A comparison of rapid rule-learning strategies in humans and monkeys.

Inter-species comparisons are key to deriving an understanding of the behavioral and neural correlates of human cognition from animal models. We perform a detailed comparison of the strategies of female macaque monkeys to male and female humans on a variant of the Wisconsin Card Sort Test (WCST), a widely studied and applied task that provides a multi-attribute measure of cognitive function and depends on the frontal lobe. WCST performance requires the inference of a rule change given ambiguous feedback. We found that well-trained monkeys infer new rules three times more slowly than minimally instructed humans. Input-dependent Hidden Markov Model-Generalized Linear Models were fit to their choices, revealing hidden states akin to feature-based attention in both species. Decision processes resembled a Win-Stay Lose-Shift strategy with inter-species similarities as well as key differences. Monkeys and humans both test multiple rule hypotheses over a series of rule-search trials and perform inference-like computations to exclude candidate choice options. We quantitatively show that perseveration, random exploration and poor sensitivity to negative feedback account for the slower task-switching performance in monkeys.Significance Statement Advances in training and recording from animal models support the study of increasingly complex behaviors in non-humans. Before interpreting their neural computations as human-like, we must first ascertain whether their computational algorithms are human-like. We compared rapid rule-learning strategies of macaque monkeys and humans on a Wisconsin Card Sorting Test variant and found that monkeys are 3-4 times slower than humans at learning new rules. Model fits to choice behavior revealed that both species use qualitatively similar exploration strategies with different decision criteria. These differences produced distinct errors in monkeys that are similar to those observed in humans with prefrontal deficits. Our results generate detailed neural hypotheses and highlight the need for systematic inter-species behavioral and neural comparisons.

Comparison of Four Diagnostic Guidelines for Hepatocellular Carcinoma Using Gadoxetic Acid-enhanced Liver MRI.

Background Noninvasive diagnostic guidelines for hepatocellular carcinoma (HCC) vary across different global geographic areas, especially regarding criteria about gadoxetic acid-enhanced MRI. Purpose To compare the diagnostic performance of four different international HCC diagnosis guidelines and readers' judgment in diagnosing HCC using gadoxetic acid-enhanced MRI in patients at high risk for HCC. Materials and Methods This retrospective study included patients who had not undergone treatment, were at risk for HCC, and who underwent gadoxetic acid-enhanced MRI from January 2015 to June 2018 from 11 tertiary hospitals in South Korea. Four radiologists independently reviewed focal liver lesions (FLLs) according to four guidelines: American Association for the Study of Liver Diseases (AASLD)/Liver Imaging Reporting and Data System (LI-RADS), Korean Liver Cancer Association-National Cancer Center (KLCA-NCC), European Association for the Study of the Liver (EASL), and Asian Pacific Association for the Study of the Liver (APASL). Reader judgment (HCC or not HCC) was also recorded. Malignant FLLs were confirmed at pathology, and histologic and clinical follow-up data were used for benign FLLs. The guidelines' diagnostic performance was compared using generalized estimating equations. Additionally, the diagnostic odds ratio was assessed. Results A total of 2445 FLLs (median size, 27.4 mm) were analyzed in 2237 patients (mean age, 59 years ± 11 [SD]; 1666 male patients); 69.3% (1694 of 2445) were HCCs. KLCA-NCC showed the highest accuracy (80.0%; 95% CI: 78.7, 81.2; P = .001), with high sensitivity in Eastern guidelines (APASL, 89.1% [95% CI: 87.8, 90.3]; KLCA-NCC, 78.2% [95% CI: 76.6, 79.7]) and high specificity in Western guidelines (AASLD/LI-RADS, 89.6% [95% CI: 87.8, 91.2]; EASL, 88.1% [95% CI: 86.2, 89.9]) (P = .001). The diagnostic odds ratios were 20.7 (95% CI: 17.0, 25.3) for AASLD/LI-RADS, 18.9 (95% CI: 15.8, 22.6) for KLCA-NCC, 16.8 (95% CI: 13.8, 20.4) for EASL, and 8.9 (95% CI: 7.4, 10.7) for APASL. The readers' judgment demonstrated higher accuracy than that of the guidelines (accuracy, 86.0%; 95% CI: 84.9, 86.9; P = .001). Conclusion Among four different international HCC diagnosis guidelines, Eastern guidelines demonstrated higher sensitivity, whereas Western guidelines displayed higher specificity. KLCA-NCC achieved the highest accuracy, and AASLD/LI-RADS exhibited the highest diagnostic odds ratio. © RSNA, 2024 Supplemental material is available for this article.

