Using MRI appendicitis scale and DWI for the diagnosis of acute appendicitis in pregnant women.

OBJECTIVES: To assess the performance of MRI scale for the diagnosis of acute appendicitis in pregnant women and to determine the added diagnostic value of diffusion-weighted imaging (DWI). METHODS: From January 2018 to December 2020, 80 patients were included. All MRI were performed with a 1.5-Tesla scanner with anterior array body coil. This analysis included (1) T2-weighted imaging (T2WI), (2) fat-saturated T2WI, and (3) DWI. Two radiologists blinded to the diagnosis recorded their assessment of four findings: appendiceal diameter, appendiceal wall thickness, luminal mucus, and periappendiceal inflammation. The MRI scale of acute appendicitis which ranged from 0 to 4 was determined from these factors. An additional one point was added to the MRI appendicitis scale in those patients with evidence of appendiceal restricted diffusion on DWI. The diagnostic values and predictive factors were computed. RESULTS: Multivariate analysis demonstrated that the calculated MRI appendicitis scale was a significant independent predictor of acute appendicitis with a sensitivity of 96.6%, specificity of 90.2%, and PPV of 84.8%. The odds ratio of appendicitis is increased by 22.3 times for every increase in one point on the MRI appendicitis scale. Therefore, the addition of one point for restricted diffusion in the appendix on DWI imaging can add substantial value, both positive and negative predictive value, towards making an accurate diagnosis of acute appendicitis. CONCLUSIONS: MRI appendicitis scale is an objective and significant independent predictive factor for acute appendicitis in pregnant women. Incorporation of diffusion weighted imaging to MRI can improve diagnosis of acute appendicitis. CLINICAL RELEVANCE STATEMENT: MRI appendicitis scale is an objective and significant independent predictor of acute appendicitis in pregnant women. Incorporation of DWI/ADC map to MRI examinations can improve diagnosis of acute appendicitis in pregnant women. KEY POINTS: • MRI appendicitis scale is an objective and significant independent predictive factor for acute appendicitis in pregnant women. • The odds ratio of appendicitis can be increased by 22.3 times for every increase of one unit in MRI scale. • Incorporation of diffusion-weighted imaging to MRI examinations can add value to the scale (4.2 ± 0.7 vs. 0.7 ± 1.1; p < 0.001) among pregnant women with appendicitis versus pregnant women without appendicitis.

Quantitative Dynamic Contrast-Enhanced Magnetic Resonance Parameters Could Predict International Society of Urological Pathology Risk Groups of Prostate Cancers on Radical Prostatectomy.

BACKGROUND: The International Society of Urological Pathology (ISUP) grade and positive surgical margins (PSMs) after radical prostatectomy (RP) may reflect the prognosis of prostate cancer (PCa) patients. This study aimed to investigate whether DCE-MRI parameters (i.e., Ktrans, kep, and IAUC) could predict ISUP grade and PSMs after RP. METHOD: Forty-five PCa patients underwent preoperative DCE-MRI. The clinical characteristics and DCE-MRI parameters of the 45 patients were compared between the low- and high-risk (i.e., ISUP grades III-V) groups and between patients with or without PSMs after RP. Multivariate logistic regression analysis was used to identify the significant predictors of placement in the high-risk group and PSMs. RESULTS: The DCE parameter Ktrans-max was significantly higher in the high-risk group than in the low-risk group (p = 0.028) and was also a significant predictor of placement in the high-risk group (odds ratio [OR] = 1.032, 95% confidence interval [CI] = 1.005-1.060, p = 0.021). Patients with PSMs had significantly higher prostate-specific antigen (PSA) titers, positive biopsy core percentages, Ktrans-max, kep-median, and kep-max than others (all p < 0.05). Of these, positive biopsy core percentage (OR = 1.035, 95% CI = 1.003-1.068, p = 0.032) and kep-max (OR = 1.078, 95% CI = 1.012-1.148, p = 0.020) were significant predictors of PSMs. CONCLUSION: Preoperative DCE-MRI parameters, specifically Ktrans-max and kep-max, could potentially serve as preoperative imaging biomarkers for postoperative PCa prognosis based on their predictability of PCa risk group and PSM on RP, respectively.

