CT of appendicoliths in adult appendicitis: clinical significance and characteristics of overlooked cases.

OBJECTIVES: Accurate computed tomography (CT) identification of appendicoliths in adults with acute appendicitis is crucial as it may preclude nonoperative management due to high risk of failure and complications. This investigation aimed to identify the significance of appendicoliths in acute appendicitis and to evaluate the performance of portovenous-phase (PVP) CT and the consequences of overlooked appendicoliths. METHODS: CT examinations of 324 consecutive patients (mean age 51.9 years, 112 men) with pathologically confirmed acute appendicitis were retrospectively included. Two radiologists independently reviewed the images, and disagreement was resolved by a consensus. RESULTS: Appendicoliths were identified in 134/324 patients, of which 75 had complicated appendicitis. Among 190 patients without appendicoliths, 52 had complicated appendicitis. An appendicolith was independently associated with complicated appendicitis (adjusted odds ratio 2.289; 95% CI: 1.343-3.902; p = 0.002). The larger minimum diameter was significantly associated with complication. The 4.5-/6.0-mm cutoffs for minimum and maximum diameters of appendicoliths demonstrated 82.7%/85.3% sensitivity and 35.6%/33.9% specificity in predicting complications. The PVP alone had 82.1-88.1% sensitivity, respectively per patient and per appendicolith, and a 100% specificity in the detection of appendicoliths, as compared with combined noncontrast and PVP. PVP overlooked 28/237 appendicoliths (11.8%) corresponding to 24/134 patients (17.9%). Of the 24 patients with overlooked appendicoliths, 16 had complicated appendicitis but 14 were correctly categorized by findings other than appendicoliths. In total, 2/127 patients (1.6%) with complicated appendicitis were misdiagnosed as having uncomplicated appendicitis. CONCLUSIONS: Appendicoliths in acute appendicitis were strongly associated with complications. While PVP overlooked some appendicoliths, only 1.6% of complicated appendicitis were misclassified when considering other CT findings. CLINICAL RELEVANCE STATEMENT: This study found a strong association between appendicoliths and complications. Its presence may preclude conservative management. Although portovenous-phase CT overlooked some appendicoliths, the combination with other CT findings allowed correct classification in a vast majority of cases. KEY POINTS: • Accurate identification of appendicoliths is crucial for nonoperative management decisions in adult acute appendicitis. • Appendicoliths are strongly associated with complications in adult acute appendicitis. • Portovenous-phase CT overlooked some appendicoliths, but only a small percentage of patients with complicated appendicitis were misclassified when considering other CT findings.

Value of contrast-enhanced arterial phase imaging in addition to portovenous phase in CT evaluation of blunt abdominopelvic trauma.

OBJECTIVES: Compare the diagnostic performance of the arterial phase plus portovenous phases (AP + PVP) of abdominopelvic CT (CT) with PVP alone in the detection and characterization of traumatic vascular injury and the effects on radiologists' confidence. METHODS: CT of 103 consecutive inpatients (median 36 years, 83 males) with blunt abdominopelvic injuries were retrospectively included if performed within 24 h after trauma and before definitive management. Images were re-reviewed by two blinded radiologists with disagreements resolved by the third radiologist. RESULTS: Sixty vascular injuries (liver 23, spleen 15, kidneys 9, pancreas 2, adrenals 3, mesentery, and pelvis 4 each) were found with 4 injuries (liver 2, spleen, and kidneys 1 each) not detected at initial CT. Nineteen (liver 6, spleen 10, kidneys 2, adrenal 1) were visualized only on AP. The sensitivity and accuracy of AP + PVP were 89.58-91.67% and 94.44-95.15%, compared to 61.67-62.50% and 77.67-80.00% of PVP alone. The agreements on the types of injury with final diagnoses were higher for AP + PVP than for PVP alone (78.69% vs. 44.26%). The mean diagnostic radiologist confidence ((1 = 25%, 2 = 50%, 3 = 75%, 4 > 90%) increased significantly in the detection (from 3.38 to 3.71) and characterization (from 2.46 to 3.67) of vascular injuries with AP + PVP compared to PVP alone. For 19 lesions detected only on AP, 11 (spleen 8, liver 2, adrenal 1) received nonoperative management; others had transarterial embolization or surgery. CONCLUSIONS: The addition of AP improves the detection and characterization of vascular injuries in CT evaluation of blunt abdominopelvic trauma. KEY POINTS: • AP+PVP was more sensitive and precise than PVP alone in the detection of traumatic vascular abdominopelvic injuries. • AP+PVP improved the characterization of traumatic abdominopelvic vascular injuries. • When all abdominopelvic vascular injuries were considered, AP increased radiologists' diagnostic confidence in the detection and characterization of vascular injuries.

