Fat-suppressed T2-weighted Magnetic Resonance Imaging Research Articles

Qualitative and Quantitative Measures in the Infrapatellar Fat Pad in Older Adults: Associations with Knee Pain, Radiographic Osteoarthritis, Kinematics, and Kinetics of the Knee

ObjectiveThe purpose of this study is to delineate cross-sectional associations between qualitative and quantitative measures of the infrapatellar fat pad (IPFP) and knee symptoms, structure, kinematics, and kinetics in older adults. MethodsNinety eligible subjects (90 knees, mean age 54.0 years, 68.9% female) were examined at our centre. We used T2-weighted fat-suppressed magnetic resonance imaging (MRI) to evaluate signal intensity alteration, maximum sagittal area, and depth of the IPFP. Symptomatic osteoarthritis (SOA) was a pain subscale score greater than 0 on the Western Ontario McMaster Osteoarthritis Index. A Kellgren-Lawrence grade ≥ 2 identified incident radiographic osteoarthritis (iROA). Three-dimensional gait data were employed to analyze knee joint kinematics and kinetics. Correlation and regression analyses assessed associations between IPFP measurements and SOA, iROA, kinematics, and kinetics. ResultsThere were strong and positive associations between IPFP signal intensity alteration and both SOA and iROA in multivariable regression analyses [OR (95% CI): 2.849 (1.440 to 5.636), 2.356 (1.236 to 4.492), respectively]. Conversely, a significant negative correlation was observed between IPFP maximum area and flexion angle [B (95%CI): -1.557 (-2.549 to -0.564)]. Moreover, adjusting for covariates did not reveal any significant correlation between IPFP parameters and other indicators (P > 0.05, respectively). ConclusionIPFP signal intensity alteration and area were associated with knee clinical symptoms, structural abnormalities, and flexion angle in adults over 40, respectively. These findings suggest that IPFP may be a crucial imaging biomarker in early and middle knee osteoarthritis.

Differentiation of parotid pleomorphic adenoma from Warthin tumor using signal intensity ratios on fat-suppressed T2-weighted magnetic resonance imaging

ObjectiveTo investigate the value of magnetic resonance imaging (MRI) signal intensity ratios (SIRs) based on fat-suppressed T2-weighted imaging (FS-T2WI), together with demographic features, MRI anatomical characteristics, and SIRs of histopathological patterns of the tumors, in the differentiation of parotid pleomorphic adenoma (PA) from Warthin tumor (WT). Study DesignIn total, 90 patients with PA and 56 patients with WT were enrolled in the study. SIRs of tumor to normal parotid gland (SIR-T/P), spinal cord (SIR-T/S), and muscle (SIR-T/M) were calculated. Demographic and MRI anatomical features of the two patient groups were compared with univariate analysis and multivariate logistic regression analysis. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were analyzed to evaluate the utility of SIRs in distinguishing between PA and WT. ResultsSIR-T/P exhibited outstanding discriminating ability (AUC=0.934), SIR-T/S had excellent discrimination (AUC=0.839), and SIR-T/M showed acceptable discrimination (AUC=0.728). When SIR-T/P of 1.96 was selected as the cutoff value, sensitivity and specificity were 0.756 and 0.982, respectively. SIR-T/P, age, sex, and number of lesions were identified as independent predictors by multivariate logistic regression analysis. Differences in SIRs between histopathological patterns were significant. ConclusionSIR-T/P based on FS-T2WI is an effective discriminator in the differential diagnosis between PA and WT. Age, sex, and number of lesions provided additional value in the differentiation.

Greater medial proximal tibial slope is associated with bone marrow lesions in middle-aged women with early knee osteoarthritis.

