytenoid adduction (AA) as surgical treatment for unilateral vocal fold paralysis (UVFP) is associated with higher morbidity from airway complications due to postoperative laryngeal edema compared with other laryngeal framework surgeries. The aim of this study was to evaluate postoperative laryngeal edema after AA using a new videolaryngoscopic (VL) scoring assessment. Prospective case series. Nineteen patients with UVFP (14 males and five females; mean age, 56 years) who were treated with AA alone or combined with ansa cervicalis (AA/AC) nerve anastomosis or nerve-muscle pedicle (AA/NMP) flap implantation were evaluated. Laryngeal edema was assessed by VL scoring for 10 days postoperatively. Degree of edema was scored in three subsites: the membranous vocal fold, arytenoid mound, and pyriform sinus on the operated side. Statistical significance was defined as P < .05. No patient experienced postoperative airway compromise. Interexaminer reliability was generally high (Spearman r > 0.75). The mean degree of edema increased steadily from postoperative day (POD) 1 to 3, peaking on POD 3 at all subsites. It then declined significantly from POD 3 to 7 (P < .05) and gradually through POD 10. The maximum degree of edema, maximum edema time, and operative time were not correlated significantly at any subsite. Maximum edema time and surgery type (AA vs. AA/AC or AA/NMP) were not correlated at any subsite. Inter-rater reliability for the proposed VL scoring was significant at all subsites. The VL findings suggest that AA alone or AA combined with reinnervation showed maximum laryngeal edema on POD 3 but added no significant morbidity.
    The Laryngoscope 03/2012; 122(5):1104-8. · 2.03 Impact Factor
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    ABSTRACT: To determine whether nimodipine, an L-type voltage-operated calcium channel antagonist that is an accelerator of axonal regeneration following peripheral nerve injury, can expedite reinnervation of denervated rat thyroarytenoid (TA) muscle following nerve-muscle pedicle (NMP) flap implantation. A quantitative histologic and physiologic assessment of the TA muscle following NMP flap implantation, with or without nimodipine treatment. Using 72 Wistar rats, we performed a transection on the left recurrent laryngeal nerve, followed by NMP flap implantation. Thirty-six animals received nimodipine treatment (NIMO [+] group), and the remaining 36 animals received no nimodipine treatment (NIMO [-] group). As a control, 18 animals were subjected only to transection of the left recurrent laryngeal nerve. We performed a histologic assessment for muscle area, axon, nerve terminals (NTs), and acetylcholine receptors (AchRs) in the TA muscle and electromyography at 2, 4, and 10 weeks after surgery. Muscle area, ratio of the number of NTs to that of AchRs (NT/AchR ratio), and evoked action potential in the TA muscle were significantly greater in the NIMO (+) group than in the NIMO (-) group (P < .05) at 4 weeks. At 10 weeks, the NT/AchR ratio was significantly greater in the NIMO (+) group than in the NIMO (-) group (P < .05). We found that nimodipine accelerated reinnervation of the denervated TA muscle following NMP flap implantation.
    The Laryngoscope 03/2012; 122(3):606-13. · 2.03 Impact Factor

Publication Stats

674 Citations
172.51 Total Impact Points


  • 1999–2014
    • Kumamoto University
      • • Department of Otolaryngology-Head and Neck Surgery
      • • School of Medicine
      Kumamoto, Kumamoto Prefecture, Japan
  • 2000–2013
    • The Australian Society of Otolaryngology Head & Neck Surgery
      Evans Head, New South Wales, Australia
  • 2011–2012
    • Sohag University
      Sawhāj, Sūhāj, Egypt
  • 1990–1998
    • Ehime University
      • • Department of Otolaryngology
      • • School of Medicine
      Matuyama, Ehime, Japan