Clear Sinus Sign on Head CT Scan: Reliable Criterion to Exclude Paranasal Sinus Fracture.

PURPOSE: The clear sinus sign has been described in facial computed tomography (CT) as an indication of the absence of fluid in the paranasal sinuses. It is a highly reliable criterion to exclude fracture involving the paranasal sinus wall. Very scarce data on this sign on head CT scan is currently available. We conducted the present study to assess the usefulness of the clear sinus sign on head CT scan to exclude paranasal sinus fracture. MATERIALS AND METHODS: A retrospective cross-sectional review of the medical records and head and facial CT images was performed for 80 trauma patients with a total of 640 paranasal sinuses. The presence and absence of paranasal sinus fracture was recorded and analyzed. RESULTS: The clear sinus sign was found in 207 paranasal sinuses (32.3%) on head CT, and none of these had a paranasal sinus fracture (P < .001). CONCLUSIONS: The presence of the clear sinus sign on head CT scans is an excellent indication for exclusion of a paranasal sinus fracture in trauma patients.

Is Combined Ultrasound with Radiography Sufficient for the Diagnosis of Obstructive Ureteric Stone in Patients with Acute Flank Pain?

CONTEXT: Ultrasound (US) is excellent for detection of hydronephrosis but has poor sensitivity for stone detection. In contrast, radiography of the kidney-ureter-bladder has better sensitivity for detection of stone but limited sensitivity for hydronephrosis detection. A combination of these two modalities may improve both sensitivity and specificity for the diagnosis of obstructive ureteric stone. AIMS: This study aims to investigate the diagnostic accuracy of combined US with radiography for the diagnosis of obstructive ureteric stone in adult patients. SETTINGS AND DESIGN: Retrospective study with retrospective data collection performed in a 1500-bed university hospital. MATERIALS AND METHODS: A total of 90 patients were included. The electronic medical record, radiological reports, laboratory results, and patient management were extracted and analyzed. STATISTICAL ANALYSIS USED: The diagnostic performance of US, radiography, and combined US with radiography were calculated and compared. The computed tomography was used as diagnostic reference. RESULTS: US alone had a sensitivity of 73.5%, specificity of 92.7%, and negative predictive value (NPV) of 74.5% for hydronephrosis. When US showed both ureteric stone and hydronephrosis, sensitivity dropped to 14.3% but specificity increased to 100%. Radiography alone had a sensitivity of 34.7%, specificity of 100%, and NPV of 56.2% for the detection of ureteric stone. Combining radiography with US raised the sensitivity for diagnosis of obstructive ureteric stone to 88% with a specificity of 93% and accuracy of 90%. CONCLUSIONS: Combined US with radiography was accurate for the diagnosis of obstructive ureteric stone in patients presenting with acute flank pain.

Key Principles in Quality and Safety in Radiology.

OBJECTIVE: The purpose of this article is to introduce the reader to basic concepts of quality and safety in radiology. CONCLUSION: Concepts are introduced that are keys to identifying, understanding, and utilizing certain quality tools with the aim of making process improvements. Challenges, opportunities, and change drivers can be mapped from the radiology quality perspective. Best practices, informatics, and benchmarks can profoundly affect the outcome of the quality improvement initiative we all aim to achieve.

Emergency Thoracic US: The Essentials.

