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1.
Tomography ; 10(5): 643-653, 2024 Apr 24.
Article En | MEDLINE | ID: mdl-38787009

Objective: This study investigates the correlation between patient body metrics and radiation dose in abdominopelvic CT scans, aiming to identify significant predictors of radiation exposure. Methods: Employing a cross-sectional analysis of patient data, including BMI, abdominal fat, waist, abdomen, and hip circumference, we analyzed their relationship with the following dose metrics: the CTDIvol, DLP, and SSDE. Results: Results from the analysis of various body measurements revealed that BMI, abdominal fat, and waist circumference are strongly correlated with increased radiation doses. Notably, the SSDE, as a more patient-centric dose metric, showed significant positive correlations, especially with waist circumference, suggesting its potential as a key predictor for optimizing radiation doses. Conclusions: The findings suggest that incorporating patient-specific body metrics into CT dosimetry could enhance personalized care and radiation safety. Conclusively, this study highlights the necessity for tailored imaging protocols based on individual body metrics to optimize radiation exposure, encouraging further research into predictive models and the integration of these metrics into clinical practice for improved patient management.


Abdominal Fat , Body Mass Index , Pelvis , Radiation Dosage , Tomography, X-Ray Computed , Waist Circumference , Humans , Tomography, X-Ray Computed/methods , Male , Female , Cross-Sectional Studies , Middle Aged , Pelvis/diagnostic imaging , Adult , Abdominal Fat/diagnostic imaging , Aged , Radiography, Abdominal/methods , Retrospective Studies
2.
Eur J Radiol ; 175: 111447, 2024 Jun.
Article En | MEDLINE | ID: mdl-38677039

OBJECTIVES: Robustness of radiomic features in physiological tissue is an important prerequisite for quantitative analysis of tumor biology and response assessment. In contrast to previous studies which focused on different tumors with mostly short scan-re-scan intervals, this study aimed to evaluate the robustness of radiomic features in cancer-free patients and over a clinically encountered inter-scan interval. MATERIALS AND METHODS: Patients without visible tumor burden who underwent at least two portal-venous phase dual energy CT examinations of the abdomen between May 2016 and January 2020 were included, while macroscopic tumor burden was excluded based upon follow-up imaging for all patients (≥3 months). Further, patients were excluded if no follow-up imaging was available, or if the CT protocol showed deviations between repeated examinations. Circular regions of interest were placed and proofread by two board-certified radiologists (4 years and 5 years experience) within the liver (segments 3 and 6), the psoas muscle (left and right), the pancreatic head, and the spleen to obtain radiomic features from normal-appearing organ parenchyma using PyRadiomics. Radiomic feature robustness was tested using the concordance correlation coefficient with a threshold of 0.75 considered indicative for deeming a feature robust. RESULTS: In total, 160 patients with 480 repeated abdominal CT examinations (range: 2-4 per patient) were retrospectively included in this single-center, IRB-approved study. Considering all organs and feature categories, only 4.58 % (25/546) of all features were robust with the highest rate being found in the first order feature category (20.37 %, 22/108). Other feature categories (grey level co-occurrence matrix, grey level dependence matrix, grey level run length matrix, grey level size zone matrix, and neighborhood gray-tone difference matrix) yielded an overall low percentage of robust features (range: 0.00 %-1.19 %). A subgroup analysis revealed the reconstructed field of view and the X-ray tube current as determinants of feature robustness (significant differences in subgroups for all organs, p < 0.001) as well as the size of the region of interest (no significant difference for the pancreatic head with p = 0.135, significant difference with p < 0.001 for all other organs). CONCLUSION: Radiomic feature robustness obtained from cancer-free subjects with repeated examinations using a consistent protocol and CT scanner was limited, with first order features yielding the highest proportion of robust features.


