Assessment of the Suitability of the Fleischner Society Imaging Guidelines in Evaluating Chest Radiographs of COVID-19 Patients.

BACKGROUND: The Fleischner Society established consensus guidelines for imaging in patients with coronavirus disease 2019 (COVID-19). We investigated the prevalence of pneumonia and the adverse outcomes by dividing groups according to the symptoms and risk factors of patients and assessed the suitability of the Fleischner society imaging guidelines in evaluating chest radiographs of COVID-19 patients. METHODS: From February 2020 to May 2020, 685 patients (204 males, mean 58 ± 17.9 years) who were diagnosed with COVID-19 and hospitalized were included. We divided patients into four groups according to the severity of symptoms and presence of risk factors (age > 65 years and presence of comorbidities). The patient groups were defined as follows: group 1 (asymptomatic patients), group 2 (patients with mild symptoms without risk factors), group 3 (patients with mild symptoms and risk factors), and group 4 (patients with moderate to severe symptoms). According to the Fleischner society, chest imaging is not indicated for groups 1-2 but is indicated for groups 3-4. We compared the prevalence and score of pneumonia on chest radiographs and compare the adverse outcomes (progress to severe pneumonia, intensive care unit admission, and death) between groups. RESULTS: Among the 685 COVID-19 patients, 138 (20.1%), 396 (57.8%), 102 (14.9%), and 49 (7.1%) patients corresponded to groups 1 to 4, respectively. Patients in groups 3-4 were significantly older and showed significantly higher prevalence rates of pneumonia (group 1-4: 37.7%, 51.3%, 71.6%, and 98%, respectively, P < 0.001) than those in groups 1-2. Adverse outcomes were also higher in groups 3-4 than in groups 1-2 (group 1-4: 8.0%, 3.5%, 6.9%, and 51%, respectively, P < 0.001). Patients with adverse outcomes in group 1 were initially asymptomatic but symptoms developed during follow-up. They were older (mean age, 80 years) and most of them had comorbidities (81.8%). Consistently asymptomatic patients had no adverse events. CONCLUSION: The prevalence of pneumonia and adverse outcomes were different according to the symptoms and risk factors in COVID-19 patients. Therefore, as the Fleischner Society recommended, evaluation and monitoring of COVID-19 pneumonia using chest radiographs is necessary for old symptomatic patients with comorbidities.

Computer-aided automatic measurement of leg length on full leg radiographs.

OBJECTIVES: To develop and evaluate a deep learning (DL)-based system for measuring leg length on full leg radiographs of diverse patients, including those with orthopedic hardware implanted for surgical treatment. METHODS: This study retrospectively assessed 2767 X-ray scanograms of 2767 patients who did or did not have orthopedic hardware implanted between January 2016 and December 2019. A cascaded DL model was developed to localize the relevant landmarks on the pelvis, knees, and ankles required for measuring leg length. Statistical analysis was performed using the correlation coefficient analysis and Bland-Altman plots to assess the agreement between the reference standard and DL-calculated lengths. RESULTS: Testing data comprised 400 radiographs from 400 patients. Of these radiographs, 100 were from patients with orthopedic hardware implanted in their pelvis, knees, or ankles. For all testing data, leg lengths derived from the DL-based measurement system, with or without internal fixation devices, showed excellent agreement with the reference standard (femoral length, r = 0.99 (P < .001); root mean square error (RMSE) = 0.17 cm; mean difference, - 0.01 ± 0.17 cm; 95% limit of agreement (LoA), - 0.35 to 0.34; tibial length, r = 0.99 (P < .001); RMSE = 0.17 cm; mean difference, - 0.02 ± 0.17 cm, 95% LoA, - 0.34 to 0.31; and full leg length, r = 1.0 (P < .001); RMSE = 0.19 cm; mean difference, 0.05 ± 0.18 cm; 95% LoA, - 0.31 to 0.40). The mean time for leg length measurement for each patient using the DL-based system was 8.68 ± 0.18 s. CONCLUSION: The DL-based leg length measurement system could provide similar performance to radiologists in terms of accuracy and reliability for a diverse group of patients.

