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Scientific Reports Nov 2021Our aim was to investigate whether the previously observed higher contrast-to-noise ratio (CNR) and better image quality of Digital Variance Angiography (DVA) - compared...
Our aim was to investigate whether the previously observed higher contrast-to-noise ratio (CNR) and better image quality of Digital Variance Angiography (DVA) - compared to Digital Subtraction Angiography (DSA) - can be used to reduce radiation exposure in lower limb X-ray angiography. This prospective study enrolled 30 peripheral artery disease patients (mean ± SD age 70 ± 8 years) undergoing diagnostic angiography. In all patients, both normal (1.2 µGy/frame; 100%) and low-dose (0.36 µGy/frame; 30%) protocols were used for the acquisition of images in three anatomical regions (abdominal, femoral, crural). The CNR of DSA and DVA images were calculated, and the visual quality was evaluated by seven specialists using a 5-grade Likert scale. For investigating non-inferiority, the difference of low-dose DVA and normal dose DSA scores (DVA30-DSA100) was analyzed. DVA produced two- to three-fold CNR and significantly higher visual score than DSA. DVA30 proved to be superior to DSA100 in the crural region (difference 0.25 ± 0.07, p < 0.001), and there was no significant difference in the femoral (- 0.08 ± 0.06, p = 0.435) and abdominal (- 0.10 ± 0.09, p = 0.350) regions. Our data show that DVA allows about 70% reduction of DSA-related radiation exposure in lower limb X-ray angiography, providing a potential new radiation protection tool for the patients and the medical staff.
Topics: Aged; Aged, 80 and over; Angiography, Digital Subtraction; Female; Humans; Leg; Male; Middle Aged; Peripheral Vascular Diseases; Prospective Studies; Radiation Dosage; Radiography, Abdominal; Signal-To-Noise Ratio
PubMed: 34750427
DOI: 10.1038/s41598-021-01208-3 -
Annals of the Royal College of Surgeons... May 2017Introduction A colorectal inflammatory myofibroblastic tumour (IMT) is a rare but benign entity masquerading as a malignant tumour. Although the lung is considered the...
Introduction A colorectal inflammatory myofibroblastic tumour (IMT) is a rare but benign entity masquerading as a malignant tumour. Although the lung is considered the most common site of occurrence, IMTs may arise in diverse extrapulmonary locations. We describe a case of a colonic IMT in a patient who presented in the emergency setting. Case History A 77-year-old man was admitted at our emergency department with acute abdominal pain. Physical examination revealed vague tenderness of the lower abdomen and non-palpable masses. Preoperative evaluation revealed a mass in the right lower quadrant of the abdomen, possibly originating from the terminal ileum, 1-2cm from the caecum. Owing to the clinical impression of a potentially malignant lesion, the patient underwent subtotal colectomy and omentectomy. The pathology report suggested the morphological and immunohistochemical features were more compatible with a colonic IMT. Conclusions A colorectal IMT is a rare clinical entity that can easily mimic a highly malignant tumour and cannot be distinguished clinically or radiologically. An accurate diagnosis is based on histological examination and surgical resection is therefore usually required.
Topics: Abdominal Pain; Aged; Colon; Colonic Neoplasms; Granuloma, Plasma Cell; Humans; Male; Radiography, Abdominal; Tomography, X-Ray Computed
PubMed: 28462661
DOI: 10.1308/rcsann.2017.0064 -
The Canadian Veterinary Journal = La... Oct 2015Abdominal radiography and ultrasonography are commonly used as part of the initial diagnostic plan for cats with nonspecific signs of abdominal disease. This...
Abdominal radiography and ultrasonography are commonly used as part of the initial diagnostic plan for cats with nonspecific signs of abdominal disease. This retrospective study compared the clinical usefulness of abdominal radiography and ultrasonography in 105 feline patients with signs of abdominal disease. The final diagnosis was determined more commonly with ultrasonography (59%) compared to radiography (25.7%). Ultrasonography was also able to provide additional clinically relevant information in 76% of cases, and changed or refined the diagnosis in 47% of cases. Based on these findings, ultrasonography may be sufficient as an initial diagnostic test for the investigation of feline abdominal disease.
Topics: Abdomen; Animals; Cat Diseases; Cats; Radiography, Abdominal; Retrospective Studies; Sensitivity and Specificity; Ultrasonography
PubMed: 26483582
DOI: No ID Found -
AJR. American Journal of Roentgenology Jul 2016Automated analysis of abdominal CT has advanced markedly over just the last few years. Fully automated assessment of organs, lymph nodes, adipose tissue, muscle, bowel,... (Review)
Review
OBJECTIVE
Automated analysis of abdominal CT has advanced markedly over just the last few years. Fully automated assessment of organs, lymph nodes, adipose tissue, muscle, bowel, spine, and tumors are some examples where tremendous progress has been made. Computer-aided detection of lesions has also improved dramatically.
