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Dive into the research topics where Akira Ganaha is active.

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Featured researches published by Akira Ganaha.


Auris Nasus Larynx | 2011

Efficacy of diffusion-weighted magnetic resonance imaging in the diagnosis of middle ear cholesteatoma

Akira Ganaha; Shigeto Outa; Asanori Kyuuna; Sen Matayoshi; Ayano Yonaha; Mika Oyadomari; Tetsuhiro Miyara; Tetsuya Tono; Mikio Suzuki

OBJECTIVE This study evaluated the usefulness of diffusion-weighted magnetic resonance imaging (DWI) in the diagnosis of middle ear cholesteatoma. METHODS We performed DWI on 73 patients suspected of having middle ear cholesteatoma, including 21 revision cases. Magnetic resonance imaging was performed with 1.5T units using diffusion-weighted spin-echo-type echo planar imaging (DWI). RESULTS Of 73 subjects, 59 had cholesteatoma that consisted of 41 primary acquired cholesteatoma, 13 had residual and/or recurrent cholesteatoma, four had congenital cholesteatoma, and one had iatrogenic cholesteatoma. Positive DWI findings were observed in 42 subjects and negative findings in 31 subjects. The sensitivity, specificity, and positive and negative predictive values of DWI for cholesteatoma were 69.4%, 92.8%, 97.5%, and 41.9%, respectively. In the case of 34 patients who were positive for cholesteatoma on both otoscopic and CT examinations, 33 were diagnosed with cholesteatoma. Of the remaining 39 subjects with one or both negative results for cholesteatoma, the sensitivity, specificity, positive predictive value, and negative predictive value of DWI were 57.6%, 92.3%, 93.7%, and 52.1%, respectively. Cholesteatoma mass diameters were less than 5mm in 10 out of 18 subjects with both cholesteatoma and negative DWI findings. Of the 21 subjects who received revision surgery, the sensitivity, specificity, and positive and negative predictive values of DWI for residual or recurrent acquired cholesteatoma were 71.4%, 100%, 100%, and 63.6%, respectively. CONCLUSIONS Since DWI clearly showed high specificity and positive predictive value, it is useful for diagnosing middle ear cholesteatoma, including postoperative recurrent cholesteatoma of 5mm diameter or larger. DWI could sufficiently detect cholesteatoma with one or both negative results on otoscopic and CT examinations, but it was difficult to detect cholesteatoma of less than 5mm diameter using DWI owing to the tiny mass and small volume of debris.


International Journal of Oncology | 2014

Prediction of concurrent chemoradiotherapy outcome in advanced oropharyngeal cancer

Masahiro Hasegawa; Hiroyuki Maeda; Zeyi Deng; Asanori Kiyuna; Akira Ganaha; Yukashi Yamashita; Sen Matayoshi; Shinya Agena; Takafumi Toita; Takayuki Uehara; Mikio Suzuki

The aim of this study was to investigate human papillomavirus (HPV) infection as a predictor of concurrent chemoradiotherapy (CCRT) response and indicator of planned neck dissection (PND) for patients with advanced oropharyngeal squamous cell carcinoma (OPSCC; stage III/IV). Overall, 39 OPSCC patients (32 men, 7 women; median age 61 years, range 39–79 years) were enrolled. The primary lesion and whole neck were irradiated up to 50.4 Gy, and subsequently the primary site and metastatic lymph nodes were boosted with a further 16.2 Gy. Although several chemotherapy regimens were employed, 82.1% of OPSCC patients received the combination of nedaplatin and 5-fluorouracil. HPV-related OPSCC (16 cases) was defined as both HPV DNA-positive status by polymerase chain reaction and p16INK4a overexpression by immunohistochemistry. Patients with N2 and N3 disease received PND 2–3 months after CCRT completion. Compared to non-responders, CCRT responders showed significantly lower nodal stage (N0 to N2b) and HPV-positive status in univariate analysis. Patients with HPV-related OPSCC had longer time to treatment failure (TTF) than those with HPV-unrelated OPSCC (p=0.040). Three-year TTF was 81.3 and 47.8% in the HPV-related and HPV-unrelated groups, respectively. There were also significant differences in disease-free survival (DFS) between the two OPSCC patient groups (p=0.042). Three-year DFS was 93.8 and 66.7% in patients with HPV-related and HPV-unrelated OPSCC, respectively. Multivariate logistic analysis showed a lower risk of TTF event occurrence in HPV-related OPSCC (p=0.041) than in HPV-unrelated OPSCC. Thus, HPV testing in addition to nodal stage was useful for predicting CCRT response, especially in advanced OPSCC. Because patients who received PND showed moderate locoregional control, PND is an effective surgical procedure for controlling neck lesions in patients with advanced HPV-unrelated disease.