Radiography, Dual-Energy Scanned Projection , Tomography, X-Ray Computed , Humans , Male , Female , Tomography, X-Ray Computed/methods , Middle Aged , Radiography, Dual-Energy Scanned Projection/methods , Aged , Adult , Retrospective Studies , Pancreas/diagnostic imaging , Liver/diagnostic imaging , Radiography, Abdominal/methods , Aged, 80 and over , Spleen/diagnostic imaging , Parenchymal Tissue/diagnostic imaging , Psoas Muscles/diagnostic imaging , Radiomics
3.
Biomed Phys Eng Express ; 10(3)2024 Apr 26.
Article En | MEDLINE | ID: mdl-38631317

Introduction. The currently available dosimetry techniques in computed tomography can be inaccurate which overestimate the absorbed dose. Therefore, we aimed to provide an automated and fast methodology to more accurately calculate the SSDE usingDwobtained by using CNN from thorax and abdominal CT study images.Methods. The SSDE was determined from the 200 records files. For that purpose, patients' size was measured in two ways: (a) by developing an algorithm following the AAPM Report No. 204 methodology; and (b) using a CNN according to AAPM Report No. 220.Results. The patient's size measured by the in-house software in the region of thorax and abdomen was 27.63 ± 3.23 cm and 28.66 ± 3.37 cm, while CNN was 18.90 ± 2.6 cm and 21.77 ± 2.45 cm. The SSDE in thorax according to 204 and 220 reports were 17.26 ± 2.81 mGy and 23.70 ± 2.96 mGy for women and 17.08 ± 2.09 mGy and 23.47 ± 2.34 mGy for men. In abdomen was 18.54 ± 2.25 mGy and 23.40 ± 1.88 mGy in women and 18.37 ± 2.31 mGy and 23.84 ± 2.36 mGy in men.Conclusions. Implementing CNN-based automated methodologies can contribute to fast and accurate dose calculations, thereby improving patient-specific radiation safety in clinical practice.


Algorithms , Radiation Dosage , Tomography, X-Ray Computed , Humans , Tomography, X-Ray Computed/methods , Male , Female , Body Size , Neural Networks, Computer , Software , Automation , Thorax/diagnostic imaging , Adult , Abdomen/diagnostic imaging , Radiometry/methods , Radiography, Thoracic/methods , Middle Aged , Image Processing, Computer-Assisted/methods , Radiography, Abdominal/methods , Aged
4.
Abdom Radiol (NY) ; 49(5): 1762-1770, 2024 May.
Article En | MEDLINE | ID: mdl-38546824

PURPOSE: Photon-counting detector CT (PCD CT) is a promising technology for abdominal imaging due to its ability to provide high spatial and contrast resolution images with reduced patient radiation exposure. However, there is currently no consensus regarding the optimal imaging protocols for PCD CT. This article aims to present the PCD CT abdominal imaging protocols used by two tertiary care academic centers in the United States. METHODS: A review of PCD CT abdominal imaging protocols was conducted by two abdominal radiologists at different academic institutions. Protocols were compared in terms of acquisition parameters and reconstruction settings. Both imaging centers independently selected similar protocols for PCD CT abdominal imaging, using QuantumPlus mode. RESULTS: There were some differences in the use of reconstruction kernels and iterative reconstruction levels, however the individual combination at each site resulted in similar image impressions. Overall, the imaging protocols used by both centers provide high-quality images with low radiation exposure. CONCLUSION: These findings provide valuable insights into the development of standardized protocols for PCD CT abdominal imaging, which can help to ensure consistent as well as high-quality imaging across different institutions and allow for future multicenter research collaborations.


Radiation Dosage , Radiography, Abdominal , Tomography, X-Ray Computed , Humans , Tomography, X-Ray Computed/methods , Radiography, Abdominal/methods , Photons , Radiographic Image Interpretation, Computer-Assisted/methods , Consensus , United States , Academic Medical Centers
5.
J Comput Assist Tomogr ; 48(3): 406-414, 2024.
Article En | MEDLINE | ID: mdl-38271539