Acute thoracic symptoms are common among adults visiting emergency departments in the United States. Adults with these symptoms constitute a large burden on the overall resources used in the emergency department. The wide range of possible causes can make a definitive diagnosis challenging, even after clinical evaluation and initial laboratory testing. In addition to radiography and computed tomography, thoracic ultrasonography (US) is an alternative imaging modality that can be readily performed in real time at the patient's bedside to help diagnose many thoracic diseases manifesting acutely and in the trauma setting. Advantages of US include availability, relatively low cost, and lack of ionizing radiation. Emergency thoracic US consists of two main parts, lung and pleura US and focused cardiac US, which are closely related. Acoustic mismatches among aerated lungs, pleura, chest wall, and pathologic conditions produce artifacts useful for diagnosis of pneumothorax and pulmonary edema and help in detection of subpleural, pleural, and chest wall pathologic conditions such as pneumonia, pleural effusion, and fractures. Visual assessment of cardiac contractility and detection of right ventricular dilatation and pericardial effusion at focused cardiac US are critical in patients presenting with acute dyspnea and trauma. Additional US examinations of the inferior vena cava for noninvasive volume assessment and of the groin areas for detection of deep venous thrombosis are often performed at the same time. This multiorgan US approach can provide valuable information for emergency treatment of both traumatic and nontraumatic thoracic diseases involving the lungs, pleura, chest wall, heart, and vascular system. Online supplemental material is available for this article. (©)RSNA, 2016.

Abdominal wall thickness is not useful to predict appendix visualization on sonography in adult patients with suspected appendicitis.

PURPOSE: To evaluate clinical and imaging factors for potential use in predicting appendix visualization on sonography (US) of adult patients with suspected appendicitis. METHODS: All adult patients who underwent appendiceal US from January through June 2010 were included in this retrospective study. Clinicopathological records were reviewed for age, sex, weight, body mass index, symptom duration, Alvarado score, surgicopathologic diagnosis, and disposition. Imaging records were collated for abdominal thicknesses, appendix visualization, and impression. The definitive diagnosis was made on pathologic evaluation. RESULTS: Eighty-six patients (68 women; median age, 35.5 years; age range, 16-86 years) met the inclusion criteria. The patients' mean weight was 56 kg; body mass index, 22.4; duration of symptoms, 24 hours; and Alvarado score, 6.5. Of the 86 patients, 37 (43%) had appendicitis. The appendix was visualized on US in 27 patients, of whom 25 had appendicitis; the appendix was not visualized in 59 patients, of whom 12 had appendicitis. There was no correlation between the clinical factors studied, the abdominal fat thickness (10.9 versus 10.7 mm; p = 0.90), or the abdominal wall thickness (16.9 versus 17.3 mm; p = 0.76) between patients with a US-visualized appendix and those whose appendix was not visualized on US. CONCLUSIONS: Abdominal thicknesses and other factors are not predictive of appendix visualization on US examination of adults with suspected appendicitis.

Characteristics of culture-negative subclinical pulmonary tuberculosis: a single-center observation.

BACKGROUND: Little is known about culture-negative subclinical pulmonary tuberculosis (TB), and its diagnosis remains challenging. Therefore, this study aimed to identify the characteristics and the extent of disease associated with culture-negative subclinical pulmonary TB. METHODS: This retrospective cohort study was conducted on immunocompetent individuals with subclinical pulmonary TB at a university hospital in Thailand from January 2014 to December 2019. Subclinical pulmonary TB was diagnosed based on the presence of radiographic abnormalities consistent with TB in the absence of TB symptoms. All subjects demonstrated significant improvement or resolution of radiographic abnormalities following the completion of treatment. At least two negative sputum cultures were needed to fulfill the definition of culture-negative pulmonary TB. Data were analyzed using univariate and multiple logistic regression analyses to determine the characteristics of those with culture-negative subclinical pulmonary TB compared to culture-positive ones. RESULTS: Out of the 106 individuals identified with subclinical pulmonary TB, 84 met the criteria for inclusion in the analysis. The study found lower radiographic extent and increasing age were key attributes of culture-negative subclinical pulmonary TB. The odds ratios (95% confidence interval) were 7.18 (1.76 to 29.35) and 1.07 (1.01 to 1.13), respectively. They tend to have lower rates of bilateral involvement in both chest x-ray (8.5% vs. 32.0%, p=0.006) and computed tomography (15.4% vs. 42.9%, p=0.035). However, no other specific radiographic findings were identified. CONCLUSIONS: People with culture-negative subclinical pulmonary TB were likely to have less radiographic -severity, reflecting early disease. Nevertheless, no radiographic patterns, except for unilaterality, were related to culture-negative subclinical pulmonary TB.

