When invasively assessing coronary artery disease, the primary goal should be to determine whether the disease is causing a patient's symptoms and whether it is likely to cause future cardiac events. The presence of myocardial ischemia is our best gauge of whether a lesion is responsible for symptoms and likely to result in a future cardiac event. In the catheterization laboratory, fractional flow reserve (FFR) measured with a coronary pressure wire is the reference standard for identifying ischemia-producing lesions. Its spatial resolution is unsurpassed with it not only being vessel-specific, but also lesion-specific. There is now a wealth of data supporting the accuracy of measuring FFR to identify ischemia-producing lesions. FFR-guided percutaneous coronary intervention of these lesions results in improved outcomes and saves resources. Non-hemodynamically significant lesions can be safely managed medically with a low rate of subsequent cardiac events.

Hilar cholangiocarcinoma has an extremely poor prognosis and is usually diagnosed at an advanced stage. Palliative management plays an important role in the treatment of patients with inoperable hilar cholangiocarcinoma. Surgical, percutaneous, and endoscopic biliary drainage are three modalities available to resolve obstructive jaundice. Plastic stents were widely used in the past; however, self-expanding metal stents (SEMS) have become popular recently due to their long patency and reduced risk of side branch obstruction, and SEMS are now the accepted treatment of choice for hilar cholangiocarcinoma. Bilateral drainage provides more normal and physiological biliary flow through the biliary ductal system than that of unilateral drainage. Unilateral drainage was preferred until recently because of its technical simplicity. But, with advancements in technology, bilateral drainage now achieves a high success rate and is the preferred treatment modality in many centers. However, the choice of unilateral or bilateral drainage is still controversial, and more studies are needed. This review focuses on the endoscopic method and discusses stent materials and types of procedures for patients with a hilar cholangiocarcinoma.

Background/Aims: A similar gender-associated trend in obesity is observed worldwide. Nevertheless, systematic analyses of gender-specific characteristics in the general Korean population are rare. Methods: We analyzed the prevalence of obesity in Korean adults aged ${\geq}$ 19 years based on data collected from the Korea Health and Nutrition Examination Surveys I to IV, and verified the obesity prevalence characteristics by gender. Results: The prevalence of obesity in Korean males increased during the past 12 years from 25.1% to 35.7%, and the trend for an increase in obesity was significant in all age groups (p<0.001). In contrast, no significant trend over the past 12 years was identified for females, but the prevalence of obesity in the 30- to 39-year, 40- to 49-year, and 50- to 59-year subgroups decreased significantly (p<0.05). However, the obesity prevalence in the 60- to 69-year and > 70-year female subgroups increased significantly (p<0.05). Conclusions: We observed a gradually widening gender disparity due to an increase in the prevalence of male obesity and a decrease in the obesity prevalence among young and middle-aged women.

Background/Aims: Diastolic dysfunction occurs frequently in patients with chronic kidney disease (CKD) and is associated with heart failure (HF) or mortality. We investigated whether the ratio of early diastolic mitral inflow velocity to early diastolic mitral annulus velocity (E/e' ratio), estimated using tissue Doppler imaging, has prognostic value for cardiovascular morbidity and all-cause mortality in patients with CKD. Methods: For 186 patients with CKD of stages III to V, we obtained echocardiograms with tissue Doppler imaging. A 5-year follow-up of 136 patients was performedbased on hospital records and telephone interviews. The enrolled patients (79 males and 57 females) were categorized into the following CKD subgroups: stage III (n = 25); stage IV (n = 22); and stage V (n = 89). Results: The average follow-up period was 30.45 months and the mean age of the patients was 61.13 years. The mortality rate after 5 years was 60.0%. The causes of death were: sepsis, 21.9%; HF, 16.2%; and sudden death, 15.2%. Age (p = 0.000), increased C-reactive protein level (p = 0.018), and increased E/e′ ratio (p = 0.048) were found to correlate with mortality. Age (p = 0.000), decreased ejection fraction (p = 0.003), and increased E/e' ratio (p = 0.045) correlated with cardiovascular event. Conclusions: The E/e' ratio can predict mortality and cardiovascular events in patients with CKD who have diastolic dysfunction.