Current Status of Anti-Reflux Surgery as a Treatment for GERD.

Anti-reflux surgery (ARS) is an efficient treatment option for gastroesophageal reflux disease (GERD). Despite growing evidence of the efficacy and safety of ARS, medications including proton pump inhibitors (PPIs) remain the most commonly administered treatments for GERD. Meanwhile, ARS can be an effective treatment option for patients who need medications continuously or for those who are refractory to PPI treatment, if proper candidates are selected. However, in practice, ARS is often regarded as a last resort for patients who are unresponsive to PPIs. Accumulating ARS-related studies indicate that surgery is equivalent to or better than medical treatment for controlling typical and atypical GERD symptoms. Furthermore, because of overall reduced medication expenses, ARS may be more cost-effective than PPI. Patients are selected for ARS based on endoscopic findings, esophageal acid exposure time, and PPI responsiveness. Although there is limited evidence, ARS may be expanded to include patients with normal acid exposure, such as those with reflux hypersensitivity. Additionally, other factors such as age, body mass index, and comorbidities are known to affect ARS outcomes; and such factors should be considered. Nissen fundoplication or partial fundoplication including Dor fundoplication and Toupet fundoplication can be chosen, depending on whether the patient prioritizes symptom improvement or minimizing postoperative symptoms such as dysphagia. Furthermore, efforts to reduce and manage postoperative complications and create awareness of the long-term efficacy and safety of the ARS are recommended, as well as adequate training programs for new surgeons.

Abbreviated MRI with second shot arterial phase for HCC evaluation: modified version of LI-RADS and recall reduction strategy.

OBJECTIVES: To evaluate the feasibility of simulated abbreviated MRI (AMRI) with second shot arterial phase (SSAP) for HCC surveillance and diagnosis. METHODS: A total of 129 consecutive patients (age, 58.8 ± 11.4 years; male, 71.3%) underwent gadoxetic acid-enhanced MRI using a modified injection protocol for HCC evaluation from July 2017 to February 2018. The modified injection protocol consisted of routine dynamic imaging (6 mL) and SSAP imaging (4 mL). Two radiologists independently reviewed two AMRI sets: AMRI without SSAP (surveillance set) and AMRI with SSAP (diagnosis set). A modified version of the Liver Imaging Reporting and Data System (LI-RADS) for the diagnosis set was devised by referring to contrast-enhanced ultrasound LI-RADS. RESULTS: Sixty-seven patients with HCC and 62 patients without HCC were included. In the surveillance set, sensitivity and specificity for the detection of patients with HCC were 95.5% and 96.8%, and 94.0% and 96.8% in reviewers 1 and 2, respectively. In the diagnosis set, the scores of most HCCs (76/78, 97.4%) were consistent between LI-RADS of full-protocol and modified LI-RADS of AMRI with SSAP protocol. When the HCC surveillance and diagnosis strategy was changed from strategy 1 (AMRI without SSAP) to strategy 2 (AMRI with SSAP), the recall rate significantly decreased from 52.7 to 3.9% (p < 0.001). CONCLUSIONS: The modified LI-RADS score of the AMRI with SSAP protocol showed high agreement with the LI-RADS score of the full protocol. The HCC surveillance and diagnosis strategy using the AMRI with SSAP protocol reduced the recall rate. These results may enable to diagnose HCC simultaneously with surveillance. KEY POINTS: • A modified version of LI-RADS was devised for the diagnostic algorithm using AMRI with the second shot arterial phase (SSAP) by referring to CEUS LI-RADS. • The modified LI-RADS scores using AMRI with SSAP showed a high concordance rate with the conventional LI-RADS score using full-protocol MRI. • The recall rate significantly decreased when the HCC surveillance and diagnosis strategy was changed from strategy 1 (AMRI without SSAP; surveillance then recall test) to strategy 2 (AMRI with SSAP; simultaneous surveillance and diagnosis).

Apoptotic Effect of Gallic Acid via Regulation of p-p38 and ER Stress in PANC-1 and MIA PaCa-2 Cells Pancreatic Cancer Cells.