Adverse Initial CT Findings Associated with Poor Prognosis of Coronavirus Disease.

BACKGROUND: The predictors of poor prognosis in patients with coronavirus disease 2019 (COVID-19) using computed tomography (CT) have not been investigated in a large cohort. Therefore, the purpose of this study was to investigate the adverse initial CT features to predict poor prognosis in COVID-19. METHODS: From February to April 2020, 281 COVID-19 patients who underwent CT at the time of admission were included. We divided the patients into the severe and non-severe disease groups. The severe group included patients with severe pneumonia or critical events. Intensive care unit admission or death were the critical events in this study. We compared the clinical and CT findings between the severe and non-severe groups and investigated the prognostic factors and critical events of the severe group using the regression analysis. RESULTS: Among the 281 patients, 36 (12.8%) patients were in the severe group and 245 (87.2%) patients were in the non-severe group. Critical events occurred in 10 patients (3.6%). In the severe group, patients showed significantly more pneumonia with consolidation, crazy-paving appearance, pleural effusion, and higher CT scores than those in the non-severe group (all, P < 0.05). In the multivariate regression, pleural effusion (odds ratio [OR], 8.96; 95% confidence interval [CI], 1.81-44.42; P = 0.007), CT score > 5 (OR, 3.70; 95% CI, 1.44-9.53; P = 0.007), old age (> 77 years, OR, 9.96; 95% CI, 3.78-26.28; P < 0.001), and elevated C-reactive protein (OR, 4.15; 95% CI, 1.62-10.6; P = 0.003) were significant prognostic factors of severe disease. CT score > 5 (OR, 7.29; 95% CI, 1.37-38.68; P = 0.020), pleural effusion (OR, 5.67; 95% CI, 1.04-30.8; P = 0.045) and old age (OR, 8.6; 95% CI, 1.80-41.0; P = 0.007) were also significant predictors of critical events. CONCLUSION: Pleural effusion and the extent of pneumonia on initial CT scans are associated with poor prognosis in patients with COVID-19.

Ultrasonographic Quantitative Analysis of Fatty Pancreas in Obese Children: Its Correlation with Metabolic Syndrome and Homeostasis Model Assessment of Insulin Resistance.

OBJECTIVES: To evaluate pancreatic echogenicity on transabdominal ultrasonography and the correlation of fatty pancreas with metabolic syndrome (MetS), as well as insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR]). STUDY DESIGN: This retrospective study included 135 obese children and adolescents who underwent transabdominal ultrasonography from January 2015 to December 2015. Fatty pancreas was quantitatively analyzed using the pancreato-perihepatic fat index (PPHFI). The correlation between the PPHFI and HOMA-IR was analyzed, and multivariate logistic regression analysis was used to determine factors that were independently correlated with MetS. Receiver operating characteristic curve analysis was performed to determine the best cut-off value of the PPHFI for diagnosing MetS. RESULTS: The PPHFI and the HOMA-IR value were significantly higher in subjects with MetS than in those without MetS (P < .0001). The PPHFI also showed an association with the HOMA-IR value (r = 0.70; P <.0001). The PPHFI was an independent factor for diagnosing MetS (OR 4.36; P = .032). The best cut-off value for the PPHFI for a diagnosis of MetS was 2.34 with a sensitivity of 0.96 and specificity 0.70. CONCLUSIONS: These results suggest that an increased PPHFI is significantly correlated with MetS and insulin resistance, and that the PPHFI may be a useful indicator for diagnosing MetS in obese children and adolescents. The impact of the presence of fatty pancreas in obese children and adolescents must be evaluated.

The Efficacy of Primary Interventional Urethral Realignment for the Treatment of Traumatic Urethral Injuries.