Background/Aims: This study determined the prevalence and determinants of seropositivity for rheumatoid factor (RF), anti-cyclic citrullinated peptide (anti-CCP) antibody, and anti-mutated citrullinated vimentin (anti-MCV) antibody in unaffected first-degree relatives (FDRs) of rheumatoid arthritis (RA) patients. Methods: A total of 337 subjects (135 with RA and 202 FDRs) were enrolled in this case-control study. Serum RF, anti-CCP antibody, and anti-MCV antibody were assayed. Subjects in multicase families (${\geq}$ 2 affected FDRs within the same family) were identified. Multivariate logistic regression analysis was used to identify risk factors associated with RA-related autoantibodies. Results: Seropositivity for RF, anti-CCP antibody, or anti-MCV antibody was detected in 14.4%, 5.0%, or 13.4% of unaffected FDRs, respectively. Anti-CCP antibody seropositivity was more prevalent in FDRs in multicase families (17.8%) than in those not in multicase families (1.3%, p < 0.0001). Significant correlations between RA-associated autoantibodies were detected in the FDR group (between RF and anti-CCP antibody: r = 0.366, p < 0.0001; between RF and anti-MCV antibody: r = 0.343, p < 0.0001; and between anti-CCP antibody and anti-MCV antibody: r = 0.849, p < 0.0001). After adjustment for age and sex, anti-CCP antibody seropositivity in FDRs was significantly associated with being in a multicase family (odds ratio, 49.8; 95% confidence interval, 5.6 to 441.6). Conclusions: The association between anti-CCP antibody seropositivity in unaffected FDRs and being in a multicase family suggests that genetic and/or environmental factors may increase the risk for RA development in unaffected FDRs.

Background/Aims: The causes of functional anorectal outlet obstruction (outlet obstruction) include functional defecation disorder (FDD), rectocele, and rectal intussusception (RI). It is unclear whether outlet obstruction is associated with rectal hyposensitivity (RH) in patients with functional constipation (FC). The aim of this study was to determine the association between RH and outlet obstruction in patients with FC. Methods: This was a retrospective study using a prospectively collected constipation database, and the population comprised 107 patients with FC (100 females; median age, 49 years). We performed anorectal manometry, defecography, rectal barostat, and at least two tests (balloon expulsion test, electromyography, or colon transit time study). RH was defined as one or more sensory threshold pressures raised beyond the normal range on rectal barostat. We investigated the association between the presence of RH and an outlet obstruction such as large rectocele (> 2 cm in size), RI, or FDD. Results: Forty patients (37.4%) had RH. No significant difference was observed in RH between patients with small and large rectoceles (22 [44.9%] vs. 18 [31%], respectively; p = 0.140). No significant difference was observed in RH between the non-RI and RI groups (36 [36.7%] vs. 4 [30.8%], respectively; p = 0.599). Furthermore, no significant difference in RH was observed between the non-FDD and FDD groups (19 [35.8%] vs. 21 [38.9%], respectively; p = 0.745). Conclusions: RH and outlet obstruction are common entities but appear not to be significantly associated.

Background/Aims: Obesity is correlated with numerous diseases, including thyroid cancer, but the clinical significance of obesity with regard to the clinical characteristics of thyroid cancer remains unclear. Neck circumference is an index of upper-body adipose tissue distribution. Methods: In total, 401 patients with papillary thyroid carcinoma (PTC) measuring ${\leq}$ 2cm were included. Neck circumference was measured horizontally at the level just below the thyroid cartilage on preoperative neck computed tomographic images. Results: Neck circumference correlated significantly with tumor size in men (p = 0.001) but not in women (p = 0.930). Body mass index (BMI) did not significantly correlate with tumor size in either sex. Neck circumference was significantly larger in men with lateral lymph node (LN) metastasis than in those without (p = 0.004). Neck circumference and BMI did not differ significantly in women according to other factors such as tumor size, multifocality, extrathyroid extension, and LN metastasis. Tumor size and the prevalence of lateral LN metastasis in men tended to increase in the middle/large neck circumference subgroup compared with those in the low neck circumference subgroup. Multivariate logistic regression analysis revealed that neck circumference (p = 0.009) was a predictor for the presence of lateral LN metastasis in men. BMI was not a predictive factor for lateral LN involvement in either sex. Conclusions: Neck circumference, an indicator of central or visceral obesity but not BMI, may be associated with some prognostic factors in men with small PTC.

Background/Aims: The Taxus Liberte stent (Boston Scientific Co.) evolved from the Taxus Express stent, with enhanced stent deliverability and uniform drug delivery. This study was designed to compare angiographic and clinical outcomes in real-world practice between the Taxus Liberte and Taxus Express stents. Methods: Between 2006 and 2008, 240 patients receiving the Taxus Liberte stent at three centers were registered and compared to historical control patients who had received the Taxus Express stent (n = 272). After propensity score matching, 173 patients treated with the Taxus Liberte stent and the same number of patients treated with the Taxus Express stent were selected. The primary outcome was a composite of major adverse cardiac events (MACE), including cardiac death, myocardial infarction (MI), ischemia driven target vessel revascularization (TVR), and stent thrombosis (ST) at 1 year. An additional angiographic assessment was conducted at 9 to 12 months. Results: The study showed no significant difference between the Taxus Express and Taxus Liberte stents (death, 1.73% vs. 2.31%, p = 1.000; MI, 0% vs. 1.73%, p = 0.2478; TVR, 2.31% vs. 1.16%, p = 0.6848; and ST, 0% vs. 1.16%, p = 0.4986). The total MACE rate at 1 year did not differ between the groups (4.05% in Taxus Express vs. 4.05% in Taxus Liberte, p = 1.000). In addition, the binary restenosis rate did not differ (2.25% in Taxus Express vs. 1.80% in Taxus Liberte, p = 0.6848). Conclusions: In real-world experience with the two Taxus stent designs, both stents showed similarly good clinical and angiographic outcomes at 1 year. A long-term follow-up study is warranted.

