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Dive into the research topics where Hironori Akiyama is active.

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Featured researches published by Hironori Akiyama.


Journal of Radiation Research | 2012

Dose reduction trial from 60 Gy in 10 fractions to 54 Gy in 9 fractions schedule in high-dose-rate interstitial brachytherapy for early oral tongue cancer

Hironori Akiyama; Ken Yoshida; Kimishige Shimizutani; Hideya Yamazaki; Masahiko Koizumi; Yasuo Yoshioka; Naoya Kakimoto; Shumei Murakami; Souhei Furukawa; Kazuhiko Ogawa

To compare the effects of 60 Gy/10 fractions (twice a day) with those of 54 Gy/9 fractions in high-dose-rate interstitial brachytherapy (HDR-ISBT) for early tongue cancer, we performed a matched-pair analysis of patients with early tongue cancer (T1-2N0M0), who were treated with 60 or 54 Gy of radiation between 1996 and 2004. Seventeen patients treated with 54 Gy and 34 matched-pair patients treated with 60 Gy were extracted and analyzed. Local recurrence occurred in two patients in the 54-Gy arm and five patients in the 60-Gy arm. The 2-year local control rates were 88% for both the 54-Gy arm and 60-Gy arm (not significant). The 2-year overall survival rates were 88% in the 60-Gy arm and 82% in the 54-Gy arm. Two-year actuarial complication-free rates were 91% in the 60-Gy arm and 83% in the 54-Gy arm (not significant), respectively. There was no significant association between the total dose and local control rate and late complications. The outcome of 54 Gy/ 9 fractions was similar to that of 60 Gy/ 10 fractions in patients with early tongue cancer.


Oral Surgery Oral Medicine Oral Pathology Oral Radiology and Endodontology | 2011

A case of synovial chondromatosis of the temporomandibular joint followed for 17 years.

Yui Mori; Kenji Kakudo; Motohiro Gotoh; Hirohito Kubo; Hironori Akiyama; Yoritaka Yotsui; Kimishige Shimizutani

The patient was a 52-year-old woman who visited our hospital for the chief complaint of a strange sensation in the left temporomandibular joint region on February 22, 1992. On the first examination, crepitus was heard, but no disturbance of mouth opening was noted. On panoramic radiography, radiopaque bodies were present in the left temporomandibular joint region, diagnosed as synovial chondromatosis. Course observation without active treatment was selected. Calcified bodies were noted on the lateral side directly below the left temporomandibular articular tubercle on the first computed tomography image performed in December 1998. Reportedly, this lesion grows slowly, but the lesions started to enlarge at a specific time point during the 17-year follow-up in this patient, showing the necessity of long-term follow-up by imaging even though no quality-of-life reduction or subjective symptom is observed.


Journal of Gynecologic Oncology | 2015

Role of vaginal pallor reaction in predicting late vaginal stenosis after high-dose-rate brachytherapy in treatment-naive patients with cervical cancer

Ken Yoshida; Hideya Yamazaki; Satoaki Nakamura; Koji Masui; Tadayuki Kotsuma; Hironori Akiyama; Eiichi Tanaka; Nobuhiko Yoshikawa; Yasuo Uesugi; T. Shimbo; Yoshifumi Narumi; Yasuo Yoshioka

Objective To assess actual rates of late vaginal stenosis and identify predisposing factors for complications among patients with previously untreated cervical cancer following high-dose-rate brachytherapy. Methods We performed longitudinal analyses of 57 patients using the modified Dische score at 6, 12, 18, 24, 36, and 60 months after treatment, which consisted of 15 interstitial brachytherapys and 42 conventional intracavitary brachytherapys, with a median follow-up time of 36 months (range, 6 to 144 months). Results More than half of the patients developed grade 1 (mild) vaginal stenosis within the first year of follow-up, and grade 2 (97.5%, moderate) to grade 3 (severe) stenosis gradually increased with time. Actual stenosis rates for grade 1, 2, and 3 were 97.5% (95% confidence interval [CI], 92.7 to 97.5), 60.7% (95% CI, 42.2 to 79.3), and 7.4% (95% CI, 0 to 18.4) at 3 years after treatment. Pallor reaction grade 2-3 at 6 months was only a statistically significant predisposing factor for grade 2-3 late vaginal stenosis 3 years or later with a hazard ratio of 3.48 (95% CI, 1.32 to 9.19; p=0.018) by a multivariate Cox proportional hazard model. Patients with grade 0-1 pallor reaction at 6 months showed a grade ≥2 vaginal stenosis rate of 53%, whereas the grade 2-3 pallor reaction group achieved a grade ≥2 vaginal stenosis rate at 3 years at 100% (p=0.001). Conclusion High-dose-rate brachytherapy was associated with high incidence of late vaginal stenosis. Pallor reaction grade 2-3 at 6 months was predictive of late grade 2-3 vaginal stenosis at 3 years after treatment. These findings should prove helpful for patient counseling and preventive intervention.