American Journal of Rhinology & Allergy | 2016

Squamous cell carcinoma antigen as a diagnostic marker of nasal inverted papilloma.

Yukashi Yamashita; Takayuki Uehara; Masahiro Hasegawa; Zeyi Deng; Sen Matayoshi; Asanori Kiyuna; Shunsuke Kondo; Hiroyuki Maeda; Akira Ganaha; Mikio Suzuki

Background Serum squamous cell carcinoma antigen (SCCA) levels are elevated in sinonasal inverted papilloma (IP). However, the relationship between tumor volume and SCCA level, and the influence of skin or pulmonary diseases in which the SCCA level is high, have not been established. Objective To clarify whether the level of serum SCCA can be used as a diagnostic marker of IP. Methods Serum SCCA level was measured in 30 patients with IP (IP group) and 57 with inflammatory disease (inflammatory group). Results Overall, 83.3% in the IP group showed elevated serum SCCA levels regardless of whether they were new patients or patients with recurrent IP, and SCCA levels rapidly decreased after surgery. Only 5.3% had elevated SCCA levels in the inflammatory group. Before surgery, the IP group had a median preoperative SCCA level of 2.4 ng/mL, whereas the median preoperative SCCA level was 0.9 ng/mL in the inflammatory group. Pre- and postoperative SCCA levels were significantly different in the IP group. With regard to the IP diagnosis in the IP and inflammatory groups based on the SCCA level (ng/mL), sensitivity and specificity were 83.3% and 94.7%, respectively. There was no significant correlation between SCCA elevation and respiratory function, and skin disease in the two groups, except for smoking in the IP group. Preoperative SCCA levels were significantly higher in smokers than in never-smokers in the IP group. Tumor volume was significantly correlated with SCCA level in IP. Multivariable logistic analysis showed that tumor volume was a predictor of preoperative SCCA elevation (p = 0.036; 95% confidence interval, 1.027–2.176). Conclusion Serum SCCA level is a reliable diagnostic marker to distinguish new and recurrent IP from inflammatory disease. Because smokers tended to have higher SCCA levels in IP, a different cutoff level might be needed. Although respiratory dysfunction and skin disease were not related to SCCA level, they should be taken into consideration when evaluating SCCA level.


Journal of Human Genetics | 2015

Identification of two novel mutations in the NOG gene associated with congenital stapes ankylosis and symphalangism

Akira Ganaha; Tadashi Kaname; Yukinori Akazawa; Teruyuki Higa; Ayano Shinjou; Kenji Naritomi; Mikio Suzuki

In this study, we describe three unrelated Japanese patients with hearing loss and symphalangism who were diagnosed with proximal symphalangism (SYM1), atypical multiple synostosis syndrome (atypical SYNS1) and stapes ankylosis with broad thumb and toes (SABTT), respectively, based on the clinical features. Surgical findings in the middle ear were similar among the patients. By next-generation and Sanger sequencing analyses, we identified two novel mutations, c.559C>G (p.P178A) and c.682T>A (p.C228S), in the SYM1 and atypical SYNS1 families, respectively. No pathogenic changes were found in the protein-coding regions, exon–intron boundaries or promoter regions of the NOG, GDF5 or FGF9 genes in the SABTT family. Such negative molecular data suggest there may be further genetic heterogeneity underlying SYNS1, with the involvement of at least one additional gene. Stapedotomy resulted in good hearing in all patients over the long term, indicating no correlation between genotype and surgical outcome. Given the overlap of the clinical features of these syndromes in our patients and the molecular findings, the diagnostic term ‘NOG-related-symphalangism spectrum disorder (NOG-SSD)’ is advocated and an unidentified gene may be responsible for this disorder.