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.

Contrast-enhanced CT and Acute Kidney Injury: Risk Stratification by Diabetic Status and Kidney Function.

Background Diabetes mellitus may be associated with an increased likelihood of CT contrast material-induced acute kidney injury (CI-AKI), but this has not been studied in a large sample with and without kidney dysfunction. Purpose To investigate whether diabetic status and estimated glomerular filtration rate (eGFR) are associated with the likelihood of acute kidney injury (AKI) following CT contrast material administration. Materials and Methods This retrospective multicenter study included patients from two academic medical centers and three regional hospitals who underwent contrast-enhanced CT (CECT) or noncontrast CT between January 2012 and December 2019. Patients were stratified according to eGFR and diabetic status, and subgroup-specific propensity score analyses were performed. The association between contrast material exposure and CI-AKI was estimated with use of overlap propensity score-weighted generalized regression models. Results Among the 75 328 patients (mean age, 66 years ± 17 [SD]; 44 389 men; 41 277 CECT scans; 34 051 noncontrast CT scans), CI-AKI was more likely in patients with an eGFR of 30-44 mL/min/1.73 m2 (odds ratio [OR], 1.34; P < .001) or less than 30 mL/min/1.73 m2 (OR, 1.78; P < .001). Subgroup analyses revealed higher odds of CI-AKI among patients with an eGFR less than 30 mL/min/1.73 m2, with or without diabetes (OR, 2.12 and 1.62; P = .001 and .003, respectively), when they underwent CECT compared with noncontrast CT. Among patients with an eGFR of 30-44 mL/min/1.73 m2, the odds of CI-AKI were higher only in those with diabetes (OR, 1.83; P = .003). Patients with an eGFR less than 30 mL/min/1.73 m2 and diabetes had higher odds of 30-day dialysis (OR, 1.92; P = .005). Conclusion Compared with noncontrast CT, CECT was associated with higher odds of AKI in patients with an eGFR of less than 30 mL/min/1.73 m2 and in patients with diabetes with an eGFR of 30-44 mL/min/1.73 m2; higher odds of 30-day dialysis were observed only in patients with diabetes with an eGFR less than 30 mL/min/1.73 m2. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Davenport in this issue.

Comparison of outcomes of proximal versus distal and combined splenic artery embolization in the management of blunt splenic injury: a report of 202 cases from a single trauma center.

BACKGROUND: To compare the outcomes of blunt splenic injuries (BSI) managed with proximal (P) versus distal (D) versus combined (C) splenic artery embolization (SAE). METHODS: This retrospective study included patients with BSI who demonstrated vascular injuries on angiograms and were managed with SAE between 2001 and 2015. The success rate and major complications (Clavien-Dindo classification ≥ III) were compared between the P, D, and C embolizations. RESULTS: In total, 202 patients were enrolled (P, n = 64, 31.7%; D, n = 84, 41.6%; C, n = 54, 26.7%). The median injury severity score was 25. The median times from injury to SAE were 8.3, 7.0, and 6.6 h for the P, D, and C embolization, respectively. The overall haemostasis success rates were 92.6%, 93.8%, 88.1%, and 98.1% in the P, D, and C embolizations, respectively, with no significant difference (p = 0.079). Additionally, the outcomes were not significantly different between the different types of vascular injuries on angiograms or the materials used in the location of embolization. Splenic abscess occurred in six patients (P, n = 0; D, n = 5; C, n = 1), although it occurred more commonly in those who underwent D embolization with no significant difference (p = 0.092). CONCLUSIONS: The success rate and major complications of SAE were not significantly different regardless of the location of embolization. The different types of vascular injuries on angiograms and agents used in different embolization locations also did not affect the outcomes.

