H Kojima

Kyoto University, Kyoto, Kyoto-fu, Japan

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Publications (68)69.4 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: This report describes a very rare case of myasthenia gravis (MG) localized to the larynx, with the onset of dyspnea requiring tracheotomy. The vocal cords of this patient were fixed in the paramedian position. Under fiberscopic observation, improvement of laryngeal function was demonstrated after intravenous injection of edrophonium. However, no voice change occurred. The posterior crico-arytenoid muscle has the sole responsibility of abducting the vocal cord; thus, it is concluded that the dyspnea was caused by the selective paralysis of this muscle. We suggest that MG should be considered in cases of vocal cord paralysis of unknown etiology.
    Auris Nasus Larynx 10/2007; 34(3):401-3. · 0.95 Impact Factor
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    ABSTRACT: A new operative technique for the treatment of floppy epiglottis is introduced in this report. Though its diagnosis is not so difficult by close observations using a flexible fiberscope, it is likely to be treated as an asthma attack or a paradoxical vocal cord movement. In previous reports of upper airway obstruction caused by adult floppy epiglottis: epiglottis prolapse during inspiration, the cause of this condition has been divided broadly into two categories: idiopathic cases and secondary cases. Partial or total epiglottectomy has been usually reported for the treatment of the relief of airway obstruction caused by a floppy epiglottis. It is very difficult to decide adequately how much volume of epiglottis to cut without postoperative sequelae. A V-shaped partial epiglottidectomy is described for its treatment. This technique is very easy, simple, and effective.
    Auris Nasus Larynx 09/2007; 34(3):409-11. · 0.95 Impact Factor
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    ABSTRACT: To evaluate the effectiveness of hyperfractionation for T2 glottic cancer from a viewpoint of laryngeal preservation, we analyzed 21 patients (twice-a-day group) who were treated with hyperfractionation between 1992 and 1998 and compared the results with those of 27 patients (once-a-day group) treated with conventional once-a-day radiation between 1987 and 1992. In the twice-a-day group, radiation was performed with two fractions of 1.2 Gy/day up to a total dose of 72-74.4 Gy. In the once-a-day group, radiation was performed with a fraction of 2 Gy/day up to a total dose of 66 Gy. If radiation was ineffective at 40 Gy, it was stopped, and surgical treatment was carried out. Kaplan-Meier estimates were used for the analysis of the survival rate and laryngeal preservation rate, and the results were compared. In the once-a-day group, the 5-year survival rate was 92.3%. The 5-year laryngeal preservation rate was 51.8%, and it was 60.3% in 20 patients who had undergone full-dose radiation (once-a-day full-dose group). In the twice-a-day group, no major complication, such as laryngeal necrosis, was seen in any case, and the 5-year survival rate was 95.3%. The 5-year laryngeal preservation rate was 95.3%, and it was significantly better than that of both the once-a-day group and the once-a-day full-dose group. Hyperfractionation is considered to be useful for preserving the larynx for the treatment of T2 glottic cancer.
    Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 03/2006; 263(2):144-8. · 1.46 Impact Factor
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    ABSTRACT: Since 1990, we have performed steroid injection into the vocal fold by fiberoptic laryngeal surgery (FLS) under local anesthesia. In this study, the usefulness of this method was evaluated in 28 patients with vocal nodules. Under monitoring using a fiberoptic laryngoscope, a curved injection needle was inserted via the oral cavity and steroid was injected. Endoscopic findings showed that the vocal nodule had disappeared in 17 patients of the 27 patients and decreased in 10 after injection. The maximum phonation time was 10.9 s before operation and 13.9 s after operation, showing a significant increase (P<0.05), and the mean flow rate also showed a significant improvement (P<0.05). The patients self-rating concerning hoarseness demonstrated great improvement after injection. This technique can be performed under local anesthesia in combination with voice therapy on an outpatient basis, and it is considered to be useful for treating vocal nodules.
    Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 10/2004; 261(9):489-92. · 1.46 Impact Factor
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    ABSTRACT: The purpose of the present study was to evaluate the efficacy of cricoid regeneration via in situ tissue engineering in a canine larynx for the treatment of subglottic stenosis. As the tissue scaffold, a Marlex mesh tube coated by collagen sponge was used for a rigid airway framework and for tissue regrowth around the tube. On 5 dogs, the larynx was exposed and the anterior third of the cricoid cartilage was resected. The tube was anastomosed to the lower edge of the thyroid cartilage and to the first tracheal cartilage. By postoperative endoscopic examination at 3 to 7 months, no airway obstruction was observed in any of the dogs. There was granulation tissue in 2 dogs and slight mesh exposure in 1 dog, but they were asymptomatic. Confluent regeneration of the epithelium over the scaffold and good incorporation of the scaffold mesh into the host tissue were observed after surgery.
    The Annals of otology, rhinology, and laryngology 09/2004; 113(8):623-7. · 1.21 Impact Factor
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    ABSTRACT: The aim of this study was to regenerate the injured vocal fold by means of selective cultured autologous mesenchymal stem cells (MSCs). Eight adult beagle dogs were used for this experiment. Selective incubation of MSCs from bone marrow was done. These MSCs were submitted to 3-dimensional incubation in 1% hydrochloric acid atelocollagen. Three-dimensional incubated MSCs were injected into the left vocal fold, and atelocollagen only was injected into the right vocal fold of the same dog as a control. Four days after injection, the posterior parts of the vocal folds were incised. The regeneration of the vocal fold was estimated by morphological and histologic evaluations. Our results showed that 3-dimensional incubated MSCs were useful in the regeneration of the injured vocal fold. This study shows that damaged tissues such as an injured vocal fold would be able to be regenerated by tissue engineering.
    The Annals of otology, rhinology, and laryngology 12/2003; 112(11):915-20. · 1.21 Impact Factor
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    ABSTRACT: The recurrent laryngeal nerve (RLN) does not regenerate well after it has been cut, and no current surgical methods achieve functional regeneration. Here, we evaluate the functional regeneration of the RLN after reconstruction using a biodegradable nerve conduit or an autologous nerve graft. The nerve conduit was made of a polyglycolic acid (PGA) tube coated with collagen. A 10-mm gap in the resected nerve was bridged by a PGA tube in 6 adult beagle dogs (group 1) and by an autologous nerve graft in 3 dogs (group 2). Fiberscopic observation revealed functional regeneration of the RLN in 4 of the 6 dogs in group 1. No regeneration of the RLN was observed in any dog in group 2. We also tested for axonal transport, and measured the compound muscle action potential. The RLN can be functionally regenerated with a PGA tube, which may act as a scaffold for the growth of regenerating axons.
    The Annals of otology, rhinology, and laryngology 07/2003; 112(6):492-8. · 1.21 Impact Factor
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    ABSTRACT: We examined cortical activation by speech in patients with moderate inner ear hearing loss using PET to investigate the response of the language network to insufficient speech input. We made two word lists, well-perceived words and poorly-perceived words, and measured rCBF during monaural presentation of these words. Well-perceived words activated bilateral temporal lobes, bilateral inferior frontal gyri (IFG) and left angular gyrus (AG) regardless of the ear stimulated, Poorly-perceived words activated contralateral temporal lobe and bilateral IFG, while little or no activation was observed in the ipsilateral temporal lobe and left AG. Insufficient activation of the temporal lobe ipsilateral to the ear stimulated might correlated with less accurate word comprehension in patients with inner ear hearing loss.
    Neuroreport 05/2003; 14(5):763-7. · 1.40 Impact Factor
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    ABSTRACT: Since 1990, we have performed steroid injections into the vocal fold under topical anesthesia using fiberoptic laryngeal surgery (FLS) in an outpatient clinic. The aim of this study was to retrospectively assess the usefulness of this treatment method in 44 patients with mild Reinke's edema. Using fiberoptic monitoring of the larynx, a curved injection needle was inserted via the oral cavity and triamcinolone acetonide was injected into Reinke's space of the bilateral vocal fold. Remission or improvement was observed in almost all patients in terms of both patients' self-rating of hoarseness and endoscopic vocal fold findings The maximum phonation time was a mean of 9.0 s before operation and 11.4 safter operation, and this increase was significant (p < 0.01). Voice pitch also improved, from 168 to 181 Hz, in female patients, and this increase was also significant (p < 0.05). Steroid injection is considered to be useful for treating mild Reinke's edema.