Journal of Radiation Research | 2014

Three-dimensional image-based high-dose-rate interstitial brachytherapy for mobile tongue cancer

Ken Yoshida; Tadashi Takenaka; Hironori Akiyama; Hideya Yamazaki; Mineo Yoshida; Koji Masui; Tadayuki Kotsuma; Sungjae Baek; Yasuo Uesugi; T. Shimbo; Nobuhiko Yoshikawa; Takumi Arika; Yukihiro Koretsune; Yasuo Yoshioka; Yoshifumi Narumi; Eiichi Tanaka

To investigate the influence of a 3D image-based treatment-planning method for high-dose-rate interstitial brachytherapy (HDR-ISBT) for mobile tongue cancer, we analyzed dose–volume histogram results for the clinical target volume (CTV) and the mandible. Between October 2010 and November 2011, one and four patients having T2 and T3 tumors, respectively, were treated with HDR-ISBT. Multiplane implantation using 9–15 treatment applicators was performed. Lugols iodine staining, metal markers, ultrasonography, and magnetic resonance imaging were used to identify the contours of the gross tumor volume (defined as the CTV). The results of the image-based treatment plan were compared with those of the conventional simulated plan on the basis of a reference point 5 mm from the applicator position. The mean D90(CTV) and V100(CTV) were 112% of the prescribed dose (PD) and 98.1%PD, respectively, for the image-based plan, and 113%PD and 97.2%PD, respectively, for the conventional plan. The median CTVref/Vref was 0.23 for the image-based plan and 0.16 for the conventional plan (P = 0.01). The mean D0.1 cm3 (mandible), D1 cm3 (mandible), and D2 cm3 (mandible) were 80.1%PD, 62.5%PD, and 55.7%PD, respectively, for the image-based plan, and 109.1%PD (P = 0.02), 82.4%PD (P = 0.005), and 74%PD (P = 0.004), respectively, for the conventional plan). Image-based treatment planning may achieve high-conformity radiotherapy for the CTV and decrease irradiated doses to the mandible.


Oncology Letters | 2017

Calcifying cystic odontogenic tumor accompanied by a dentigerous cyst: A case report

Shoko Gamoh; Hironori Akiyama; Chisato Furukawa; Yuki Matsushima; Tomio Iseki; Masahiro Wato; Akio Tanaka; Shosuke Morita; Kimishige Shimizutani

A calcifying cystic odontogenic tumor (CCOT) is a proliferation of odontogenic epithelium and scattered nests of ghost cells and calcifications that may form the lining of a cyst, or present as a solid mass. It was previously described by Gorlin et al in 1962 as a calcifying odontogenic cyst. Dentigerous cysts are developmental odontogenic jaw cysts, commonly manifesting in the second and third decades of life. The present study reports an asymptomatic case in a 13-year-old boy who was referred to the outpatient clinic of the Osaka Dental University Hospital (Osaka, Japan) for additional investigation of an area of radiolucency in the lower right jaw. X-ray demonstrated a unilocular, well-circumscribed, radiolucent lesion in the mandible, which measured 30×20 mm, with radiopaque structures within it. Enucleation of the lesion with tooth extraction was performed, which histopathologically revealed features of a CCOT and a cyst. To the best of our knowledge, the occurrence of such a lesion has not been previously identified. The present study examined the significance of the case with a brief review of the literature.


Journal of Contemporary Brachytherapy | 2017

Edema worsens target coverage in high-dose-rate interstitial brachytherapy of mobile tongue cancer: a report of two cases.

