Validation of the modified CT criteria for identifying non-adenomas.

PURPOSE: Although adrenal computed tomography (CT) percentage washout is a potentially powerful imaging technique for differentiating adrenal adenomas from non-adenomas, its application to non-adenomas can be problematic. Recently, modified criteria for diagnosing pheochromocytomas using adrenal CT were developed based on data from 199 patients with surgically proven pheochromocytomas and adenomas. However, these criteria have not been thoroughly validated. The purpose of this study was to validate the performance of the modified criteria for diagnosing non-adenomas including pheochromocytomas. METHODS: The conventional and modified criteria were applied to 266 patients from two cohorts who had surgically proven lipid-poor adenomas (155/266, 58.3%) and non-adenomas (111/266, 41.7%) and underwent adrenal CT. Two radiologists calculated the attenuation on each dynamic phase and percentage washout of adrenal masses. The final assessments based on the conventional and modified criteria were categorized into adenomas or non-adenomas. The diagnostic performance of each criterion for diagnosing non-adenomas was evaluated using the area under the receiver operating characteristic curve (AUC). False negatives and positives were also compared. RESULTS: The AUC for the diagnosis of non-adenomas was 0.806 for conventional criteria and 0.858 for modified criteria (p = 0.047). The false-negative rate of conventional criteria for the diagnosis of non-adenomas was 29.7%. Use of modified criteria could have reduced the false-negative rate by to 7.2%. The false-positive rate increased from 9% to 21.3% when using the modified criteria. CONCLUSION: The utilization of modified criteria has the potential to identify additional non-adenomas that would otherwise be misdiagnosed as adenomas using conventional criteria alone.

Abnormalities of the pericruciate fat pad: Correlations with the location and severity of chondral lesions of the knee.

PURPOSE: The aim of this study was to evaluate the relationship between the grade of signal change of the pericruciate fat pad (PCFP) and the location and severity of cartilage alterations in the knee on magnetic resonance imaging (MRI). MATERIALS AND METHODS: This retrospective study included 234 patients (M:F = 96:138, mean: 51 years) who underwent knee MRI. Two experienced musculoskeletal radiologists assessed any PCFP alterations (as grades 0-3) and chondral lesions using the modified Outerbridge grade (as grades 0-4). Bone marrow lesions (BMLs), meniscal status, anterior cruciate ligament alterations, and effusion-synovitis were also evaluated on the MRI. The relationships between PCFP alteration and MR findings (including the grade of chondral lesion) were evaluated. RESULTS: Signal changes in the PCFP were detected in 150 cases by Reader 1 (grade 0, 67 cases; grade 1, 53 cases; grade 2, 21 cases; grade 3, 9 cases) and in 154 cases by Reader 2 (grade 0, 59 cases; grade 1, 61 cases; grade 2, 24 cases; grade 3, 10 cases). The grade of PCFP signal change was statistically significantly correlated with the grade of the chondral lesion of the medial femoral condyle (MFC) (p = 0.029 and p = 0.003, respectively) and the medial tibial plateau (MTP) (p = 0.045, p = 0.002, Readers 1 and 2, respectively). The grade of PCFP signal change was significantly correlated with the grade of the BMLs of the MFC, MTP, and lateral femoral condyle (p < 0.05) for both readers. PCFP alteration was related to effusion-synovitis and tears of the medial meniscus. CONCLUSIONS: The grade of PCFP signal change was correlated with the severity of the cartilage alteration in the medial compartment of the knee joint and was also correlated with BMLs in the medial compartment, medial meniscal tears, and synovitis. Therefore, signal change in the PFCP seen on MRI can be an additional clue of the presence of osteoarthritis in the knee, particularly in the medial compartment.

Aponeurotic expansion of the supraspinatus tendon and concomitant shoulder pathologies.

