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Featured researches published by Ryoji Hirai.


Acta Oto-laryngologica | 2006

Facial nerve paralysis caused by middle ear cholesteatoma and effects of surgical intervention

Minoru Ikeda; Hidehisa Nakazato; Keiko Onoda; Ryoji Hirai; Akinori Kida

Conclusions. The clinical and surgical findings of this study indicated advanced cholesteatoma in many patients with facial paralysis. The outcome of facial paralysis was good. Poor outcomes were observed in cases with petrosal cholesteatoma and in those who underwent surgery ≥2 months after the onset of paralysis. Objective. To investigate clinical features of cholesteatoma associated with facial paralysis. Material and methods. Sixteen patients with facial paralysis due to middle ear cholesteatoma were reviewed. After removal of the cholesteatoma lesion, a limited area of the fallopian canal, that in which facial nerve edema or redness was evident, was opened. Incision of the epineural sheath for nerve decompression was not performed. Results. Initial paralysis was incomplete in 11 patients (69%). The onset of paralysis was sudden in 12 patients (75%). Labyrinthine fistulae (n=9; 56%) and bone destruction in the cranial fossa (n=10; 63%) were frequently observed. Six patients (38%) were totally deaf due to labyrinthitis. The outcome of facial paralysis was good in 13 patients (81%). Patients who underwent surgery ≥2 months after the onset of paralysis frequently had a poor outcome. Paralysis was not improved in two cases with petrosal cholesteatoma.


Journal of Voice | 2017

Gardasil Vaccination for Recurrent Laryngeal Papillomatosis in Adult Men: First Report: Changes in HPV Antibody Titer.

Kiyoshi Makiyama; Ryoji Hirai; Hiroumi Matsuzaki

BACKGROUND Patients with human papillomavirus (HPV) DNA-positive recurrent laryngeal papillomatosis commonly have repeated recurrences following surgery. The reason is suspected to be a mechanism by which latent HPV infection in the surrounding healthy mucosa reinfects the surgical site. It may be that production of HPV antibodies in the laryngeal mucosa with Gardasil injection could inhibit postoperative recurrence. STUDY DESIGN This is a case series study. PURPOSE The purpose of this study was to examine whether Gardasil injection effectively inhibits recurrence. However, as a first report, we describe the antibody titers before and after vaccination. METHODS Gardasil was injected in 12 men (aged 32-74 years; mean age 47.9 years) with HPV-positive laryngeal papillomatosis. Serum antibody titers of HPV-6, -11, -16, and -18 were measured by a competitive Luminex-based immunoassay before the vaccination and 7 months after the start of the vaccination. RESULTS Each of the antibody titers was very low before vaccination, and they rose in all patients after the vaccination. CONCLUSIONS This finding demonstrates that antibody titers increase with Gardasil injection in post-adolescent males.


Annals of Otology, Rhinology, and Laryngology | 2012

Patients with phantogeusia show increased expression of T2R taste receptor genes in their tongues.

Ryoji Hirai; Kyoichi Takao; Keiko Onoda; Shinichiro Kokubun; Minoru Ikeda

Objectives: The taste receptor gene family T2R has been implicated in the sensation of bitter taste. Phantogeusia is a spontaneous abnormal taste with no external stimulus. We analyzed the expression of T2R taste receptor genes in the tongues of patients with phantogeusia to assess their role in the pathogenesis of phantogeusia. Methods: We obtained specimens from 43 patients with phantogeusia and 24 normal volunteers by scraping the foliate papillae and examined these specimens for the expression of 10 T2R taste receptor genes using reverse transcription–polymerase chain reaction and electrophoresis. Results: The expression rate (subjects with detectable expression) of the 10 taste receptor genes in the healthy subjects ranged from 16.7% to 100%; 3 receptor genes were found in 50% or fewer of these subjects. In the patients with phantogeusia, the expression rate was increased significantly compared to that in the healthy control subjects for 3 of the 10 receptor genes examined. Conclusions: Our results show that the expression rate of some of the T2R taste receptor genes was increased significantly in patients with phantogeusia. These results suggest that increased expression of taste receptor genes is involved in the pathogenesis of phantogeusia; this finding may contribute to elucidation of the mechanism of this disorder.


Journal of Voice | 2013

Assessment of human papilloma virus infection in adult laryngeal papilloma using a screening test.