Intra-Arterial Urokinase for Acute Superior Mesenteric Artery Occlusion: A Retrospective 12-Year Report of 13 Cases.

This retrospective study aimed to evaluate the outcomes of 13 patients with acute superior mesenteric artery (SMA) occlusion who underwent intra-arterial urokinase thrombolysis between 2008 and 2020. On angiography, seven presented with complete SMA occlusion versus six with incomplete occlusion. The median time from abdominal pain to attempting urokinase thrombolysis was 15.0 h (interquartile range, 6.0 h). After urokinase therapy, bowel perfusion was restored with bowel preservation in six patients; however, treatment failed in the other seven patients. The degree of SMA occlusion (complete vs. incomplete, p = 0.002), degree of recanalisation (p = 0.012), and length of stay (p = 0.032) differed significantly between groups. Of the seven patients with complete SMA occlusion, six underwent bowel resection, of whom three died, and the remaining patient died of shock due to delayed surgery. Among the six patients with incomplete SMA occlusion, no bowel resection was performed. In our experience, intra-arterial urokinase thrombolysis may serve as an adjunctive treatment modality, being a potential replacement for open thrombectomy that is able to preserve the bowel and obviate surgery in cases of incomplete SMA occlusion; however, its use is unsuitable in cases of complete SMA occlusion, for which surgery is warranted.

Comparing the Clinical Efficacy of Coil Embolization in GDA Stump versus Common Hepatic Artery in Postoperative Hemorrhage after Pancreatoduodenectomy.

BACKGROUND: Hemorrhage after pancreaticoduodenectomy is an uncommon but fatal complication. In this retrospective study, the different treatment modalities and outcomes for treating post-pancreaticoduodenectomy hemorrhage are analyzed. METHODS: Our hospital imaging database was queried to identify patients who had undergone pancreaticoduodenectomy during the period of 2004-2019. The patients were retrospectively split into three groups, according to their treatment: conservative treatment without embolization (group A: A1, negative angiography; A2, positive angiography), hepatic artery sacrifice/embolization (group B: B1, complete; B2, incomplete), and gastroduodenal artery (GDA) stump embolization (group C). RESULTS: There were 24 patients who received angiography or transarterial embolization (TAE) treatment 37 times (cases). In group A, high re-bleeding rates (60%, 6/10 cases) were observed, with 50% (4/8 cases) for subgroup A1 and 100% (2/2 cases) for subgroup A2. In group B, the re-bleeding rates were lowest (21.1%, 4/19 cases) with 0% (0/16 cases) for subgroup B1 and 100% (4/4 cases) for subgroup B2. The rate of post-TAE complications (such as hepatic failure, infarct, and/or abscess) in group B was not low (35.3%, 6/16 patients), especially in patients with underlying liver disease, such as liver cirrhosis and post-hepatectomy (100% (3/3 patients), vs. 23.1% (3/13 patients); p = 0.036, p < 0.05). The highest rate of re-bleeding (62.5%, 5/8 cases) was observed for group C. There was a significant difference in the re-bleeding rates of subgroup B1 and group C (p = 0.00017). The more iterations of angiography, the higher the mortality rate (18.2% (2/11 patients), <3 times vs. 60% (3/5 patients), ≥3 times; p = 0.245). CONCLUSIONS: The complete sacrifice of the hepatic artery is an effective first-line treatment for pseudoaneurysm or for the rupture of the GDA stump after pancreaticoduodenectomy. Hepatic complications are not uncommon and are highly associated with underlying liver disease. Conservative treatment, the selective embolization of the GDA stump, and incomplete hepatic artery embolization do not provide enduring treatment effects.

Trans-arterial embolization for intractable primary postpartum hemorrhage caused by arterial aneurysms with arteriovenous fistulas in the lower vagina bilaterally: a case report.