Pancreatic cancer (PC) is currently recognized as the seventh most prevalent cause of cancer-related mortality among individuals of both genders. It is projected that a significant number of individuals will succumb to this disease in the forthcoming years. Extensive research and validation have been conducted on both gemcitabine and 5-fluorouracil as viable therapeutic options for PC. Nevertheless, despite concerted attempts to enhance treatment outcomes, PC continues to pose significant challenges in terms of achieving effective treatment alone through chemotherapy. Gallic acid, an endogenous chemical present in various botanical preparations, has attracted considerable attention due to its potential as an anticancer agent. The results of the study demonstrated that gallic acid exerted a decline in cell viability that was dependent on its concentration. Furthermore, it efficiently suppressed cell proliferation in PC cells. This study observed a positive correlation between gallic acid and the production of reactive oxygen species (ROS). Additionally, it confirmed the upregulation of proteins associated with the protein kinase-like endoplasmic reticulum kinase (PERK) pathway, which is one of the pathways involved in endoplasmic reticulum (ER) stress. Moreover, the administration of gallic acid resulted in verified alterations in the transmission of mitogen-activated protein kinase (MAPK) signals. Notably, an elevation in the levels of p-p38, which represents the phosphorylated state of p38 MAPK was detected. The scavenger of reactive oxygen species (ROS), N-Acetyl-L-cysteine (NAC), has shown inhibitory effects on phosphorylated p38 (p-p38), whereas the p38 inhibitor SB203580 inhibited C/EBP homologous protein (CHOP). In both instances, the levels of PARP have been successfully reinstated. In other words, the study discovered a correlation between endoplasmic reticulum stress and the p38 signaling pathway. Consequently, gallic acid induces the activation of both the p38 pathway and the ER stress pathway through the generation of ROS, ultimately resulting in apoptosis. The outcomes of this study provide compelling evidence to support the notion that gallic acid possesses considerable promise as a viable therapeutic intervention for pancreatic cancer.

Efficacy of 2-stage revision using a prosthesis of antibiotic-loaded acrylic cement spacer with or without cortical strut allograft in infected total elbow arthroplasty.

PURPOSE: We aimed to evaluate the efficacy of a self-manufactured prosthesis of antibiotic-loaded acrylic cement (PROSTALAC) spacer with or without cortical strut allograft in infected total elbow arthroplasty. METHODS: Between March 2009 and February 2018, we enrolled 18 patients (mean age, 66.9 years) who underwent 2-stage revision arthroplasty for prosthetic infection following total elbow arthroplasty. After implant removal in the first stage, we performed débridement and PROSTALAC insertion. During the second stage, we performed reimplantation using a cortical strut allograft for patients with a considerably severe bone defect. The mean follow-up period was 34 months (range, 25-60 months), during which we evaluated the Mayo Elbow Performance Score (MEPS), range of motion (ROM), and blood markers. RESULTS: In all 18 patients, infection control was ensured using intravenous (IV) antibiotic therapy for 6 weeks or IV antibiotics for 4 weeks converting to oral antibiotics for 2 weeks following PROSTALAC insertion. The mean visual analog scale score improved from 8 points preoperatively to 2 points postoperatively, and the mean MEPS improved from 32 points preoperatively to 82 points postoperatively (P < .05). The average ROMs at the last follow-up were 9° to 132° from extension to flexion, respectively. Two patients experienced ulnar nerve neuropraxia after surgery, from which they were resolved. Moreover, 2 and 4 patients developed superficial wound infection and triceps insufficiency, respectively, and there was no infection recurrence. CONCLUSION: In the management of elbow prosthetic infection, 2-stage revision arthroplasty using PROSTALAC spacer insertion in the first stage and cortical strut allograft in the second stage for patients with severe bone defect revealed good clinical results and relatively low infection recurrence rates. However, the complication rate is substantial.

Comparative Clinical Evaluation of NeoPlex RB-8 with Seeplex PneumoBacter ACE for Simultaneous Detection of Eight Respiratory Bacterial Pathogens.

There are several convenient and accurate molecular assays to detect respiratory bacterial infection. The NeoPlex RB-8 detection kit (NeoPlex RB-8) is a new multiplex real-time PCR assay that simultaneously detects Streptococcus pneumoniae, Mycoplasma pneumoniae, Chlamydophila pneumoniae, Legionella pneumophila, Haemophilus influenzae, Bordetella pertussis, Bordetella parapertussis, and Moraxella catarrhalis in a single test. This study compared the clinical concordance of NeoPlex RB-8 with another method, Seeplex PneumoBacter ACE detection assay (Seeplex PB ACE), which simultaneously detects S. pneumoniae, M. pneumoniae, C. pneumoniae, L. pneumophila, H. influenzae, and B. pertussis We tested 2,137 nasopharyngeal swab and sputum specimens using both assays. For discordant Bordetella parapertussis and M. catarrhalis specimens, we also performed bidirectional sequencing. For S. pneumoniae, M. pneumoniae, C. pneumoniae, L. pneumophila, H. influenzae, and B. pertussis, which are detected by both NeoPlex RB-8 and Seeplex PB ACE, the positive and negative agreement between the two assays ranged from 91.7 to 100% (κ = 0.918 to 1). S. pneumoniae and H. influenzae were the most discordant targets and measured with higher sensitivity and specificity by NeoPlex RB-8 than Seeplex PB ACE. For Bordetella parapertussis and M. catarrhalis, which are not detected by Seeplex PB ACE, NeoPlex RB-8 sensitivity and specificity were >99%. Overall, NeoPlex RB-8 was highly comparable to Seeplex PB ACE, but NeoPlex RB-8 was more clinically accurate, with higher throughput and more convenience.