Prevalence of early bacterial co-infection in hospitalized patients with COVID-19 pneumonia: a retrospective study.

Background: Identification of bacterial co-infection is crucial in determining outcomes of patients with coronavirus disease 2019 (COVID-19) pneumonia. The present study aims to evaluate the prevalence and associated factors of early bacterial co-infection in patients with COVID-19 pneumonia. Methods: The present study is a retrospective study. Patients with COVID-19 pneumonia, who were admitted to Siriraj Hospital between April 1 and August 31, 2021, were randomly enrolled and classified as the "Early bacterial co-infection" group, defined by an infection occurring within the first 48 hours after admission, and the "Unlikely early bacterial co-infection" group. Results: A total of 245 patients were enrolled. The prevalence of early bacterial co-infection was 15.5%. Chest X-rays showed characteristic findings for COVID-19 pneumonia in 37.6%. The median Brixia chest X-ray scores and C-reactive protein levels were significantly higher in the Early bacterial co-infection group. The most common causative pathogens included Staphylococcus aureus, Pseudomonas aeruginosa, and Stenotrophomonas maltophilia. Patients with early bacterial co-infection had a significantly higher all-cause mortality compared to the Unlikely early bacterial co-infection group (P=0.012). The Charlson Comorbidity Index ≥4, high level of respiratory support, and mass-liked or diffuse opacities on chest X-rays were independent factors associated with the early bacterial co-infection. Conclusions: The prevalence of early bacterial co-infection in patients with COVID-19 pneumonia was low but it was associated with mortality. There is insufficient evidence to support the empirical use of antibiotics in these patients. A further prospective study is required to confirm the results of the present study.

Small bowel transmural necrosis secondary to acute mesenteric ischemia and strangulated obstruction: CT findings of 49 patients.

Rationale and objectives: Transmural bowel necrosis (TBN) is an uncommon surgical emergency that represents an endpoint of occlusive acute mesenteric ischemia (AMI), nonocclusive AMI and small bowel obstruction (SBO). According to limited evidence, each etiology of TBN might demonstrate a different CT finding. This investigation aimed to 1) identify overall CT findings of TBN, and 2) compare CT findings of TBN in each etiology. Materials and methods: Forty-nine consecutive adults (mean age, 64.6 years; 26 men) with occlusive AMI, nonocclusive AMI or SBO, and pathologically proven TBN were enrolled. All had a CT scan within 24 h before surgery. Clinical information was compiled from medical records. CT examinations were re-reviewed by two radiologists with disagreements resolved by the third radiologist. Data were analyzed and compared. Results: Transmural bowel necrosis were secondary to arterial AMI, venous AMI, combined arterial and venous AMI, nonocclusive AMI, and SBO in 6, 5, 2, 10, and 26 patients, respectively. The CT findings were ascites (93.9%), abnormal wall enhancement (91.8%), bowel dilatation (89.8%), mesenteric fat stranding (89.8%), abnormal wall thickness (71.5%), pneumatosis (46.9%) and intrinsic hyperattenuation of bowel walls (22.5%). Portovenous gas, mesenteric venous gas, and pneumoperitoneum were present in 4 patients (8.2%). Bowel wall thickness was the only CT findings that showed a statistically significant difference among the 5 etiologies of TBN (P = 0.046). Conclusions: Most common CT findings of TBN were ascites, abnormal bowel wall enhancement, dilatation, and mesenteric fat stranding. Wall thickness differentiated five etiologies, being most thickened in venous AMI and normal in arterial AMI.

Watch Out for the Early Killers: Imaging Diagnosis of Thoracic Trauma.