Kiyoshi Makiyama; Ryoji Hirai; Hiroumi Matsuzaki; Minoru Ikeda

OBJECTIVES Human papilloma virus (HPV) infection is involved in both juvenile and adult laryngeal papilloma. We wished to determine which types of adult laryngeal papilloma were clinically related to HPV infection. We hypothesized that multiple-site and recurrent papillomas would have a strong relationship to HPV and conducted the present study to test this hypothesis. METHODS Thirteen male patients with adult laryngeal papilloma who underwent resection of papilloma between August 2006 and September 2009 were studied. We examined the relationships between whether the tumor was solitary or multiple, presence or absence of recurrence after surgery, and HPV infection. High-risk HPV types (HPV-DNA types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, 59, and 68) and low-risk HPV types (6, 11, 42, 43, and 44) were tested by a liquid-phase hybridization method. In addition, HPV typing was performed for patients positive for low-risk HPV types. Twenty patients with laryngeal carcinoma or laryngeal leukoplakia were enrolled as the control group. RESULTS In the laryngeal papilloma group, all patients tested were negative for high-risk HPV and 69.2% were positive for low-risk HPV. Typing performed for seven of the patients who tested positive for low-risk HPV showed that one patient was positive for HPV-11, whereas the remaining six patients were positive for HPV-6. All patients with recurrent laryngeal papillomatosis (RLP) were positive for low-risk HPV. All patients who were positive for low-risk HPV had RLP. Tumor samples from repeat operations were positive for low-risk HPV in all patients tested. HPV was not detected in the control group. CONCLUSIONS The relationship between RLP and low-risk HPV was strong, with all cases that were positive for low-risk HPV showing recurrence. Tumor tissue resected at the time of repeat surgery was positive for low-risk HPV in all cases tested.


Laryngoscope | 2011

Patients with hypogeusia show changes in expression of T2R taste receptor genes in their tongues

Keiko Onoda; Ryoji Hirai; Kyoichi Takao; Shinichiro Kokubun; Minoru Ikeda

Taste receptor genes associated with bitterness belong to the T2R gene family. In this study, we compared the expression of genes of the T2R family in the tongues of patients with hypogeusia to those in healthy subjects and examined the possibility that T2R genes are involved in the pathogenesis of hypogeusia.


Laryngoscope | 2015

Phonatory aerodynamics in connected speech

Jackie Gartner-Schmidt; Ryoji Hirai; Christina Dastolfo; Clark A. Rosen; Lan Yu; Amanda I. Gillespie

1) Present phonatory aerodynamic data for healthy controls (HCs) in connected speech; 2) contrast these findings between HCs and patients with nontreated unilateral vocal fold paralysis (UVFP); 3) present pre‐ and post‐vocal fold augmentation outcomes for patients with UVFP; 4) contrast data from patients with post‐operative laryngeal augmentation to HCs.


European Archives of Oto-rhino-laryngology | 2012

Pharyngeal squamous cell papilloma in adult Japanese: comparison with laryngeal papilloma in clinical manifestations and HPV infection

Ryoji Hirai; Kiyoshi Makiyama; Yusho Higuti; Atsuo Ikeda; Masatoshi Miura; Hisashi Hasegawa; Noriko Kinukawa; Minoru Ikeda

A number of reports have investigated the relationship between laryngeal papilloma and human papilloma virus (HPV) infection. On the other hand, it is unclear whether the HPV infection is involved in the occurrence of pharyngeal papilloma. We hypothesized that HPV infection was involved in the occurrence of pharyngeal papilloma similarly to laryngeal papilloma. To verify this hypothesis, we investigated the presence of HPV infection. Furthermore, clinical manifestations of pharyngeal papilloma, which had rarely been reported, were discussed. A male-to-female ratio, solitary or multiple occurrences, and koilocytosis were examined in cases with pharyngeal papilloma. HPV DNA was examined with unfixed surgically resected specimens of pharyngeal papilloma. A screening test by the liquid-phase hybridization method was carried out for the HPV high-risk group (16, 18, 31, 33, 35, 39, 45, 51, 56, 58, 59, and 68) and HPV low-risk group (6, 11, 42, 43, 44). As a control, 15 cases with laryngeal papilloma for which the same screening test was carried out were employed. Pharyngeal papilloma occurred as a solitary lesion more often, whereas laryngeal papilloma occurred as multiple tumors more frequently. The HPV infection rate was 0% in pharyngeal papilloma cases, which was in stark contrast with 66.7% in the HPV low-risk group in laryngeal papilloma cases. Pharyngeal papilloma occurred as a solitary lesion in females more frequently. Contrary to our hypothesis, the involvement of HPV infection was unlikely in the occurrence of pharyngeal papilloma.


