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The effect of Mepitel Film on acute radiation-induced skin reactions in head and neck cancer patients: a feasibility study

第一作者:Wooding, H

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: Mepitel Film significantly decreases acute radiation-induced skin reactions in breast cancer patients. Here we investigated the feasibility of using Mepitel Film in head and neck cancer patients (ACTRN12614000932662). Methods: Out of a total of 36 head and neck cancer patients from New Zealand (NZ) (n = 24) and China (n = 12) recruited between June 2015 and December 2016, 33 patients complied with protocol. Of these, 11 NZ patients followed a management protocol; 11 NZ patients and 11 Chinese patients followed a prophylactic protocol. An area of the neck receiving a homogenous radiation dose of > 35 Gy was divided into two equal halves; one half was randomized to Film and the other to either Sorbolene cream (NZ) or Biafine cream (China). Skin reaction severity was measured by Radiation Induced Skin Reaction Assessment Scale and expanded Radiation Therapy Oncology Group toxicity criteria. Skin dose was measured by thermoluminescent dosimeters or gafchromic film. Results: Film decreased overall skin reaction severity (combined Radiation Induced Skin Reaction Assessment Scale score) by 29% and moist desquamation rates by 37% in the Chinese cohort and by 27 and 28%, respectively in the NZ cohort. Mepitel Film did not affect head movements but did not adhere well to the skin, particularly in males with heavy beard stubble, and caused itchiness, particularly in Chinese patients. Conclusion: Mepitel Film reduced acute radiation-induced skin reactions in our head and neck cancer patients, particularly in patients without heavy stubble.

IF:1.94

Assessment of noise reduction potential and image quality improvement of a new generation adaptive statistical iterative reconstruction (ASIR-V) in chest CT

第一作者:Tang, H

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: To evaluate the image quality improvement and noise reduction in routine dose, non-enhanced chest CT imaging by using a new generation adaptive statistical iterative reconstruction (ASIR-V) in comparison with ASIR algorithm. Methods: 30 patients who underwent routine dose, non-enhanced chest CT using GE Discovery CT750 HU (GE Healthcare, Waukesha, WI) were included. The scan parameters included tube voltage of 120 kVp, automatic tube current modulation to obtain a noise index of 14HU, rotation speed of 0.6 s, pitch of 1.375:1 and slice thickness of 5 mm. After scanning, all scans were reconstructed with the recommended level of 40% ASIR for comparison purpose and different percentages of ASIR-V from 10% to 100% in a 10% increment. The CT attenuation values and SD of the subcutaneous fat, back muscle and descending aorta were measured at the level of tracheal carina of all reconstructed images. The signal-to-noise ratio (SNR) was calculated with SD representing image noise. The subjective image quality was independently evaluated by two experienced radiologists. Results: For all ASIR-V images, the objective image noise (SD) of fat, muscle and aorta decreased and SNR increased along with increasing ASIR-V percentage. The SD of 30% ASIR-V to 100% ASIR-V was significantly lower than that of 40% ASIR (p < 0.05). In terms of subjective image evaluation, all ASIR-V reconstructions had good diagnostic acceptability. However, the 50% ASIR-V to 70% ASIR-V series showed significantly superior visibility of small structures when compared with the 40% ASIR and ASIR-V of other percentages (p < 0.05), and 60% ASIR-V was the best series of all ASIR-V images, with a highest subjective image quality. The image sharpness was significantly decreased in images reconstructed by 80% ASIR-V and higher. Conclusion: In routine dose, non-enhanced chest CT, ASIR-V shows greater potential in reducing image noise and artefacts and maintaining image sharpness when compared to the recommended level of 40% ASIR algorithm. Combining both the objective and subjective evaluation of images, non-enhanced chest CT images reconstructed with 60% ASIR-V have the highest image quality.