Bone marrow lesion (BML) is an important magnetic resonance finding (MRI) finding that predicts knee osteoarthritis. The purpose of this study was to investigate the influence of proximal tibial morphology on BML, including the spreading root sign (SRS), in women without radiographic knee osteoarthritis (OA). It was hypothesized that varus alignment and a greater posterior tibial slopes (PTS) are associated with BML. A total of 359 female volunteers without knee OA who were participants in the Iwaki Health Promotion Project in 2017 or 2019 were enrolled. Participants were divided into the non-OA and early knee OA (EKOA) groups based on the Luyten's classification criteria. The presence of pathological cartilage lesions, BMLs, attritions, meniscal lesions and effusions was scored on T2-weighted fat-suppressed magnetic resonance imaging (MRI) according to the Whole-Organ MRI Scoring system. The medial proximal tibial angle (MPTA) and medial and lateral PTS (MPTS and LPTS, respectively) were measured. Regression and receiver operating characteristic (ROC) analyses were performed to reveal the relationship between BMLs and proximal tibial morphological parameters. Of the 359 participants, 54 (15%) were classified as having EKOA. The prevalence of cartilage lesions, BMLs, attritions, meniscal lesions and effusions was higher in the EKOA group than in the non-OA group. The two groups had no significant difference in the proximal tibial parameters. Regression analysis revealed that age and a smaller MPTA were associated with BML in both groups. Attrition (p = 0.029) and the MPTS (p = 0.025) were positively associated with BML in the EKOA group. The prevalence of BMLs was higher in women with EKOA and correlated with the varus and greater posterior slopes in those without radiographic knee OA. Level III, retrospective case-control study.

Interobserver Agreement in Automatic Segmentation Annotation of Prostate Magnetic Resonance Imaging.

We aimed to compare the performance and interobserver agreement of radiologists manually segmenting images or those assisted by automatic segmentation. We further aimed to reduce interobserver variability and improve the consistency of radiomics features. This retrospective study included 327 patients diagnosed with prostate cancer from September 2016 to June 2018; images from 228 patients were used for automatic segmentation construction, and images from the remaining 99 were used for testing. First, four radiologists with varying experience levels retrospectively segmented 99 axial prostate images manually using T2-weighted fat-suppressed magnetic resonance imaging. Automatic segmentation was performed after 2 weeks. The Pyradiomics software package v3.1.0 was used to extract the texture features. The Dice coefficient and intraclass correlation coefficient (ICC) were used to evaluate segmentation performance and the interobserver consistency of prostate radiomics. The Wilcoxon rank sum test was used to compare the paired samples, with the significance level set at p < 0.05. The Dice coefficient was used to accurately measure the spatial overlap of manually delineated images. In all the 99 prostate segmentation result columns, the manual and automatic segmentation results of the senior group were significantly better than those of the junior group (p < 0.05). Automatic segmentation was more consistent than manual segmentation (p < 0.05), and the average ICC reached >0.85. The automatic segmentation annotation performance of junior radiologists was similar to that of senior radiologists performing manual segmentation. The ICC of radiomics features increased to excellent consistency (0.925 [0.888~0.950]). Automatic segmentation annotation provided better results than manual segmentation by radiologists. Our findings indicate that automatic segmentation annotation helps reduce variability in the perception and interpretation between radiologists with different experience levels and ensures the stability of radiomics features.

Biochemical Markers of Aging (Advanced Glycation End Products) and Degeneration Are Increased in Type 3 Rotator Cuff Tendon Stumps With Increased Signal Intensity Changes on MRI

Background: Advanced glycation end products (AGEs) are end products of protein glycation that bind to the receptor for AGEs (RAGE) and activate nicotinamide adenine dinucleotide phosphate oxidase (NOX), resulting in increased oxidative stress and rotator cuff fragility. Stump classification using the signal intensity ratio of the tendon rupture site to the deltoid muscle in the coronal view of T2-weighted fat-suppressed magnetic resonance imaging (MRI) scans is an indicator of clinical outcomes after rotator cuff repair surgery. Comparing the signal intensities of the deltoid (D) and rotator cuff tears (C), Ishitani et al. classified C/D <0.8 as type 1, 0.8 to 1.3 as type 2, and >1.3 as type 3. Hypothesis/Purpose: It was hypothesized that the oxidative stress and collagen degeneration that occur in the rotator cuff due to accumulation of AGEs can be assessed on MRI scans (stump classification). Therefore, this study aimed to compare AGE-related factors in the rotator cuff tear site tissues based on stump classification. Study Design: Descriptive laboratory study. Methods: The authors included 30 patients (11 with type 1, 9 with type 2, and 10 with type 3; mean age, 62.3 years) who underwent surgery for complete rotator cuff tears at our hospital. Tendon tissue was harvested from the torn rotator cuff site during surgery for tissue and cell evaluation. Results: There was no significant difference in the mean age according to stump classification. The number of patients with diabetes was significantly larger in type 3 than in the other types (P < .05). Tissue evaluation showed significantly higher expression of AGE and RAGE staining in type 3 than in the other types (~6.7-fold; P < .01). Cell evaluation showed that the expression rates of reactive oxygen species and apoptosis were significantly higher in type 3 than in the other types (~4.3-fold; P < .01). Gene expression by real-time polymerase chain reaction showed significantly higher RAGE (~5.1-fold), NOX (~5.3-fold), and IL (~3.0-fold) in type 3 than in the other types (P < .05). Conclusion: Stump classification type 3 exhibited the highest accumulation of AGEs and the highest oxidative stress and apoptosis, suggesting a high degree of degeneration and inflammation. Imaging based on stump classification reflects the degeneration and fragility of the torn rotator cuff site. Clinical Relevance: This study provides evidence of a relationship between stump classification, which reflects rotator cuff fragility on MRI, and pathologies related to advanced glycation end products.

