Journal of X-Ray Science and Technology - Volume Pre-press, issue Pre-press

Authors: Wei, Jiangping | Lei, Pinggui | Yang, Hong | Fan, Bing | Qiu, Yingying | Zeng, Bingliang | Yu, Peng | Lv, Jian | Jian, Yinchao | Wan, Chengfeng

Article Type: Research Article

Abstract: Purpose: To analyze clinical and thin-section computed tomographic (CT) data from the patients with coronavirus disease (COVID-19) to predict the development of pulmonary fibrosis after hospital discharge. Materials and methods:: Fifty-nine patients (31 males and 28 females ranging from 25 to 70 years old) with confirmed COVID-19 infection performed follow-up thin-section thorax CT. After 31.5±7.9 days (range, 24 to 39 days) of hospital admission, the results of CT were analyzed for parenchymal abnormality (ground-glass opacification, interstitial thickening, and consolidation) and evidence of fibrosis (parenchymal band, traction bronchiectasis, and irregular interfaces). Patients were analyzed based on the evidence of …fibrosis and divided into two groups namely, groups A and B (with and without CT evidence of fibrosis), respectively. Patient demographics, length of stay (LOS), rate of intensive care unit (ICU) admission, peak C-reactive protein level, and CT score were compared between the two groups. Results:: Among the 59 patients, 89.8% (53/59) had a typical transition from early phase to advanced phase and advanced phase to dissipating phase. Also, 39% (23/59) patients developed fibrosis (group A), whereas 61% (36/59) patients did not show definite fibrosis (group B). Patients in group A were older (mean age, 45.4±16.9 vs. 33.8±10.2 years) (P  = 0.001), with longer LOS (19.1±5.2 vs. 15.0±2.5 days) (P  = 0.001), higher rate of ICU admission (21.7% (5/23) vs. 5.6% (2/36)) (P  = 0.061), higher peak C-reactive protein level (30.7±26.4 vs. 18.1±17.9 mg/L) (P  = 0.041), and higher maximal CT score (5.2±4.3 vs. 4.0±2.2) (P  = 0.06) than those in group B. Conclusions:: Pulmonary fibrosis may develop early in patients with COVID-19 after hospital discharge. Older patients with severe illness during treatment were more prone to develop fibrosis according to thin-section CT results. Show more

Keywords: COVID-19, severe acute respiratory syndrome, coronavirus, tomography, X-ray computed

DOI: 10.3233/XST-200685

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-7, 2020

Authors: Wang, Xisheng | Zhang, Zejian | Fang, Lie kui | Chen, Dong | Peng, Naixiong | Thakker, Parth Udayan | Schwartz, Marshall Zane | Zhang, Yuanyuan

Article Type: Research Article

Abstract: INTRODUCTION: Testicular infarction is a rare complication of prolonged epididymitis and may be misdiagnosed as testicular torsion. In this study, we present three cases of testicular infarction and discuss their clinical characteristics, imaging features and clinical management. PATIENTS AND METHODS: Three adult males with prolonged epididymitis presented with chronic unilateral testicular pain, tenderness, and palpable swelling, including left varicocele in one case and hydrocele in the other two cases. Patient’s symptoms were not relieved after antibiotic therapy. We analyzed the diagnosis, management, and outcome of these three cases of testicular infarction resulting from prolonged epididymitis. This includes the …clinical characteristics, features of color doppler ultrasound imaging for diagnosis, and treatment strategy for testicular infarction from prolonged epididymitis. RESULTS: Complete blood count (CBC) indicated a small leukocytosis (10.6±0.4×109 /L; normal arrange 3.5–9.5 WBC×109 /L). Color doppler images demonstrated appropriate blood flow to areas of interest at patient’s initial visit. At follow up visit several months later, the increased blood flow was detected at the edges of the involved testes with no blood flow to the center. The sizes of the involved testis (27±4 ml) was significantly larger compared to the non affected side (17±2 ml) (p  < 0.05 ). Unilateral simple orchiectomy was performed on the involved testis in all three cases. Grossly, abscess cavities with caseous necrosis were found at the center of the testicle and epididymis in two patients. Histopathologic examination showed chronic inflammation with lymphocytic and macrophage infiltration of the involved testicle in two cases. The third case stained positive for acid fast bacteria. Left varicocele disappeared postoperatively in one patient. No pain, wound infection or other discomfort were noted 12 months after surgery. COMMENTS: This series revealed that testicular infarction may result from inappropriately treated prolonged epididymitis. Epididymal tuberculosis should be considered in cases with epididymitis not responding to broad spectrum antibiotics. Testicular infarction induced by prolonged epididymitis is easily missed due to a lack of symptom changes. Color doppler images are helpful in the diagnosis. This usually presents as a decrease in blood flow at the center of the testis with the increased flow at the periphery differentiating this from testicular torsion. Show more