Failure of conservative management for controlling postpartum hemorrhage (PPH) is not uncommon, particularly when PPH is caused by vascular lesions. Awareness of this possibility and initiating timely trans-arterial embolization (TAE) are essential for improving the outcome. Herein, we describe the case of a 34-year-old woman presenting with arterial aneurysms with arteriovenous fistulas in the lower vagina bilaterally, which caused intractable PPH. Conservative management failed to resolve the PPH; however, TAE successfully controlled the bleeding, and the patient recovered smoothly. Knowledge of this possible etiology for intractable PPH is crucial for timely TAE. This case report aims to highlight the pivotal role of TAE in detecting and treating this unusual cause of PPH.

Splenic artery embolization changes the management of blunt splenic injury: an observational analysis of 680 patients graded by the revised 2018 AAST-OIS.

BACKGROUND: This study aimed to evaluate the management of blunt splenic injury (BSI) and highlight the role of splenic artery embolization (SAE). METHODS: We conducted a retrospective review of all patients with BSI over 15 years. Splenic injuries were graded by the 2018 revision of the American Association for the Surgery of Trauma-Organ Injury Scale (AAST-OIS). Our hospital provide 24/7 in-house surgeries and 24/7 in-house interventional radiology facility. Patients with BSI who arrived hypotensive and were refractory to resuscitation required surgery and patients with vascular injury on abdominal computed tomography were considered for SAE. RESULTS: In total, 680 patients with BSI, the number of patients who underwent nonoperative management with observation (NOM-obs), SAE, and surgery was 294, 234, and 152, respectively. The number of SAEs increased from 4 (8.3%) in 2001 to 23 (60.5%) in 2015 (p < 0.0001); conversely, the number of surgeries decreased from 21 (43.8%) in 2001 to 4 (10.5%) in 2015 (p = 0.001). The spleen-related mortality rate of NOM-obs, SAEs, and surgery was 0%, 0.4%, and 7.2%, respectively. In the SAE subgroup, according to the 2018 AAST-OIS, 234 patients were classified as grade II, n = 3; III, n = 21; IV, n = 111; and V, n = 99, respectively.; and compared with 1994 AST-OIS, 150 patients received a higher grade and the total number of grade IV and V injuries ranged from 96 (41.0%) to 210 (89.7%) (p < 0.0001). On angiography, 202 patients who demonstrated vascular injury and 187 achieved hemostasis after SAE with a 92.6% success rate. Six of the 15 patients failed to SAE preserved the spleen after second embolization with a 95.5% salvage rate. CONCLUSIONS: Our data confirm the superiority of the 2018 AAST-OIS and support the role of SAE in changing the trend of management of BSI.

When a Rapid Accurate Diagnosis Changes Therapeutic Approach: Recognizing Acute Abdominal Pain with Ascites as a Possible Presentation of Systemic Lupus Erythematosus.

Systemic lupus erythematosus (SLE) is a chronic, multi-organ autoimmune disease which rarely presents with peritoneal involvement. As such, its diagnosis in the emergency department (ED) based on a clinical presentation of gastrointestinal symptoms is extremely challenging. Yet, reaching such a diagnosis in the ED is crucial for avoiding unnecessary surgical intervention and initiating early glucocorticoid therapy to maximise patient outcomes. Here, we report a case of newly diagnosed SLE in a 28-year-old lady who presented atypically and unusually with abdominal pain and ascites. She required extensive but methodical investigations, and was eventually diagnosed with lupus mesenteric vasculitis with underlying newly diagnosed SLE in the ED. The patient was promptly treated with methylprednisolone resulting in marked clinical improvement. Emergency physicians should be mindful of abdominal pain with ascites as an extremely rare but important clinical presentation of SLE. Early diagnosis and commencement of glucocorticoid therapy in these patients are crucial in halting disease progression and averting the need for surgical intervention.

Effects of High-Resolution CT Changes on Prognosis Predictability in Acute Respiratory Distress Syndrome with Diffuse Alveolar Damage.