PURPOSE: To evaluate the efficacy of primary interventional urethral realignment (PIUR) in patients with traumatic urethral injuries. MATERIALS AND METHODS: This retrospective study included 13 patients with traumatic urethral injuries who were treated with PIUR between September 2008 and February 2014. All 13 patients were men with the mean age of 56.3 years. Technical success rate of PIUR, time to PIUR, required procedure time, length of hospital stay, duration of urethral catheterization, and complications after PIUR were investigated. RESULTS: PIUR was technically successful in 12 of 13 patients (92.3%). The mean time from trauma to PIUR was 44 hours (range, 1-240 h). The mean procedure time was 20.2 minutes (range, 3-90 min). The median length of hospital stay was 15 days (range, 1-60 d). The mean duration of urethral catheterization after PIUR was 25 days (range, 9-65 d). There were no immediate complications related to PIUR, although 6 of 12 patients developed symptomatic urethral stricture after PIUR. The mean time to stricture development after PIUR was 4.3 months (range, 2-12 mo). Of the 6 patients, 2 were treated with endoscopic internal urethrotomy, and 4 were treated with interventional radiologic urethral balloon dilation. CONCLUSIONS: PIUR can be safe and effective for patients with traumatic urethral injuries. However, symptomatic stricture formation occurred in one-half of the successful realignment procedures.

Sonographic Growth Charts for Kidney Length in Normal Korean Children: a Prospective Observational Study.

Kidney length is the most useful parameter for clinical measurement of kidney size, and is useful to distinguish acute kidney injury from chronic kidney disease. In this prospective observational study of 437 normal children aged between 0 and < 13 years, kidney length was measured using sonography. There were good correlations between kidney length and somatic values, including age, weight, height, and body surface area. The rapid growth of height during the first 2 years of life was intimately associated with a similar increase in kidney length, suggesting that height should be considered an important factor correlating with kidney length. Based on our findings, the following regression equation for the reference values of bilateral kidney length for Korean children was obtained: kidney length of the right kidney (cm) = 0.051 × height (cm) + 2.102; kidney length of the left kidney (cm) = 0.051 × height (cm) + 2.280. This equation may aid in the diagnosis of various kidney disorders.

Prospective randomized trial comparing pushable coil and detachable coil during percutaneous implantation of port-catheter system for hepatic artery infusion chemotherapy.

The purpose of this study was to prospectively compare the efficacy and controllability of pushable coil and detachable coil during embolization of gastroduodenal artery (GDA) while performing percutaneous implantation of port-catheter system for hepatic artery infusion chemotherapy. Fifty patients (M:F = 42:8, age: 31-81 years) with advanced hepatocellular carcinoma undergoing port-catheter system implantation were randomized into pushable coil group and detachable coil group. During catheter fixation, GDA was embolized as close to the origin as possible. Success rate, number of coils used, number of coils removed due to malposition after deployment, time to occlusion, uncoiled GDA length, pushability, and complications were compared. Pushability was graded as no tension, slight tension, and difficult to advance. Embolization was successful in 49 patients. One failure resulted from repeated regurgitation of pushable coil into hepatic artery. Number of coils used and removed coils, time to occlusion, and uncoiled GDA length were 1-3 (mean 2.32), 5 coils in 3 patients, 4-20 min (mean 8.00), and 0-15.0 mm (mean 3.36) in pushable coil group, and 1-5 (mean 2.12), 2 coils in 2 patients, 2-15 min (mean 7.40), and 0-10.2 mm (mean 2.92) in detachable coil group, respectively, without significant difference. Pushability was no tension (n = 24) and slight tension (n = 1) in pushable coil group and no tension (n = 16), slight tension (n = 7), and difficult to advance (n = 2) in detachable coil group. One hepatic artery dissection occurred in the failed case during coil removal. Pushable coils and detachable coils had similar efficacy and controllability during GDA embolization, although there was a trend favoring detachable coil.

Quantitative analysis of pancreatic echogenicity on transabdominal sonography: correlations with metabolic syndrome.