Keywords: Epididymitis, infarction, testicular, orchiectomy, tuberculosis

DOI: 10.3233/XST-200671

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-11, 2020

Authors: Anam, Choirul | Adhianto, Dwi | Sutanto, Heri | Adi, Kusworo | Ali, Mohd Hanafi | Rae, William Ian Duncombe | Fujibuchi, Toshioh | Dougherty, Geoff

Article Type: Research Article

Abstract: The objective of this study is to determine X-ray dose distribution and the correlation between central, peripheral and weighted-centre peripheral doses for various phantom sizes and tube voltages in computed tomography (CT). We used phantoms developed in-house, with various water-equivalent diameters (Dw) from 8.5 up to 42.1 cm. The phantoms have one hole in the centre and four holes at the periphery. By using these five holes, it is possible to measure the size-specific central dose (Ds,c), peripheral dose (Ds,p), and weighted dose (Ds,w).The phantoms are scanned using a CT scanner (Siemens Somatom Definition AS), with the tube voltage varied from …80 up to 140 kVps. The doses are measured using a pencil ionization chamber (Ray safe X2 CT Sensor) in every hole for all phantoms. The relationships between Ds,c, Ds,p, and Ds,w, and the water-equivalent diameter are established. The size-conversion factors are calculated. Comparisons between Ds,c, Ds,p, and Ds,ware also established. We observe that the dose is relatively homogeneous over the phantom for water-equivalent diameters of 12–14 cm. For water-equivalent diameters less than 12 cm, the dose in the centre is higher than at the periphery, whereas for water-equivalent diameters greater than 14 cm, the dose at the centre is lower than that at the periphery. We also find that the distribution of the doses is influenced by the tube voltage. These dose distributions may be useful for calculating organ doses for specific patients using their CT images in future clinical practice. Show more

Keywords: Dose distribution, size-specific dose estimate (SSDE), central dose, peripheral dose, weighted dose

DOI: 10.3233/XST-200667

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-14, 2020

Authors: Yang, Tiejun | Zhou, Yudan | Li, Lei | Zhu, Chunhua

Article Type: Research Article

Abstract: BACKGROUND: Brain tumor segmentation plays an important role in assisting diagnosis of disease, treatment plan planning, and surgical navigation. OBJECTIVE: This study aims to improve the accuracy of tumor boundary segmentation using the multi-scale U-Net network. METHODS: In this study, a novel U-Net with dilated convolution (DCU-Net) structure is proposed for brain tumor segmentation based on the classic U-Net structure. First, the MR brain tumor images are pre-processed to alleviate the class imbalance problem by reducing the input of the background pixels. Then, the multi-scale spatial pyramid pooling is used to replace the max pooling at …the end of the down-sampling path. It can expand the feature receptive field while maintaining image resolution. Finally, a dilated convolution residual block is combined to improve the skip connections in the training networks to improve the network’s ability to recognize the tumor details. RESULTS: The proposed model has been evaluated using the Brain Tumor Segmentation (BRATS) 2018 Challenge training dataset and achieved the dice similarity coefficients (DSC) score of 0.91, 0.78 and 0.83 for whole tumor, core tumor and enhancing tumor segmentation, respectively. CONCLUSIONS: The experiment results indicate that the proposed model yields a promising performance in automated brain tumor segmentation. Show more

Keywords: Brain tumor segmentation, dilated convolution, multi-scale spatial pyramid pooling, DCU-Net, U-Net