Comparison of new and old all-inside suture devices in meniscal cyst formation rates after meniscal repair.

We compared the magnetic resonance imaging (MRI)-confirmed cyst formation rate after meniscal tear repair using a new all-inside suture device (N group) versus the older all-inside suture device (O group). Between October 2008 and July 2017, 94 consecutive menisci of 89 patients were diagnosed with meniscal tears and underwent arthroscopic meniscal repair using the all-inside suture device. Five of these patients were lost to follow-up within 12months and were excluded from the study. The remaining 89 menisci were followed up for at least 12months and were included in this retrospective cohort study. Older all-inside suture devices (FasT-Fix, Ultra FasT-Fix) were used until December 2012, while the new all-inside suture device (FasT-Fix 360) was used from January 2013 onwards. Meniscal cysts were detected on T2-weighted fat-suppressed MRI at 12months postoperatively. Multiple logistic regression analysis was used to identify demographic and clinical factors associated with the use of the new all-inside suture device and cyst formation. In total, 36 and 53 menisci were included in the N and O groups, respectively. The incidence of meniscal cysts was significantly greater in the O group (14 out of 53, 26.4%) than in the N group (two out of 36, 5.56%) (P = 0.012). Two patients in the O group had symptomatic cysts that required removal. Multivariate logistic analyses showed that the cyst formation risk significantly decreased after using the new all-inside suture device than the older all-inside suture devices (odds ratio = 0.139; P = 0.04). The MRI-confirmed cyst formation rate after meniscal tear repair was significantly lower using the new than the older all-inside suture devices, indicating that the use of a low-profile device may decrease the cyst formation rate.

Spinal Cerebrospinal Fluid Leak: Current Concepts and Management Policies

In this article we provide an update on the recent developments in understanding the diagnosis and treatment of spinal cerebrospinal fluid(CSF)leaks. Patients with spinal CSF leak show an increasingly broad spectrum of clinical presentations including intractable whiplash-associated disorder(WAD)and orthostatic dysregulation in childhood, in addition to classical spontaneous intracranial hypotension(SIH). A simple understanding of the condition defined by the presence of low CSF pressure is no longer sufficient or accurate. Fat-suppressed T2-weighted magnetic resonance images and continuous epidural fluid infusion as a diagnostic therapy ensure accurate diagnosis. Accurate localization of the leak followed by targeted epidural blood patch(EBP)significantly improves the outcome of patients with spinal CSF leak. In addition to the known sites of CSF leakage, a newly identified CSF leak site, at the craniovertebral junction dural entry point of the vertebral artery(VA), is described.

Texture Analysis of Fat-Suppressed T2-Weighted Magnetic Resonance Imaging and Use of Machine Learning to Discriminate Nasal and Paranasal Sinus Small Round Malignant Cell Tumors.