OBJECTIVE: Prostate cancer and interstitial lung abnormality (ILA) share similar risk factor, which is men and older age. The purpose of this study was to investigate the prevalence of pretreatment ILA among prostate cancer patients who underwent abdominal computed tomography (CT) within 1 year at their first visit to the urology department. In addition, we aimed to assess the association between pretreatment ILA and long-term survival in prostate cancer patients. METHODS: This study was conducted in patients who had a first visit for prostate cancer at urology department between 2005 and 2016 and underwent an abdominal CT within 1 year. A thoracic radiologist evaluated the presence of ILA through inspecting the lung base scanned on an abdominal CT. The association between pretreatment ILA and survival was assessed using Kaplan-Meier analysis with log-rank test. Specific survival rates at 12, 36, and 60 months according to the presence of ILA were evaluated using z -test. Cox regression analysis was used to assess the risk factors of mortality. RESULTS: A total of 173 patients were included (mean age, 70.23 ± 7.98 years). Pretreatment ILA was observed in 10.4% of patients. Patients with ILA were more likely to be older and current smokers. Pretreatment ILA was associated with poor survival ( P < 0.001). Age ≥70 years (hazards ratio [HR], 1.98; 95% confidence interval [CI], 1.24-3.16; P = 0.004), metastatic stage (HR, 2.26; 95% CI, 1.36-3.74; P = 0.002), and ILA (HR, 1.96; 95% CI, 1.06-3.60; P = 0.031) were the independent risk factors of mortality. An ILA (HR, 3.94; 95% CI, 1.78-8.72; P = 0.001) was the only independent risk factor of mortality in localized stage prostate cancer patients. CONCLUSIONS: This study provides important insights into the unexplored effect of pretreatment ILA in prostate cancer patients. Pretreatment ILAs were observed considerably in the lung bases scanned on the abdominal CT scans among prostate cancer patients. Furthermore, pretreatment ILAs were the risk factor of mortality. Therefore, lung bases should be routinely inspected in the abdominal CT scans of prostate cancer patients. This result may help clinicians in establishing personalized management strategy of prostate cancer patients.


Lung Diseases, Interstitial , Prostatic Neoplasms , Tomography, X-Ray Computed , Humans , Male , Prostatic Neoplasms/diagnostic imaging , Aged , Lung Diseases, Interstitial/diagnostic imaging , Tomography, X-Ray Computed/methods , Middle Aged , Retrospective Studies , Risk Factors , Radiography, Abdominal/methods , Lung/diagnostic imaging
6.
Am J Emerg Med ; 78: 18-21, 2024 Apr.
Article En | MEDLINE | ID: mdl-38181541

OBJECTIVES: Ultrasound is the criterion standard imaging modality for the diagnosis of intussusception. However, to our knowledge the utility of abdominal radiographs to concurrently screen for pneumoperitoneum or other abdominal pathology that could have a similar presentation has not been studied. Our institutional protocol requires the performance of AP supine and left lateral decubitus views of the abdomen prior to ultrasound evaluation for intussusception, providing an opportunity to examine the yield of abdominal radiographs in this setting. Our primary objective was to determine the rate of pneumoperitoneum on screening abdominal radiographs in children undergoing evaluation for intussusception. Our secondary objective was to determine the rate that other clinically significant pathology is found on these screening abdominal radiographs. METHODS: We performed a retrospective chart review of all patients under 6 years of age who had any imaging ordered in our large urban pediatric emergency department to evaluate for suspected intussusception during the calendar years 2018-2020. RESULTS: 1115 patient encounters met our inclusion criteria. Among 1090 who had screening abdominal radiographs, 82 (8%) had findings concerning for intussusception. Of those not concerning for intussusception, 635 (58%) were read as normal, 263 (24%) showed moderate to large stool burden, 107 (10%) showed generalized bowel distention, and 22 (2%) showed abnormal gastric distention. Individually the remainder of all other findings compromised <1% of encounters and included radiopaque foreign body (8), intraabdominal calcification (4), pneumonia/effusion (3), pneumatosis intestinalis, abdominal mass (2), diaphragmatic hernia (1), rib fracture (1), appendicolith (1), feeding tube malposition (1), and bowel wall thickening (1). In one encounter the patient had a bowel perforation with pneumoperitoneum present secondary to ingestion of multiple magnets. CONCLUSIONS: Our study indicates that radiograph-detected pneumoperitoneum is rare in children with suspected intussusception. Constipation is the most common abnormal finding on screening radiographs. Other findings occur in approximately 15% of total cases, some of which require further workup.


