Yutaka Yamamoto

Prof. Yutaka Yamamoto

orcid

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 June 2019 in Otology & Neurotology
Verified
Journal Article
Closed access
AJAdrian James
Adrian James
TTTetsuya Tono
Tetsuya Tono
MCMichael Saul Cohen
Michael Saul Cohen
AIArunachalam Iyer
Arunachalam Iyer
LCLynn Cooke
Lynn Cooke
MYMatthew Yung
Matthew Yung
Objective: Assessment of validity of the Japanese Otological Society and the European Academy of Otology and Neurotology (EAONO–JOS) cholesteatoma staging system (EJS) through international collaboration to investigate: (a) feasibility of retrospectively staging previously acquired data, (b) strengths and weaknesses of the staging system. Method: Nine centers with prospective cholesteatoma databases were recruited. Cases were allocated to EJS Stage at each center using details from time of initial surgery. An independent rater also staged the cases and noted any discrepancies. At one center results from database staging were compared with staging based on contemporaneous operative records. Inter and intrarater reliabilities were calculated, and recidivism rates calculated according to Stage. Results: Of 1482 cases of cholesteatoma, 320 (22%) were Stage 1, 977 (67%) Stage 2, 153 (11%) Stage 3 and 4 (0.3%) Stage 4. No database contained details of all parameters required for accurate staging. Staging discrepancies occurred in >10% cases but inter and intrarater reliability of staging were high (Kappa 0.8; 95% confidence interval between 0.7–0.9). At 5 years, 11% had residual and 8% had recurrent cholesteatoma: rates increased with Stage but generally not significantly (Kaplan–Meier Log Rank analysis). Conclusion: The EJS Staging system provides an internationally agreed standard for collecting data to classify cholesteatoma severity. Although data can be applied retrospectively with reasonable reliability, prospective data collection would prevent inaccuracies that arise from missing data fields. To enhance validity of the EJS system, we propose clearer definitions of some categories. Refinements to definitions of stage may improve prognostic utility of the EJS but should be made using evidence powered by large-scale collaboration.

1 July 1999 in Breast Cancer
Verified
Journal Article
Closed access
PDF file
YMYoshihiko Murayama
Yoshihiko Murayama
YYYutaka Yamamoto
Yutaka Yamamoto
NSNaoki Shimojima
Naoki Shimojima
TTTetsuya Takahara
Tetsuya Takahara
KKKaichiro Kikuchi
Kaichiro Kikuchi
YKYasuko Kondo
Yasuko Kondo


1 June 2019 in Auris Nasus Larynx
Verified
Journal Article
Closed access
YMYuka Morita
Yuka Morita
TTTetsuya Tono
Tetsuya Tono
MSMasafumi Sakagami
Masafumi Sakagami
YYYutaka Yamamoto
Yutaka Yamamoto
KMKeiji Matsuda
Keiji Matsuda
HKHiromi Kojima
Hiromi Kojima

20 March 2024 in Journal of Clinical Medicine
Verified
Journal Article
Open access
PDF file
KTKeisuke Tsuchida
Keisuke Tsuchida
MTMasahiro Takahashi
Masahiro Takahashi
TNTakara Nakazawa
Takara Nakazawa
SKSho Kurihara
Sho Kurihara
KYKazuhisa Yamamoto
Kazuhisa Yamamoto
HKHiromi Kojima
Hiromi Kojima
Background: The indications for transcanal endoscopic ear surgery (TEES) for middle ear cholesteatoma have expanded for cases involving mastoid extension. However, TEES is not indicated for all cases with mastoid extension. In addition, predicting the extent of external auditory canal (EAC) removal needed for cholesteatoma resection is not always easy. The purpose of this study was to use augmented reality (AR) to project the lesion onto an intraoperative endoscopic image to predict EAC removal requirements and select an appropriate surgical approach. Methods: In this study, patients showing mastoid extension were operated on using a navigation system with an AR function (Stryker). Results: The results showed that some cases with lesions slightly extending into the antrum required extensive resection of the EAC, while cases with lesions extending throughout the antrum required smaller resection of the EAC, indicating TEES. Conclusions: By predicting the extent of the needed EAC removal, it is possible to determine whether TEES (a retrograde approach) or canal wall-up mastoidectomy, which preserves as much of the EAC as possible, should be performed. We believe that our findings will contribute to the success of middle ear surgeries and the implementation of robotic surgery in the future.

8 April 2016 in Acta Oto-Laryngologica
Verified
Journal Article
Closed access
PDF file
Manabu KomoriManabu Komori
Manabu Komori
YYYutaka Yamamoto
Yutaka Yamamoto
YYYuichiro Yaguchi
Yuichiro Yaguchi
TITetsuo Ikezono
Tetsuo Ikezono
HKHiromi Kojima
Hiromi Kojima
Conclusion: Approximately 50% of patients with sPLF based on the clinical diagnosis criteria were definitively diagnosed with CTP-positive sPLF. These results suggest that early surgery within 7 days of the disease onset contributes to improvements in the therapeutic response of hearing loss. Objectives/Hypothesis: Idiopathic spontaneous perilymph fistula (sPLF) cannot be diagnosed reliably. It is speculated that this condition occurs in patients with vertigo-accompanied acute sensorineural hearing loss that progresses rapidly in spite of steroid therapy. This study herein evaluated cochlin-tomoprotein (CTP) test results in patients with sPLF who underwent exploratory tympanotomy and considered surgical outcomes with true sPLF. Study design: Retrospective study. Methods: Twenty-three patients diagnosed with sPLF based on the clinical diagnosis criteria who underwent exploratory tympanotomy were included. Results: CTP test results were positive in 11 cases. In CTP-positive cases, the mean hearing level was 66.5 dB pre-operatively and 42.3 dB post-operatively. The hearing level post-operatively completely recovered in four cases, markedly recovered in three cases, slightly recovered in one case and showed no response in three cases. Hearing level improvements were significantly better in CTP-positive patients who underwent surgery within 7 days of the disease onset than in those treated 8 or more days after the disease onset.