DOI: 10.3233/XST-200650

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-18, 2020

Authors: Li, Kuei-Liang | Lin, Jao-Perng | Chen, Yi-Ching | Lu, Chia-Chun

Article Type: Research Article

Abstract: During radiotherapy for head and neck tumours, the oral cavity and cheek area would be inevitably exposed to high energy radiation; thus, the material surface of the teeth, dental restorations with high atomic number, or alloy prosthodontics would generate backscatter electrons that cause the buccal mucosa adjacent to these materials to receive localized high dose enhancement, which primarily leads to side effects or oral mucositis. Based on the size of the adult oral cavity, this study aimed to use acrylic resin to create an oral phantom with two grooves on the left and right sides for placement of three molars. …Moreover, the distance between the inner cheek and the side surface of the teeth could be accurately adjusted every 1 mm from 0 to 5 mm. This enhanced the dose in the buccal mucosa during head and neck radiotherapy and made the distribution measurement of the radiation dose simple and feasible at different depths (0–5 mm). Meanwhile, the study employed the film type optically stimulated luminescent dosimeter with a thickness of 0.3 mm to measure the absorbed dose inside the buccal mucosa to reduce the dose interference from radiotherapy. The study fixed three real molars in a row located at the left side of the phantom and employed 6 MV photons and intensity-modulated radiotherapy (IMRT) to treat and simulate oral cancer and measure the attenuation of the molar’s backscatter dose from 0 to 5 mm in an up beam direction. The result showed that, in every 3 mm, the phantom had attenuated the enhancement of backscatter dose <3%. The irradiation dose enhancement in a single direction was twice higher than that through IMRT 7 field treatment. These measurement results were consistent with the results of previous studies. Show more

Keywords: Oral cavity, backscatter dose, dental restoration, mucositis, optically stimulated luminescent dosimeter

DOI: 10.3233/XST-200664

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-10, 2020

Authors: Ming, Ye | Hu, Yun | Wang, Tao | Zhang, Jiangtao | Li, Yuyue | Xu, Wenjie | Tan, Hao | Ye, Huayu | Zheng, Leilei

Article Type: Research Article

Abstract: OBJECTIVE: To evaluate skeletal and dental changes in patients with skeletal Class III malocclusion and facial asymmetry after surgical-orthodontic treatment using cone-beam computerized tomography (CBCT). METHODS: This study included forty adult patients diagnosed with skeletal Class III malocclusion and asymmetry who underwent either isolated mandibular surgery or bimaxillary surgery. CBCT scans were taken before treatment (T0), at the completion of presurgical orthodontic treatment (T1) and after treatment (T2). Mimics 17.0 and 3-Matics 7.0 were used to measure skeletal and dental parameters. Skeletal and dental changes within each group from pretreatment to posttreatment were assessed, and Pearson correlation analysis …was used to analyze the correlations among skeletal changes. RESULTS: The three-dimensional changes in condylar position were insignificant after surgical-orthodontic treatment in either group (P  > 0.05). However, in the one-jaw surgery group, there were significant backward rotations of the condyle and ramus on the nondeviated side (P  < 0.05), and the condyle on the deviated side rotated inward and forward significantly in the two-jaw surgery group (P  < 0.05) at T2. There were no significant differences in the changes in the total alveolar bone thickness of bilateral first molars during dental decompensation (P  > 0.05). The ratio between the buccal and the total bone thickness around the maxillary first molar on the deviated side decreased significantly at T1, as did those around the mandibular first molar on the nondeviated side (P  < 0.05). CONCLUSIONS: Condylar angulations were less stable after treatment (7 to 9 months after surgery) in both the one-jaw and the two-jaw surgery groups, while condylar displacements were insignificant. In addition, orthodontists should keep a watchful eye to the relative position of the root in the alveolar bone during tooth decompensation. Show more

Keywords: Skeletal class III patients with facial asymmetry, cone-beam computerized tomography (CBCT), surgical-orthodontic treatment

DOI: 10.3233/XST-190628

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-16, 2020

Authors: Shi, Liu | Liu, Baodong | Yu, Hengyong | Wei, Cunfeng | Wei, Long | Zeng, Li | Wang, Ge

Article Type: Research Article

Abstract: Computed tomography (CT) has been widely applied in medical diagnosis, nondestructive evaluation, homeland security, and other science and engineering applications. Image reconstruction is one of the core CT imaging technologies. In this review paper, we systematically reviewed the currently publicly available CT image reconstruction open source toolkits in the aspects of their environments, object models, imaging geometries, and algorithms. In addition to analytic and iterative algorithms, deep learning reconstruction networks and open codes are also reviewed as the third category of reconstruction algorithms. This systematic summary of the publicly available software platforms will help facilitate CT research and development.