PURPOSE: To attempt a quantitative analysis of pancreatic echogenicity on transabdominal ultrasonography (US) and evaluate the correlation between pancreatic echogenicity and metabolic syndrome (MetS). METHODS: We retrospectively evaluated transabdominal sonograms from 286 subjects. Mean pancreatic body brightness, mean perihepatic fat brightness, and the pancreato-perihepatic fat index (PPHFI) were measured, and reproducibility was analyzed using intraclass correlation coefficients. Associations between the PPHFI and MetS components were analyzed. The optimal PPHFI cutoff value to predict MetS was calculated. RESULTS: Reproducibility was good for mean pancreatic body brightness, mean perihepatic fat brightness, and PPHFI with intraclass correlation coefficients of 0.98, 0.95, and 0.95, respectively. Each MetS component showed a significant association with PPHFI. Waist circumference had the strongest association (r = 0.55, p < 0.0001). PPHFI was significantly higher in the MetS (+) group than the MetS (-) group (p < 0.0001), and PPHFI was an independent factor predicting MetS (p = 0.02; odds ratio, 2.89). The best PPHFI cutoff value to predict MetS was 1.97, with a relatively high negative predictive value of 94.1%. CONCLUSIONS: We quantitatively analyzed pancreatic echogenicity using the PPHFI on US and found that an increased PPHFI was significantly correlated with MetS. Because increased PPHFI on US may indicate MetS, radiologists and clinicians need to be aware of its implications.

Apparent diffusion coefficient of uterine leiomyoma as a predictor of the potential response to uterine artery embolization.

PURPOSE: To determine the utility of the apparent diffusion coefficient (ADC) of uterine leiomyoma for prediction of the potential response to uterine artery embolization (UAE). MATERIALS AND METHODS: This prospective study included 49 patients with uterine leiomyomas who underwent diffusion-weighted magnetic resonance (MR) imaging before UAE between May 2011 and January 2012. All patients also underwent 3-month follow-up MR imaging after UAE. Using conventional and diffusion-weighted MR imaging sequences, 72 uterine leiomyomas ≥ 3 cm were prospectively evaluated. The volume of each leiomyoma was calculated, and quantitative measurement of ADC was performed. Regression analysis was used to evaluate the relationship between ADC and volumetric response after UAE. Receiver operating characteristic curve analysis was performed to determine the sensitivity and specificity of ADC for prediction of the potential response to UAE. Interclass correlation coefficient analysis was used to assess interobserver variability between two radiologists. RESULTS: Volume reduction rates of leiomyomas after UAE ranged from 0.2%-89.1% (mean, 44.1%). ADC ranged from 0.559 × 10(-3) mm(2)/s to 1.814 × 10(-3) mm(2)/s (mean, 1.170 × 10(-3) mm(2)/s). ADC was statistically significantly related to volumetric response of leiomyomas (P = .014). Using a threshold of 1.092 × 10(-3) mm(2)/s, the sensitivity and specificity of ADC for prediction of > 50% volume reduction of the leiomyoma after UAE were 82.6% and 52.3%, respectively. Using a threshold of 1.023 × 10(-3) mm(2)/s, the sensitivity and specificity of ADC for prediction of < 30% volume reduction were 80.8% and 33.3%, respectively. The interclass correlation coefficient for measuring ADC of uterine leiomyomas between two radiologists was 0.98. CONCLUSIONS: ADC of uterine leiomyomas was significantly related to the volume reduction after UAE. ADC may be useful in predicting the potential response to UAE. A high ADC of the uterine leiomyoma may be associated with a greater volume reduction after UAE.

Outcomes of endovascular management for complicated chronic type B aortic dissection: effect of the extent of stent graft coverage and anatomic properties of aortic dissection.