Journal of Voice | 2017

Brain Activity in Patients With Adductor Spasmodic Dysphonia Detected by Functional Magnetic Resonance Imaging

Asanori Kiyuna; Norimoto Kise; Munehisa Hiratsuka; Shunsuke Kondo; Takayuki Uehara; Hiroyuki Maeda; Akira Ganaha; Mikio Suzuki

OBJECTIVES Spasmodic dysphonia (SD) is considered a focal dystonia. However, the detailed pathophysiology of SD remains unclear, despite the detection of abnormal activity in several brain regions. The aim of this study was to clarify the pathophysiological background of SD. STUDY DESIGN This is a case-control study. METHODS Both task-related brain activity measured by functional magnetic resonance imaging by reading the five-digit numbers and resting-state functional connectivity (FC) measured by 150 T2-weighted echo planar images acquired without any task were investigated in 12 patients with adductor SD and in 16 healthy controls. RESULTS The patients with SD showed significantly higher task-related brain activation in the left middle temporal gyrus, left thalamus, bilateral primary motor area, bilateral premotor area, bilateral cerebellum, bilateral somatosensory area, right insula, and right putamen compared with the controls. Region of interest voxel FC analysis revealed many FC changes within the cerebellum-basal ganglia-thalamus-cortex loop in the patients with SD. Of the significant connectivity changes between the patients with SD and the controls, the FC between the left thalamus and the left caudate nucleus was significantly correlated with clinical parameters in SD. CONCLUSION The higher task-related brain activity in the insula and cerebellum was consistent with previous neuroimaging studies, suggesting that these areas are one of the unique characteristics of phonation-induced brain activity in SD. Based on FC analysis and their significant correlations with clinical parameters, the basal ganglia network plays an important role in the pathogenesis of SD.


American Journal of Medical Genetics Part A | 2017

Progressive macrothrombocytopenia and hearing loss in a large family with DIAPH1 related disease

Akira Ganaha; Tadashi Kaname; Ayano Shinjou; Yasutsugu Chinen; Kumiko Yanagi; Teruyuki Higa; Shunsuke Kondo; Mikio Suzuki

In this study, we describe a Japanese family with progressive hearing loss and macrothrombocytopenia. Using next‐generation and Sanger sequencing analyses, we identified a heterozygous variant in exon 27 of the DIAPH1 gene (NM_005219), c.3637C>T, p.R1213X. All patients in the family had sensorineural hearing loss and macrothrombocytopenia. None of the patients exhibited a tendency to bleed. No pathogenic variants were found in the MYH9 gene. Hearing loss began with high‐frequency loss during early childhood and progressed to severe hearing loss involving all frequencies. Analyses of the mean platelet volume and platelet distribution width indicated that the macrothrombocytopenia is progressive in patients with DIAPH1 related disease.There are no reports describing progressive macrothrombocytopenia in patients with pathogenic variants of DIAPH1. Thus, progressive macrothrombocytopenia may be a novel feature of deafness patients with pathogenic variants in DIAPH1.


BMC Medical Genetics | 2013

Pathogenic substitution of IVS15 + 5G > A in SLC26A4 in patients of Okinawa Islands with enlarged vestibular aqueduct syndrome or Pendred syndrome

Akira Ganaha; Tadashi Kaname; Kumiko Yanagi; Kenji Naritomi; Tetsuya Tono; Shin-ichi Usami; Mikio Suzuki

BackgroundPendred syndrome (PS) and nonsyndromic hearing loss associated with enlarged vestibular aqueduct (EVA) are caused by SLC26A4 mutations. The Okinawa Islands are the southwestern-most islands of the Japanese archipelago. And ancestral differences have been reported between people from Okinawa Island and those from the main islands of Japan. To confirm the ethnic variation of the spectrum of SLC26A4 mutations, we investigated the frequencies of SLC26A4 mutations and clinical manifestations of patients with EVA or PS living in the Okinawa Islands.MethodsWe examined 22 patients with EVA or PS from 21 unrelated families in Okinawa Islands. The patient’s clinical history, findings of physical and otoscopic examinations, hearing test, and computed tomography (CT) scan of the temporal bones were recorded. To detect mutations, all 21 exons and the exon–intron junctions of SLC26A4 were sequenced for all subjects. Quantitative reverse-transcription polymerase chain reaction (qRT-PCR) for SLC26A4 and calculations using the comparative CT (2−ΔΔCT) method were used to determine the pathogenicity associated with gene substitutions.ResultsSLC26A4 mutations were identified in 21 of the 22 patients. We found a compound heterozygous mutation for IVS15 + 5G > A/H723R in nine patients (41%), a homozygous substitution of IVS15 + 5G > A in six patients (27%), and homozygous mutation for H723R in five patients (23%). The most prevalent types of SLC26A4 alleles were IVS15 + 5G > A and H723R, which both accounted for 15/22 (68%) of the patients. There were no significant correlations between the types of SLC26A4 mutation and clinical manifestations. Based on qRT-PCR results, expression of SLC26A4 was not identified in patients with the homozygous substitution of IVS15 + 5G > A.ConclusionsThe substitution of IVS15 + 5G > A in SLC26A4 was the most common mutation in uniquely found in patients with PS and EVA in Okinawa Islands. This suggested that the spectrum of SLC26A4 mutation differed from main islands of Japan and other East Asian countries. The substitution of IVS15 + 5G > A leads to a loss of SLC26A expression and results in a phenotype of PS and EVA.