Diffuse alveolar damage (DAD) is the pathological hallmark of acute respiratory distress syndrome (ARDS). DAD is independently correlated with higher mortality compared with the absence of DAD. Traction bronchiectasis in areas of ground-glass opacity or consolidation is associated with the late fibroproliferative or fibrotic phase of DAD. This study examined whether the 60-day mortality related to DAD could be predicted using high-resolution computed tomography (HRCT) findings and HRCT scores. A total of 34 patients with DAD who received HRCT within 7 days of ARDS diagnosis were enrolled; they were divided into a 60-day survival group and a nonsurvival group, with 17 patients in each group. Univariate and multivariate binary regression analyses and the receiver operating characteristic curve revealed that only the total percentage of the area with traction bronchiectasis or bronchiolectasis was an independent predictor of 60-day mortality (odds ratio, 1.067; 95% confidence interval (CI), 1.011-1.126) and had favorable predictive performance (area under the curve (AUC): 0.784; 95% CI, 0.621-0.946; cutoff, 21.7). Physiological variables, including age, days from ARDS to HRCT, the sequential organ failure assessment (SOFA) score, the PaO2/fraction of inspired oxygen (FiO2) ratio, dynamic driving pressure, and dynamic mechanical power, were not discriminative between 60-day survival and nonsurvival. In conclusion, the extent of fibroproliferation on HRCT in early ARDS, presented as the total percentage of area with bronchiectasis or bronchiolectasis, is an independent positive predictor with a favorable predictive ability for the 60-day mortality of DAD.

Shock Index as a Predictor for Angiographic Hemostasis in Life-Threatening Traumatic Oronasal Bleeding.

The objective of this retrospective study was to identify predictors of angiographic hemostasis among patients with life-threatening traumatic oronasal bleeding (ONB) and determine the threshold for timely referral or intervention. The diagnosis of traumatic, life-threatening ONB was made if the patient suffered from craniofacial trauma presenting at triage with unstable hemodynamics or required a definitive airway due to ONB, without other major bleeding identified. There were 4404 craniofacial trauma patients between January 2015 and December 2019, of which 72 (1.6%) fulfilled the diagnosis of traumatic life-threatening ONB. Of these patients, 39 (54.2%) received trans-arterial embolization (TAE), 11 (15.3%) were treated with other methods, and 22 (30.5%) were excluded. Motor vehicle accidents were the most common cause of life-threatening ONB (52%), and the internal maxillary artery was the most commonly identified hemorrhaging artery requiring embolization (84%). Shock index (SI) was significantly higher in the angiographic hemostasis group (p < 0.001). The AUC-ROC was 0.87 (95% CI, 0.88-1.00) for SI to predict angiographic hemostasis. Early recognition and timely intervention are crucial in post-traumatic, life-threatening ONB management. Patients initially presenting with SI > 0.95 were more likely to receive TAE, with the TAE group having statistically higher SI than the non-TAE group whilst receiving significantly more packed red blood cells. Hence, for patients presenting with life-threatening traumatic ONB and a SI > 0.95, TAE should be considered if preliminary attempts at hemostasis have failed.

Diagnosis of a single gallbladder with double cystic ducts and dominant accessory duct draining into the right hepatic duct: a case report.

Biliary anomalies are a high risk for biliary injury during surgery, and although a biliary anomaly is occasionally encountered, variations in cystic ducts are rare. A preoperative diagnosis is highly valuable in facilitating surgical procedures and avoiding surgical complications. Herein, the case of a 67-year-old female patient with acute cholecystitis, in which preoperative fluoroscopic cholangiography clearly demonstrated a single gallbladder with double cystic ducts, is presented. The accessory duct was found to be dominant, draining into the otherwise normal right intrahepatic bile duct, and laparoscopic cholecystectomy was performed smoothly and successfully. Fluoroscopic cholangiography is a powerful tool that may clearly depict the anomaly of a single gallbladder with double cystic ducts. Through appropriate preoperative knowledge and demonstration of this biliary anomaly in the present case, laparoscopic cholecystectomy was safely performed, and the patient was symptom-free at the 3-year follow-up assessment.