ObjectiveWe used texture analysis and machine learning (ML) to classify small round cell malignant tumors (SRCMTs) and Non-SRCMTs of nasal and paranasal sinus on fat-suppressed T2 weighted imaging (Fs-T2WI).MaterialsPreoperative MRI scans of 164 patients from 1 January 2018 to 1 January 2021 diagnosed with SRCMTs and Non-SRCMTs were included in this study. A total of 271 features were extracted from each regions of interest. Datasets were randomly divided into two sets, including a training set (∼70%) and a test set (∼30%). The Pearson correlation coefficient (PCC) and principal component analysis (PCA) methods were performed to reduce dimensions, and the Analysis of Variance (ANOVA), Kruskal-Wallis (KW), and Recursive Feature Elimination (RFE) and Relief were performed for feature selections. Classifications were performed using 10 ML classifiers. Results were evaluated using a leave one out cross-validation analysis.ResultsWe compared the AUC of all pipelines on the validation dataset with FeAture Explorer (FAE) software. The pipeline using a PCC dimension reduction, relief feature selection, and gaussian process (GP) classifier yielded the highest area under the curve (AUC) using 15 features. When the “one-standard error” rule was used, FAE also produced a simpler model with 13 features, including S(5,-5)SumAverg, S(3,0)InvDfMom, Skewness, WavEnHL_s-3, Horzl_GlevNonU, Horzl_RLNonUni, 135dr_GlevNonU, WavEnLL_s-3, Teta4, Teta2, S(5,5)DifVarnc, Perc.01%, and WavEnLH_s-2. The AUCs of the training/validation/test datasets were 1.000/0.965/0.979, and the accuracies, sensitivities, and specificities were 0.890, 0.880, and 0.920, respectively. The best algorithm was GP whose AUCs of the training/validation/test datasets by the two-dimensional reduction methods and four feature selection methods were greater than approximately 0.800. Especially, the AUCs of different datasets were greater than approximately 0.900 using the PCC, RFE/Relief, and GP algorithms.ConclusionsWe demonstrated the feasibility of combining artificial intelligence and the radiomics from Fs-T2WI to differentially diagnose SRCMTs and Non-SRCMTs. This non-invasive approach could be very promising in clinical oncology.

Abstract 10227: High-Sensitive Magnetic Particle Imaging of Intraplaque Hemorrhage for Identification of Unstable Atherosclerotic Plaques

Introduction: Intraplaque hemorrhage (IPH), which is believed to arise from immature neovessels, drives atherosclerosis progression and is an imaging predictor of stroke and myocardial infarction. However, detection of IPH using magnetic resonance imaging (MRI) might be limited due to false signals from varied plaque components. Magnetic particle imaging (MPI) is a novel tomographic method that directly images the magnetization of ferromagnetic particles. Aims: To test whether MPI can image IPH for detecting unstable plaques and exploring the mechanism of IPH. Methods: The tandem stenosis (TS) mouse model was used to establish unstable plaques with IPH. The intervention agent used for reducing IPH was 4-ABAH. TS ApoE -/- mice and human carotid endarterectomy samples were scanned with MPI and computed tomography. IPH was confirmed by fat-suppressed T1-weighted MRI and Prussian blue staining. Plaque specimens were analyzed histologically. Results: Human carotid samples exhibited endogenous MPI signals, which were related to IPH. Hemosiderin was likely the source of MPI signals. Seven weeks post-TS, unstable plaques in the right carotid artery showed endogenous MPI signals, which were three-fold greater compared with stable plaques in the brachiocephalic artery or normal arterial wall (P &lt; 0.05). From the temporal points, MPI signals in unstable plaques increased from 3.05 ± 1.45 (4 weeks) to 7.29 ± 4.47 (7 weeks) and reduced to 2.59 ± 0.84 (11 weeks) (P &lt; 0.05), while intraplaque neovessel densities showed no difference. Compared with 4 or 7 weeks post-TS, intraplaque neovessels at 11 weeks revealed a more mature phenotype indicated by increased neovessel lumen areas and VE-cadherin (endothelial junction marker) expressions (P &lt; 0.05). Administered 4-ABAH attenuated MPI signals in unstable plaques (9.38 ± 6.75 vs. 3.11 ± 1.25, P &lt; 0.05) and downregulated vWF (endothelial damage marker) expressions (P &lt; 0.05) without affecting neovessel densities or lumen areas. Conclusions: MPI allows ex vivo IPH imaging in human carotid tissues, in vivo IPH monitoring and unstable plaque detection in ApoE -/- mice. MPI-detected IPH is likely associated with endothelial barrier function. As a result, MPI is a promising method for detecting unstable plaques in patients.

Relationship between abnormalities detected by magnetic resonance imaging and knee symptoms in early knee osteoarthritis

We investigated the prevalence of magnetic resonance imaging (MRI) findings and their relationship with knee symptoms in women without radiographic evidence of knee osteoarthritis (KOA). This cross-sectional cohort study included 359 Japanese women without radiographic evidence of KOA (Kellgren‒Lawrence grade < 2). All participants underwent T2-weighted fat-suppressed MRI of their knees. Structural abnormalities (cartilage damage, bone marrow lesions [BMLs], subchondral cysts, bone attrition, osteophytes, meniscal lesions, and synovitis) were scored according to the whole-organ MRI score method. Knee symptoms were evaluated using the Knee Injury and Osteoarthritis Outcome Score. Participants were divided into early and non-KOA groups based on early KOA classification criteria. Logistic regression analysis was performed to evaluate the relationship between MRI abnormalities and knee symptoms. Cartilage damage was the most common abnormality (43.5%). The prevalences of cartilage damage, BMLs, subchondral cysts, bone attrition, meniscal lesions, and synovitis were higher in patients with early KOA than in those without. Synovitis (odds ratio [OR] 2.254, P = 0.002) and meniscal lesions (OR 1.479, P = 0.031) were positively associated with the presence of early KOA. Synovitis was most strongly associated with knee pain and might be a therapeutic target in patients with early KOA.

