Tooth detection for each tooth type by application of faster R-CNNs to divided analysis areas of dental panoramic X-ray imagesRadiological Physics and Technology - Tập 15 - Trang 170-176 - 2022
Yuichi Mima, Ryohei Nakayama, Akiyoshi Hizukuri, Kan Murata
This study aimed to propose a computerized method for detecting the tooth region for each tooth type as the initial stage in the development of a computer-aided diagnosis (CAD) scheme for dental panoramic X-ray images. Our database consists of 160 panoramic dental X-ray images obtained from 160 adult patients. To reduce false positives (FPs), the proposed method first extracts a rectangular area i...... hiện toàn bộ
Polarity effect in commercial ionization chambers used in photon beams with small fieldsRadiological Physics and Technology - Tập 2 Số 1 - Trang 97-103 - 2009
Shimono, Tetsunori, Koshida, Kichiro, Nambu, Hidekazu, Matsubara, Kosuke, Takahashi, Hiroshi, Okuda, Hiroshi
Ionization chambers are the instruments of choice for use in photon dosimetry. Ionization chambers together with radiographic films represent the best detectors for measurement of dose distribution for a quality assurance (QA) program in intensity-modulated radiotheraphy (IMRT). The polarity effect was investigated for seven different commercially available ionization chambers. This study concentr...... hiện toàn bộ
Voxel-based morphometry analysis of double inversion-recovery magnetic resonance imaging for detecting microscopic lesions: a simulation studyRadiological Physics and Technology - Tập 12 - Trang 149-155 - 2019
Sato Yusuke, Hayashi Norio, Maruyama Tomoko, Motegi Shunichi, Ujita Koichi, Suto Takayuki, Watanabe Haruyuki, Ogura Toshihiro, Ogura Akio, Tsushima Yoshito
Double inversion-recovery (DIR) imaging has the potential to improve the detection of subcortical lesions through the use of voxel-based morphometry (VBM) analysis. The aim of this study was to clarify the characteristics of detectable lesions by performing a VBM analysis on DIR images of simulated lesions. Twenty healthy volunteers underwent magnetic resonance imaging using a head three-dimension...... hiện toàn bộ
Computed tomography image representation using the Legendre polynomial and spherical harmonics functionsRadiological Physics and Technology - Tập 14 - Trang 113-121 - 2021
Taisei Shimomura, Akihiro Haga
The representation of computed tomography (CT) images using the Legendre polynomial (LPF) and spherical harmonics (SHF) functions was investigated. We selected 100 two-dimensional (2D) CT images of 10 lung cancer patients and 33 three-dimensional (3D) CT images of head and neck cancer patients. The reproducibility of these special functions was evaluated in terms of the normalized cross-correlatio...... hiện toàn bộ
AcknowledgmentRadiological Physics and Technology - Tập 5 - Trang 277-277 - 2012