CONCLUSION
This article reviews the progress and provides insights into what is in store in the near future for automated analysis for abdominal CT, ultimately leading to fully automated interpretation.
Topics: Automation; Forecasting; Humans; Radiographic Image Interpretation, Computer-Assisted; Radiography, Abdominal; Tomography, X-Ray Computed
PubMed: 27101207
DOI: 10.2214/AJR.15.15996 -
Investigative Radiology Apr 2020The aims of this study were to investigate the feasibility of using a universal abdominal acquisition protocol on a photon-counting detector computed tomography (PCD-CT)...
OBJECTIVE
The aims of this study were to investigate the feasibility of using a universal abdominal acquisition protocol on a photon-counting detector computed tomography (PCD-CT) system and to compare its performance to that of single-energy (SE) and dual-energy (DE) CT using energy-integrating detectors (EIDs).
METHODS
Iodine inserts of various concentrations and sizes were embedded into different sizes of adult abdominal phantoms. Phantoms were scanned on a research PCD-CT and a clinical EID-CT with SE and DE modes. Virtual monoenergetic images (VMIs) were generated from PCD-CT and DE mode of EID-CT. For each image type and phantom size, contrast-to-noise ratio (CNR) was measured for each iodine insert and the area under the receiver operating characteristic curve (AUC) for iodine detectability was calculated using a channelized Hotelling observer. The optimal energy (in kiloelectrovolt) of VMIs was determined separately as the one with highest CNR and the one with the highest AUC. The PCD-CT VMIs at the optimal energy were then compared with DE VMIs and SE images in terms of CNR and AUC.
RESULTS
Virtual monoenergetic image at 50 keV had both the highest CNR and highest AUC for PCD-CT and DECT. For 1.0 mg I/mL iodine and 35 cm phantom, the CNRs of 50 keV VMIs from PCD-CT (2.01 ± 0.67) and DE (1.96 ± 0.52) were significantly higher (P < 0.001, Wilcoxon signed-rank test) than SE images (1.11 ± 0.35). The AUC of PCD-CT (0.98 ± 0.01) was comparable to SE (0.98 ± 0.01), and both were slightly lower than DE (0.99 ± 0.01, P < 0.01, Wilcoxon signed-rank test). A similar trend was observed for other phantom sizes and iodine concentrations.
CONCLUSIONS
Virtual monoenergetic images at a fixed energy from a universal acquisition protocol on PCD-CT demonstrated higher iodine CNR and comparable iodine detectability than SECT images, and similar performance compared with DE VMIs.
Topics: Adult; Feasibility Studies; Humans; Iodine; Observer Variation; Phantoms, Imaging; Photons; ROC Curve; Radiography, Abdominal; Signal-To-Noise Ratio; Tomography, X-Ray Computed
PubMed: 32049691
DOI: 10.1097/RLI.0000000000000634 -
Journal of Digital Imaging Aug 2019Assess the efficacy of deep convolutional neural networks (DCNNs) in detection of critical enteric feeding tube malpositions on radiographs. 5475 de-identified HIPAA...
Assess the efficacy of deep convolutional neural networks (DCNNs) in detection of critical enteric feeding tube malpositions on radiographs. 5475 de-identified HIPAA compliant frontal view chest and abdominal radiographs were obtained, consisting of 174 x-rays of bronchial insertions and 5301 non-critical radiographs, including normal course, normal chest, and normal abdominal x-rays. The ground-truth classification for enteric feeding tube placement was performed by two board-certified radiologists. Untrained and pretrained deep convolutional neural network models for Inception V3, ResNet50, and DenseNet 121 were each employed. The radiographs were fed into each deep convolutional neural network, which included untrained and pretrained models. The Tensorflow framework was used for Inception V3, ResNet50, and DenseNet. Images were split into training (4745), validation (630), and test (100). Both real-time and preprocessing image augmentation strategies were performed. Receiver operating characteristic (ROC) and area under the curve (AUC) on the test data were used to assess the models. Statistical differences among the AUCs were obtained. p < 0.05 was considered statistically significant. The pretrained Inception V3, which had an AUC of 0.87 (95 CI; 0.80-0.94), performed statistically significantly better (p < .001) than the untrained Inception V3, with an AUC of 0.60 (95 CI; 0.52-0.68). The pretrained Inception V3 also had the highest AUC overall, as compared with ResNet50 and DenseNet121, with AUC values ranging from 0.82 to 0.85. Each pretrained network outperformed its untrained counterpart. (p < 0.05). Deep learning demonstrates promise in differentiating critical vs. non-critical placement with an AUC of 0.87. Pretrained networks outperformed untrained ones in all cases. DCNNs may allow for more rapid identification and communication of critical feeding tube malpositions.