Case Series of All-Arthroscopic Treatment for Terrible Triad of the Elbow: Indications and Clinical Outcomes.

PURPOSE: To evaluate the results of all-arthroscopic treatment of the terrible triad of the elbow, a combination of elbow dislocation, radial head dislocation, and coronoid process fracture, and its complications. METHODS: We performed a retrospective review of consecutive patients with terrible triad who underwent all-arthroscopic treatment between January 2011 and December 2016. All-arthroscopic treatment was performed in the unstable elbows after manual reduction. Clinical evaluation was performed at least 2 years postoperatively. Patients with another fracture in the upper extremity and previous fracture of the affected elbow were excluded. A radial head fracture that was stable enough to reduce or involved less than 25% of the articular surface for partial excision and Regan-Morrey classification type I and type II coronoid process fractures were treated arthroscopically. Range of motion, radiologic outcomes, surgical complications, and the Mayo Elbow Performance Score were evaluated at the final follow-up. The Mann-Whitney test was used for statistical analysis. RESULTS: A total of 24 patients met the inclusion criteria, and the average age was 47.6 years. Coronoid process fractures were fixed in all patients, by use of Kirschner wires in 15 (62.5%) and pullout sutures in 9 (37.5%). Radial head fractures were treated using screw or K-wire fixation in 4 patients (16.7%); only the fragment of the fracture was resected in 11 patients (45.8%). In all 24 cases (100%), the lateral collateral ligaments were repaired. At the final follow-up, the mean flexion contracture angle was 4.8° ± 1.1° and the mean flexion angle was 132.5° ± 6.3°. Clinical scores were satisfactory, with a mean Mayo Elbow Performance Score of 93 points. However, nonunion of coronoid fractures was observed in 4 patients (16.7%). There was 1 case of pin-site irritation. CONCLUSIONS: All-arthroscopic treatment for the terrible triad can provide an excellent safety profile without the need for a large incision if the indications are met. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Second shot arterial phase to overcome degraded hepatic arterial phase in liver MR imaging.

OBJECTIVES: Second shot arterial phase (SSAP) imaging is an additional arterial phase image obtained by re-injecting a small amount of contrast medium after routine dynamic imaging in gadoxetic acid-enhanced liver MRI. We aimed to evaluate the feasibility and additional value of a SSAP image in gadoxetic acid-enhanced liver MRI. METHODS: One hundred seventy-two patients who underwent SSAP imaging after re-injection of 4 mL of contrast material after routine dynamic imaging (original) in gadoxetic acid-enhanced liver MRIs were included. Motion artifacts on arterial phase (AP) images were rated using a 5-point scale and were compared between the original AP images and SSAP images. We evaluated visual detection rates of arterial hypervascularity on the original AP and SSAP images and their subtraction images in patients with hypervascular hepatocellular carcinoma (HCC). RESULTS: The motion artifact of the SSAP images was significantly lower than that of the original AP images (mean score, 1.76 vs 2.06; p < 0.001). In particular, motion artifacts reduced significantly in the SSAP images of patients with substantial motion artifacts in their original AP images (2.28 vs 3.28; p < 0.001). Among the 30 HCC lesions showing hypervascularity on original AP images, only four (4/30, 13.3%) appeared hyperintense on SSAP images. However, subtraction images of SSAP clearly demonstrated arterial hypervascularity in all HCCs. CONCLUSION: SSAP images showed significantly fewer motion artifacts than the original AP images. Subtraction images of SSAP maintained the detectability of arterial hypervascularity, although SSAP images showed poor visual detection of arterial hypervascularity of HCC. KEY POINTS: • Arterial phase images obtained after a second injection of a small amount of contrast medium (second shot arterial phase [SSAP]) improved motion artifacts compared to the original AP images. • The motion artifacts improved significantly in the SSAP images of patients with substantial motion artifacts in their original AP images. • Subtraction images of SSAP demonstrated the arterial hypervascularity characteristic of HCC at a level comparable to that of the original AP image.

