Nieun Seo

Clinical implications of preoperative and intraoperative liver biopsies for evaluating donor steatosis in living related liver transplantation

The role of liver biopsy in selecting optimal donors is an area of continuing controversy in living donor liver transplantation (LDLT). Our aim was to assess the potential implications of preoperative and intraoperative biopsies for evaluating donor liver fat content. Three thousand eight hundred fifty‐nine consecutive subjects underwent predonation needle biopsy of the right lobe, and 1766 of these subjects actually donated their livers for LDLT and underwent intraoperative wedge biopsies of paired right and left lobes. The preoperative workup protocol also included abdominal ultrasonography (USG) and computed tomography (CT). Intersample agreement on steatosis grades (<5%, 5% to <15%, 15% to <30%, and ≥30%) was calculated, and clinicometabolic factors related to sampling variability were evaluated. For detecting ≥30% steatosis in the 3859 potential donors, USG and CT had sensitivities of 84.9% and 57.3%, specificities of 76.3% and 92.7%, positive predictive values of 29.6% and 48.0%, and negative predictive values of 97.7% and 94.8%, respectively. Analyses of the 1766 actual donors showed that with respect to the total steatosis grades of intraoperative right and left biopsies versus preoperative biopsy, 36.7% and 36.0% of the pairs, respectively, differed from the weighted κ values of 0.44 and 0.40. Similar agreement levels existed for macrovesicular and microvesicular steatosis subtypes. The per‐subject agreement rate for the total steatosis grade between intraoperative right and left biopsies was 83.6%. According to a multivariate analysis, independent factors affecting the variability of the total steatosis results from preoperative and intraoperative biopsies (major features) were higher systolic blood pressure, body mass index, and alanine aminotransferase values and lower high‐density lipoprotein cholesterol values. In conclusion, imaging may be insufficiently sensitive for evaluating donor hepatic steatosis. Preoperative and selective intraoperative liver biopsies are mandatory for assessing donor steatosis in LDLT unless preoperative imaging demonstrates no fat. Liver Transpl 20:437–445, 2014.

Digital breast tomosynthesis versus full-field digital mammography: comparison of the accuracy of lesion measurement and characterization using specimens.

Background Digital breast tomosynthesis (DBT) is one of the new techniques being developed to overcome the inherent limitations of mammography caused by superimposed structures in a 2D projection. Purpose To compare the diagnostic performances of digital breast tomosynthesis (DBT) and full-field digital mammography (FFDM) for lesion characterization and size measurement using breast specimens. Material and Methods Out of 156 women scheduled for surgery, we included in our study 114 women, each of whom had a single, breast lesion. Three breast radiologists independently evaluated the DBT and FFDM performance regarding the breast specimens obtained during surgery. Each reader measured the lesion size, and then categorized the probability of malignancy using the American College of Radiology Breast Imaging Reporting and Data system (BI-RADS). After both reading sessions, the readers selected the preferred modality of either FFDM or DBT in lesion characterization. We also analyzed the radiologists’ evaluation performance in patients with dense versus fatty breasts when using DBT and FFDM. Results The imaging findings of 84 cancers and 30 benign lesions, all of which had been pathologically proven, were reviewed. The size evaluation determined by DBT was more accurately correlated with that found by pathology (P = 0.001 for fatty breasts and <0.001 for dense breasts) than that determined by FFDM. The correlation coefficients of DBT and FFDM to the pathologically determined lesion size were 0.90 and 0.89, respectively (P < 0.001). Compared with the pathologically determined lesion size, the size determined by both imaging modalities was overestimated. Overall, assessment of the probability of malignancy by DBT and FFDM did not differ significantly (P = 0.07); however, in dense breast, DBT was more strongly correlated with the pathology determination than FFDM (P = 0.03). Conclusion DBT may be superior to FFDM for determining the preoperative size measurement of breast lesions irregardless of their parenchymal density. Particularly in dense breasts, DBT was more useful for differentiating the lesion malignancy rate.

Intimate association of visceral obesity with non‐alcoholic fatty liver disease in healthy Asians: A case‐control study

To identify factors associated with non‐alcoholic fatty liver disease (NAFLD) in healthy Asian subjects.

Immunoglobulin G4-Related Kidney Disease: A Comprehensive Pictorial Review of the Imaging Spectrum, Mimickers, and Clinicopathological Characteristics.

Immunoglobulin G4 (IgG4)-related kidney disease (IgG4-KD) has recently been demonstrated to be an important part of IgG4-related sclerosing disease (IgG4-SD). However, since IgG4-KD is still relatively unfamiliar to radiologists and physicians as compared to IgG4-SD involving other organs, it could, therefore, be easily missed. In this article, we present a comprehensive pictorial review of IgG4-KD with regards to the imaging spectrum, mimickers, and clinicopathologic characteristics, based on our clinical experience with 48 patients during the past 13 years, as well as a literature review. Awareness of the broad imaging spectrum of IgG4-KD and differential diagnosis from its mimickers will thus facilitate its early diagnosis and treatment.

Characteristic CT features of heterotopic pancreas of the mesentery: "another pancreas" in the mesentery.

PURPOSE To evaluate computed tomography (CT) findings of heterotopic pancreas of the mesentery (HPM). METHODS Two radiologists reviewed CT scans of seven patients with HPM to determine the location, relationship with the adjacent bowel, presence of a duct-like structure, and the enhancement pattern of HPM in consensus. RESULTS All HPMs were located in the jejunal mesentery and had morphologic features closely resembling those of the main pancreas and had unique relationship with the jejunum. Duct-like structures were observed in five lesions. The enhancement pattern varied. CONCLUSION It is important to be aware of characteristic CT features of HPM to eliminate unnecessary surgeries.