IF:1.94

T3 subclassification using the EMD/mesorectum ratio predicts neoadjuvant chemoradiation outcome in T3 rectal cancer patients

第一作者:Shen, LJ

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: To evaluate the feasibility of the EMD (extramural depth)/mesorectum ratio as a marker for T3 rectal cancer and its ability to predict tumour response to neoadjuvant chemoradiation and survival. Methods: From 2010 to 2016, 284 T3 rectal cancer patients who underwent high resolution MRI before neoadjuvant chemoradiation were enrolled. The EMD was defined as the distance from the outer edge of the muscularis propria to the outermost edge of the tumour. The measurement of the tumour EMD and mesorectum was in the same layer and their ratio was calculated. Receiver operating characteristic analysis and relative area under the curve statistics were used to choose the cut-off value. The association of the EMD/mesorectum ratio and other MRI or clinical factors with the tumour regression grade (TRG) was analysed. Cox regression analysis was used to estimate independent risk factors for disease-free survival (DFS) and overall survival (OS). Results: The mean EMD/mesorectum ratio was 0.47 +/- 0.3. We chose an EMD/mesorectum ratio of 0.5 in further analyses after receiver operating characteristic analysis. Of 284 patients, 177 (62.3%) had an EMD/mesorectum ratio <= 0.5. Patients with an EMD/mesorectum ratio <= 0.5 had a higher TRG 0-1 rate than patients with a ratio > 0.5 (53.1% vs 36.4%, p = 0.006). A multivariate analysis identified that an EMD/mesorectum ratio > 0.5 [hazard ratio (HR) 2.020; p = 0.028] and ypTNM II-III (HR 3.550; p = 0.017) were independent prognostic factors to indicate decreased DFS. For OS, only patients with TRG 2-3 had decreased OS compared with patients with TRG 0-1 (HR 2.959; p = 0.035). Conclusion: When the EMD/mesorectum ratio was applied to categorize T3 rectal cancer patients, the ratio of 0.5 can be used as a cut-off value for T3 rectal cancer. Patients with a ratio <= 0.5 had a higher response rate and better DFS. However, further validation is needed in a larger sample of patients.

IF:1.94

Cervical cancer treated with reduced-volume intensity-modulated radiation therapy base on Sedlis criteria (NCCN VS RTOG)

第一作者:Luo, HC

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: This study aimed to evaluate the clinical efficacy of different target volumes in pelvic radiotherapy in postoperative treatment of cervical cancer based on the Sedlis criteria. Methods: Patients who admitted to our department for post-operative radiotherapy of cervical cancer from December 2001 to December 2011 and met the Sedlis criteria were retrospectively analysed. The incidences of acute and late radiation injuries, and overall, disease-free and tumour-specific survival with reduced-volume pelvic and whole-pelvis radiotherapy were evaluated and compared. Results: A total of 371 patients were included in the study, including 239 receiving whole-pelvis radiotherapy and 132 receiving reduced-volume pelvic radiotherapy. The volume of contours for mean PTV volumes, bilateral femoral heads and small intestine volumes in reduced-volume pelvic radiotherapy were lower than whole-pelvis radiotherapy; the results were similar to the V10, V20, V30, V40 and V45 for pelvic bone marrow and small intestine dose volume (both p < 0.05). The acute radiation injury observed in the two groups was mainly haematologic toxicity and upper and lower gastrointestinal symptoms. The incidences of acute radiation injury, and late radiation injury of gastrointestinal and urinary tracts were both significantly lower with reduced-volume pelvic radiotherapy than with whole-pelvis radiotherapy (both p < 0.05). Moreover, there was no significant difference in the incidence of lower extremity oedema, or 2-year or 5-year overall, disease-free or tumour-specific survival between groups (all p > 0.05). Conclusion: Reduced-volume pelvic radiotherapy could relieve acute and late radiation injuries, especially myelosuppression, and did not affect long-term survival.

IF:1.94

Interrater reliability and radiation dosage of oblique coronal computed tomography

第一作者:Li, SG

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: Sacroiliitis, a prerequisite to the diagnosis of ankylosing spondylitis, can be ascertained by CT when MRI is not available. Oblique coronal CT is an increasingly popular approach when examining sacroiliitis. The goal of this study was to understand how oblique coronal CT compared with axial CT scanning in terms of raters' concordance when diagnosing sacroiliitis. Methods: 52 subjects < 45 years of age at onset of their chronic lower back pain were sequentially scanned by X-ray, axial CT and oblique coronal CT. The acquired images were graded by two experienced, double-blinded physicians. Results: Sacroiliitis in the oblique coronal view was sensitive enough for grading disease severity and/or detecting improvement. Interrater reliability for CT (axial + oblique coronal) was higher than X-ray. The diagnosis based upon oblique coronal CT was consistent, while the radiation dose delivered to the gonads was significantly reduced, compared with axial CT. Conclusion: When MRI is not available, oblique coronal CT should replace axial CT when diagnosing sacroiliitis.