Cochlear Implants International | 2004

Relationship of intraoperative and postoperative electrically evoked stapedius reflex threshold and comfort level in cochlear implant patients

Tatsuhito Owa; Akira Ganaha; Masaharu Ura; Tetsuya Tono

The results shown above suggest that higher rates using the ESPrit 3G do indeed lead to better hearing results than when low-rate strategies are employed. Moreover, patients subjectively reported that high-rate strategies improve speech perception in noisy environments. This benefit from high-rate stimulation has also been found by other researchers working with different implant systems (Kiefer et al., 2000; Büchner et al., 2003; Loizou et al., 2000). However, no increase in performance could be found at high rates on the SPRINT body-worn processor, which has a limited update rate and therefore cannot deliver new information with every stimulus at rates above 760 Hz (Figure 1). These findings are comparable to those reported by Vandali et al. (2000), who also did not find any benefit from higher stimulation rates when using a speech processor with limited update rates.


Oncology Letters | 2018

Detection of human papillomavirus in branchial cleft cysts

Taro Ikegami; Takayuki Uehara; Zeyi Deng; Shunsuke Kondo; Hiroyuki Maeda; Asanori Kiyuna; Shinya Agena; Hitoshi Hirakawa; Yukashi Yamashita; Akira Ganaha; Mikio Suzuki

High-risk human papillomavirus (HPV) DNA has been reported to be present in branchial cleft cysts, but further information is required to clarify the role of HPV infection in branchial cleft cysts. The presence of HPV, the viral load and the physical statuses in samples from six patients with branchial cleft cysts were investigated using the polymerase chain reaction (PCR), quantitative PCR, in situ hybridization (ISH) using HPV DNA probes and p16INK4a immunohistochemical analysis. High-risk type HPV-16 DNA was identified in four of the six branchial cleft cysts analyzed. Of the HPV-positive branchial cleft cysts, three exhibited mixed-type integration of HPV. HPV DNA was distributed among the basal-to-granular layers of the cystic wall in ISH analysis, and p16INK4a was weakly expressed in the nuclei and cytoplasm of the same layers in patients with integration. ISH revealed that one patient with episomal-type infection exhibited HPV DNA in the cyst wall and did not express p16INK4a. Two patients without evidence of HPV infection exhibited weak p16INK4a expression in the superficial cyst-lining cells of branchial cleft cysts. These results indicate that infection with high-risk HPV types may be common in branchial cleft cysts. In addition, p16INK4a is not a reliable surrogate marker for HPV infection in branchial cleft cysts.


Clinical Case Reports | 2018

Mild prominence of the Sylvian fissure in a Bainbridge-Ropers syndrome patient with a novel frameshift variant in ASXL3

Yasutsugu Chinen; Sadao Nakamura; Akira Ganaha; Shin Hayashi; Johji Inazawa; Kumiko Yanagi; Koichi Nakanishi; Tadashi Kaname; Kenji Naritomi

A Japanese boy aged 7 years with Bainbridge‐Ropers syndrome (BRPS) had a prominent domed forehead without metric ridge, mild prominence of the Sylvian fissure with bitemporal hollowing, and a heterozygous de novo novel variant “p.P1010Lfs*14” in ASXL3 gene in addition to typical findings of BRPS.

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Mikio Suzuki

University of the Ryukyus

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Hiroyuki Maeda

University of the Ryukyus

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Sen Matayoshi

University of the Ryukyus

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Shunsuke Kondo

University of the Ryukyus

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Takayuki Uehara

University of the Ryukyus

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Asanori Kiyuna

University of the Ryukyus

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Tetsuya Tono

University of the Ryukyus

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Zeyi Deng

University of the Ryukyus

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Shinya Agena

University of the Ryukyus

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