Newly Categorized Seromucinous Tumor of the Ovary: Magnetic Resonance Imaging Findings.

OBJECTIVE: The aim of this study was to describe magnetic resonance imaging findings of newly categorized ovarian seromucinous tumors. METHODS: We retrospectively reviewed the images of 29 patients with seromucinous tumor for the following factors: size, configuration, signal intensity (SI), and accompanying ovarian endometriosis. RESULTS: Thirty-two tumors (17 benign, 7 borderline, 8 carcinoma) were found on computed tomography or magnetic resonance imaging. Their mean size was 11.4 cm. Benign tumors appeared as unilocular or multilocular cystic masses. Borderline tumors and carcinomas appeared as complex cystic-solid masses. T2-weighted SI of the solid portion was hyperintense in borderline tumors and intermediate in carcinomas. Endometriosis was present in 18 tumors, and hemorrhage (on images) in 20. CONCLUSIONS: The imaging features of seromucinous tumors varied by tumor type. More than half of tumors were accompanied by endometriosis. High T2-weighted SI of the solid portion could be a specific feature of borderline tumors. It is hard to differentiate seromucinous carcinomas from other endometriosis-related carcinomas.

Annexin A2 Deficiency Exacerbates Neuroinflammation and Long-Term Neurological Deficits after Traumatic Brain Injury in Mice.

Our laboratory and others previously showed that Annexin A2 knockout (A2KO) mice had impaired blood-brain barrier (BBB) development and elevated pro-inflammatory response in macrophages, implying that Annexin A2 (AnxA2) might be one of the key endogenous factors for maintaining homeostasis of the neurovascular unit in the brain. Traumatic brain injury (TBI) is an important cause of disability and mortality worldwide, and neurovascular inflammation plays an important role in the TBI pathophysiology. In the present study, we aimed to test the hypothesis that A2KO promotes pro-inflammatory response in the brain and worsens neurobehavioral outcomes after TBI. TBI was conducted by a controlled cortical impact (CCI) device in mice. Our experimental results showed AnxA2 expression was significantly up-regulated in response to TBI at day three post-TBI. We also found more production of pro-inflammatory cytokines in the A2KO mouse brain, while there was a significant increase of inflammatory adhesion molecules mRNA expression in isolated cerebral micro-vessels of A2KO mice compared with wild-type (WT) mice. Consistently, the A2KO mice brains had a significant increase in leukocyte brain infiltration at two days after TBI. Importantly, A2KO mice had significantly worse sensorimotor and cognitive function deficits up to 28 days after TBI and significantly larger brain tissue loss. Therefore, these results suggested that AnxA2 deficiency results in exacerbated early neurovascular pro-inflammation, which leads to a worse long-term neurologic outcome after TBI.

Risk Factors for Recurrence of Anterior-Inferior Instability of the Shoulder After Arthroscopic Bankart Repair in Patients Younger Than 30 Years.

PURPOSE: To identify the risk factors for recurrent instability after arthroscopic Bankart repair and evaluate the recurrence rate and functional outcomes. METHODS: A retrospective review was performed of patients with anterior-inferior shoulder instability who underwent arthroscopic Bankart repair between 2008 and 2014. Patients below 30 years of age who were available for follow-up at least for 2 years were sorted into 2 groups according to the presence of recurrent instability. Furthermore, statistical analysis by binary logistic regression analysis included the significance of various risk factors including gender, demographic factors, number of preoperative dislocations, time interval between the first dislocation and the surgery (shorter than 6 months or not), generalized hyperlaxity, concomitant injury, bony Bankart, and off-track lesion. The functional outcomes were assessed with the Rowe and Walch-Duplay scores. RESULTS: A total of 170 shoulders were included (without-recurrence group: 138, recurrent group: 32). The overall postoperative recurrent instability rate was 18.8%. SLAP repair, interval closure, and capsular plication were performed when necessary. However, these additional procedures were not influenced by recurrence (P = .37). The 2 groups showed significant differences in the number of preoperative dislocations (P = .048; adjusted odds ratio [OR] 2-5 times, 6.41; more than 5 times, 8.77), time interval between the first dislocation and surgery (P = .003, adjusted OR 5.62), and off-track Hill-Sachs lesion (P = .04, adjusted OR 4.31). There was significant improvement in the mean Rowe and Walch-Duplay scores at 2 years postoperatively (P < .001 in both cases), but the mean scores were lower in the group with recurrence than in the group without (P = .021 and .014, respectively). CONCLUSIONS: The overall results suggest that surgery within 6 months of the first dislocation should be considered, with meticulous attention in patients with a high number of preoperative dislocations or off-track Hill-Sachs lesions. LEVEL OF EVIDENCE: Level III, retrospective case-control study.