Radiologists and trauma surgeons should monitor for early killers among patients with thoracic trauma, such as tension pneumothorax, tracheobronchial injuries, flail chest, aortic injury, mediastinal hematomas, and severe pulmonary parenchymal injury. With the advent of cutting-edge technology, rapid volumetric computed tomography of the chest has become the most definitive diagnostic tool for establishing or excluding thoracic trauma. With the notion of "time is life" at emergency settings, radiologists must find ways to shorten the turnaround time of reports. One way to interpret chest findings is to use a systemic approach, as advocated in this study. Our interpretation of chest findings for thoracic trauma follows the acronym "ABC-Please" in which "A" stands for abnormal air, "B" stands for abnormal bones, "C" stands for abnormal cardiovascular system, and "P" in "Please" stands for abnormal pulmonary parenchyma and vessels. In the future, utilizing an artificial intelligence software can be an alternative, which can highlight significant findings as "warm zones" on the heatmap and can re-prioritize important examinations at the top of the reading list for radiologists to expedite the final reports.

Radiologic Imaging of Traumatic Bowel and Mesenteric Injuries: A Comprehensive Up-to-Date Review.

Diagnosing bowel and mesenteric trauma poses a significant challenge to radiologists. Although these injuries are relatively rare, immediate laparotomy may be indicated when they occur. Delayed diagnosis and treatment are associated with increased morbidity and mortality; therefore, timely and accurate management is essential. Additionally, employing strategies to differentiate between major injuries requiring surgical intervention and minor injuries considered manageable via non-operative management is important. Bowel and mesenteric injuries are among the most frequently overlooked injuries on trauma abdominal computed tomography (CT), with up to 40% of confirmed surgical bowel and mesenteric injuries not reported prior to operative treatment. This high percentage of falsely negative preoperative diagnoses may be due to several factors, including the relative rarity of these injuries, subtle and non-specific appearances on CT, and limited awareness of the injuries among radiologists. To improve the awareness and diagnosis of bowel and mesenteric injuries, this article provides an overview of the injuries most often encountered, imaging evaluation, CT appearances, and diagnostic pearls and pitfalls. Enhanced diagnostic imaging awareness will improve the preoperative diagnostic yield, which will save time, money, and lives.

Validation of scoring systems for the prediction of complicated appendicitis in adults using clinical and computed tomographic findings.

OBJECTIVES: The study aimed to evaluate scoring systems for predicting complicated appendicitis in adults diagnosed with acute appendicitis on computed tomography. METHODS: Three hundred twenty-five consecutive adult patients (mean age 51.9 ± 19.6 years, 212 women) diagnosed with acute appendicitis on computed tomography were retrospectively included. Clinical and imaging findings were compared between patients with and without complicated appendicitis, and independent associations were identified. As C-reactive protein was not available for most patients, 5 out of 8 scoring systems were modified. They, and a newly proposed system, were compared via area under the receiver operating characteristics (ROC) curve (AUC), Additionally, the latter was internally validated. Pairwise comparison was performed, and diagnostic performance of these scoring systems was obtained. RESULTS: One hundred twenty-seven patients (36.8%) had complicated appendicitis. Significant independent associations were found between complicated appendicitis and duration of symptoms > 12 h, appendicolith, periappendiceal fat stranding, periappendiceal fluid, and extraluminal air (p values < 0.001 to 0.037; AUCs of 0.824-0.829). AUCs of 9 scoring systems ranged from 0.692 to 0.831. Of these, modified Atema, Kim HY, and proposed scores had similarly high and non-significantly different AUCs (0.793-0.831) on pairwise comparison. Their sensitivities, specificities, and accuracies were 73.0-90.6%, 48.5-70.6%, and 64.3-72.3%, respectively. Internal validity test demonstrated high AUCs (0.826-0.844) with one of the proposed scores using odds ratio having 100% sensitivity and 100% negative predictive value. CONCLUSIONS: Few scoring systems, including proposed ones, had high AUCs, sensitivity, and reasonable specificities, which could potentially aid in safely selecting adult patients with acute appendicitis for nonoperative management. CRITICAL RELEVANCE STATEMENT: The study suggests few scoring systems for predicting complicated appendicitis with high AUCs and reasonable sensitivities, potentially aiding in selecting patients for nonoperative management. KEY POINTS: • The study evaluated existing and proposed new scoring systems to predict complicated appendicitis in adults with acute appendicitis on computed tomography. • Several factors were found to be significantly associated with complicated appendicitis, including duration of symptoms, appendicolith, periappendiceal fat stranding, periappendiceal fluid, and extraluminal air. • The modified Atema, Kim HY, and newly proposed scoring systems performed well, potentially aiding in nonoperative management selection.