Background/Aims: Although magnetic resonance imaging (MRI) is a good visual modality for the evaluation of pituitary lesions, it has limited value in the diagnosis of mixed nodules and some cystic lesions. We evaluated the usefulness of $^{18}F$-fluorodeoxyglucose positron emission tomography (FDG PET) for patients with pituitary lesions. Methods: $^{18}F$-FDG PET and MRI were performed simultaneously in 32 consecutive patients with pituitary lesions. The relationships between FDG uptake patterns in PET and MRI findings were analyzed. Results: Of 24 patients with piuitary adenomas, 19 (79.2%) showed increased uptake of $^{18}F$-FDG in the pituitary gland on PET scans. All patients with pituitary macroadenomas showed increased $^{18}F$-FDG uptake on PET scans. Meanwhile, only five (50%) of the 10 patients with pituitary microadenomas showed positive PET scans. Interestingly, of two patients with no abnormal MRI findings, one showed increased $^{18}F$-FDG uptake on PET. For positive $^{18}F$-FDG uptake, maximum standardized uptake values $(SUV_{max})$ >2.4 had 94.7% sensitivity and 100% specificity. In addition, $(SUV_{max})$ increased in proportion to the size of pituitary adenomas. Most cystic lesions did not show $^{18}F$-FDG uptake on PET scans. Consclusions: About 80% of pituitary adenomas showed positivity on PET scans, and $(SUV_{max})$ was related to the size of the adenomas. PET may be used as an ancillary tool for detection and differentiation of pituitary lesions.

Cardiac papillary f ibroelastoma (CPF) is a rare and benign primary cardiac neoplasm of unknown prevalence. The incidence of CPF in the left ventricle is lower than that in other parts of the heart. A 65-year-old female was referred to our cardiology department for evaluation of a cardiac mass of the left ventricle. Transthoracic echocardiography revealed a $1.8{\times}1.7cm$ highly mobile round mass attached by a stalk to the apical inferior wall of the left ventricle with an echolucent area. The mass was successfully removed without any postoperative complications and was identified as a CPF.

We report a very rare case of a bronchogenic cyst combined with nontuberculous mycobacterial pulmonary disease in an immunocompetent patient. A 21-year-old male was referred to our institution because of a cough, fever, and worsening of abnormalities on his chest radiograph, despite anti-tuberculosis treatment. Computed tomography of the chest showed a large multi-cystic mass over the right-upper lobe. Pathological examination of the excised lobe showed a bronchogenic cyst combined with a destructive cavitary lesion with granulomatous inflammation. Microbiological culture of sputum and lung tissue yielded Mycobacterium avium. The patient was administered anti-mycobacterial treatment that included clarithromycin.

We describe an unusual case of systemic lupus erythematosus with pulmonary manifestations presenting as hypoglycemia due to anti-insulin receptor antibodies. A 38-year-old female suffered an episode of unconsciousness and was admitted to hospital where her blood glucose was found to be 18 mg/dL. During the hypoglycemic episode, her serum insulin level was inappropriately high (2,207.1 pmol/L; normal range, 18 to 173) and C-peptide level was elevated (1.7 nmol/L; normal range, 0.37 to 1.47). Further blood tests revealed the presence of antinuclear antibodies, anti-double-stranded DNA antibodies, and anti-Ro/SSA, anti-La/SSB, anti-ribonucleoprotein, and anti-insulin receptor antibodies. A computed tomography scan of the abdomen, aimed at tumor localization, such as an insulinoma, instead revealed ground-glass opacities in both lower lungs, and no abnormal finding in the abdomen. For a definitive diagnosis of the lung lesion, video-associated thoracoscopic surgery was performed and histopathological findings showed a pattern of fibrotic non-specific interstitial pneumonia.

Urachal cysts are uncommon. Rarely, these cysts can become infected. Tuberculosis of the urachal cyst is exceedingly rare, with only one case reported previously in the English language literature. Here we report the case of a 23-year-old male who presented with an infra-umbilical mass that turned out to be tuberculosis of the urachal cyst.