Two-stage revision of infected shoulder arthroplasty using prosthesis of antibiotic-loaded acrylic cement: minimum three-year follow-up.

PURPOSE: This study aimed to evaluate the clinical outcomes and persistent infection rate of two-stage revision of infected shoulder arthroplasty. METHODS: We enrolled 12 patients who developed an infection after undergoing shoulder arthroplasty between January 2009 and January 2014. They underwent a two-stage revision with PROSTALAC implantation and shoulder re-implantation in the first- and second-stage surgery, respectively. The mean follow-up period was 40.88 months (range, 36-52 months). After the second-stage re-implantation, clinical scores, erythrocyte sedimentation rate, as well as C-reactive protein level were evaluated, and the presence of re-infection and complications were analyzed. RESULTS: Infection was improved in all the cases after PROSTALAC insertion. The mean range of motion of forward elevation, external rotation, and internal rotation at the final follow-up after the second-stage re-implantation were 81.67°, 40.42°, and 16.67° (vertebral level), respectively. The mean visual analog scale score improved from 7.08 points before surgery to 2.33 points after surgery. The Modified American Shoulder and Elbow Surgeons score improved from 32.25 before surgery to 64.17 after surgery (P < 0.05). The Constant shoulder score also improved from 30.92 before surgery to 66.08 after surgery (P < 0.05). Infection had not recurred until the final follow-up. However, dislocation and separation of components were found in two patients who needed a structural allograft because of segmental bone defects. CONCLUSION: Using PROSTALAC in two-stage revision arthroplasty is effective for infection control and produced good clinical outcomes after second-stage shoulder re-implantation. However, cases involving segmental bone defects require additional precautions in maintaining the appropriate tension and height to prevent complications.

Washout appearance in Gd-EOB-DTPA-enhanced MR imaging: A differentiating feature between hepatocellular carcinoma with paradoxical uptake on the hepatobiliary phase and focal nodular hyperplasia-like nodules.

PURPOSE: To identify the most reliable imaging features for differentiating hepatocellular carcinoma with paradoxical uptake on the hepatobiliary phase (HCCpara ) from focal nodular hyperplasia (FNH)-like nodules using Gd-EOB-DTPA-enhanced MRI. MATERIALS AND METHODS: This was a retrospective study. Twenty patients with HCCpara and 21 patients with FNH-like nodules were included. The following MRI features were evaluated using 3.0 Tesla unit by two radiologists: signal intensity (SI) on T1-, T2-, and diffusion-weighted imaging (DWI), arterial enhancement pattern, washout appearance on the portal venous phase (PVP) and/or transitional phase (TP), uptake pattern on the hepatobiliary phase (HBP), "T2 scar," "EOB scar," and chemical shift on in- and out-of-phase images. Multivariate logistic regression analysis was performed to assess MRI features for prediction of HCCpara . RESULTS: Compared with FNH-like nodules, HCCpara had significantly more frequent heterogeneous T1 SI (P < 0.0001), T2 hyperintensity (P = 0.032), heterogeneous arterial enhancement (P < 0.0001), washout appearance on the PVP and/or TP (P < 0.0001), heterogeneous uptake on the HBP (P < 0.0001), absence of "EOB scar" (P < 0.0001), and hyperintensity on DWI (P = 0.004). Multivariate logistic regression analysis revealed washout appearance as the only independent imaging feature associated with HCCpara (odds ratio, 7.019; P = 0.042). Washout appearance also showed the best diagnostic performance with a sensitivity of 90% and a specificity of 100%. CONCLUSION: Washout appearance on the PVP and/or TP is the most reliable imaging feature for differentiating HCCpara from FNH-like nodules. LEVEL OF EVIDENCE: 3 J. MAGN. RESON. IMAGING 2017;45:1599-1608.

Retrospective Comparative Analysis of Elbow Arthroscopy Used to Treat Primary Osteoarthritis With and Without Release of the Posterior Band of the Medial Collateral Ligament.