OBJECTIVES: We investigated the correlation of aponeurotic expansion of the supraspinatus tendon (AESST) with shoulder pathologies such as long head of biceps tendon (LHB), supraspinatus tendon (SST), and subscapularis tendon (SSc). METHODS: We retrospectively evaluated 47 healthy patients and 163 patients with shoulder symptoms from August 2014 to March 2021. First, the presence of AESST was evaluated based on Moser et al.'s classification. Second, the presence of abnormal findings of including LHB tendinitis, LHB subluxation, SST tendinitis, SST tear, SSc tendinitis, and SSc tendon tear was evaluated. We analyzed the prevalence and type of AESST between the two study groups and the relationship between abnormal findings and the presence of AESST. RESULTS: The prevalence of AESST for readers 1 and 2 was 26.1% and 30.4% in the asymptomatic group, respectively, and 22.8% and 31.3% in the symptomatic group. Type 1 was most common (17.3-23.9%) followed by types 2a and 2b. There were no significant differences in the distribution of aponeurosis type between the two groups. In the AESST-positive groups, 45.9% and 47.1% had SST tears on examination by readers 1 and 2, respectively, whereas only 26.4% and 27.9% had SST tears in the AESST-negative group suggesting AESST is associated with SST tear. The odds ratio for SST tear in the presence of AESST was 2.370 and 2.294 (readers 1 and 2). CONCLUSIONS: There is an association between SST tears and the presence of AESST. KEY POINTS: • We evaluated the prevalence of aponeurotic expansion of the supraspinatus tendon (AESST) on MR imaging by type in both symptomatic and asymptomatic groups. • We investigated the correlation of AESST with shoulder pathologies such as biceps tendon and supraspinatus tendon tears. • There is an association between SST tears and the presence of AESST. • Radiologists should be aware of the risk of rotator cuff pathology if AESST is detected.

Intra- and extra-capsular ganglia at the gastrocnemius origin and association with meniscal tears and severity of osteoarthritis of the knee joint.

BACKGROUND: The association between size of ganglia or type of ganglia (intra-articular or extra-articular) and meniscal tears or severity of the osteoarthritis (OA) is not evaluated. PURPOSE: To evaluate the prevalence, size, and location of intra- and extra-capsular ganglia at the gastrocnemius origin and to assess their associations with meniscal injury and grades of OA. MATERIAL AND METHODS: This study included 301 consecutive patients who had knee pain and had undergone magnetic resonance imaging (MRI) of the knee. We evaluated presence of ganglia at the gastrocnemius muscle origin site and diagnosed whether it was an intra-capsular located or mixed-capsular located (intra-capsular and extra-capsular) and then measured the diameter of each ganglion. After two weeks, we evaluated whether articular cartilage injury existed. The presence of a meniscal tear was also recorded. RESULTS: A total of 186 patients (93%) had intra- and extra-capsular ganglia. Intra-capsular ganglia were found in 183 cases (91%) and mixed-capsular ganglia were found in 16 cases (8%). In cases with intra- and extra-capsular ganglia, more meniscal tears were found (P = 0.029). Intra-capsular ganglia showed more meniscal tears (P = 0.021). Intra-capsular ganglia were more likely to have high-grade OA (P = 0.043). Patients who had a meniscal tear displayed larger-sized ganglia, especially of the intra-capsular type (P = 0.044). CONCLUSION: Patients with intra- and extra-capsular ganglia, especially of the intra-capsular type, are more likely to have meniscal injury and more severe OA. Patients with a meniscal tear or OA are more likely to have larger intra- and extra-capsular ganglia, especially of the intra-capsular type.

Cyclops lesions associated with both bundles and selective bundle repair of the anterior cruciate ligament.

BACKGROUND: The remnant of a ruptured anterior cruciate ligament (ACL) can increase the risk of impingement or a cyclops lesion, which can increase challenges to proper tunnel placement. PURPOSE: To evaluate the prevalence of cyclops lesions after ACL reconstruction and to assess the difference in the incidence of cyclops lesions between single-bundle repair and selective bundle repair of the ACL. MATERIAL AND METHODS: This retrospective study included 151 patients who were diagnosed with an ACL tear after knee joint magnetic resonance imaging (MRI) who underwent ACL reconstruction surgery. MRI diagnosis of cyclops lesion formation was made if a soft-tissue mass was seen anteriorly in the intercondylar notch near the tibial insertion of the reconstructed ACL, based on sagittal T2-weighted (T2W) imaging. The size of the cyclops lesions was recorded as the largest diameter on the sagittal T2W imaging. RESULTS: A cyclops lesion was detected in 74 (38.5%) cases. Cyclops lesions were detected more frequently in cases with single-bundle repair of the ACL, but the results were not statistically significant (P = 0.609). Compared with selective bundle repair, cyclops lesions had a significantly higher prevalence in the posterolateral (PL) bundle repair than in the anteromedial (AM) bundle repair (P = 0.027) based on MR images at 6-12 months after surgery. CONCLUSION: The incidence of cyclops lesions did not differ significantly in single-bundle repair and selective bundle repair of ACL. However, selective PL bundle repair of the ACL showed a significantly increased incidence of cyclops lesions compared with selective AM bundle repair.