Underdiagnosis of silicosis revealed by reinterpretation of chest radiographs in Thai ceramic workers.

Background: In Thailand, epidemiological data on silicosis in the ceramic sector is lacking and the underdiagnosis of silicosis remains an extensive concern. Therefore, this study aimed to determine the prevalence of silicosis and the extent of underdiagnosis among Thai ceramic workers by reinterpreting chest radiographs previously taken by a health check-up unit. Methods: This retrospective cross-sectional study was conducted on ceramic workers undergoing health surveillance using chest radiographs in one ceramic factory in September 2018. All chest radiographs were done retrospectively, then were reinterpreted by professional readers specially trained in using the ILO International Classification of Radiograph of Pneumoconioses (ILO/ICRP). Chest radiographs with a profusion of 1/1 or greater were suggestive of silicosis. Results: Out of the 244 participants undergoing chest radiography, the prevalence of silicosis was 2.9%. Overall, the mean age of the participants was 41 years, and 72.1% were female. Among individuals with silicosis, the median age was 43 years; 71.4% were male; the average employment duration was 26.9 years; while the male sex was the significant variable associated with silicosis with an odds ratio of 7.01 (95% confidence interval 1.31 to 37.4). Regarding the underdiagnosis, the health check-up unit failed to recognize all individuals with silicosis, and could not detect any radiographic chest abnormalities in 57.1% of those with silicosis. Conclusions: Despite the low prevalence of silicosis among Thai ceramic workers, this finding indicates ongoing exposure to silica in the ceramic industry. In addition, a significant proportion of the silicosis cases were underrecognized. Future efforts to prevent underdiagnosis and improve an occupational health surveillance service in Thailand are needed.

Performance of computed tomography and its reliability for the diagnosis of transmural gastrointestional necrosis in a setting of acute ingestion of predominantly strong acid substances in adults.

OBJECTIVES: Computed tomography has become a critical component in evaluating adult patients with acute caustic ingestions and an alternative to endoscopy for detecting transmural gastrointestinal necrosis. This study assessed the performance and reliability of computed tomography findings of transmural gastrointestinal necrosis, given that the presence of the disease potentially signifies the need for surgery. METHODS: A retrospective database search was performed to identify consecutive adult patients with acute caustic ingestions who had computed tomography with endoscopy or surgery within 72 h of admission. Eight physicians reinterpreted computed tomography in two separate rounds. Diagnostic performance utilized eight rounds of radiologists' reinterpretations against reference endoscopic or surgical grades. Intra- and interobserver agreements were calculated. RESULTS: Seventeen patients (mean age, 45.6 years; 9 men; 46 esophageal and 34 gastric segments; 16 ingested strong acid substances) met the inclusion criteria. Eight patients (10 esophageal and 13 gastric segments) had transmural gastrointestinal necrosis. The highly differentiating findings between those with and without transmural gastrointestinal necrosis were esophageal wall thickening (100% vs. 42%, P = 0.001; 100% sensitive), gastric abnormal wall enhancement and fat stranding (100% vs. 57%, P = 0.006; 100% sensitive), and gastric absent wall enhancement (46% vs. 5%, P = 0.007; 100% specific). The intra- and interobserver percentage agreements were 47-100%, and 54-100%, which increased to 53-100%, and 60-100%, respectively, when considering only radiologists' reinterpretations. CONCLUSIONS: In a very small sample of adults who primarily ingested acid, contrast-enhanced computed tomography performed well when interpreted by a panel of radiologists.

Nephrogenic systemic fibrosis.