PURPOSE: To evaluate the clinical and functional outcomes of arthroscopic debridement arthroplasty with the release of the posterior band of the medial collateral ligament in patients with primary osteoarthritis. METHODS: We evaluated 43 patients treated with arthroscopic debridement arthroplasty for elbow osteoarthritis from February 2006 to February 2014. In group A (n = 19), the posterior band of the medial collateral ligament was released, and in group B (n = 24), it was not released. The mean follow-up period in groups A and B was 55.4 months (range, 24-100 months) and 62.2 months (range, 24-103 months), respectively. Clinical results were evaluated by measuring the preoperative and postoperative range of motion (ROM) of the elbow, visual analog scale score, and Mayo Elbow Performance Score. RESULTS: Both groups showed significant improvement in clinical outcome (visual analog scale and Mayo Elbow Performance Score) at the final follow-up compared with preoperative evaluation (group A, P = .009 and .013, respectively; group B, P = .015 and .008, respectively). Group A showed significant improvement in increased flexion at 6 months of follow-up (P = .043). However, there was no statistically significant difference in postoperative ROM and clinical results between the 2 groups at the final follow-up (P = .482). CONCLUSIONS: Arthroscopic debridement arthroplasty with the release of the posterior band of the medial collateral ligament was associated with improved flexion at the 6-month postoperative follow-up, but no significant difference between the groups was observed at the final follow-up. Therefore, the additional release of the posterior band of the medial collateral ligament may be unnecessary for improving postoperative ROM. LEVEL OF EVIDENCE: Level IV, therapeutic case series.

Is the arthroscopic suture bridge technique suitable for full-thickness rotator cuff tears of any size?

PURPOSE: The purpose of this study was to compare functional outcomes and tendon integrity between the suture bridge and modified tension band techniques for arthroscopic rotator cuff repair. METHODS: A consecutive series of 128 patients who underwent the modified tension band (MTB group; 69 patients) and suture bridge (SB group; 59 patients) techniques were enrolled. The pain visual analogue scale (VAS), Constant, and American Shoulder and Elbow Surgeons (ASES) scores were determined preoperatively and at the final follow-up. Rotator cuff hypotrophy was quantified by calculating the occupation ratio (OR). Rotator cuff integrity and the global fatty degeneration index were determined by using magnetic resonance imaging at 6 months postoperatively. RESULTS: The average VAS, Constant, and ASES scores improved significantly at the final follow-up in both groups (p < 0.05 for all scores). The retear rate of small-to-medium tears was similar in the modified tension band and suture bridge groups (7.0 vs. 6.8%, respectively; p = n.s.). The retear rate of large-to-massive tears was significantly lower in the suture bridge group than in the modified tension band group (33.3 vs. 70%; p = 0.035). Fatty infiltration (postoperative global fatty degeneration index, p = 0.022) and muscle hypotrophy (postoperative OR, p = 0.038) outcomes were significantly better with the suture bridge technique. CONCLUSION: The retear rate was lower with the suture bridge technique in the case of large-to-massive rotator cuff tears. Additionally, significant improvements in hypotrophy and fatty infiltration of the rotator cuff were obtained with the suture bridge technique, possibly resulting in better anatomical outcomes. The suture bridge technique was a more effective method for the repair of rotator cuff tears of all sizes as compared to the modified tension band technique. LEVEL OF EVIDENCE: Retrospective Cohort Design, Treatment Study, level III.

Assessing Lightning and Wildfire Hazard by Land Properties and Cloud to Ground Lightning Data with Association Rule Mining in Alberta, Canada.

Hotspot analysis was implemented to find regions in the province of Alberta (Canada) with high frequency Cloud to Ground (CG) lightning strikes clustered together. Generally, hotspot regions are located in the central, central east, and south central regions of the study region. About 94% of annual lightning occurred during warm months (June to August) and the daily lightning frequency was influenced by the diurnal heating cycle. The association rule mining technique was used to investigate frequent CG lightning patterns, which were verified by similarity measurement to check the patterns' consistency. The similarity coefficient values indicated that there were high correlations throughout the entire study period. Most wildfires (about 93%) in Alberta occurred in forests, wetland forests, and wetland shrub areas. It was also found that lightning and wildfires occur in two distinct areas: frequent wildfire regions with a high frequency of lightning, and frequent wild-fire regions with a low frequency of lightning. Further, the preference index (PI) revealed locations where the wildfires occurred more frequently than in other class regions. The wildfire hazard area was estimated with the CG lightning hazard map and specific land use types.