Ultrasonographic and strain elastographic features of epidermal cyst according to body location.

BACKGROUND: There are not many studies on the differences of ultrasound (US) findings between epidermal cysts (ECs) located in the trunk and those in the extremities. PURPOSE: To compare the sonographic findings of ECs according to location in the body (trunk vs. extremity) and evaluated the feasibility of strain elastography (SE). MATERIAL AND METHODS: This is a retrospective study of 76 patients with surgically confirmed non-ruptured EC who underwent US including SE. The US analyses included size, shape, ratio of depth to length (DLR), involvement of more than half the dermis, "submarine sign," and SE characters of each lesion. SE findings were assigned into four grades based on elasticity. RESULTS: The submarine sign was more significantly observed in ECs located in the trunk versus extremities (P value = 0.004 and 0.035, respectively). Truncal lesions were significantly more likely to possess an ovoid shape (P < 0.05) and exhibited higher DLR (P < 0.05). There were more cases with low elasticity according to SE (grade 3 or 4) compared to high elasticity (grade 1 or 2). However, we did not observe significant differences between the two locations (P > 0.05). More-than-half signs also did not exhibit a significant difference (P > 0.05). CONCLUSION: The submarine sign, ovoid shape, and tall lesions (higher DLR) are common in the trunk. However, the degree of elasticity and number of more-than-half signs did not differ between the two groups.

Sonographic and elastographic findings after arthroscopic rotator cuff repair: a comparison with clinical results.

OBJECTIVE: We assessed the relationship between early postoperative clinical outcomes of arthroscopic rotator cuff repair (ARCR) and observations obtained by postsurgical ultrasound (US) and strain elastography (SE) of repaired supraspinatus tendons (SSTs). METHODS: This retrospective study included 42 cases in which the patient underwent ARCR followed by postoperative US and SE. The Korean Shoulder Scoring (KSS) system was used to assess preoperative and postoperative conditions. The thickness of the repaired SST and subdeltoid fluid was measured by US. SE scores were classified into four grades (1 to 4) according to elasticity of repaired SST. In addition, SE scores were divided into two groups: soft (SE scores of 1 and 2) and hard (SE scores of 3 and 4). The relationship between clinical outcomes and US parameters and SE scores was determined by KSS. RESULTS: Postoperative SE scores observed by two readers correlated significantly with function (p = 0.021 and p = 0.021, respectively) and muscle strength (p = 0.008 and p = 0.015, respectively). SE scores were significantly correlated with a difference value of muscle strength of KSS scores (p = 0.002 and p = 0.014). In a comparison of hard and soft groups of repaired SSTs, function (p = 0.008 and p = 0.010, respectively) and muscle strength (p = 0.002 and p = 0.014, respectively) in postoperative KSS scores were statistically higher in the hard SE scores than the soft SE scores. The difference value of function (p = 0.021 and p = 0.021,) and muscle strength (p = 0.008 and p = 0.015) of KSS scores was significantly higher in the hard SE scores. CONCLUSIONS: Postoperative SE scores of repaired tendons correlated significantly with muscle strength and function after ARCR. Postoperative US images including thickness of repaired tendon and subdeltoid fluid did not correlate with clinical outcome. ADVANCES IN KNOWLEDGE: SE evaluations of repaired SST may provide important information about postoperative muscle strength and function.

To Assess Whether Lee's Grading System for Central Lumbar Spinal Stenosis Can Be Used as a Decision-Making Tool for Surgical Treatment.