OBJECTIVE: The purpose of this article is to discuss nephrogenic systemic fibrosis (NSF) in detail regarding its history, possible pathophysiology, clinical and pathologic presentations, diagnosis, and implications for the radiology community. CONCLUSION: NSF is a potentially lethal disorder that occurs in patients with reduced kidney function. Current evidence suggests a strong association with gadolinium-based contrast agents--mostly used in MRI--in this patient group. This has urged the radiology community to emphasize careful screening for the presence of renal dysfunction among patients for whom gadolinium-enhanced MRI is contemplated. Appropriate selection of gadolinium-based contrast agent type, avoidance of nonstandard dosage, patient education, and informed consent have been recommended by authorities.

Virtual monochromatic spectral attenuation curve analysis for evaluation of incidentally detected small renal lesions using rapid kilovoltage-switching dual-energy computed tomography.

PURPOSE: To determine whether the spectral attenuation curve on a rapid kilovoltage-switching dual-energy computed tomography (DECT) scan can distinguish enhancing from nonenhancing incidental small (1-4 cm) renal lesions compared with conventional single-energy attenuation changes. METHODS: This retrospective study enrolled 46 patients with 78 renal lesions (24 enhancing; 54 nonenhancing) who underwent DECT with DE mode performed during the portovenous or nephrographic phase. Final diagnosis of enhancing and nonenhancing masses was confirmed by pathology or imaging following the established criteria. Virtual monochromatic images (VMI) were reconstructed, and the slopes between the VMI dataset at 40-70 keV (Slope HU40-70), 40-100 keV (Slope HU40-100), and 40-140 keV (Slope HU40-140) were measured. Visual assessment of the curve pattern was recorded. Diagnostic accuracies were calculated with a cross-validated Mann-Whitney U test, and correlations of quantitative spectral parameters and intraclass correlation coefficient (ICC) were calculated using Spearman's rho correlation. RESULTS: All quantitative and qualitative spectral analysis parameters significantly differentiated the enhancing and nonenhancing lesions (P < 0.001). The optimal slope thresholds calculated by cross-validation for Slope HU40-70, Slope HU40-100, and Slope HU40-140 were 3.0, 1.8 and 1.2, respectively for reader 1 and 3.0, 1.9 and 1.15, respectively for reader 2. Using a slope threshold at all datasets yielded a high diagnostic accuracy of 96 for reader 1 and 95 for reader 2. Using a ∆HU threshold of 20 HU yielded an accuracy of 100. Visual analysis of the curve pattern also yielded high accuracy of 94. CONCLUSIONS: The spectral attenuation curve on rapid kilovoltage-switching DECT gives excellent diagnostic accuracy differentiating between incidental enhancing and nonenhancing renal lesions. This benefit of DECT will be most helpful when the true unenhanced phase is not performed.

Thoracic Inlet in Cervical Spine CT of Blunt Trauma Patients: Prevalence of Pathologies and Importance of CT Interpretation.

BACKGROUND: The thoracic inlet of blunt trauma patients may have pathologies that can be diagnosed on cervical spine computed tomography (CT) but that are not evident on concurrent portable chest radiography (pCXR). This retrospective investigation aimed to identify the prevalence of thoracic inlet pathologies on cervical spine CT and their importance by measuring the diagnostic performance of pCXR and the predictive factors of such abnormalities. METHODS: This investigation was performed at a level-1 trauma center and included CT and concurrent pCXR of 385 consecutive adult patients (280 men, mean age of 47.6 years) who presented with suspected cervical spine injury. CT and pCXR findings were independently re-reviewed, and CT was considered the reference standard. RESULTS: Traumatic, significant nontraumatic and nonsignificant pathologies were present at 23.4%, 23.6% and 58.2%, respectively. The most common traumatic diagnoses were pneumothorax (12.7%) and pulmonary contusion (10.4%). The most common significant nontraumatic findings were pulmonary nodules (8.1%), micronodules (6.8%) and septal thickening (4.2%). The prevalence of active tuberculosis was 3.4%. The sensitivity and positive predictive value of pCXR was 56.67% and 49.51% in diagnosing traumatic and 8.89% and 50% in significant nontraumatic pathologies. No demographic or pre-admission clinical factors could predict these abnormalities. CONCLUSIONS: Several significant pathologies of the thoracic inlet were visualized on trauma cervical spine CT. Since a concurrent pCXR was not sensitive and no demographic or clinical factors could predict these abnormalities, a liberal use of chest CT is suggested, particularly among those experiencing high-energy trauma with significant injuries of the thoracic inlet. If chest CT is not available, a meticulous evaluation of the thoracic inlet in the cervical spine CT of blunt trauma patients is important.