IF:1.94

Effectiveness and safety of CT-guided percutaneous radiofrequency ablation of adrenal metastases

第一作者:Zhou, K

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: The imaging-guided percutaneous radiofrequency (RF) ablation of adrenal metastases is a relatively new treatment procedure, compared to the more widespread application of the technique for the treatment of liver and renal cancers. The present study aims to evaluate the safety and efficacy of the CT-guided percutaneous RF ablation of adrenal metastases in a cohort of patients. Methods: 33 patients with 38 adrenal metastases who received percutaneous CT-guided RF ablation between 2012 to 2015 were retrospectively reviewed. The average diameter of the treated adrenal metastases was 3.0 +/- 1.6cm. The treatment outcomes, including presence of residual tumours, technical success rate, recurrence rate, and complications, were evaluated. Patients were followed up for every 3 months to monitor the progression of the disease. Results: Postoperative CT images showed the lack of tumour enhancement in 30 tumours (30/38 tumours, technical success rate = 78.9%), and residual disease was found in 7 tumours (7/37 tumours, 18,9%). The rate of residual disease was significantly lower in the group with tumour size <3 cm than the group with tumour size >3 cm (p = 0.025). The severe complication rate was 4.3%, and the mild complication rate was 48%, with intraoperative hypertensive crisis as the most frequently observed complication (27.3%). The follow-up data showed that 76.3% of patients had recurrence-free survival in 27.4 months. Conclusion: The current study demonstrated that radiofrequency ablation is a relatively safe and effective treatment for controlling adrenal metastases, especially for patients with tumour size <3cm. Advances in knowledge: Surgical resection of the adrenal metastases was advocated as one of the treatment options for patients. The present study showed that radiofrequency ablation is a relatively safe and effective treatment for controlling adrenal metastases.

IF:1.94

Preoperative evaluation of neurovascular relationship in trigeminal neuralgia by three-dimensional fast low angle shot (3D-FLASH) and three-dimensional constructive interference in steady-state (3D-CISS) MRI sequence

第一作者:Yang, DF

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: The purpose of the study was to evaluate the value of high-resolution three-dimensional fast low angle shot (3D-FLASH) and three-dimensional constructive interference in steady-state (3D-CISS) MRI sequence solely or the combination of both in the visualization of neurovascular relationship in patients with trigeminal neuralgia (TN). Methods: 65 patients with unilateral TN underwent 3D-FLASH and 3D-CISS imaging were retrospectively studied. Neurovascular relationship at the intracisternal segment of trigeminal nerve was reviewed by two experienced neuroradiologist, who was blinded to the clinical details. The imaging results were compared with the operative findings in all patients. Results: The accuracy and positive rates of the 3D-FLASH + CISS imaging (98.46, 92.31%) in judging the symptomatic side according to the presence of vascular contacts were higher than those of 3D-CISS (90.77%, 84.62) or 3D-FLASH (89.23, 83.08%) sequence. In addition, the statistical analysis showed the sensitivity and accuracy of 3D-FLASH + CISS imaging was higher than that of 3D-FLASH (p < 0.05). The 3D-FLASH + CISS imaging was more accurate in determining the type of offending vessel than 3D-CISS or 3D-FLASH imaging. Conclusion: The retrospective study demonstrates that the combination of 3D-FLASH with 3D-CISS sequence well delineates the relationship between intracisternal segment of trigeminal nerve and adjacent vessels in terms of increased positive rates and accuracy. Advances in knowledge: The study firstly dealt with the combination of 3D-CISS and 3D-FLASH imaging in TN.