Purpose: To evaluate the correlation between Lee's grades and surgical intervention for central lumbar spinal stenosis (CLSS) and to assess whether this grading system can be used as a decision-making tool for the surgical treatment of this condition. Materials and Methods: This retrospective study included 290 patients (M:F = 156:134; mean age, 46 ± 16 years). Radiologists assessed the presence and grade of CLSS at the stenosis point according to Lee's grading system, in which CLSS is classified into four grades according to the shape of the cauda equina. Correlation coefficients (rs ) between Lee's grades and the operation were calculated with Spearman rank correlation. Results: Among the operated patients, grade 2 was the most commonly assigned grade (50%-58%), grade 3 was less common (35%), and grade 0 was the least common (2%-3%). Among the non-operated patients, grade 1 was the most common (63%-65%), grade 0 was less common (15%-16%), and grade 3 was the least common (8%). The distribution of grades differed between the operated and non-operated groups (p < 0.001). Less than 25% of patients who underwent surgery were assigned grades 0 and 1, and more than 88% were assigned grades 2 and 3. A moderate correlation was found between the grade and surgical intervention (rs = 0.632 and rs = 0.583). Conclusion: Lee's grade was moderately correlated with surgical intervention. Lee's grading system can be a decision-making tool for the surgical treatment of CLSS.

Sonographic and Strain Elastographic Findings of a Clear Cell Hidradenoma that Looked Like an Epidermoid Tumor: A Case Report.

Clear cell hidradenoma (CCH) is a rare tumor of the sweat glands of eccrine or apocrine differentiation. It can occur anywhere in the body, but common sites of involvement are the head, face, trunk, and extremities. Although several reports have described sonographic findings of CCH, only one study on the axilla mentioned its strain elastographic findings. Here, we present a case of CCH in the right calf with its sonographic and strain elastographic findings in a tumor that looked like an epidermoid tumor.

The reproducibility of shear wave and strain elastography in epidermal cysts.

PURPOSE: This study evaluated epidermal cyst elasticity using multiple parameters of strain elastography (SE) and shear wave elastography (SWE) and assessed the reproducibility of each parameter. METHODS: This retrospective study included 73 patients with epidermal cysts who underwent SE and SWE. SE scores were classified as 1-4 according to elasticity. The strain ratio was evaluated using the elasticity ratio of lesions and adjacent subcutaneous fat tissue. For SWE, the shear wave velocity (m/s), elasticity (kPa) according to the Young modulus, velocity ratio, and elasticity ratio were evaluated. All values were measured twice. The reproducibility of SE and SWE measurements was assessed. The relationships among SE and SWE measurements were evaluated. RESULTS: The strain ratio on SE images showed good reproducibility (intra-class correlation coefficient [ICC]=0.789), and SE scores showed substantial reproducibility (kappa=0.753 and kappa=0.758 for readers 1 and 2, respectively). Moderate reproducibility was found for shear wave velocity and elasticity (ICC=0.750 and ICC=0.648, respectively), as well as for the shear wave velocity of the reference tissue and velocity ratio (ICC=0.747 and ICC=0.713, respectively). All SE scores were positively correlated with the strain ratio (P<0.001). The strain ratio in the second SE session was significantly correlated with the elasticity ratio and velocity ratio in the first SWE session (r=0.245, P=0.037; r=0.243, P=0.038, respectively). Other variables were not correlated. CONCLUSION: SE and SWE parameters of epidermal cysts showed moderate to good reproducibility. The strain ratio on SE showed good reproducibility and could provide relatively objective and consistent measurements of epidermal cyst elasticity.

Virtual non-contrast images from dual-energy CT angiography of the abdominal aorta and femoral arteries: comparison with true non-contrast CT images.

