The prevalence of Baker cyst in relation to the arrangement pattern between the medial head of gastrocnemius tendon and the semimembranosus tendon.

PURPOSE: The purpose of this study was to investigate whether Baker cyst (BC) was related to the specific arrangement of the medial head of gastrocnemius tendon (MHGT) and the semimembranosus tendon (SMT). MATERIALS AND METHODS: Patients who underwent knee MRI with "Baker cyst" in PACS from August 2017 to February 2018 were included in this study. Patients who did not have BC in a knee MRI performed during the same period were included in the control group. A total 210 patients were selected for inclusion in this study. For the imaging analysis, the arrangement pattern between MHGT and SMT was classified into three types: type 1, concave; type 2, flat; and type 3, convex. When imaging analysis was performed, the amount of effusion, the presence of osteoarthritis, and major ligament and meniscal tears were also described. Univariate and multivariate logistic regression analyses were performed. Statistical significance was considered at p < 0.05. RESULTS: The frequency of types 1, 2, and 3 was statistically significant depending on the presence or absence of BC (p < 0.001). The frequency of type 3 was the highest in the presence of BC, while that of type 1 was the highest in the absence of BC. BC was more common in type 2 (OR = 2.54; 95% CI = 1.27-5.07) and type 3 (OR = 4.09; 95% CI = 1.88-8.89). CONCLUSION: BC is more likely to occur in patients with SMT having a convex shape for MHGT. KEY POINTS: • Based on axial image of MRI only, one can predict which patients are morphologically more prone to develop a Baker cyst. • On axial images of MRI, Baker cyst is more likely to occur in patients with semimembranosus tendon having a convex shape for medial head of gastrocnemius tendon. • Baker cyst is not associated with the amount of effusion, OA, or internal derangement.

Related Factors for Unfavorable Disease Course in Patients with Crohn's Disease: An Observational Retrospective Study.

Background: Crohn's disease (CD) manifests a heterogeneous clinical spectrum and disease course, and it is challenging to predict the disease outcome based on initial presentation. Objective: To analyze the long-term disease course and factors leading to poor prognosis of CD. Methods: In total, 112 patients with CD who were initially diagnosed and treated at our institution from January 2009 to August 2020 were included. We analyzed their clinical data, disease characteristics according to the Montreal classification, and the endoscopic and computed tomography (CT) examinations at the initial visit and at 2-year, 5-year, and last follow ups. We categorized the disease course into the following four categories: remission, stable, chronic refractory, and chronic relapsing. Significant factors associated with a poorer prognosis were analyzed. Results: The median follow-up period was 107 (range, 61−139) months. Complicated disease behavior increased slightly over the follow-up period (20.5% to 26.2%). An unfavorable disease course was defined as chronic refractory (19.6%) and relapsing (16.1%) courses. The 2-year disease characteristics were significant factors for unfavorable disease course, and the combination of 2-year perianal disease and 2-year moderate-to-severe CT activity could predict unfavorable disease course with the highest accuracy (0.722; area under the curve: 0.768; p < 0.0001). Conclusions: One-third of the patients with CD showed an unfavorable disease course (35.7%), and 2-year disease characteristics were significant factors for an unfavorable disease course.

Ultrasonography of the distal common bile duct: An easy-to-perform technique for better visualization.

BACKGROUND AND STUDY AIMS: No standard ultrasonography (US) method exists for visualizing the distal common bile duct (CBD). The supine HD view is usually adopted for CBD evaluation, but duodenal or colonic gas shadowing can affect this view. PATIENTS AND METHODS: We developed and evaluated an easy-to-perform technique, the supine distal CBD view, applying the US protocol for the distal CBD evaluation. Five reviewers checked the visibility of the distal CBD and cystic duct, as well as each view's image quality and influencing factors. RESULTS: The visibility of the distal CBD was enhanced on the supine distal CBD view (86.0%-94.6%) versus the supine hepatoduodenal view (40.8%-82.1%), with less variability among the reviewers. The image quality of the supine distal CBD view was superior to that of the supine HD view (2.52 ± 0.67 vs. 1.93 ± 0.86, respectively; p < 0.01). The depth of the distal CBD from the surface was significantly larger in the patients with nonvisible distal CBDs. CONCLUSION: We present a user-friendly, easy-to-perform US view for locating and visualizing the distal CBD. With this technique, the distal CBD can be evaluated without changing a patient's position or increasing the duration of the procedure.

[Basic Arterial Anatomy and Interpretation of CT Angiography for Intra-Abdominal or Gastrointestinal Bleeding: Correlation with Conventional Angiographic Findings for Beginners]. / 복강 내 혹은 소화기계 출혈을 이해하기 위한 ê¸°ë³¸ì ì¸ 혈관해부학과 í˜ˆê´€ì¡°ì˜ìˆ ì˜ 해석: ìž ë¬¸ìžë¥¼ 위하여.

It is essential to identify the causative artery in case of active intra-abdominal or gastrointestinal bleeding. A thorough understanding of the basic arterial anatomy is required to identify the causative artery on contrast-enhanced CT angiography and conventional catheter angiography. If one is familiar with the basic arterial anatomy, obtaining access to the bleeding artery will be easier, despite the variations in the origin and course of the vessels. We describe the basic arterial anatomy that will help beginners in diagnostic radiology to identify the blood vessels that can cause active intra-abdominal or gastrointestinal bleeding.