Otolaryngology-Head and Neck Surgery | 2007

Phonatory function of the elderly determined by intensity-loading test: A comparison with the young

Kiyoshi Makiyama; Hidetaka Yoshihashi; Ryoji Hirai; Hitomi Kodama; Yukimi Asano

Objective The goal was to test the hypothesis that the elderly have diminished laryngeal regulation capability, so we investigated phonatory function in the elderly and young using a sound pressure-loading test. Study Design and Setting In 36 healthy men (17 in their 20s, 19 in their 70s) and 45 healthy women (22 in their 20s, 23 in their 70s), fundamental frequency, sound pressure level, mean flow rate (MFR), and expiratory lung pressure (EP) were determined from phonatory function testing. Subjects phonated at a comfortable level and at high intensity, without changing vocal pitch. Results MFR, EP, and airway resistance increased with high-intensity phonation in the young; however, only MFR and EP increased in the elderly. Conclusions The findings supported our hypothesis: with high-intensity phonation, the elderly undergo unchanged laryngeal regulation but a greater degree of expiratory regulation. Significance The elderly are likely to become tired due to the effort required for phonation.


Journal of Voice | 2017

Gardasil Vaccination for Recurrent Laryngeal Papillomatosis in Adult Men Second Report: Negative Conversion of HPV in Laryngeal Secretions

Ryoji Hirai; Kiyoshi Makiyama; Hiroumi Matsuzaki; Takeshi Oshima

BACKGROUND In our first report on antibody levels in middle-aged and older men with recurrent laryngeal papillomatosis (RLP), we reported increases in human papillomavirus (HPV) antibody levels similar to those seen in adult women and young men. We posited that HPV antibodies produced in laryngeal mucus by Gardasil would prevent postoperative reinfection in patients with RLP. STUDY DESIGN This is a case series study. PURPOSE The purpose of this study was to examine whether Gardasil injection effectively inhibits recurrence of RLP. Specifically, in this second report, whether HPV antibodies produced in laryngeal secretions by Gardasil are capable of causing negative conversion of HPV-DNA (deoxyribonucleic acid) in laryngeal mucosa was investigated. METHODS A total of 11 patients for whom antibodies were measured in the first report were studied. Before vaccination and after 1 year Post-vaccination, HPV screening tests were performed on laryngeal secretions, and whether HPV-DNA negative conversion had occurred was evaluated. At the time of collection of laryngeal secretions, the presence or absence of laryngeal papillomas was examined. RESULTS Before vaccination, all patients were HPV low-risk positive on laryngeal secretion screening tests. After vaccination, three patients were positive. Laryngeal papillomas remained in five patients. CONCLUSIONS The HPV-DNA test showed negative conversion in eight of 11 (72.7%) patients after vaccination. Residual laryngeal papillomas were found in five of 11 (45.5%) patients. The serum HPV antibody titer did not differ significantly between the group in which laryngeal secretions showed HPV negative conversion and the group in which conversion did not occur. The serum antibody titer did not differ significantly as a function of whether there were residual tumors.


Journal of Laryngology and Otology | 2011

A case of middle-ear cavernous lymphangioma with facial palsy.

Ryoji Hirai; Minoru Ikeda; Hiroyuki Kishi; Yasuyuki Nomura; Shuntaro Shigihara

OBJECTIVE Only a few benign tumours of the middle ear have been reported to lead to the development of facial palsy. Here, we describe a patient with middle-ear cavernous lymphangioma and facial palsy. STUDY DESIGN Single case study. PATIENT A 61-year-old man presented with left-sided hearing impairment and incomplete left facial palsy. A tumour was confirmed to be occupying the epi- to mesotympanum and to be joined to the facial nerve. The tumour was removed along with facial nerve tissue, which was resected at its horizontal portion, and the remaining facial nerve was fixed by end-to-end anastomosis. Complete facial paralysis occurred after the operation, but the patients House-Brackmann grade gradually improved to grade III. Post-operative histopathological examination revealed infiltration of the lymphangioma into the facial nerve tissue, together with mild neural atrophy of the facial nerve. CONCLUSION These findings suggested that tumour invasion was the cause of facial palsy in this patient.

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