Keywords: CT, image reconstruction, open source, toolkits, algorithm, analytic, iterative, deep learning

DOI: 10.3233/XST-200666

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-22, 2020

Authors: Hou, Yubao

Article Type: Research Article

Abstract: The automatic classification of breast cancer pathological images has important clinical application value. However, to develop the classification algorithm using the artificially extracted image features faces several challenges including the requirement of professional domain knowledge to extract and compute highiquality image features, which are often time-consuming, laborious, and difficult. For overcoming these challenges, this study developed and applied an improved deep convolutional neural network model to perform automatic classification of breast cancer using pathological images. Specifically, in this study, data enhancement and migration learning methods are used to effectively avoid the overfitting problems with deep learning models when they are …limited by training image sample size. Experimental results show that a 91% recognition rate or accuracy when applying this improved deep learning model to a publicly available dataset of BreaKHis. Comparing with other previously used models, the new model yields good robustness and generalization. Show more

Keywords: Breast cancer histopathological image classification, deep leaning, convolutional neural network, transfer learning, data augmentation, open dataset of BreaKHis

DOI: 10.3233/XST-200658

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-12, 2020

Authors: Farhood, Bagher | Mohammadi ASL, Kamal | Sarvizadeh, Mostafa | Aliasgharzadeh, Akbar

Article Type: Research Article

Abstract: OBJECTIVE: Several physical factors such as dose rate and photon energy may change response and sensitivity of polymer gel dosimeters. This study aims to evaluate the R 2 -dose response and sensitivity dependence of PASSAG-U gel dosimeters with 3% and 5% urea on dose rate and photon energy. MATERIALS AND METHODS: The PASSAG-U gel dosimeters were prepared under normal atmospheric conditions. The obtained gel dosimeters were irradiated to different dose rates (100, 200, and 300 cGy/min) and photon energies (6 and 15 MV). Finally, responses (R 2 ) of the PASSAG-U gel dosimeters with 3% and 5% urea were analyzed …by MRI technique at 1, 10, 14 days after the irradiation process. RESULTS: The findings showed that the R 2 -dose responses of PASSAG-U gel dosimeters with 3% and 5% urea do not vary under the differently evaluated dose rates and photon energies. The R 2 -dose sensitivity of PASSAG-U polymer gel dosimeter with 3% urea does not change under the differently evaluated dose rates and photon energies, but it changes for PASSAG-U polymer gel dosimeter with 5% urea. The dose resolution values ranged from 0.20 to 0.86 Gy and from 0.27 to 2.20 Gy for the PASSAG-U gel dosimeter with 3% and 5% urea for the different dose rates and photon energies, respectively. Furthermore, it was revealed that the R 2 -dose response and sensitivity dependence of PASSAG-U gel dosimeters with 3% and 5% urea on dose rate and photon energy can vary over post irradiation time. CONCLUSIONS: The study results demonstrated that dosimetric characteristics (dependence of dose rate and photon energy, and dose resolution) of PASSAG-U gel dosimeter with 3% were better than those of PASSAG-U gel dosimeter with 5% urea. Show more

Keywords: Polymer gel dosimetry, PASSAG-U, urea, photon energy, dose rate

DOI: 10.3233/XST-190625

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-18, 2020

Authors: Khan, Sajid Ullah | Khan, Imran Ullah | Ullah, Imad | Saif, Naveed | Ullah, Irfan

Article Type: Research Article

Abstract: In this paper, we present a review of the research literature regarding applying X-ray imaging of baggage scrutiny at airport. It discusses multiple X-ray imaging inspection systems used in airports for detecting dangerous objects inside the baggage. Moreover, it also explains the dual energy X-ray image fusion and image enhancement factors. Different types of noises in digital images and noise models are explained in length. Diagrammatical representations for different noise models are presented and illustrated to clearly show the effect of Poisson and Impulse noise on intensity values. Overall, this review discusses in detail of Poisson and Impulse noise, as …well as its causes and effect on the X-ray images, which create un-certainty for the X-ray inspection imaging system while discriminating objects and for the screeners as well. The review then focuses on image processing techniques used by different research studies for X-ray image enhancement, de-noising, and their limitations. Furthermore, the most related approaches for noise reduction and its drawbacks are presented. The methods that may be useful to overcome the drawbacks are also discussed in subsequent sections of this paper. In summary, this review paper highlights the key theories and technical methods used for X-ray image enhancement and de-noising effect on X-ray images generated by the airport baggage inspection system. Show more

Keywords: Airport baggage inspection, X-ray imaging, poisson noise, image enhancement, noise reduction, noise causes

DOI: 10.3233/XST-200663

Citation: Journal of X-Ray Science and Technology, vol. Pre-press, no. Pre-press, pp. 1-25, 2020