Topics: Deep Learning; Enteral Nutrition; Humans; Image Processing, Computer-Assisted; Medical Errors; Neural Networks, Computer; Radiography; Radiography, Abdominal; Radiography, Thoracic
PubMed: 31073816
DOI: 10.1007/s10278-019-00229-9 -
PloS One 2017Pancreatic pseudocysts arise mostly in patients with alcohol induced chronic pancreatitis causing various symptoms and complications. However, data on the optimal...
BACKGROUND
Pancreatic pseudocysts arise mostly in patients with alcohol induced chronic pancreatitis causing various symptoms and complications. However, data on the optimal management are rare. To address this problem, we analysed patients with pancreatic pseudocysts treated at our clinic retrospectively.
METHODS
We searched our clinical database for the diagnosis pancreatitis from 2004 till 2014, selected patients with pseudocysts larger than 10 mm and entered all relevant information in a database for statistical analysis.
RESULTS
In total, 129 patients with pancreatic pseudocysts were treated at our institution during the study period. Most patients suffered from alcohol induced chronic pancreatitis (43.4%; 56/129). Pseudocysts were more frequent in female than in male (2:1) and were mainly located in the pancreatic head (47.3%; 61/129). Local complications like obstructive jaundice were associated with the diameter of the cysts (AUC 0.697 in ROC-curve analysis). However, even cysts up to a diameter of 160 mm can regress spontaneously. Besides a lower re-intervention rate in surgically treated patients, endoscopic, percutaneous and surgical drainage are equally effective. Most treatment related complications occur in large pseudocysts located in the pancreatic head.
CONCLUSION
Conservative management of large pseudocysts is successful in many patients. Therefore, indication for treatment should be made carefully considering the presence and risk of local complications. Endoscopic and surgical drainage are equally effective.
Topics: Adult; Aged; Alcoholic Beverages; Alcoholism; Area Under Curve; Chronic Disease; Drainage; Endoscopy; Female; Follow-Up Studies; Humans; Male; Middle Aged; Pancreatic Pseudocyst; Pancreatitis, Chronic; ROC Curve; Radiography, Abdominal; Retrospective Studies; Sex Factors; Tomography, X-Ray Computed; Treatment Outcome
PubMed: 28877270
DOI: 10.1371/journal.pone.0184374 -
The British Journal of Radiology May 2018To evaluate the image quality, radiation dose, and renal safety of contrast medium (CM)-reduced abdominal-pelvic CT combining 80-kVp and sinogram-affirmed iterative...
Application of 80-kVp scan and raw data-based iterative reconstruction for reduced iodine load abdominal-pelvic CT in patients at risk of contrast-induced nephropathy referred for oncological assessment: effects on radiation dose, image quality and renal function.
OBJECTIVE
To evaluate the image quality, radiation dose, and renal safety of contrast medium (CM)-reduced abdominal-pelvic CT combining 80-kVp and sinogram-affirmed iterative reconstruction (SAFIRE) in patients with renal dysfunction for oncological assessment.
METHODS
We included 45 patients with renal dysfunction (estimated glomerular filtration rate <45 ml per min per 1.73 m) who underwent reduced-CM abdominal-pelvic CT (360 mgI kg, 80-kVp, SAFIRE) for oncological assessment. Another 45 patients without renal dysfunction (estimated glomerular filtration rate >60 ml per lmin per 1.73 m) who underwent standard oncological abdominal-pelvic CT (600 mgI kg, 120-kVp, filtered-back projection) were included as controls. CT attenuation, image noise, and contrast-to-noise ratio (CNR) were compared. Two observers performed subjective image analysis on a 4-point scale. Size-specific dose estimate and renal function 1-3 months after CT were measured.
RESULTS
The size-specific dose estimate and iodine load of 80-kVp protocol were 32 and 41%,, respectively, lower than of 120-kVp protocol (p < 0.01). CT attenuation and contrast-to-noise ratio of parenchymal organs and vessels in 80-kVp images were significantly better than those of 120-kVp images (p < 0.05). There were no significant differences in quantitative or qualitative image noise or subjective overall quality (p > 0.05). No significant kidney injury associated with CM administration was observed.
CONCLUSION
80-kVp abdominal-pelvic CT with SAFIRE yields diagnostic image quality in oncology patients with renal dysfunction under substantially reduced iodine and radiation dose without renal safety concerns. Advances in knowledge: Using 80-kVp and SAFIRE allows for 40% iodine load and 32% radiation dose reduction for abdominal-pelvic CT without compromising image quality and renal function in oncology patients at risk of contrast-induced nephropathy.