Intussusception , Pneumoperitoneum , Child , Humans , Intussusception/diagnostic imaging , Pneumoperitoneum/diagnostic imaging , Retrospective Studies , Sensitivity and Specificity , Radiography, Abdominal/methods , Abdomen
7.
Clin Toxicol (Phila) ; 61(4): 312-314, 2023 04.
Article En | MEDLINE | ID: mdl-37017708

INTRODUCTION: Diagnosis of body packing based on the misinterpretation of imaging is rare. CASE REPORT: An unaccompanied 55-year-old woman presented with uncontrolled vomiting in the airport transit area. An abdominal radiograph and computed tomography scan revealed multiple radiopaque foreign bodies in the colon. History was unobtainable due to the language barrier. The patient was referred to our institution as a body packer who required surgical extraction of the packets. In the absence of symptoms, she was managed conservatively with antiemetic drugs and whole bowel irrigation. The final diagnosis was radiopaque pharmacobezoars caused by an over-the-counter barium-containing anticancer medication in the setting of severe hypokalemia-associated paralytic ileus following post-chemotherapy vomiting. After the correction of her potassium concentration, the patient was discharged and resumed her trip. CONCLUSION: Clinicians should be warned that pharmacobezoars might be mistaken for drug packets on abdominal imaging leading to body packing misdiagnosis.


Body Packing , Foreign Bodies , Humans , Female , Middle Aged , Radiography, Abdominal/methods , Foreign Bodies/diagnosis , Vomiting , Diagnostic Errors
8.
BMC Pediatr ; 23(1): 134, 2023 03 24.
Article En | MEDLINE | ID: mdl-36959616

BACKGROUND: To examine the use of abdominal ultrasound (AUS) as a diagnostic adjunct in the diagnosis of necrotizing enterocolitis (NEC) in cases where abdominal radiography (AXR) is equivocal in order to reduce unnecessary antibiotic use in neonates. METHODS: Retrospective study (2017-2019) of infants undergoing NEC evaluation with equivocal AXR findings (n = 54). Paired AXR and AUS were reviewed with respect to presence or absence of pneumatosis. Concordance of AUS findings with decision to treat for NEC was evaluated. RESULTS: Among 54 infants where AXR was equivocal, AUS demonstrated presence of pneumatosis in 22 patients (41%), absence of pneumatosis in 31 patients (57%), and was equivocal in 1 patient. All patients with pneumatosis on AUS were treated for NEC. Of 31 patients without pneumatosis on AUS, 25 patients (78%) were not treated for NEC. Patients without pneumatosis on AUS received a significantly shorter mean duration of antibiotics compared to those with pneumatosis (3.3 days (+/- 4.8 days) vs 12.4 days (+/- 4.7 days)); p < 0.001). Of those patients not treated, none required treatment within 1 week following negative AUS. CONCLUSION: AUS is a valuable tool for evaluating the presence or absence of pneumatosis in the setting of equivocal AXR. Absence of pneumatosis on AUS informs clinical decision making and reduces unnecessary treatment and antibiotic usage.


Enterocolitis, Necrotizing , Infant, Newborn, Diseases , Infant , Infant, Newborn , Humans , Enterocolitis, Necrotizing/diagnosis , Retrospective Studies , Radiography, Abdominal/methods , Infant, Newborn, Diseases/diagnosis , Ultrasonography/methods
9.
Clin Imaging ; 93: 52-59, 2023 Jan.
Article En | MEDLINE | ID: mdl-36375364

OBJECTIVES: To provide our oncology-specific adult abdominal-pelvic CT reference levels for image noise and radiation dose from a high-volume, oncologic, tertiary referral center. METHODS: The portal venous phase abdomen-pelvis acquisition was assessed for image noise and radiation dose in 13,320 contrast-enhanced CT examinations. Patient size (effective diameter) and radiation dose (CTDIvol) were recorded using a commercial software system, and image noise (Global Noise metric) was quantified using a custom processing system. The reference level and range for dose and noise were calculated for the full dataset, and for examinations grouped by CT scanner model. Dose and noise reference levels were also calculated for exams grouped by five different patient size categories. RESULTS: The noise reference level was 11.25 HU with a reference range of 10.25-12.25 HU. The dose reference level at a median effective diameter of 30.7 cm was 26.7 mGy with a reference range of 19.6-37.0 mGy. Dose increased with patient size; however, image noise remained approximately constant within the noise reference range. The doses were 2.1-2.5 times than the doses in the ACR DIR registry for corresponding patient sizes. The image noise was 0.63-0.75 times the previously published reference level in abdominal-pelvic CT examinations. CONCLUSIONS: Our oncology-specific abdominal-pelvic CT dose reference levels are higher than in the ACR dose index registry and our oncology-specific image noise reference levels are lower than previously proposed image noise reference levels. ADVANCES IN KNOWLEDGE: This study reports reference image noise and radiation dose levels appropriate for the indication of abdomen-pelvis CT examination for cancer diagnosis and staging. The difference in these reference levels from non-oncology-specific CT examinations highlight a need for indication-specific, dose index and image quality reference registries.