IF:1.94

Ultrasound elastography as an imaging biomarker for detection of early tumor response to chemotherapy in a murine breast cancer model: a feasibility study

第一作者:Wang, JW

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: This study investigated the feasibility of using strain elastography (SE) and real time shear wave elastography (RT-SWE) to evaluate early tumor response to cytotoxic chemotherapy in a murine xenograft breast cancer tumor model. Methods: MCF-7 breast cancer-bearing nude mice were treated with either cisplatin 2mg kg(-1) plus paclitaxel 10 mg kg(-1) (treatment group) or sterile saline (control group) once daily for 5 days. The tumor elasticity was measured by SE or RT-SWE before and after therapy, Tumor cell density was assessed by hematoxylin and eosin staining, and the ratio of collagen fibers in the tumor was evaluated by Van Gieson staining. The correlation between tumor elasticity, as determined by SE and SWE, as well as the pathological tumor responses were analyzed. Results: Chemotherapy significantly attenuated tumor growth compared to the control treatment (p < 0.05), Chemotherapy also significantly increased tumor stiffness (p < 0.05) and significantly decreased (p < 0.05) tumor cell density compared with the control. Moreover, chemotherapy significantly increased the ratio of collagen fibers (p < 0.05). Tumor stiffness was positively correlated with the ratio of collagen fibers but negatively correlated with tumor cell density. Conclusion: The study suggests that ultrasound elastography by SE and SWE is a feasible tool for assessing early responses of breast cancer to chemotherapy in our murine xenograft model. Advances in knowledge: This study showed that the tumor elasticity determined by ultrasound elastography could be a feasible imaging biomarker for assessing very early therapeutic responses to chemotherapy.

IF:1.94

Histogram analysis of apparent diffusion coefficient maps for assessing thymic epithelial tumours: correlation with world health organization classification and clinical staging

第一作者:Kong, LY

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: To investigate the value of apparent diffusion coefficients (ADCs) histogram analysis for assessing World Health Organization (WHO) pathological classification and Masaoka clinical stages of thymic epithelial tumours. Methods: 37 patients with histologically confirmed thymic epithelial tumours were enrolled. ADC measurements were performed using hot-spot ROI (ADC(HS-ROI)) and histogram-based approach. ADC histogram parameters included mean ADC (ADC(mean)), median ADC (ADC(median)), 10 and 90 percentile of ADC (ADC(10) and ADC(90)), kurtosis and skewness, One-way ANOVA, independent-sample t-test, and receiver operating characteristic were used for statistical analyses. Results: There were significant differences in ADC(mean), ADC(media), ADC(10), ADC(90) and ADC(HS-ROI) among low-risk thymoma (type A, AB, B1; n = 14), high-risk thymoma (type 82, B3; n = 9) and thymic carcinoma (type C, n = 14) groups (all p-values <0.05), while no significant difference in skewness (p = 0.181) and kurtosis (p = 0.088). ADC(10) showed best differentiating ability (cut-off value, <= 0.689 x 10(-3) mm(2) s(-1); AUC, 0.957; sensitivity, 95.65%; specificity, 92.86%) for discriminating low-risk thymoma from high-risk thymoma and thymic carcinoma. Advanced Masaoka stages (Stage III and IV; n = 24) tumours showed significant lower ADC parameters and higher kurtosis than early Masaoka stage (Stage I and II; n = 13) tumours (all p-values <0.05), while no significant difference on skewness (p = 0.063). ADC(10) showed best differentiating ability (cut-off value, <= 0.689 x 10(-3) mm(2) s(-1); AUC, 0.913; sensitivity, 91.30%; specificity, 85.71%) for discriminating advanced and early Masaoka stage epithelial tumours. Conclusion: ADC histogram analysis may assist in assessing the WHO pathological classification and Masaoka clinical stages of thymic epithelial tumours. Advances in knowledge: 1. ADC histogram analysis could help to assess WHO pathological classification of thymic epithelial tumours. 2. ADC histogram analysis could help to evaluate Masaoka clinical stages of thymic epithelial tumours. 3. ADC 10 might be a promising imaging biomarker for assessing and characterizing thymic epithelial tumours.