Topics: Abdomen; Adult; Aged; Aged, 80 and over; Algorithms; Contrast Media; Female; Humans; Image Processing, Computer-Assisted; Iodine; Kidney; Kidney Diseases; Male; Middle Aged; Pelvis; Radiation Dosage; Radiographic Image Enhancement; Radiography, Abdominal; Retrospective Studies; Tomography, X-Ray Computed
PubMed: 29470108
DOI: 10.1259/bjr.20170632 -
The American Journal of Case Reports Aug 2023BACKGROUND Ionizing radiation poses potential health risk to fetuses, including growth retardation, organ malformations, neurological effects, fetal death, and cancer....
BACKGROUND Ionizing radiation poses potential health risk to fetuses, including growth retardation, organ malformations, neurological effects, fetal death, and cancer. Therefore, pregnant women rarely undergo X-ray imaging, unless absolutely necessary. However, they can be inadvertently exposed to X-rays while undergoing an examination without being aware of their pregnancy. Given that the likelihood of a fetus appearing on an abdominal radiograph is low, physicians can be unfamiliar with the appearance of a fetus on such images. If a fetus incidentally appears on an abdominal radiograph, the clinician can encounter difficulties in identifying the fetus, potentially leading to unexpected harm during subsequent imaging procedures. CASE REPORT A 41-year-old woman presented with symptoms of postprandial abdominal pain, abdominal fullness, and urinary frequency. Abdominal radiography revealed a large mass with calcifications in the pelvis and lower abdomen, raising suspicion of a large pelvic tumor, such as a teratoma. However, subsequent ultrasound unexpectedly revealed that the woman was actually 6 months pregnant. The presumed tumor was an enlarged uterus, and the presumed calcifications were the fetus's bones. Before X-ray, the woman had denied being pregnant, mistakenly attributing her condition to excess weight and irregular menstrual cycles. Fortunately, the use of ultrasound instead of computed tomography prevented radiation exposure to the fetus, and the baby was delivered in a healthy state at full term. CONCLUSIONS To avoid unintended harm to fetuses, clinicians should consider the possibility of pregnancy when evaluating a pelvic mass in women of childbearing age. To aid clinicians in accurately identifying fetuses on abdominal radiography and thereby reduce the likelihood of misdiagnosis, we propose the "circled delta sign" and the "reversed circled delta sign".
Topics: Female; Pregnancy; Infant; Humans; Adult; Radiography, Abdominal; Fetus; Tomography, X-Ray Computed; Abdominal Pain
PubMed: 37621077
DOI: 10.12659/AJCR.940689 -
Physics in Medicine and Biology Apr 2020Deformable image registration (DIR) of 4D-CT images is important in multiple radiation therapy applications including motion tracking of soft tissue or fiducial markers,...
Deformable image registration (DIR) of 4D-CT images is important in multiple radiation therapy applications including motion tracking of soft tissue or fiducial markers, target definition, image fusion, dose accumulation and treatment response evaluations. It is very challenging to accurately and quickly register 4D-CT abdominal images due to its large appearance variances and bulky sizes. In this study, we proposed an accurate and fast multi-scale DIR network (MS-DIRNet) for abdominal 4D-CT registration. MS-DIRNet consists of a global network (GlobalNet) and local network (LocalNet). GlobalNet was trained using down-sampled whole image volumes while LocalNet was trained using sampled image patches. MS-DIRNet consists of a generator and a discriminator. The generator was trained to directly predict a deformation vector field (DVF) based on the moving and target images. The generator was implemented using convolutional neural networks with multiple attention gates. The discriminator was trained to differentiate the deformed images from the target images to provide additional DVF regularization. The loss function of MS-DIRNet includes three parts which are image similarity loss, adversarial loss and DVF regularization loss. The MS-DIRNet was trained in a completely unsupervised manner meaning that ground truth DVFs are not needed. Different from traditional DIRs that calculate DVF iteratively, MS-DIRNet is able to calculate the final DVF in a single forward prediction which could significantly expedite the DIR process. The MS-DIRNet was trained and tested on 25 patients' 4D-CT datasets using five-fold cross validation. For registration accuracy evaluation, target registration errors (TREs) of MS-DIRNet were compared to clinically used software. Our results showed that the MS-DIRNet with an average TRE of 1.2 ± 0.8 mm outperformed the commercial software with an average TRE of 2.5 ± 0.8 mm in 4D-CT abdominal DIR, demonstrating the superior performance of our method in fiducial marker tracking and overall soft tissue alignment.
Topics: Algorithms; Deep Learning; Four-Dimensional Computed Tomography; Humans; Image Processing, Computer-Assisted; Neoplasms; Neural Networks, Computer; Radiography, Abdominal; Radiotherapy Planning, Computer-Assisted; Retrospective Studies
PubMed: 32097902
DOI: 10.1088/1361-6560/ab79c4