Pelvis , Radiography, Abdominal , Adult , Humans , Radiography, Abdominal/methods , Radiation Dosage , Pelvis/diagnostic imaging , Abdomen/diagnostic imaging , Tomography, X-Ray Computed/methods
10.
Radiologie (Heidelb) ; 62(6): 523-534, 2022 Jun.
Article De | MEDLINE | ID: mdl-35925057

Due to the complexity of pelvic floor dysfunctions and the frequent interdisciplinary findings, dynamic magnetic resonance imaging (MRI) can provide valuable (additional) information for the clinical examination in other disciplines through a comprehensive morphological and functional representation of the pelvic floor. It has therefore largely replaced conventional defecography under fluoroscopy in clinical practice. In order to increase the effectiveness and communication between radiology and the other specialist disciplines, recommendations for the standardized implementation and results of dynamic MRI were published by the European Society for Urogenital radiology (ESUR) in 2016 and based on these the Society for Abdominal Radiology (SAR) published simplified recommendations in 2019 for routine clinical use.


Defecography , Pelvic Floor Disorders , Defecography/methods , Female , Humans , Magnetic Resonance Imaging/methods , Pelvic Floor/diagnostic imaging , Pelvic Floor Disorders/diagnostic imaging , Radiography, Abdominal/methods
11.
Clin Imaging ; 90: 32-38, 2022 Oct.
Article En | MEDLINE | ID: mdl-35914341

Acute abdominal pain is a common cause of ED visits and often requires imaging to identify a specific diagnosis. Prompt and appropriate imaging plays a crucial role in patient management and leads to improved patient outcomes, decreased hospital stay, and improved ED workflow. There are many cases of abdominal pain in the ED with delayed diagnosis and management secondary to a combination of institutional policies and knowledge deficits in current imaging guidelines. Inappropriate use of abdominal radiographs, use of oral contrast for CT abdomen and pelvis, and concern for iodinated contrast-induced acute kidney injury are three of the more commonly encountered roadblocks to prompt imaging diagnosis of abdominal pain. The purpose of this review is to discuss why these potential causes of delayed diagnosis occur and how radiologists can help improve both imaging and ED workflow by utilizing the most up-to-date imaging guidelines such the American College of Radiology (ACR) Appropriateness Criteria and ACR Manual on Contrast Media to assist clinicians working in the emergency setting.


Abdominal Pain , Emergency Service, Hospital , Abdominal Pain/diagnostic imaging , Abdominal Pain/etiology , Contrast Media/adverse effects , Humans , Radiography, Abdominal/methods , Tomography, X-Ray Computed/methods
12.
J Chin Med Assoc ; 85(6): 709-716, 2022 06 01.
Article En | MEDLINE | ID: mdl-35316248

BACKGROUND: Plain abdominal radiography including supine and erect abdominal radiographs (SAR and EAR) is a frequently used image modality for preliminary evaluation of acute abdomen. We aimed to explore which one of the SAR or EAR has a higher diagnostic value in overall diagnosis of acute abdomen, including their respective advantages over each other for the various underlying diseases. METHODS: We retrospectively analyzed the imaging findings of plain abdominal radiography of patients with acute abdomen who received abdominal computed tomography (CT) within 24 hours at the emergency department of a medical center in northern Taiwan between October 2019 and February 2020. Final diagnosis was made by CT reports and clinical data. The relevance between the imaging findings and clinical diagnosis in the groups of SAR and EAR were compared. RESULTS: A total of 1009 cases with acute abdomen were included, of which 341 (33.8%) underwent EAR and 668 (66.2%) underwent SAR. Among them, 820 cases had final diagnosis confirmed by CT and clinical data. In comparison of the diagnostic relevance of SAR and EAR, there were no significant difference in the overall acute abdomen, but EAR showed a better diagnostic relevance in cases with bowel obstruction than SAR did (100% vs 87.2%, p < 0.05). No statistical difference in other abdominal diseases. CONCLUSION: There is no significant difference between SAR and EAR in evaluation of overall acute abdomen. However, EARs has a diagnostic advantage over SAR for evaluation of suspected bowel obstruction.