Shear-wave elastography in thyroid ultrasound: Can be a predictor of extrathyroidal extension and cervical lymph node metastasis in papillary thyroid carcinoma?

ABSTRACT: This study aimed to investigate whether extrathyroidal extension (ETE) and cervical lymph node metastasis (LNM) can be predicted using elasticity parameters of shear-wave elastography (SWE) combined with B-mode ultrasound (US) of papillary thyroid carcinomas (PTCs).We retrospectively reviewed 111 patients who underwent preoperative SWE evaluation among PTC patients from July 1, 2016 to June 20, 2018. Patients were divided into 2 groups based on the presence or absence of ETE based on pathology reports. Univariate and multivariate analyses of clinical and radiologic features including B-mode US features, US patterns, and SWE parameters were performed. These analyses were repeated in LNM positive and negative groups. The diagnostic performance of SWE parameters were also evaluated.Of the 111 patients, 33 had ETE, 78 did not have ETE, 44 had LNM, and 67 did not have LNM. A taller-than-wide shape and T3 stage on US were associated with ETE. Female sex, total thyroidectomy, and T3 stage on US were associated with LNM. When B-mode US and SWE were combined, there was no improvement in diagnostic performance.Combination of SWE and B-mode US findings is not useful for predicting ETE and LNM status in PTC patients.

Tumor conspicuity significantly correlates with postoperative recurrence in patients with pancreatic cancer: a retrospective observational study.

BACKGROUND: There has been scanty data regarding the clinical significance of tumor conspicuity in pancreatic cancer. In this study, we attempted to investigate the prognostic significance of pancreatic tumor conspicuity and determine prognostic factors for postoperative recurrence in patients with surgically resected pancreatic cancer. METHODS: Between January 2011 and September 2019, 62 patients who underwent preoperative computed tomography (CT) for pancreatic cancer were retrospectively included. Two reviewers evaluated various clinical, imaging, and pathologic variables and reviewed all available medical records to determine patient outcomes after surgery. Tumor conspicuity was defined as the attenuation ratio between normal parenchyma and tumor lesions on dynamic-enhanced CT images and represented the conspicuity score. Recurrence-free survival and overall survival were investigated using Cox regression analysis. RESULTS: Patient mean age was 65.9 (±11.6) years, and 56.5% were male. The median follow-up period was 11 months (range 2-138). Forty patients (64.5%) experienced postoperative recurrence, and the median time to recurrence was 6 months (range 1-101). Tumor conspicuity scores were positively correlated with both radiologic and pathologic tumor sizes (r = 0.252, 0.321, p < 0.01). Conspicuity score ≥ 2 (HR 3.8, 95% CI 1.73-8.47), elevated preoperative (HR 1.15, 95% CI; 1.02-1.28) and postoperative CA19-9 (HR 1.11, 95% CI 1.01-1.23), pathologic tumor size (HR 1.61, 95% CI 1.06-2.45), and lymphatic invasion (HR 2.76, 95% CI 1.22-6.21) were significant factors for recurrence-free survival in the multivariate analysis. CONCLUSIONS: Over half of the patients with pancreatic cancer experienced postoperative recurrence (64.5%). Increased tumor conspicuity correlated with larger tumor size and postoperative recurrence.

Shear wave elastography for the diagnosis of small (≤2 cm) breast lesions: added value and factors associated with false results.

OBJECTIVE: We compared the diagnostic performance of B-mode ultrasound, shear wave elastography (SWE), and combined B-mode ultrasound and SWE in small breast lesions (≤ 2 cm), and evaluated the factors associated with false SWE results. METHODS: A total of 428 small breast lesions (≤ 2 cm) of 415 consecutive patients between August 2013 and February 2017 were included. The diagnostic performance of each set was evaluated using the area under the receiver operating characteristic curve (AUC) analysis. Histologic diagnosis was used as reference standard. Multivariate logistic regression analyses identified the factors associated with false SWE results. RESULTS: Of 428 lesions, 142 (33.2%) were malignant and 286 (66.8%) were benign. The AUC of the combined modality was higher than that of B-mode ultrasound (0.792 vs 0.572, p < 0.001) and that of SWE was higher than that of B-mode ultrasound (0.718 vs 0.572, p < 0.001). Multivariate analysis showed that the smaller lesion size and in situ cancer were associated with false negative, and patient's age, high-risk lesion, shorter distance from the skin or chest wall, and deeper breast thickness were associated with false positive (all p < 0.05). CONCLUSIONS: The addition of SWE to B-mode ultrasound could improve the diagnostic performance in ≤ 2 cm lesions. However, ultrasound lesion size, pathology, and lesion location are likely to affect the SWE value and result in false results. ADVANCES IN KNOWLEDGE: Despite the diagnostic usefulness of SWE in small breast lesions (≤ 2 cm), ultrasound lesion size, pathology, and lesion location were associated with false results.

Genome Sequence of JangDynasty, a Newly Isolated Mycobacteriophage.

JangDynasty is a bacteriophage that infects Mycobacterium smegmatis mc2155. It has a genome length of 70,883 bp, with 124 predicted open reading frames (ORFs), 42 of which have known functions. JangDynasty belongs to cluster O, and like other cluster O phages, it is a siphovirus with a prolate capsid.