    Acta Oto-Laryngologica 04/2003; 123(3):417-20. · 1.11 Impact Factor
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    ABSTRACT: Descending necrotizing mediastinitis occurs secondary to deep neck infection, and the primary focus of infection is mostly located in the tonsil, pharynx and carious tooth. DNM following acute epiglottitis is quite rare, with only one case reported. We treated an 84-year old female with an acute epiglottitis followed by DNM. She was successfully treated by drainages with cervical surgery combined with thoracotomy and cervical surgery.
    Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 04/2003; 260(3):128-30. · 1.46 Impact Factor
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    ABSTRACT: We developed a technique of fiberoptic laryngeal surgery for the treatment of vocal process granulomas. In this system, the granuloma can be removed relatively easily and repeatedly under topical anesthesia on an outpatient basis. We treated 27 patients for a total of 4 intubation granulomas and 23 contact granulomas. Ten of the 23 contact granulomas recurred after the initial surgery, but the intubation granulomas did not recur. Most of the recurrent lesions were resolved by fewer than 3 procedures, and all patients were finally cured. Although conservative therapies such as voice therapy and proton pump inhibitors have recently prevailed, surgical removal remains useful in treating vocal process granulomas. Fiberoptic laryngeal surgery facilitates repeated surgical procedures.
    The Annals of otology, rhinology, and laryngology 10/2002; 111(9):789-93. · 1.21 Impact Factor
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    ABSTRACT: We designed a new type of nonlinear digital hearing aid (TD-1) with near-instantaneous amplitude compression for sensorineural hearing-impaired people. The amplification method utilized by the TD-1 normalizes the signal waveforms within a time window bounded by two adjacent positive going zero-crossing points. The signals within this window are amplified so that the maximum amplitude reaches a preset value, thus allowing a consistent peak amplitude to be maintained. To test this, we examined the efficacy of the TD-1 device in 31 patients with sensorineural hearing loss. When tested for recognition of Japanese sentences in a quiet environment, 7 of 25 (28.0%) subjects wearing the TD-1 showed a 20% or greater increase in the maximum intelligibility score than that obtained when wearing their own linear hearing aids. In addition, 7 of 31 (22.6%) subjects showed the same increase with the TD-1 relative to that obtained when they wore HA70 or HA73 devices (Rion Co., Ltd., Tokyo, Japan), which are conventional analogue hearing aids. These results indicate that TD-1 can be effective for patients with sensorineural hearing loss.
    Archiv für Klinische und Experimentelle Ohren- Nasen- und Kehlkopfheilkunde 01/2002; 258(10):523-8. · 1.46 Impact Factor
  • Nihon Kikan Shokudoka Gakkai Kaiho 01/2002; 53(1):45-48.
  • The Annals of otology, rhinology & laryngology. Supplement 01/2001; 185:12-4.
  • Asaio Journal - ASAIO J. 01/2001; 47(2).
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    ABSTRACT: The etiology of spasmodic dysphonia (SD) is still unknown. In the present study, cortical function of a 59-year-old male patient with adductor type SD was examined during phonation with positron emission tomography (PET). Magnetic resonance imaging showed no organic abnormality in the brain. However, PET showed remarkable activities during phonation in the left motor cortex, Broca's area, the cerebellum, and the auditory cortices, whereas the supplementary motor area (SMA) was not activated. The SMA is known to function for motor planning and programming and is usually activated in normal phonation. Several previous reports have shown that the damage of the SMA caused a severe disturbance of voluntary vocalization. In the present case, it was suggested that the functional deficit of the SMA might be related to SD.
    American Journal of Otolaryngology 01/2001; 22(3):219-22. · 1.23 Impact Factor
  • Nihon Kikan Shokudoka Gakkai Kaiho 01/2001; 52(1):24-27.