Abdomen, Acute , Intestinal Obstruction , Abdomen, Acute/diagnostic imaging , Decision Making , Humans , Radiography, Abdominal/methods , Retrospective Studies
13.
Radiology ; 302(1): 118-126, 2022 01.
Article En | MEDLINE | ID: mdl-34636635

Background Assessment of the biliary origin of acute pancreatitis (AP) is crucial because it affects patient treatment to avoid recurrence. Although CT is systematically performed to determine severity in AP, its usefulness in assessing AP biliary origin has not been evaluated. Purpose To assess abdominal CT features associated with acute biliary pancreatitis (ABP) and to evaluate the predictive value of a combination of CT and clinical data for determining a biliary origin in a first episode of AP. Materials and Methods From December 2014 to May 2019, all consecutive patients who presented with a first episode of AP and with at least 6 months of follow-up were retrospectively reviewed. Evidence of gallstones was mandatory for a clinical diagnosis of ABP. Abdominal CT images were reviewed by two abdominal radiologists. Univariable and multivariable statistical analyses were performed, and a nomogram was constructed on the basis of the combination of clinical and CT features. This nomogram was validated in a further independent internal cohort of patients. Results A total of 271 patients (mean age ± standard deviation, 56 years ± 20; 160 men) were evaluated. Of these, 170 (63%) had ABP. At multivariable analysis, age (odds ratio [OR], 1.06; 95% CI: 1.03, 1.09; P < .001), alanine aminotransferase level (OR, 1.00; 95% CI: 1.00, 1.01; P = .009), gallbladder gallstone (OR, 15.59; 95% CI: 4.61, 68.62; P < .001), choledochal ring sign (OR, 5.73; 95% CI: 2.11, 17.05; P < .001), liver spontaneous attenuation (OR, 1.07; 95% CI: 1.04, 1.11; P < .001), and duodenal thickening (OR, 0.17; 95% CI: 0.03, 0.61; P = .01) were independently associated with ABP. The matching nomogram combining both clinical and CT features displayed an area under the curve of 0.94 (95% CI: 0.91, 0.97) in the study sample (n = 271) and 0.91 (95% CI: 0.84, 0.99) in the validation cohort (n = 51). Conclusion Abdominal CT provided useful features for diagnosis of acute biliary pancreatitis (ABP). Combining CT and clinical features in a nomogram showed good diagnostic performance for early diagnosis of ABP. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Chang in this issue.


Biliary Tract/diagnostic imaging , Pancreatitis/diagnostic imaging , Radiography, Abdominal/methods , Tomography, X-Ray Computed/methods , Female , Humans , Male , Middle Aged , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies
14.
Radiography (Lond) ; 28(1): 107-114, 2022 02.
Article En | MEDLINE | ID: mdl-34544645

INTRODUCTION: This study aims to identify optimal exposure parameters, delivering the lowest radiation dose while maintaining images of diagnostic quality for the antero-posterior (AP) abdomen x-ray projection in large patients with an AP abdominal diameter of >22.3 cm. METHODOLOGY: The study was composed of two phases. In phase 1, an anthropomorphic phantom (20 cm AP abdominal diameter) was repetitively radiographed while adding 3 layers (5 cm thick each) of fat onto the phantom reaching a maximum AP abdominal diameter of 35 cm. For every 5 cm thickness, images were taken at 10 kVp (kilovoltage peak) intervals, starting from 80 kVp as the standard protocol currently in use at the local medical imaging department, to 120 kVp in combination with the use of automatic exposure control (AEC). The dose area product (DAP), milliampere-second (mAs) delivered by the AEC, and measurements to calculate the signal to noise ratio (SNR) and contrast to noise ratio (CNR) were recorded. Phase 2 included image quality evaluation of the resultant images by radiographers and radiologists through absolute visual grading analysis (VGA). The resultant VGA scores were analysed using visual grading characteristics (VGC) curves. RESULTS: The optimal kVp setting for AP abdominal diameters at: 20 cm, 25 cm and 30 cm was found to be 110 kVp increased from 80 kVp as the standard protocol (with a 56.5% decrease in DAP and 76.2% in mAs, a 54.2% decrease in DAP and 76.2% decrease in mAs and a 29.2% decrease in DAP and 59.7% decrease in mAs, respectively). The optimal kVp setting for AP abdominal diameter at 35 cm was found to be 120 kVp increased from 80 kvp as the standard protocol (with a 50.7% decrease in DAP and 73.4% decrease in mAs). All this was achieved while maintaining images of diagnostic quality. CONCLUSION: Tailoring the exposure parameters for large patients in radiography of the abdomen results in a significant reductions in DAP which correlates to lower patient doses while still maintaining diagnostic image quality. IMPLICATIONS FOR CLINICAL PRACTICE: This research study and resultant parameters may help guide clinical departments to optimise AP abdomen radiographic exposures for large patients in the clinical setting.