Ken Yoshida; Hideya Yamazaki; Tadayuki Kotsuma; Hironori Akiyama; Tadashi Takenaka; Koji Masui; Yasuo Yoshioka; Yasuo Uesugi; T. Shimbo; Nobuhiko Yoshikawa; Hiroto Yoshioka; Takumi Arika; Eiichi Tanaka; Yoshifumi Narumi

Purpose We report our study on two patients to highlight the risk of underdosage of the clinical target volume (CTV) due to edema during high-dose-rate interstitial brachytherapy (HDR-ISBT) of mobile tongue cancer. Material and methods To treat the lateral side of the CTV, flexible applicator tubes were implanted on the mouth floor. Two-dimensional planning was performed using X-ray images for Case 1, and three-dimensional (3D) planning was performed using computed tomography (CT) for Case 2. Prescribed doses for both cases were 54 Gy in nine fractions. Case reports Case 1 was treated for cancer of the right lateral border of the tongue in 2005. Tongue edema occurred after implantation, and part of the lateral border of the tongue protruded between the applicator tubes. Acute mucosal reaction abated in the protruded area earlier than in the other parts of the CTV. In this case, the tumor recurred in this area 5 months after the treatment. Case 2 was treated for cancer of the left lateral border of the tongue. Because tongue edema occurred in this case also, plastic splints were inserted between the applicator tubes to push the edematous region into the irradiated area. The mucosal surface of the CTV was covered by the 70% isodose, and 100% isodose line for before and after splint insertion. Local control of the tumor was achieved 4 years after treatment. Discussion and conclusions To ensure sufficient target coverage, 3D image-based planning using CT should be performed, followed by re-planning using repeated CT as needed. Also, the development of devices to prevent protrusion of the edematous tissue outside the target area will help to ensure the full dosing of CTV.


Oral Radiology | 2016

Extraordinarily favorable recovery from unilateral condylar fracture in a 4-year-old girl

Shoko Gamoh; Hironori Akiyama; Koji Yamada; Kaname Tsuji; Tomio Iseki; Shosuke Morita; Kimishige Shimizutani

IntroductionManagement of condylar fractures in children is especially important. If not properly treated, these fractures may lead to serious problems, such as ankylosis of the temporomandibular joint. This article describes an extraordinarily favorable recovery after conservative treatment of a unilateral condylar fracture in a 4-year-old girl.Case presentationA 4-year-old Japanese girl was referred to our institution with a right mandibular condylar fracture caused by a fall. In this article, we report the 2-year follow-up of this case by clinical and radiological evaluations after conservative treatment, highlighting the strategy used.ConclusionsThe outcomes throughout the 2-year follow-up and the remodeling process of the condyle observed on panoramic radiographs and computed tomographic images proved the suitability of the conservative treatment.


Oral Surgery, Oral Medicine, Oral Pathology, and Oral Radiology | 2014

Fibrosarcoma of the temporomandibular joint area: benefits of magnetic resonance imaging and computed tomography

Shoko Gamoh; Yukako Nakashima; Hironori Akiyama; Kaname Tsuji; Koji Yamada; Motoyuki Suzuki; Shosuke Morita; Kimishige Shimizutani