OBJECTIVES: To assess whether virtual non-contrast (VNC) computed tomography (CT) images acquired from dual-energy CT (DECT) have sufficient image quality to replace true non-contrast (TNC) CT images in CT angiography (CTAG). METHODS: This study enrolled 63 consecutive patients who underwent a CTAG that included a single-energy non-contrast scan, followed by a post-contrast DECT scan. Comparison of attenuation and noise between TNC and VNC images was made by drawing circular regions of interest (ROI) on a picture archiving and communication system (PACS) workstation within the aortic lumen at the levels of the renal arteries, the aortic bifurcation and right femoral artery. Mean attenuation and image noise (one standard deviation) were registered in Hounsfield units (HU). The VNC images were subjectively evaluated for artifacts such as subtraction of calcifications or architectural distortion based on TNC image as a standard of reference. RESULTS: Most attenuations of the VNCs were higher than TNC, except right femoral artery of reader 2. Most image noises of TNC were higher than VNC, except abdominal aorta in reader 1. In qualitative image analysis, mean scores of VNC according to the 5-point scale were 3.68 and 3.63 (reader 1 and reader 2, respectively) which mean good to excellent to diagnose. CONCLUSION: HUs and VNC image noises are different from TNC images in CTAG. VNC images have sufficient image quality to replace TNC images in the diagnosis of calcific lesions. ADVANCES IN KNOWLEDGE: VNC images acquired from DECT have image quality adequate to replace TNC images in the diagnosis of the calcific lesion on the CTAG. VNC images based on DECT can avoid excessive and unnecessary patient exposure to radiation during CTAG.

Attachment Type, Thickness, and Volume of the Posterior Meniscofemoral Ligament and Meniscal Pathology.

Several studies have investigated the relationship between the thickness of the posterior meniscofemoral ligament (pMFL) and the presence of a discoid meniscus. We investigated the correlation between meniscal pathology and anatomic features of pMFL such as attachment type, thickness, and volume. We retrospectively evaluated 191 patients who underwent knee MRI. MR images were reviewed to assess the attachment type of the pMFL on the medial femoral condyle (high vs. low), the thickness of the pMFL, and the presence of a meniscal tear or a discoid meniscus. The pMFL volume was quantified by using three-dimensional (3D) segmentation software. The relationship between the frequency of medial or lateral meniscal tear and anatomic features of pMFL were analyzed using Chi-square, Fisher's exact, or Mann-Whitney U test. High type pMFLs had significantly greater thickness and volume than low type pMFLs (p < 0.001). Patients with degenerative lateral meniscal tear had significantly higher thickness and volume of the pMFL than patients with intact lateral meniscus (p < 0.05). The pMFL thickness and volume were not significantly related to traumatic lateral meniscal tear, medial meniscal tear, and discoid meniscus. High type pMFLs tended to be thicker and larger than low type pMFLs and higher thickness and volume of the pMFL was significantly related to the degenerative lateral meniscal tear. However, the attachment type of the pMFL itself was not significantly related to the lateral meniscal tear as well as the medial meniscal tear.

Protruding anterior medial meniscus and posterior tibial translation as secondary signs of complete and partial posterior cruciate ligament tear.

OBJECTIVE: To evaluate whether measurement of protruding anterior meniscus in the medial compartment (PAMM) and posterior tibial translation (PTT) can be used as a secondary sign of posterior cruciate ligament (PCL) tear for differential diagnosis of partial or complete tear. METHODS: 21 cases with complete PCL tear, 35 cases with partial PCL tear, and 55 normal cases were reviewed in this retrospective study. PTT and PAMM were measured from the MR images associated with each case. Non-parametric data were evaluated using the Kruskal-Wallis test and the Mann-Whitney U-test with Bonferroni correction to compare differences among the three groups: complete tear, partial tear, and controls. RESULTS: There were significant differences in the median values of PAMM among the three groups, and with PAMM increasing as the grade of PCL injury increased. However, there were no significant differences in median PTT among the three groups. Median PAMM in the partial and complete tear groups was significantly higher than in subjects without PCL rupture (adjusted p-value <0.05). Although median PAMM in subjects in the complete tear group tended to be higher than in those with a partial tear, this difference was not statistically significant (adjusted p-values ≥0.418). CONCLUSION: PAMM is more useful finding than PTT and can predict PCL tear with or without posterior instability. However, PAMM cannot differentiate partial tear and complete tear of the PCL. ADVANCES IN KNOWLEDGE: PAMM is more useful finding than PTT and can predict PCL tear with or without posterior instability. However, PAMM cannot differentiate partial tear and complete tear of the PCL.