IF:1.94

Intravoxel incoherent motion diffusion-weighted imaging of resectable oesophageal squamous cell carcinoma: association with tumour stage

第一作者:Huang, YC

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: To determine whether intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) derived parameters can be associated with tumour stage of oesophageal squamous cell carcinoma (SCC). Methods: 60 patients with resectable oesophageal SCC and 20 healthy individuals underwent oesophageal DWI-using multi b-values with a 3.0T MR system. Pure diffusion coefficient (D), perfusion-related incoherent microcirculation (D"), microvascular volume fraction (f) and apparent diffusion coefficient (ADC) were measured on DWI. Statistical analyses were performed to determine associations of DWI-derived parameters with T-stage. Results: ADC (r = -0.842), D (r = -0.729), D* (r = -0.301) and f (r = -0.817) were negatively correlated with T-stage of oesophageal SCC (all p < 0.01), and the multinominal regression analyses revealed that IVIM-derived parameters including D (p = 0.038; odds ratio <1) and f (p < 0.001; odds ratio <1) were associated with T-stage. The Mann-Whitney U tests with Bonferroni correction showed that D, f and ADC could discriminate oesophageal SCC, especially T-1-staged tumour, from normal oesophagus (all p < 0.05) while D* could not (p > 0.05). By receiver operating characteristic analyses, f could be the best indicator for detecting oesophageal SCC with an area under receiver operating characteristic (AUC) of 0.964, especially T-1- staged cancer with an AUC of 0.984, and for discriminating T-1-stages between T0-1 and T2-3 with an AUC of 0.957, and between T0-2 and T-3 with an AUC of 0.945 in comparison with any other DWI-derived parameter. Conclusions: IVIM derived parameters can be associated with T-stage of oesophageal SCC. Advances in knowledge (1) IVIM-derived parameters are negatively correlated with stage of oesophageal SCC. (2) Among IVIM-derived parameters, microvascular volume fraction helps detect and stage oesophageal SCC.

IF:1.94

Effectiveness of tomotherapy vs linear accelerator image-guided intensity-modulated radiotherapy for localized pharyngeal cancer treated with definitive concurrent chemoradiotherapy: a Taiwanese population-based propensity score-matched analysis

第一作者:Wang, YC

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: This study used a population-based propensity score (PS)-matched analysis to compare the effectiveness of tomotherapy-based image-guided intensity-modulated radiotherapy (referred to as T-IMRT) with that of linear accelerator based (referred to as L-IMRT) for clinically localized pharyngeal cancer (LPC, divided into nasopharyngeal cancer and non-nasopharyngeal cancer) with definitive concurrent chemoradiotherapy (CCRT). Methods: Eligible LPC patients diagnosed between 2007 and 2014 were identified among all citizens in Taiwan from the Health and Welfare Data Science Center database. A PS-matched sample based on the PS estimated from the covariables of interest was constructed to compare the effectiveness of T-IMRT with L-IMRT. In the primary analysis, overall survival (OS) was compared for assessment of effectiveness. We also evaluated freedom from local regional recurrence and pharyngeal cancer-specific survival arid performed supplementary analyses. Results: The study population included 960 patients equally divided into two groups. OS did not differ significantly between the T-IMRT and L-IMRT groups (hazard ratio for death: 0.82, p = 0.15, 5-year OS rate: 79 and 74% for T-IMRT and L-IMRT, respectively), and there were no significant differences in the other endpoints or supplementary analyses. Conclusion: For LPC patients treated with definitive CCRT, we found no significant difference in disease control or survival between the T-IMRT and L-IMRT groups. However, further studies, especially randomized trials or studies focusing on other dimensions, such as quality of life, are needed. Advances in knowledge: We provide the first population-based study, as well as the largest study, on the clinical effectiveness of T-IMRT compared with L-IMRT in conjunction with CCRT in LPC patients.