Here, we report a case of primary fibrosarcoma in the mandible of a 33-year-old woman with symptoms and radiologic signs mimicking temporomandibular disorder. We also present a literature review of fibrosarcomas in the jaw. CASE REPORT A 33-year-old woman presented with a 1-year history of trismus associated with a clicking noise in the left temporomandibular joint (TMJ). Her chin shifted to the right side when she opened her mouth (Figure 1). Panoramic radiographs (Figure 2, A, B) and magnetic resonance imaging (MRI) scans (Figure 3, A-H) of the TMJ regions showed signs of temporomandibular disorder (TMD), so conventional treatment for TMD was prescribed, including occlusal splints, mouth-opening exercises, and a muscle relaxant for 6 months. When the MRI scout images were analyzed retrospectively, the findings of 2 of 5 scout images were suggestive of tumor (see Figure 3, A, E). The patient was referred again 6 months after the initial visit for investigation of insomnia caused by spontaneous pain in the left TMJ area. She also had paralysis of the lower lip and left chin. She had herpes labialis and gastroenteritis caused by stress. Given the suspicion of malignancy, both MRI and computed tomography (CT) were performed. MRI showed a round, inhomogeneous mass in the pterygomandibular portion of the masticator space, which caused minimal medial narrowing of the left parapharyngeal space (Figure 4, A, B). CT found significant bony erosion of the inner cortex of the left ramus of the mandible (Figure 5). The patient was referred to another hospital for further management because the tumor grew toward the pharyngeal arches. An incisional biopsy was subsequently performed, and the initial diagnosis was a sarcoma based on the histopathologic examination of the biopsy. A definitive histologic diagnosis was reached by exclusion. The tumor was diagnosed as a grade 3 (poorly differentiated) fibrosarcoma using the FNCLCC (Federation Nationale des Centres de Lutte Contre le Cancer) grading system. Histopathologic examination found that the tumor contained spindle cells arranged in compact fascicles that were intersected by various amounts of delicate thin to dense keloid-like collagen. Cell bundles were arranged at acute angles to each other, whereas the presence of fascicles was subtler in other areas. A prominent storiform pattern was not seen (Figure 6). The fibrosarcoma was resected followed by postoperative radiotherapy and chemotherapy. The tumor was removed, along with the left ramus of the mandible, a portion of the left maxilla, a deep part of the parotid gland, and lymph nodes located superior to the omohyoid muscle. The cheek mucosa was reconstructed using a free anterolateral thigh flap (Figure 7). The patient recovered and got married afterward; however, lung metastasis with Fig. 1. Facial photograph. The patient’s chin shifted to the right side when she opened her mouth.


Oral Radiology | 2018

Gas gangrene in the deep spaces of the head and neck visualized on computed tomography images

Shoko Gamoh; Kaname Tsuji; Hugo Maruyama; Hiroyuki Hamada; Hironori Akiyama; Isumi Toda; Pao-Li Wang; Shosuke Morita; Kimishige Shimizutani

Cellulitis accompanied by gas gangrene is a rapidly-spreading and potentially fatal infection. Here, we present a case of gas gangrene in the deep spaces of the head and neck in an elderly woman, diagnosed by computed tomography (CT). An 86-year-old woman with Alzheimer’s disease, hypertension, hyperlipidemia, and osteoporosis was referred to our institute by her local dentist. The patient exhibited trismus caused by severe swelling in the left submandibular area. CT images of the head and neck area showed swelling of the cervical tissue with air in the parapharyngeal and masticator spaces. She was treated with antibiotics, followed by drainage. Although the therapy was continued, the patient died from a cardiac complication on hospital day 42. Our case highlights the usefulness of CT for diagnosing gas gangrene in the deep spaces of the head and neck in a woman with Alzheimer’s disease.


Oral Radiology | 2018

Non-contrast computed tomography and magnetic resonance imaging features of mucoepidermoid carcinoma in the salivary glands

Shoko Gamoh; Hironori Akiyama; Kaname Tsuji; Tetsuro Nakazawa; Shosuke Morita; Akio Tanaka; Kimishige Shimizutani

BackgroundUse of contrast-enhanced cross-sectional imaging is considered standard practice for investigating mucoepidermoid carcinoma (MEC) in the salivary glands. The purpose of this study was to present the common features of MEC on computed tomography (CT) and magnetic resonance imaging (MRI) without contrast enhancements, and to investigate the possibility of discriminating between MEC and pleomorphic adenoma based on the features observed on both modalities.MethodsTwenty cases of biopsy-confirmed MEC originating in the salivary glands were reviewed and characterized by two oral and maxillofacial radiologists with regard to the following aspects: detectability, margin, border, encapsulation, content, contrast between lesion and masticator muscle, and bone changes.ResultsNinety percent of bone changes caused by MEC were detected by CT and sixty-nine percent of tumor existences were detected by MRI. The lesion border could provide a clue to distinguish MEC from pleomorphic adenoma.ConclusionsObservation of MEC features was possible by both CT and MRI. Among the features, the lesion border could be a clue to distinguish MEC from pleomorphic adenoma.

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Shoko Gamoh

Osaka Dental University

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Hideya Yamazaki

Kyoto Prefectural University of Medicine

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Koji Masui

Kyoto Prefectural University of Medicine

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Kaname Tsuji

Osaka Dental University

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