Intravenous CT Contrast Media and Acute Kidney Injury: A Multicenter Emergency Department-based Study.

Background Although the historical risk of acute kidney injury (AKI) after intravenous administration of contrast media might be overstated, the risk in patients with impaired kidney function remains a concern. Purpose To investigate whether intravenous contrast media administration during CT is associated with a higher risk of AKI and further hemodialysis compared with the risk in patients undergoing unenhanced CT. Materials and Methods This retrospective study evaluated patients who underwent contrast-enhanced or unenhanced CT in five Taiwanese emergency departments between 2009 and 2016. The outcomes were AKI within 48-72 hours after CT, AKI within 48 hours to 1 week after CT, or further hemodialysis within 1 month after CT. The associations between contrast media exposure and outcome were estimated by using an overlap propensity score weighted generalized regression model. Subgroup analyses were performed according to the estimated glomerular filtration rate (eGFR). Results The study included 68 687 patients (median age, 68 years; interquartile range, 53-74 years; 39 995 men) with (n = 31 103) or without (n = 37 584) exposure to contrast media. After propensity score weighting, contrast media exposure was associated with higher risk of AKI within 48-72 hours after CT (odds ratio [OR], 1.16; 95% CI: 1.04, 1.29; P = .007) but no significant risk at 48 hours to 1 week after CT (OR, 1.00; 95% CI: 0.93, 1.08; P = .90). Among patients with eGFR less than 30 mL/min/1.73 m2, exposure to contrast media was associated with a higher AKI risk (48-72 hours after CT: OR, 1.36; 95% CI: 1.09, 1.70; P = .007) (48 hours-1 week after CT: OR, 1.49; 95% CI: 1.27, 1.74; P < .001) and a higher risk of hemodialysis (OR, 1.36; 95% CI: 1.09, 1.70; P = .008). For patients with eGFR greater than 45 mL/min/1.73.m2, contrast media exposure was not associated with higher AKI risk (P > .05). Conclusion Contrast-enhanced CT was associated with higher risk of acute kidney injury and further hemodialysis among Taiwanese patients with an estimated glomerular filtration rate (eGFR) of less than 30 mL/min/1.73 m2 but not those with an eGFR of more than 45 mL/min/1.73 m2. © RSNA, 2021 Online supplemental material is available for this article.

IVIM Parameters on MRI Could Predict ISUP Risk Groups of Prostate Cancers on Radical Prostatectomy.

PURPOSE: To elucidate the usefulness of intravoxel incoherent motion (IVIM)/apparent diffusion coefficient (ADC) parameters in preoperative risk stratification using International Society of Urological Pathology (ISUP) grades. MATERIALS AND METHODS: Forty-five prostate cancer (PCa) patients undergoing radical prostatectomy (RP) after prostate multiparametric magnetic resonance imaging (mpMRI) were included. The ISUP grades were categorized into low-risk (I-II) and high-risk (III-V) groups, and the concordance between the preoperative and postoperative grades was analyzed. The largest region of interest (ROI) of the dominant tumor on each IVIM/ADC image was delineated to obtain its histogram values (i.e., minimum, mean, and kurtosis) of diffusivity (D), pseudodiffusivity (D*), perfusion fraction (PF), and ADC. Multivariable logistic regression analysis of the IVIM/ADC parameters without and with preoperative ISUP grades were performed to identify predictors for the postoperative high-risk group. RESULTS: Thirty-two (71.1%) of 45 patients had concordant preoperative and postoperative ISUP grades. Dmean, D*kurtosis, PFkurtosis, ADCmin, and ADCmean were significantly associated with the postoperative ISUP risk group (all p < 0.05). Dmean and D*kurtosis (model I, both p < 0.05) could predict the postoperative ISUP high-risk group with an area under the curve (AUC) of 0.842 and a 95% confidence interval (CI) of 0.726-0.958. The addition of D*kurtosis to the preoperative ISUP grade (model II) may enhance prediction performance, with an AUC of 0.907 (95% CI 0.822-0.992). CONCLUSIONS: The postoperative ISUP risk group could be predicted by Dmean and D*kurtosis from mpMRI, especially D*kurtosis. Obtaining the biexponential IVIM parameters is important for better risk stratification for PCa.