IF:1.94

The value of multi ultra high-b-value DWI in grading cerebral astrocytomas and its association with aquaporin-4

第一作者:Tan, Y

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: To investigate the value of multi-ultrahighb-value diffusion-weighted imaging (UHBV-DWI) in differentiating high-grade astrocytomas (HGAs) from low-grade astrocytomas (LGAs), analyze its association with aquaporin (AQP) expression. Methods: 40 astrocytomas divided into LGAs (N = 15) and HGAs (N = 25) were studied. Apparent diffusion coefficient (ADC) and UHBV-ADC values in solid parts and peritumoral edema were compared between LGAs and HGAs groups by the t-test. Using receiver operating characteristic curves to identify the better parameter. Using real time polymerase chain reaction to assess AQP messenger ribonucleic acid (mRNA). Using spearman correlation analysis to assess the correlation of AQP mRNA with each parameter. Results: ADC values in solid parts of HGAs were significantly lower than LGAs (p = 0.02), while UHBV-ADC values of HGAs were significantly higher than LGAs (p < 0.01). Area under the curve (AUC) of UHBV-ADC (0.810) was larger than ADC (0.713), and the area under the curve of UHBV-ADC was significantly higher than that of ADC (p = 0.041). AQP4 mRNA was significantly higher in HGAs than that in LGAs (p < 0.01); there was less AQP9 mRNA and no AQP1 mRNA in LGAs and HGAs groups (p > 0.05); ADC value showed a negative correlation with AQP4 mRNA (r = -0.357; p = 0.024). UHBV-ADC value positively correlated with the AQP4 mRNA (r = 0.646; p < 0.01). Conclusion: UHBV-DWI allowed for a more accurate grading of cerebral astrocytoma than DWI, and UHBV-ADC value may be related with the AQP4 mRNA levels. UHBV-DWI could be of value in the assessment of astrocytoma. Advances in knowledge: UHBV-DWI generated by multi UHBV could have particular value for astrocytoma grading, and the level of AQP4 mRNA might be potentially linked to the change of UHBV-DWI parameter, and we might find the exact reason for the difference of UHBV-ADC between the LGAs and HGAs.

IF:1.94

Subtraction CT angiography in head and neck with low radiation and contrast dose dual-energy spectral CT using rapid kV-switching technique

第一作者:Ma, GM

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: To investigate the application of low radiation and contrast dose spectral CT angiology using rapid kV-switching technique in the head and neck with subtraction method for bone removal. Methods: This prospective study was approved by the local ethics committee. 64 cases for head and neck CT angiology were randomly divided into Groups A (n = 32) and B (n = 32). Group A underwent unenhanced CT with 100 kVp, 200 mA and contrast-enhanced CT with spectral CT mode with body mass index-dependent low dose protocols. Group B used conventional helical scanning with 120 kVp, auto mA for noise index of 12 HU (Hounsfield unit) for both the unenhanced and contrast-enhanced CT. Subtraction images were formed by subtracting the unenhanced images from enhanced images (with the 65 keV-enhanced spectral CT image in Group A). CT numbers and their standard deviations in aortic arch, carotid arteries, middle cerebral artery and air were measured in the subtraction images. The signal-to-noise ratio and contrast-to-noise ratio for the common and internal carotid arteries and middle cerebral artery were calculated. Image quality in terms of bone removal effect was evaluated by two experienced radiologists independently and blindly using a 4-point system. Radiation dose and total iodine load were recorded. Measurements were statistically compared between the two groups. Results: The two groups had same demographic results. There was no difference in the CT number, signal-to-noise and contrast-to-noise ratio values for carotid arteries and middle cerebral artery in the subtraction images between the two groups (p > 0.05). However, the bone removal effect score [median (min-max)] in Group A [4 (3-4)] was rated better than in Group B [3 (2-4)] (p < 0.001), with excellent agreement between the two observers (kappa > 0.80). The radiation dose in Group A (average of 2.64 mSv) was 57% lower than the 6.18mSv in Group B (p < 0.001). The total iodine intake in Group A was 13.5g, 36% lower than the 21g in Group B. Conclusion: Spectral CT imaging with rapid kV-switching in the subtraction angiography in head and neck provides better bone removal with significantly reduced radiation and contrast dose compared with conventional subtraction method. Advances In knowledge: This novel method provides better bone removal with significant radiation and contrast dose reduction compared with the conventional subtraction CT, and maybe used clinically to protect the thyroid gland and ocular lenses from unnecessary high radiation.