PURPOSE: To assess the effect of the extent of stent graft coverage and anatomic properties of aortic dissection on the outcomes of thoracic endovascular aortic repair (TEVAR) for complicated chronic type B aortic dissection (CCBAD) in terms of survival, reintervention, and false lumen thrombosis. MATERIALS AND METHODS: A retrospective analysis was performed of 71 patients who underwent TEVAR for CCBAD. Mean patient age was 54.7 years. Distal extent of stent graft coverage was categorized as short (≤ T7) or long (≥ T8) coverage. Indications of reintervention were categorized into three groups: proximal, alongside, and distal according to the anatomic relationship of the culprit lesion and the stent graft. Overall survival, reintervention-free survival, and extent of false lumen thrombosis were compared. RESULTS: The technical success rate was 97.2%. The 1-year, 3-year, and 5-year overall survival rates were 97.1%, 88.9%, and 88.9%, and 1-year, 3-year, and 5-year reintervention-free survival rates were 80.7%, 73.8%, and 60.6%. There were no differences in overall survival, reintervention-free survival rates, and extent of false lumen thrombosis between the groups. In the short coverage group, distal reintervention was more frequent in patients with an abdominal aortic diameter ≥ 37 mm compared with patients with an abdominal aortic diameter < 37 mm (P = .005). CONCLUSIONS: TEVAR was effective for CCBAD with a high technical success rate and low mortality. The extent of stent graft coverage did not make a difference in terms of survival and false lumen thrombosis. Reinterventions were more frequently performed in patients with a large baseline abdominal aortic diameter who were treated with short stent graft coverage, and so longer coverage is recommended in such patients.

Inferior Mesenteric Artery Collaterals to the Uterus during Uterine Artery Embolization: Prevalence, Risk Factors, and Clinical Outcomes.

PURPOSE: To evaluate the prevalence of inferior mesenteric artery (IMA) collaterals to the uterus found during uterine artery embolization (UAE), associated risk factors, and clinical outcomes. MATERIALS AND METHODS: The records of 559 women who underwent UAE during the period 2008-2011 for uterine fibroids or adenomyosis found on magnetic resonance imaging were retrospectively analyzed. If IMA collaterals to the uterus were suspected on aortography performed after embolization, selective angiography was performed. Risk factors for IMA collaterals to the uterus were analyzed, including the presence of adenomyosis, baseline uterine volume, or prior pelvic surgery. RESULTS: Collaterals to the uterus were found from the ovarian artery (n = 21; 3.8%), IMA (n = 7; 1.3%), round ligament artery (n = 1; 0.2%), and internal pudendal artery (n = 1; 0.2%). IMA collaterals were found in seven patients. Of 185 patients, 6 (3.2%) had adenomyosis, with or without fibroids, which was significantly more frequent than the 1 (0.27%) of 374 patients who had fibroids only (P = .006). On multiple logistic regression analysis, the presence of adenomyosis (odds ratio, 19.556; P = .0168) and uterine volume (odds ratio, 1.003; P = .0069) were independent factors for the presence of IMA collaterals. Of the seven patients with IMA collaterals, embolization was not attempted in six, resulting in clinical failure in four. One patient who underwent IMA embolization with coils experienced clinical improvement. CONCLUSIONS: The IMA was the second most common (1.3%) source of collaterals to the uterus. IMA collaterals were more frequent in patients with adenomyosis than in patients with fibroids only, resulting in high frequency of treatment failure.

A deep learning approach for fully automated measurements of lower extremity alignment in radiographic images.

During clinical evaluation of patients and planning orthopedic treatments, the periodic assessment of lower limb alignment is critical. Currently, physicians use physical tools and radiographs to directly observe limb alignment. However, this process is manual, time consuming, and prone to human error. To this end, a deep-learning (DL)-based system was developed to automatically, rapidly, and accurately detect lower limb alignment by using anteroposterior standing X-ray medical imaging data of lower limbs. For this study, leg radiographs of non-overlapping 770 patients were collected from January 2016 to August 2020. To precisely detect necessary landmarks, a DL model was implemented stepwise. A radiologist compared the final calculated measurements with the observations in terms of the concordance correlation coefficient (CCC), Pearson correlation coefficient (PCC), and intraclass correlation coefficient (ICC). Based on the results and 250 frontal lower limb radiographs obtained from 250 patients, the system measurements for 16 indicators revealed superior reliability (CCC, PCC, and ICC ≤ 0.9; mean absolute error, mean square error, and root mean square error ≥ 0.9) for clinical observations. Furthermore, the average measurement speed was approximately 12 s. In conclusion, the analysis of anteroposterior standing X-ray medical imaging data by the DL-based lower limb alignment diagnostic support system produces measurement results similar to those obtained by radiologists.