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    ABSTRACT: it is believed that the number of neurons of the human cortex increases rapidly in the first postnatal year, and then decreases gradually towards adult level as their functions are revised up to 11 years of age ('synaptic revision'). It is also confirmed that regional cerebral blood flow (rCBF) at rest represents the density of the neurons and decreases in accordance with the synaptic revision in process. If synaptic revision does not occur, rCBF remains at high level. Thus, we can evaluate whether functional differentiation has occurred in the human cortex by measuring rCBF at resting state. to examine functional differentiation of the auditory association area (A2) in prelingually deaf subjects. Methods: six postlingually and six prelingually deaf subjects who had undergone cochlear implant (CI) were involved in the current study. All prelingually deaf subjects underwent CI over 8 years old. The rCBF in A2 was examined during resting and listening to speech sounds using positron emission tomography (PET) and H2(15)O intravenous injection. Twelve normal subjects' rCBFs were also measured as control. Furthermore, three prelingually deaf subjects underwent follow up PET studies in which cortical activities in A2 for listening and lipreading were examined. in the examination of rCBF at rest, rCBFs of prelingually deaf subjects in A2 showed significantly higher than those of either the postlingually deaf subjects or normal subjects. During listening, rCBFs in A2 increased in postlingually deaf subjects and normal subjects, while there was no significant rCBF increase in the prelingually deaf. High rCBF level in A2 at rest observed in prelingually deaf subjects implied a lack of synaptic revision, and it was suggested that the functional differentiation for auditory processing was little in the A2 of prelingually deaf subjects. In the follow up study for three prelingually deaf subjects, activation of A2 was observed during lipreading but not during listening in two cases, who had developed the skill of lipreading while speech recognition was not improved by CI. In contrast, the other case had not used any visual clues in daily communication prior to CI, and the hearing acuity was well improved by CI. This case demonstrated an activity in A2 during listening, while lipreading induced no activation. it is suggested that functional differentiation of A2 should differ according to which of visual and auditory clue is chiefly used during critical periods for speech acquisition. The findings are thought to be important for us to schedule the education and treatment for prelingually deaf children.
    Auris Nasus Larynx 11/2000; 27(4):303-10. · 0.95 Impact Factor
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    ABSTRACT: To ascertain effects of medialization thyroplasty on vocal fold vibration in glottic incompetence dysphonia. Quantitative videostroboscopic glottic measurements and vocal function study were perioperatively undertaken in 20 patients undergoing Isshiki's thyroplasty type I. In digitized images, the glottal area, glottal width, posterior glottal width, and amplitude over an entire glottal cycle were measured and normalized by membranous vocal fold length. The ratio of closed phase to total phase of vibratory cycle was calculated from the data of the glottal area and the glottal width at the middle point of the membranous vocal fold. Well-accepted acoustic, aerodynamic, and perceptual measures analyzed vocal function. Glottal area and glottal width were reduced after surgery. While preoperative closure of glottal area was incomplete in all 20 patients, incomplete closure was obtained in 16 patients after surgery. In these 16 patients, closure of glottal width at the middle point of the membranous vocal fold was complete, whereas a posterior glottal gap remained in 14 patients. Closed phase over one cycle of glottal width waveform and amplitude of vocal fold vibration were increased after surgery. Glottal area, glottal width, posterior glottal width, and closed phase over one cycle of glottal width waveform correlated with vocal function measures. Thyroplasty type I reduces a glottal gap and increases closed phase over one cycle and amplitude of vocal fold vibration, although a posterior glottal gap remains. With the improved glottic vibration, thyroplasty type I provides more efficient phonation in patients with glottic incompetence dysphonia.
    The Laryngoscope 08/2000; 110(7):1086-91. · 1.98 Impact Factor
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    ABSTRACT: To investigate the cortical activities while listening to noise and speech in cochlear implant (CI) users, we compared cerebral blood flow in postlingually deafened CI users with that in normal hearing subjects using positron emission tomography. While noise activation in CI users did not significantly differ from that in normal subjects, hearing speech activated more cortical areas in CI users than in normal subjects. A comparison of speech activation in these two groups revealed higher activation in CI users not only in the temporal cortices but also in Broca’s area and its right hemisphere homologue, the supplementary motor area and the anterior cingulate gyrus. In postlingually deafened subjects, the hearing of speech coded by CI may be accompanied by increased activation of both the temporal and frontal cortices.
    Hearing Research 06/2000; · 2.54 Impact Factor

Publication Stats

555 Citations
69.40 Total Impact Points

Institutions

  • 1990–2007
    • Kyoto University
      • • Graduate School of Medicine / Faculty of Medicine
      • • Department of Otolaryngology
      Kyoto, Kyoto-fu, Japan
  • 1999–2000
    • Nishi-Kobe Medical Center
      Kōbe, Hyōgo, Japan
    • Kobe City Medical Center General Hospital
      Kōbe, Hyōgo, Japan