Abdomen , Radiography, Abdominal , Abdomen/diagnostic imaging , Humans , Phantoms, Imaging , Radiation Dosage , Radiography, Abdominal/methods , Signal-To-Noise Ratio
16.
Br J Radiol ; 95(1130): 20210791, 2022 Feb 01.
Article En | MEDLINE | ID: mdl-34826227

With optimized technique, the water-soluble contrast challenge is effective at triaging patients for operative vs non-operative management of suspected small bowel obstruction. Standardized study structure and interpretation guidelines aid in clinical efficacy and ease of use. Many tips and tricks exist regarding technique and interpretation, and their understanding may assist the interpreting radiologist. In the future, a CT-based water-soluble contrast challenge, utilizing oral contrast given as part of the initial CT examination, might allow for a more streamlined algorithm and provide more rapid results.


Contrast Media/administration & dosage , Intestinal Obstruction/diagnostic imaging , Intestine, Small/diagnostic imaging , Administration, Oral , Adult , Aged , Aged, 80 and over , Algorithms , Colon/diagnostic imaging , Conservative Treatment , Diatrizoate Meglumine/administration & dosage , Gastrointestinal Transit , Humans , Intestinal Obstruction/etiology , Intestinal Obstruction/therapy , Intubation, Gastrointestinal/methods , Iohexol/administration & dosage , Middle Aged , Radiography, Abdominal/methods , Treatment Outcome , Triage/methods
17.
Sci Rep ; 11(1): 21790, 2021 11 08.
Article En | MEDLINE | ID: mdl-34750427

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.


Angiography, Digital Subtraction/methods , Leg/diagnostic imaging , Aged , Aged, 80 and over , Female , Humans , Leg/blood supply , Male , Middle Aged , Peripheral Vascular Diseases/diagnostic imaging , Prospective Studies , Radiation Dosage , Radiography, Abdominal/methods , Signal-To-Noise Ratio
18.
Radiol Clin North Am ; 59(6): 987-1002, 2021 Nov.
Article En | MEDLINE | ID: mdl-34689882

Organ segmentation, chest radiograph classification, and lung and liver nodule detections are some of the popular artificial intelligence (AI) tasks in chest and abdominal radiology due to the wide availability of public datasets. AI algorithms have achieved performance comparable to humans in less time for several organ segmentation tasks, and some lesion detection and classification tasks. This article introduces the current published articles of AI applied to chest and abdominal radiology, including organ segmentation, lesion detection, classification, and predicting prognosis.


Artificial Intelligence , Gastrointestinal Diseases/diagnostic imaging , Image Interpretation, Computer-Assisted/methods , Radiography, Abdominal/methods , Radiography, Thoracic/methods , Thoracic Diseases/diagnostic imaging , Humans
19.
Am J Emerg Med ; 50: 449-454, 2021 Dec.
Article En | MEDLINE | ID: mdl-34492590