Transformers in medical image segmentation: a narrative review.

Background and Objective: Transformers, which have been widely recognized as state-of-the-art tools in natural language processing (NLP), have also come to be recognized for their value in computer vision tasks. With this increasing popularity, they have also been extensively researched in the more complex medical imaging domain. The associated developments have resulted in transformers being on par with sought-after convolution neural networks, particularly for medical image segmentation. Methods combining both types of networks have proven to be especially successful in capturing local and global contexts, thereby significantly boosting their performances in various segmentation problems. Motivated by this success, we have attempted to survey the consequential research focused on innovative transformer networks, specifically those designed to cater to medical image segmentation in an efficient manner. Methods: Databases like Google Scholar, arxiv, ResearchGate, Microsoft Academic, and Semantic Scholar have been utilized to find recent developments in this field. Specifically, research in the English language from 2021 to 2023 was considered. Key Content and Findings: In this survey, we look into the different types of architectures and attention mechanisms that uniquely improve performance and the structures that are in place to handle complex medical data. Through this survey, we summarize the popular and unconventional transformer-based research as seen through different key angles and analyze quantitatively the strategies that have proven more advanced. Conclusions: We have also attempted to discern existing gaps and challenges within current research, notably highlighting the deficiency of annotated medical data for precise deep learning model training. Furthermore, potential future directions for enhancing transformers' utility in healthcare are outlined, encompassing strategies such as transfer learning and exploiting foundation models for specialized medical image segmentation.

Ensemble deep-learning networks for automated osteoarthritis grading in knee X-ray images.

The Kellgren-Lawrence (KL) grading system is a scoring system for classifying the severity of knee osteoarthritis using X-ray images, and it is the standard X-ray-based grading system for diagnosing knee osteoarthritis. However, KL grading depends on the clinician's subjective assessment. Moreover, the accuracy varies significantly depending on the clinician's experience and can be particularly low. Therefore, in this study, we developed an ensemble network that can predict a consistent and accurate KL grade for knee osteoarthritis severity using a deep learning approach. We trained individual models on knee X-ray datasets using the most suitable image size for each model in an ensemble network rather than using datasets with a single image size. We then built the ensemble network using these models to overcome the instability of single models and further improve accuracy. We conducted various experiments using a dataset of 8260 images from the Osteoarthritis Initiative open dataset. The proposed ensemble network exhibited the best performance, achieving an accuracy of 76.93% and an F1-score of 0.7665. The Grad-CAM visualization technique was used to further evaluate the focus of the model. The results demonstrated that the proposed ensemble network outperforms existing techniques that have performed well in KL grade classification. Moreover, the proposed model focuses on the joint space around the knee to extract the imaging features required for KL grade classification, revealing its high potential for diagnosing knee osteoarthritis.

Limited efficacy of uterine artery embolization for cervical leiomyomas.