Split-bolus computed tomography urography (CTU) achieves more than half of radiation dose reduction in females and overweight patients than conventional single-bolus computed tomography urography.

OBJECTIVE: To compare radiation dose between single-bolus and split-bolus computed tomography urography (CTU). MATERIALS AND METHODS: We prospectively enrolled patients undergoing single-bolus and split-bolus CTU from 2019 June to 2020 June. The age, sex and body mass index (BMI) of each patient was recorded and categorized into BMI classes. The radiation dose indices including volumetric computed dose index, size-specific dose estimate, dose length product and effective dose of each patient were compared between 2 CTU groups with calculation of dose reduction proportions (DRPs). RESULTS: Seventy-six patients underwent single-bolus (n = 39) and split-bolus (n = 37) CTU. Single-bolus CTU had higher radiation doses than split-bolus CTU and there were statistically significant differences of all radiation dose indices between two CTU groups without and with stratification by sex and BMI classes. The DRPs of volumetric computed dose index, size-specific dose estimate, dose length product and effective dose using split-bolus CTU were 49%, 49%. 50%, and 45%, respectively. Multiple linear regression with an effect size (f2) as 2.24 showed females (p = 0.027) and higher BMI classes (p = 2.38 *10-9) were associated with higher effective doses; and split-bolus CTU, lower effective doses (p = 5.40 *10-15). Using split-bolus CTU, females had consistently higher DRP of all radiation dose indices than males (54-55% versus 40-42%). Overweight patients had the largest DRP as 55% of effective dose. CONCLUSIONS: Split-bolus CTU could be preferred by its significant radiation dose reduction effect in regard to single-bolus CTU, which was most profound in females and overweight patients.

Differences of liver CT perfusion of blunt trauma treated with therapeutic embolization and observation management.

Massive hepatic necrosis after therapeutic embolization has been reported. We employed a 320-detector CT scanner to compare liver perfusion differences between blunt liver trauma patients treated with embolization and observation. This prospective study with informed consent was approved by institution review board. From January 2013 to December 2016, we enrolled 16 major liver trauma patients (6 women, 10 men; mean age 34.9 ± 12.8 years) who fulfilled inclusion criteria. Liver CT perfusion parameters were calculated by a two-input maximum slope model. Of 16 patients, 9 received embolization and 7 received observation. Among 9 patients of embolization group, their arterial perfusion (78.1 ± 69.3 versus 163.1 ± 134.3 mL/min/100 mL, p = 0.011) and portal venous perfusion (74.4 ± 53.0 versus 160.9 ± 140.8 mL/min/100 mL, p = 0.008) were significantly lower at traumatic parenchyma than at non-traumatic parenchyma. Among 7 patients of observation group, only portal venous perfusion was significantly lower at traumatic parenchyma than non-traumatic parenchyma (132.1 ± 127.1 vs. 231.1 ± 174.4 mL/min/100 mL, p = 0.018). The perfusion index between groups did not differ. None had massive hepatic necrosis. They were not different in age, injury severity score and injury grades. Therefore, reduction of both arterial and portal venous perfusion can occur when therapeutic embolization was performed in preexisting major liver trauma, but hepatic perfusion index may not be compromised.

Prolonged international normalized ratio and vascular injury at divisional level predict embolization failures of patients with iatrogenic renal vascular injuries.