OBJECTIVE: Physicians frequently use ultrasound to assess hydronephrosis in patients with suspected renal colic, but ultrasound has limited diagnostic sensitivity and rarely clarifies stone size or location. Consequently, up to 80% of emergency department (ED) renal colic patients undergo confirmatory CT imaging. Our goal was to estimate x-ray sensitivity for urinary stones and determine whether x-ray substantially improves stone detection (sensitivity) compared to hydronephrosis assessment alone. METHODS: We reviewed imaging reports from all renal colic patients who underwent x-ray and CT at four EDs. For each patient, we documented stone size, location and hydronephrosis severity on CT and whether stones were identified on x-ray. We considered moderate and severe hydronephrosis (MS-Hydro) as significant positive findings, then calculated the sensitivity (detection rate) of MS-Hydro and x-ray for large stones ≥5 mm and for stones likely to require intervention (all ureteral stones >7 mm and proximal or middle stones >5 mm). We then tested a diagnostic algorithm adding x-ray to hydronephrosis assessment. RESULTS: Among 1026 patients with 1527 stones, MS-Hydro sensitivity was 39% for large stones and 60% for interventional stones. X-ray sensitivity was 46% for large stones and 52% for interventional stones. Adding x-ray to hydronephrosis assessment increased sensitivity in all stone categories, specifically from 39% to 68% for large stones (gain = 29%; 95%CI, 23% to 35%) and from 60% to 82% for interventional stones (gain = 22%; 95%CI, 13% to 30%). Because CT and ultrasound show strong agreement for MS-Hydro identification, physicians who depend on ultrasound-based hydronephrosis assessment could achieve similar gains by adding x-ray. CONCLUSIONS: Adding x-ray to hydronephrosis assessment substantially improves diagnostic sensitivity, enabling the detection of nearly 70% of large stones and over 80% of interventional stones. This level of sensitivity may be sufficient to reassure physicians about a renal colic diagnosis without CT imaging for many patients.


Hydronephrosis/diagnostic imaging , Radiography, Abdominal/methods , Renal Colic/diagnostic imaging , Urolithiasis/diagnostic imaging , Algorithms , Emergency Service, Hospital , Female , Humans , Male , Middle Aged , Retrospective Studies , Sensitivity and Specificity , Tomography, X-Ray Computed
20.
Am J Gastroenterol ; 116(12): 2367-2373, 2021 12 01.
Article En | MEDLINE | ID: mdl-34506328

INTRODUCTION: A gastrostomy is generally performed in patients who are unable to maintain volitional intake of food. We compared outcomes of percutaneous endoscopic gastrostomy (PEG) and interventional radiologist-guided gastrostomy (IRG) using an integrated nationwide database. METHODS: Using the VA Informatics and Computing Infrastructure database, patients who underwent PEG or IRG from 2011 through 2021 were selected using Current Procedural Terminology and International Classification of Diseases codes. The primary outcome was the comparative incidence of adverse events between PEG and IRG. Secondary outcomes included all-cause mortality. Comorbidities were identified using International Classification of Diseases codes, and adjusted odds ratio (OR) for adverse events were calculated using multivariate logistic regression analysis. RESULTS: A total of 23,566 (70.7 ± 10.2 years) patients underwent PEG and 9,715 (69.6 ± 9.7 years) underwent IRG. Selected frequent indications for PEG vs IRG were as follows: stroke, 6.8% vs 5.3%, P < 0.01; aspiration pneumonia, 10.9% vs 6.8%, P < 0.001; feeding difficulties, 9.8% vs 6.3%, P < 0.01; and upper aerodigestive tract malignancies 58.8% vs 79.8%, P < 0.01. Across all subtypes of malignancies of the head and neck and foregut, the proportion of patients undergoing IRG was greater than those undergoing PEG (P < 0.001). The all-cause 30-day mortality and overall incidence of adverse events were significantly lower for PEG compared with those for IRG (PEG vs IRG): all-cause 30-day mortality, 9.35% vs 10.3% (OR 0.80; 95% confidence interval [CI] 0.74-0.87; P < 0.01); perforation of the colon, 0.12% vs 0.24% (OR 0.50; 95% CI 0.29-0.86; P = 0.04); peritonitis, 1.9% vs 2.7% (OR 0.68; 95% CI 0.58-0.79; P < 0.01); and hemorrhage 1.6% vs 1% (OR 1.47; 95% CI 1.18-1.83; P < 0.01). DISCUSSION: In a large nationwide database of more than 33,000 gastrostomy procedures, PEG was associated with a lower incidence of adverse outcomes and the 30-day mortality than IRG.


Enteral Nutrition/methods , Gastroscopy/methods , Gastrostomy/methods , Radiography, Abdominal/methods , United States Department of Veterans Affairs/statistics & numerical data , Veterans , Aged , Databases, Factual , Female , Follow-Up Studies , Humans , Male , Retrospective Studies , Risk Factors , United States
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