Prevalence of anterolateral ligament injuries and lateral meniscus tear on MR imaging in patients with both-bundle tear vs. selective bundle incomplete tear of the anterior cruciate ligament.

OBJECTIVES: We investigated the prevalence of anterolateral ligament (ALL) injury and lateral meniscus (LM) tear in cases with both-bundle tear and selective bundle incomplete tear of the anterior cruciate ligament (ACL). METHODS: A total of 174 cases of magnetic resonance (MR) images that had an ACL tear and underwent arthroscopic ACL reconstruction were retrospectively reviewed. ACL injury was classified into both bundle, anteromedial bundle, and posterolateral bundle (PL) on arthroscopic finding. The ALL was divided into three portions: femoral, meniscal, and tibial. ALL injury was scored into three groups: grade 0 is intact; grade 1 is stranding and edema surrounds the expected location of the ALL; grade 2 is clear discontinuity of the ALL consistent with rupture. Traumatic LM tear was also assessed on MR images. RESULTS: The total prevalence of ALL injury was 36.2% (reader 1) and 42.0% (reader 2). ALL injury was statistically related to the selective bundle tear (p = 0.002 and 0.004, readers 1 and 2). PL bundle tear was significantly correlated with the ALL injury (p value < 0.001, readers 1 and 2, both). The location and grade of ALL injury were not significantly correlated with the type of ACL injury. LM tear was not significantly related to the types of ACL tear (p = 0.208 and 0.907, readers 1 and 2) and ALL injury (p value = 0.096 and 0.383, readers 1 and 2). CONCLUSIONS: ALL injury was significantly related to the PL bundle tear of the ACL. LM tear was not significantly correlated with the types of ACL injury and ALL injury. KEY POINTS: • Anterolateral ligament (ALL) injury was significantly related to the posterolateral bundle (PL) tear of the anterior cruciate ligament (ACL). • Lateral meniscus (LM) tear was not significantly correlated with the types of ACL injury and ALL injury. • Clinicians and radiologists should be aware of these relationships and scrutinize ALL injury in cases with PL bundle tears, even with an incomplete ACL injury.

Wedging of vertebral bodies at the thoracolumbar spine in healthy individuals on whole body MRI screening: correlation with disc degeneration and disc herniation.

BACKGROUND: There have been no reports on the relationship between wedging of vertebral bodies at the thoracolumbar spine and disc herniation in healthy individuals on magnetic resonance imaging (MRI). PURPOSE: To investigate the degree of wedging of vertebral bodies at the thoracolumbar spine in healthy individuals who underwent whole-body (WB) MRI. We also assessed the correlation between wedging and adjacent disc pathology. MATERIAL AND METHODS: This retrospective study comprised 200 healthy patients who underwent WB MRI as part of a regular health check from January 2019 to February 2019. We measured anterior and posterior vertical heights of each vertebral body between T10 and L2. The ratio of anterior height to posterior height (APR) was calculated, and we evaluated disc degeneration or disc herniation using WB MRI. RESULTS: The APR of T10 was significantly higher than at the other levels (P < 0.05), and the APR of L1 was significantly lower (P < 0.05). Men had a significantly smaller APR than women at T12 to L2 (P < 0.05). Regarding the relationship between APR and disc degeneration, the group without disc degeneration had a higher APR, with statistical significance at T12, L1, and L2. Regarding the relationship between APR and disc herniation, the group without disc herniation had a higher APR, with statistical significance at T11, T12, L1, and L2. CONCLUSION: Wedging of vertebral bodies is most prominent at L1. Although the values were statistically significant only at some levels, the patients with disc degeneration or herniation had more prominent wedge deformity of thoracolumbar spine.

Usefulness of strain elastography in the differential diagnosis of ruptured epidermal cyst and superficial abscess.