Usefulness and outcome of whole-body computed tomography (pan-scan) in trauma patients: A prospective study.

Background: Severe trauma can cause multi-organ injuries, and the mortality rate may increase if significant organ injuries are missed. This study was performed to determine whether whole-body computed tomography scan (pan-scan) can detect significant injury and leads to proper management, including alteration the priority of management. Methods: This prospective study was conducted from January 2019 to March 2021 and involved trauma patients level 1, level 2, and dangerous mechanism of trauma. Additionally, the data of trauma patients who had selective computed tomography scan were retrospectively reviewed to compared the clinical benefits. Results: Twenty-two patients were enrolled in the prospective study. The pan-scan detected significant organ injury in 86% of the patients. Prioritization of organ injury management changed after performance of the pan-scan in 64% (major change in 64.29% and minor change in 35.71%). Skull base fracture, small bowel injury, retroperitoneal injury, kidney and bladder injury, and occult pneumothorax were the majority of injuries which was not consider before underwent pan-scan (p < 0.05). The door-to-scan time tended to be shorter in the pan-scan group than in the selective scan group without a significant difference [mean (SD), 59.5 (34) and 72.0 (86) min, respectively; p = 0.13]. Pan-scan contribute 100% confidence for trauma surgeon in diagnosis of specific organ injuries in severe injured patients. Conclusions: The pan-scan facilitates timely detection of significant unexpected organ injuries such as the skull base, occult pneumothorax, small bowel, and retroperitoneum. It also helps to prioritize management and increases the diagnostic confidence of trauma surgeons, leading to better outcomes without delay.

Incidence of nephrogenic systemic fibrosis after adoption of restrictive gadolinium-based contrast agent guidelines.

PURPOSE: To retrospectively determine the incidence of nephrogenic systemic fibrosis (NSF) in a large academic medical center after the adoption of restrictive gadolinium-based contrast agent (GBCA) administration guidelines. MATERIALS AND METHODS: For this retrospective HIPAA-compliant study, institutional review board approval was obtained and the requirement for informed consent was waived. Restrictive GBCA guidelines were adopted in May 2007. The guidelines (a) require a recent serum creatinine level measurement in any patient who is aged 60 years or older and/or at risk for renal disease, (b) limit the maximal weight-based GBCA dose administered to any patient with an estimated glomerular filtration rate (eGFR) lower than 60 mL/min/m(2) to 20 mL, and (c) prohibit the administration of any GBCA in patients who have an eGFR lower than 30 mL/min/m(2) and/or are undergoing chronic dialysis treatment (except in emergency situations). The electronic medical records were searched for all contrast material-enhanced magnetic resonance (MR) imaging examinations performed during the post-guidelines adoption period between January 2008 and March 2010 and the pre-guidelines adoption and transitional period between January 2002 and December 2007. Separate pathology records were searched for biopsy-confirmed cases of NSF during the same study periods. The incidences of NSF during the pre-guidelines adoption and transitional period and post-guidelines adoption period were compared by using the paired Z test. RESULTS: A total of 52,954 contrast-enhanced MR examinations were performed during the post-guidelines adoption period. Of these 52,954 examinations, 46,464 (88%) were performed in adult patients with an eGFR of 60 mL/min/m(2) or higher or presumed normal renal function and 6454 (12%) were performed in patients with an eGFR of 30-59 mL/min/m(2). Thirty-six patients with an eGFR lower than 30 mL/min/m(2) underwent contrast-enhanced MR imaging for emergent indications. Review of the pathology records for January 2008 to September 2010 revealed no new cases of NSF resulting from GBCA exposure. CONCLUSION: After restrictive guidelines regarding GBCA administration were instituted, no new cases of NSF were identified among 52,954 contrast-enhanced MR examinations, including those performed in patients with an eGFR lower than 60 mL/min/m(2).