The Effect of Reduced Graphene Oxide-Coated Biphasic Calcium Phosphate Bone Graft Material on Osteogenesis.

This study was conducted to evaluate the effect of biphasic calcium phosphate (BCP) coated with reduced graphene oxide (rGO) as bone graft materials on bone regeneration. The rGO-coated BCP bone graft material was fabricatied by mixing rGO and BCP at various concentrations. The surface charge of rGO-coated BCP was measured to be -14.43 mV, which formed a static electrostatic interaction. Cell viabilities were significantly diminished at higher concentrations of ≥100 µg/mL. The calvarial defects of 48 rats were implanted rGO-coated BCPs at a weight ratio of 2:1000 (rGO2), 4:1000 (rGO4), and 10:1000 (rGO10), repectively. BCP was used as a control group. The micro-CT and histological analysis were performed to evaluate new bone formation at 2 and 8 weeks after surgery. The results showed that the new bone volume (mm³) was significantly higher in the experimental groups than in the control group. Histological analysis showed that new bone areas (%) were significantly higher in the rGO2 and rGO10 than in the control, and significantly higher in rGO4 than in the rGO2 and rGO10. Conclusively, the rGO-coated BCP was found to be effective on osteogenesis and the concentration of the composite was an important factor.

Intravoxel incoherent motion magnetic resonance imaging to predict vesicoureteral reflux in children with urinary tract infection.

OBJECTIVES: To compare the diffusion parameters of intravoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI) between the "reflux" and the "non-reflux" kidneys, and to evaluate the feasibility of using IVIM DWI to predict vesicoureteral reflux (VUR) in children with a urinary tract infection (UTI). METHODS: Eighty-three kidneys from 57 pediatric patients with a UTI were classified into "reflux" and "non-reflux" groups according to voiding cystourethrography (VCUG) results. The apparent diffusion coefficient (ADC), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and perfusion fraction (PF) were measured and compared in the renal pelvis of both groups. Four indices (D*/ADC, PF/ADC, D*/D, and PF/D) were calculated and receiver operating characteristic (ROC) curve analyses were performed. RESULTS: VURs were detected on VCUG in 21 kidneys. PF and D* were significantly higher in the "reflux" group than in the "non-reflux" group. The indices were all significantly higher. The PF/D index showed the best diagnostic performance in predicting VUR in children with UTI (Az = 0.864). CONCLUSION: PF and D* were significantly higher in the "reflux" kidney than in the "non-reflux" kidney. Our new index (PF/D) could prove useful for predicting VUR. KEY POINTS: • IVIM DWI is both radiation-free and contrast media-free. • IVIM DWI index is easily calculated by combining diffusion parameters. • IVIM DWI may help predict VUR in children with UTI. • PF is significantly higher in the "reflux" than the "non-reflux" kidneys. • A new VUR index, PF/D could prove useful for predicting VUR.

Arthroscopic proximal versus open subpectoral biceps tenodesis with arthroscopic repair of small- or medium-sized rotator cuff tears.

PURPOSE: The study was aimed to compare arthroscopic proximal biceps tenodesis and open subpectoral biceps tenodesis in repair of small or medium rotator cuff tears. METHODS: Eighty-five patients underwent biceps tenodesis with arthroscopic repair of a rotator cuff tear, and 66 patients were followed for median of 26.8 (18-42) months with ultrasonography were reviewed. The arthroscopic biceps tenodesis group included 34 cases, and the open subpectoral biceps group included 32 cases. Patients were evaluated using visual analogue scale (VAS), American Shoulder and Elbow Surgeons (ASES), and constant scores. Rotator cuff repair and fixation of the biceps tendon were assessed by ultrasonography. Fixation failure and degree of deformity were evaluated by the pain in the bicipital groove and biceps apex distance (BAD). RESULTS: VAS score and tenderness at the bicipital groove decreased significantly in the open subpectoral group at 3 months postoperative. In both groups, the range of motion, ASES score, and constant score increased significantly (P < 0.05). Rotator cuff retear occurred in three cases (8.8 %) in the arthroscopic group and two cases in the open subpectoral group (6.2 %). There was no significant difference in BAD between the two groups. CONCLUSION: There was no difference between open subpectoral tenodesis and arthroscopic proximal tenodesis at the time of the final follow-up; however, open subpectoral tenodesis showed encouraging results at 3-month follow-up. This early result of subpectoral tenodesis was related to removing most part of biceps tendinitis and using intra-bicipital groove tenodesis technique. LEVEL OF EVIDENCE: III.