PURPOSE: The aim of this study was to evaluate the usefulness of strain elastography (SE) in the differential diagnosis of ruptured epidermal cyst and superficial abscess. METHODS: This retrospective study included 34 patients with ruptured epidermal cysts and 17 patients with superficial abscesses who underwent ultrasonography (US) including SE. The SE characteristics were classified into four grades (1 to 4) according to elasticity. The largest length and height of the lesion and their ratio were evaluated on the US images. Involvement of more than half of the depth of the dermis and the presence of the submarine sign were assessed. RESULTS: The inter-reader agreement of US and SE findings showed excellent or almost perfect agreement. The height, length, ratio of height to length, and more-than-half-depth sign did not significantly differ between ruptured epidermal cysts and superficial abscesses for either reader (reader 1, P=0.071, P=0.129, P=0.806, and P=0.102, respectively; reader 2, P=0.173, P=0.053, P=0.669, and P=0.060, respectively). The submarine sign was significantly more frequent in ruptured epidermal cysts than in superficial abscesses (both readers, P<0.001). The difference in SE scores between ruptured epidermal cysts and superficial abscesses, which are harder than ruptured epidermal cysts, was statistically significant (reader 1, P=0.046; reader 2, P=0.028). CONCLUSION: The SE score and submarine sign may be useful characteristics for distinguishing ruptured epidermal cyst from superficial abscess.

Association between joint effusions and concomitant structural injuries (tendinitis and structural injury) on MRI in ankle trauma without fracture.

BACKGROUND: The evaluation of correlations among joint effusion, ligament injuries, tenosynovitis and osteochondral lesion of talus (OLT) in the ankle joint is important for developing a treatment plan and predicting prognosis. PURPOSE: To evaluate correlations among tibiotalar (anterior) and talocalcaneal (posterior) joint effusion, tenosynovitis of major flexor tendons, ligaments, and OLT in a group of patients with ankle trauma. MATERIAL AND METHODS: This retrospective study included 101 patients with ankle trauma who underwent magnetic resonance imaging. Two radiologists assessed the presence and amount of effusion in the tibiotalar and talocalcaneal joints from grade 0 to 2, according to the amount of capsular distension. Concomitant structural injuries were assessed in the tibialis posterior (TP), flexor digitorum longus, flexor hallucis longus, and peroneus tendons, and the anterior talofibular ligament, calcaneofibular ligament, anteroinferior tibiofibular ligament, posteroinferior tibiofibular ligament, and OLT. RESULTS: The proportion of anterior and posterior joint effusion according to grade was 67.3% for anterior joint effusion grade 0, 22.8% for grade 1, and 9.9% for grade 2; for posterior joint effusion, grade 0 was 74.2%, grade 1 was 22.8%, and grade 2 was 3.0%. We found statistically significant correlations between posterior joint effusion and tenosynovitis of TP (P < 0.05) and between posterior joint effusion and OLT (P < 0.05). CONCLUSION: Posterior joint effusion is correlated with TP injury and OLT; however, tendon injuries have no correlation with other structural injuries of the ankle joint in a general population with ankle trauma.

Erratum to "Effects of Ammonium Chloride on Ozone-induced Airway Inflammation: the Role of Slc26a4 in the Lungs of Mice".

This corrects the article on p. e272 in vol. 35, PMID: 32808511.

Determining the Target Population That Would Most Benefit from Screening for Hepatic Fibrosis in a Primary Care Setting.

Due to its high prevalence, screening for hepatic fibrosis in the low-risk population is called for action in the primary care clinic. However, current guidelines provide conflicting recommendations on populations to be screened. We aimed to identify the target populations that would most benefit from screening for hepatic fibrosis in clinical practice. This study examined 1288 subjects who underwent magnetic resonance elastography. The diagnostic performance of the Fibrosis-4 (FIB-4) index and NAFLD fibrosis score was compared in the following groups: (1) ultrasonography (USG)-diagnosed NAFLD, (2) elevated liver enzyme, (3) metabolic syndrome, (4) impaired fasting glucose, and (5) type 2 diabetes regardless of fatty liver. Decision curve analysis was performed to express the net benefit of groups over a range of probability thresholds (Pts). The diabetes group showed a better area under the receiver operating characteristic curve (AUROC: 0.69) compared with subjects in the USG-diagnosed NAFLD (AUROC: 0.57) and elevated liver enzyme (AUROC: 0.55) groups based on the FIB-4 index. In decision curve analysis, the diabetes group showed the highest net benefit for the detection of significant fibrosis across a wide range of Pts. Patients with diabetes, even in the absence of fatty liver, would be preferable for hepatic fibrosis screening in low-risk populations.