PURPOSE: To explore the effectiveness of uterine artery embolization (UAE) in treating symptomatic fibroids in the uterine cervix. MATERIALS AND METHODS: Among 537 patients who underwent UAE, 10 who had fibroids located in the cervix were retrospectively analyzed. The mean diameter of the fibroids was 6.0 cm. Seven of the 10 patients presented a total of 10 fibroids in the uterine body or fundus simultaneously. Fibroids of the cervix and fibroids in the body or fundus were compared in terms of the effects of UAE on the treatment thereof and vascularity on angiographic findings. Cervical leiomyomas were classified into three grades based on the vascularity seen on aortography, from grade I, indicating poor vascularity, to grade III, indicating hypervascularity. Necrosis of fibroids was assessed by magnetic resonance imaging 3 months after UAE. RESULTS: Complete necrosis of leiomyomas in the uterine cervix was seen in only two of the 10 patients (20%), whereas all fibroids in the uterine body or fundus were completely infarcted (P < .05). Partial necrosis (PN) of the fibroid with a thin viable rim was seen in two patients, whereas PN with a thick rim was seen in four and no necrosis was seen in two. Grade I (ie, poor) vascularity was noted in five of nine patients (55.6%) with cervical fibroids larger than 3 cm. CONCLUSIONS: Poor vascularity was a frequent finding among cervical leiomyomas, and the outcomes of UAE for cervical leiomyomas were disappointing, indicating a need for caution in selecting and counseling patients for this treatment.

Contrast-enhanced MR angiography of uterine arteries for the prediction of ovarian artery embolization in 349 patients.

PURPOSE: To assess contrast-enhanced magnetic resonance (MR) angiographic findings of uterine arteries (UAs) and to evaluate the diagnostic utility of this imaging modality for the prediction of ovarian artery (OA) embolization (OAE). MATERIALS AND METHODS: The authors retrospectively evaluated 349 patients who underwent contrast-enhanced MR angiography before UA embolization (UAE) for symptomatic fibroid tumors or adenomyosis. The diameters of the UAs were compared with those of the inferior mesenteric arteries (IMAs) and classified into two groups: group I, in which the diameters of both UAs were the same as or greater than that of the IMA; and group II, in which at least one UA was smaller than the IMA or was not visible. The presence of an enlarged OA was also evaluated. Sensitivity and specificity were calculated for UA diameter, enlarged OA, and the combination of the two. RESULTS: Nine of 22 patients (40.9%) in group II underwent OAE, which was a significantly higher incidence (P < .001) than in group I (nine of 327; 2.8%). Among eight patients with enlarged OAs, six (75%) underwent OAE. Relative UA diameter had a sensitivity of 50% and specificity of 96.1%; the respective values for enlarged OAs were 33.3% and 99.3%. The combination of UA diameter and enlarged OAs showed a sensitivity and specificity of 72.2% and 95.4%, respectively. CONCLUSIONS: In addition to the identification of enlarged OAs, contrast-enhanced MR angiography allows a comparison between UA and IMA diameters and therefore can be helpful for the prediction of OAE.

Coupling bifurcated stent-grafts to overcome anatomic limitations of endovascular repair of abdominal aortic aneurysms.

PURPOSE: To evaluate the effectiveness of the coupling stent-graft technique and outcomes on contrast-enhanced computed tomography (CT). MATERIALS AND METHODS: All patients who underwent endovascular aneurysm repair (EVAR) for abdominal aortic aneurysms (AAAs) between 2007 and 2010 at a single institution were retrospectively analyzed. Of the 161 cases, 19 patients who had coupling stent-grafting because of AAA proximal neck angulation greater than 60°, conical neck, or iliac tortuosity were included. Patient age ranged from 62 to 87 years (mean, 73.3 y). Mean follow-up was 18.7 months (range, 1-36 mo). The coupling stent-graft technique was defined by the use of suprarenal fixation device main bodies (Zenith or Talent) with one or more EXCLUDER limbs to adapt tortuous and angulated iliac arteries. Pretreatment contrast-enhanced CT was analyzed based on three-dimensional and multiplanar reformatted images. Follow-up contrast-enhanced CT was also analyzed. RESULTS: Mean aneurysm diameter was 68.9 mm ± 14.0, neck length was 32.7 mm ± 15.1, and neck angulation was 68.9° ± 11.5. Conical neck shapes were present in four patients (21.1%) and ruptured AAAs were present in two (10.5%). Among 38 iliac arteries, the mean iliac artery tortuosity index was 1.52 ± 0.27 and iliac angle was 106.8° ± 18.1. Three patients (15.8%) underwent repeat intervention: placement of a balloon-expandable stent in the proximal neck for type I endoleak (n = 1), endovascular embolization for proximal type I endoleak (n = 1), and percutaneous approach following endovascular embolization for type II endoleak (n = 1). No type III endoleak, limb occlusion, limb kinking, or stent-graft migration developed. CONCLUSIONS: The coupling stent-graft technique is technically feasible, with acceptable midterm outcomes in EVAR of AAA in patients with unfavorable neck and iliac anatomies.