Transcatheter arterial embolization (TAE), as an alternative to surgery for iatrogenic renal vascular injury (IRVI), may have unsatisfactory outcomes. Nonetheless, there is inadequate information regarding the predictors of TAE outcomes for IRVI in the literature. The aim of this retrospective study was to investigate the predictors of TAE outcomes for IRVI. Of 47 patients, none had major complications, 17 (36.2%) patients had minor complications, and none suffered significant renal function deterioration after TAE. Technical success and clinical success were 91.5% and 93.6%, respectively. Technical failure was associated with older age, thrombocytopenia, prolonged international normalized ratio (INR) and divisional IRVI. Clinical failure was associated with kidney failure, use of steroids, prolonged INR, and divisional IRVI. In addition, prolonged INR was a significant predictor of technical failure. This implies that aggressive measures to control the INR prior to TAE are warranted to facilitate technical success, and technical success could then be validated on post-TAE images. Furthermore, divisional IRVI was a predictor of clinical failure. Thus, divisional IRVI should undergo surgery first since TAE is prone to clinical failure. The avoidance of clinical failure is validated if divisional IRVI does not need further intervention.

Identifying the optimal inlet for antegrade tibial intramedullary nailing via magnetic resonance imaging.

INTRODUCTION: Tibial shaft fractures treated with antegrade rigid tibial intramedullary nailing has been supported worldwide. However, the optimal inlet for nailing is still controversial. Practically, varied inlets may significantly affect the tibial alignment. This retrospective study intended to utilize magnetic resonance imaging (MRI) to investigate the optimal inlet for antegrade tibial nailing. METHODS: MRIs of 100 consecutive adult patients (50 men and 50 women, average 27 years) were used in this study. All patients had MRIs for meniscus or knee ligament injuries. There were no fractures or prior bony anomalies. The center of the tibial width (TW) at the level of the tibial tubercle (TT) was considered the optimal inlet and was positioned on the axial view of the MRIs. Various related anatomic landmarks were investigated concomitantly. All parameters were compared statistically. RESULTS: The medial edge of the patellar tendon (PT) was 55% from the lateral end of the TW. The apex of the TT was 38% from the lateral end of the TW. The lateral edge of the PT was 19% from the lateral end of the TW. The TT was 2.5 cm distal to the tibial articular surface. The PT width was 2.3 cm. Except for the TW, the distance from the TT to the articular surface, and PT width between genders (p < 0.001), all other parameters showed no statistical significance (p >  0.05). CONCLUSIONS: The optimal inlet for antegrade rigid tibial intramedullary nailing may be at a site 3 mm laterally to the medial edge of the PT. There are normally no differences for the nail inlet between men and women. The PT splitting approach for nail insertion may require modification.

Metanephric adenoma with low apparent diffusion coefficient value mimicking renal cell carcinoma: A case report.

RATIONALE: Metanephric adenoma (MA) is a rare and often benign tumor. Most MAs were misdiagnosed as renal cell carcinomas (RCCs) preoperatively. Diffusion weighted imaging (DWI) and apparent diffusion coefficient (ADC) mapping can help to differentiate benign and malignant tumors. However, there are still pitfalls in using DWI and ADC to discriminate benign and malignant lesions. PATIENT CONCERNS: A 56-year-old woman had a right renal metanephric adenoma. The tumor showed very low ADC value preoperatively and was misdiagnosed as a renal cell carcinoma. DIAGNOSIS: Intraoperative ultrasound-guided percutaneous biopsy of tumor was performed. Based on the histopathological findings and immunohistochemical stains, a diagnosis of metanephric adenoma was suggested. INTERVENTIONS: The patient received percutaneous cryoablation of this tumor. Five years later, she underwent right partial nephrectomy because local recurrence was revealed on a follow-up computed tomography (CT). OUTCOMES: MA was confirmed again by histological examination. The patient was uneventful after surgery. LESSONS: ADC mapping can be used for differentiating RCCs from other benign tumors by their lower ADC values. However, some benign and malignant lesions have overlapped low ADC values. This case illustrated that a benign lesion such as MA could mimic RCC on ADC, by its highly cellular component. Cryoablation is an optional treatment, which has an increased risk of local recurrence. Follow-up CT or MRI is useful and necessary for detection of local recurrence by depicting enhancing solid parts in a tumor over time.