Incidence and Management of Bleeding Complications Following Percutaneous Radiologic Gastrostomy

Objective Upper gastrointestinal (GI) bleeding is a serious complication that sometimes occurs after percutaneous radiologic gastrostomy (PRG). We evaluated the incidence of bleeding complications after a PRG and its management including transcatheter arterial embolization (TAE). Materials and Methods We retrospectively reviewed 574 patients who underwent PRG in our institution between 2000 and 2010. Eight patients (1.4%) had symptoms or signs of upper GI bleeding after PRG. Results The initial presentation was hematemesis (n = 3), melena (n = 2), hematochezia (n = 2) and bloody drainage through the gastrostomy tube (n = 1). The time interval between PRG placement and detection of bleeding ranged from immediately after to 3 days later (mean: 28 hours). The mean decrease in hemoglobin concentration was 3.69 g/dL (range, 0.9 to 6.8 g/dL). In three patients, bleeding was controlled by transfusion (n = 2) or compression of the gastrostomy site (n = 1). The remaining five patients underwent an angiography because bleeding could not be controlled by transfusion only. In one patient, the bleeding focus was not evident on angiography or endoscopy, and wedge resection including the tube insertion site was performed for hemostasis. The other four patients underwent prophylactic (n = 1) or therapeutic (n = 3) TAEs. In three patients, successful hemostasis was achieved by TAE, whereas the remaining one patient underwent exploration due to persistent bleeding despite TAE. Conclusion We observed an incidence of upper GI bleeding complicating the PRG of 1.4%. TAE following conservative management appears to be safe and effective for hemostasis.

CT findings of an intracardiac bronchogenic cyst

Bronchogenic cysts are classified as congenital bronchopulmonary foregut malformations. It is very rare for bronchogenic cysts to occur within the heart. A 59-year-old woman had a cardiac mass which was detected incidentally during a CT examination. The lesion was a hypoechoic mass with internal echoes on transthoracic echocardiography, and a well-defined hyperdense mass within an interatrial septum with poor enhancement on electrocardiography (ECG)-gated cardiac CT. The lesion was diagnosed as a bronchogenic cyst in the interatrial septum after surgical excision.

Comparison of CAIPIRINHA-VIBE, Radial-VIBE, and conventional VIBE sequences for dynamic contrast-enhanced (DCE) MRI: A validation study using a DCE-MRI phantom

OBJECTIVE To validate radial acquisition of volumetric interpolated breath hold examination (Radial-VIBE) and the controlled aliasing in parallel imaging results in higher acceleration (CAIPIRINHA-VIBE) sequences for dynamic contrast-enhanced MRI (DCE-MRI) by comparing them to conventional VIBE sequence using a phantom. METHODS On a DCE-MRI phantom containing various concentrations of NiCl2 solutions, six minutes of dynamic series and T1 mapping with variable flip angle methods were acquired using conventional VIBE, Radial-VIBE, and CAIPIRINHA-VIBE sequences on 3.0-T scanners. Signal stability and signal linearity were tested for dynamic series and the precision of R1 values were tested for T1 mapping series. The scans were repeatedly performed at two weeks and three months to test repeatability/reproducibility, assessed by within-subject coefficient of variation (WSCV). RESULTS Signal stability over six minutes was excellent in all three sequences. Regarding the signal linearity, CAIPIRINHA-VIBE demonstrated the highest linear correlation (r=0.963), followed by conventional VIBE (r=0.959) and Radial-VIBE (r=0.953). Regarding the R1 precision, CAIPIRINHA-VIBE (r=0.985) was the most accurate, followed by conventional VIBE (r=0.861) and Radial-VIBE (r=0.442). CAIPIRINHA-VIBE showed excellent repeatability/reproducibility (WSCV, 1.79-6.71%) compared with Radial-VIBE (WSCV, 2.04-67.2%) and conventional VIBE (WSCV, 3.4-31.9%). CONCLUSION In terms of signal stability, signal linearity, R1 precision, and repeatability/reproducibility, CAIPIRINHA-VIBE demonstrated outstanding performance for DCE-MRI compared with Radial-VIBE and conventional VIBE.

N-butyl-2 cyanoacrylate (NBCA) embolus in the graft portal vein after portosystemic collateral embolization in liver transplantation recipient: what is the clinical significance?

Background An N-butyl-2 cyanoacrylate (NBCA) embolus in the graft portal vein was frequently observed after an intraoperative embolization of portosystemic collaterals performed to prevent portal steal in liver transplant (LT) recipients. The radiological and clinical features of NBCA emboli have not yet been described. Purpose To describe radiological and clinical features of NBCA embolus in graft portal vein after portosystemic collateral embolization in LT recipients. Material and Methods A total of 165 consecutive LT recipients who had undergone intraoperative NBCA embolization of varix were found in single institution’s computerized databases of a clinical cohort of LT. Patients were evaluated for NBCA emboli (categorized into major and minor emboli according to location) on first postoperative computed tomography (CT). All electronic medical records and radiologic studies including follow-up was evaluated to determine any radiological and clinical abnormality associated with NBCA embolus. Results NBCA emboli were found in 24% (39/165) of recipients. Although most patients had minor emboli (77%, 30/39) without remarkable ultrasonography (US) abnormalities, seven (78%) of nine recipients with major emboli showed intraluminal echogenic lesions in graft portal vein on grayscale US, and five of them (71%) showed partial portal flow obstruction, although none exhibited any abnormality on contrast-enhanced US. Recipients with NBCA portal emboli showed no significant clinical abnormalities and were discharged safely. NBCA embolus eventually disappeared mostly within six months (82%, 32/39). Conclusion NBCA emboli are frequently observed after portosystemic collateral embolization in LT recipients and are not associated with poor clinical outcome. They may mimic ordinary thromboemboli on US.