IF:1.94

Performance of U-net based pyramidal lucas-kanade registration on free-breathing multi-b-value diffusion MRI of the kidney

第一作者:Lv, J

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: In free-breathing multi-b-value diffusion-weighted imaging (DWI), a series of images typically requires several minutes to collect. During respiration the kidney is routinely displaced and may also undergo deformation. These respiratory motion effects generate artifacts and these are the main sources of error in the quantification of intravoxel incoherent motion (IVIM) derived parameters. This work proposes a fully automated framework that combines a kidney segmentation to improve the registration accuracy. Methods: 10 healthy subjects were recruited to participate in this experiment. For the segmentation, U-net was adopted to acquire the kidney's contour. The segmented kidney then served as a region of interest (ROI) for the registration method, known as pyramidal Lucas-Kanade. Our proposed framework confines the kidney's solution range, thus increasing the pyramidal Lucas-Kanade's accuracy. To demonstrate the feasibility of our presented framework, eight regions of interest were selected in the cortex and medulla, and data stability was estimated by comparing the normalized root-mean-square error (NRMSE) values of the fitted data from the bi-exponential intravoxel incoherent motion model pre and post- registration. Results: The results show that the NRMSE was significantly lower after registration both in the cortex (p < 0.05) and medulla (p < 0.01) during free-breathing measurements. In addition, expert visual scoring of the derived apparent diffusion coefficient (ADC), f, D and D* maps indicated there were significant improvements in the alignment of the kidney in the post-registered image. Conclusion: The proposed framework can effectively reduce the motion artifacts of misaligned multi-b-value DWIs and the inaccuracies of the ADC, f, D and D* estimations. Advances in knowledge: This study demonstrates the feasibility of our proposed fully automated framework combining U-net based segmentation and pyramidal Lucas-Kanade registration method for improving the alignment of multi-b-value diffusion-weighted MRIs and reducing the inaccuracy of parameter estimation during free-breathing.

IF:1.94

Clinical and imaging features of Kaposiform Hemangioendothelioma

第一作者:Hu, PA

期刊: BRITISH JOURNAL OF RADIOLOGY, 2018; 91 (无)

Objective: Kaposiform hernang end hell a (KHE) s a unique locally aggressive vascular tumor with poor prognosis. The aim of this study is to assess the clinical and imaging features of KHE, and to compare the differences between solitary and diffusive infiltrative subtype further. Methods: The clinical and radiological findings of a cohort of 25 cases with histologically proven KHE, between June 2011 and June 2016, were reviewed retrospectively. 7 solitary and 18 diffusive infiltrative subtypes KHE were included. The differences of clinical and imaging features between these two subtypes were compared statistically by Wilcoxon rank sum test and Fisher exact test. Results: The median age was 4 months old. 20 cases (80%) were accompanied by Kasabach-Merritt phenomenon (KMP). Most KHE located in trunk and/or extremity. The masses showed inhomogeneous echogenicity and were rich in vascularity on ultrasound: showed isoattenuation relative to muscle on unenhanced CT, isointense (n = 15) or slightly hyperintense (n = 7) T-1 weighted imaging (T1WI) signal relative to muscle, mainly heterogeneous hyperintense or htly hyperintense with speckled hypointense (n = 17) T2WI signal (77%) relative to muscle, and notable (n = 15) and moderate (n = 3) enhancement. Feeding and draining vessels were revealed in 15 cases. Five masses with DWI showed slightly restricted diffusivity, with average apparent diffusion coefficient value of (1.28 +/- 0.09) x 10(-3) mm(2) s(-1). Necrosis and hemorrhage were also found. Compared with solitary ones, diffusive infiltrative KHE were larger, more commonly accompanied by KMP and reticular lymphedema, and more frequently located in trunk and/or extremity. Conclusion: Five masses with DWI showed slightly restricted diffusivity. A hypervascular mass accompanied by KMP and reticular lymphedema, with speckled hypointense signal T2WI signal, especially in pediatric patients, is highly suggestive of the diagnosis of KHE. Advances in knowledge: Speckled hypointense signal T2WI signal, and notable enhancement were unique features of KHE. KHE showed slightly restricted diffusivity on DWI, commonly accompanied by KMP and reticular lymphedema.

IF:1.94

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