Uterine artery embolization of large fibroids: comparative study of procedure with and without pretreatment gonadotropin-releasing hormone agonists.

OBJECTIVE: The purpose of this study was to evaluate the safety of pretreatment with gonadotropin-releasing hormone (GnRH) agonists before uterine artery embolization (UAE) of large fibroids. MATERIALS AND METHODS: The cases of 40 patients with large fibroids (≥ 10 cm) were retrospectively analyzed. Among the 40 patients, 28 (control group) underwent UAE without pretreatment with GnRH agonists, and 12 (GnRH group) received GnRH agonists 1-5 times before UAE. MRI was used to assess necrosis of large fibroids and their volumes in both groups within 3 months after UAE. RESULTS: Complete necrosis of large fibroids after UAE was achieved in 39 of 40 patients (97.5%). Only one patient, who was in the control group, had incomplete necrosis of the predominant fibroid. When GnRH agonists were administered before UAE, the mean volume reduction rate of fibroids was 36.3%. The final mean volume reduction rates of the predominant fibroids and the uterus after UAE in the GnRH group were 56.5% (range, 38-79%) and 50.8% (range, 35-72%), significantly higher than the volume reduction rates of 35.1% (range, 7-65%) and 34.9% (range, 16-54%) in the control group (p < 0.001). Grade D complications were not seen in the GnRH group but occurred in four patients in the control group. CONCLUSION: Pretreatment with GnRH agonists before UAE of large fibroids was safe for patients with large fibroids and did not prevent performance of UAE.

['Triangular Cord' Sign in Biliary Atresia]. / 담도폐쇄증에서 'Triangular Cord' Sign.

Biliary atresia is an unknown etiology of extrahepatic bile duct obstruction with a 'fibrous ductal remnant,' which represents the obliterated ductal remnant in the porta hepatis. The sonographic'triangular cord' (TC) sign has been reported to indicate a fibrous ductal remnant in the porta hepatis. In this review, we discuss the correlations among surgicopathological and sonographic findings of the porta hepatis and the definition, objective criteria, diagnostic accuracy, and differential diagnosis of the TC sign in biliary atresia.

Interventional urethral balloon dilatation before endoscopic visual internal urethrotomy for post-traumatic bulbous urethral stricture: A case report.

BACKGROUND: While several treatment options are available for pediatric urethral strictures, the appropriate treatment must be based on several factors. Although endoscopic visual internal urethrotomy (EVIU) could be a first-line treatment option for short pediatric urethral strictures, it is not feasible if the urethroscope cannot pass through the stricture point. Herein, we present a pediatric case of severe post-traumatic bulbous urethral stricture that was successfully treated by EVIU after securing the urethral route via interventional balloon dilatation. CASE SUMMARY: A 12-year-old boy presented at our outpatient clinic with the inability to urinate. He had sustained a straddle injury three months prior. The post-void residual urine volume was 644 mL, and retrograde urethrography confirmed severe stricture of the bulbous urethra. EVIU was planned; however, the first attempt to treat the stricture failed because the urethroscope could not pass through the stricture point. The urethral route was subsequently secured via balloon dilatation of the stricture, which was performed in collaboration with specialists from the department of interventional radiology. The urethroscope was then able to pass, and the repeat EVIU was successful. CONCLUSION: Interventional urethral balloon dilatation before EVIU may help secure the urethral route in the treatment of pediatric urethral strictures.