Microsurgical Anatomy of the Inferior Petroclival Vein and its Relation to Surrounding Structures: A Cadaveric and Radiological Study.

The inferior petroclival vein (IPV) courses along the extracranial surface of the petroclival fissure. It is occasionally involved in vascular diseases and has recently been used for vascular access to the cavernous sinus. However, detailed descriptions of its anatomy are currently lacking. To define the anatomic relationship between the IPV and its surrounding structures based on cadaveric dissection and radiological analysis. A dry skull and an injected cadaver head were examined to reveal the relationships between the IPV and its surrounding structures. The existence of the IPV and its relationships with other venous structures were also examined by contrast-enhanced, fat-suppressed T1-weighted magnetic resonance imaging in 26 patients (51 sides). The entire course of the IPV was shown via stepwise cadaver dissection from below. Its relationships with surrounding structures, such as the jugular bulb, sigmoid sinus, inferior petrosal sinus, petrosal venous confluence, and the posterior, lateral, and anterior condylar veins, were also shown. In the radiological analysis, the IPV was identified on all sides. The rostral end of the vein was connected to the venous plexus around the carotid artery on all sides. The vein drained into the caudal end of the inferior petrosal sinus (49/51 sides, 96.1%) or into the anterior condylar vein (2/51 sides, 3.9%). A precise understanding of the anatomy of the IPV will enable endovascular and skull base surgeons to achieve diagnoses and gain safe access to lesions involving the IPV.

Development and Evaluation of Deep Learning-Accelerated Single-Breath-Hold Abdominal HASTE at 3 T Using Variable Refocusing Flip Angles.

Deep learning (DL) reconstruction enables substantial acceleration of image acquisition while maintaining diagnostic image quality. The aims of this study were to overcome the drawback of specific absorption rate (SAR)-related limitations at 3 T and to develop a DL-accelerated single-breath-hold half-Fourier acquisition single-shot turbo spin echo (HASTE) sequence for 2-dimesional T2-weighted fat-suppressed magnetic resonance imaging of the abdomen at 3 T using a variable flip angle (FA) evolution for the refocusing radiofrequency pulses, as well as to evaluate its feasibility and image quality in comparison to state-of-the-art T2-weighted fat-suppressed imaging technique (BLADE). First, a suitable FA evolution with low cardiac motion-related signal loss (CRSL) and low SAR was determined through a prospective volunteer study with 11 participants. Image quality and diagnostic confidence with 5 different FA evolutions of a HASTEDL were assessed to identify the most suitable FA evolution. Second, the identified FA evolution was implemented clinically and evaluated in 51 patients undergoing a clinically indicated liver magnetic resonance imaging at 3 T. Two radiologists assessed the HASTEDL and standard sequences regarding overall image quality, noise, contrast, sharpness, artifacts, CRSL, and diagnostic confidence using a Likert scale ranging from 1 to 4, with 4 being the best. Comparative analyses were conducted to assess the differences between HASTEDL (acquisition time, 21 seconds; single breath-hold) and the routinely used T2-weighted BLADE sequence (acquisition time, 4 minutes; respiratory triggering). From the volunteer study, the FA evolution characterized by the control points 130-90-110-130 degrees (HASTEDL) was identified as optimal among the 5 evolutions evaluated and was implemented in our clinical protocol. In all 51 patients, HASTEDL was successfully acquired at 3 T and showed excellent image quality (median, 4; interquartile range, 3-4). Although BLADE was rated significantly higher for overall image quality, noise, contrast, sharpness, artifacts, CRSL, and diagnostic confidence than HASTEDL, no differences were found concerning the number (n = 102) and measured diameter of the detected hepatic lesions between the 2 sequences BLADE and HASTEDL. The proposed single-breath-hold abdominal HASTEDL with variable refocusing FAs is feasible at 3 T within SAR limits and yields high image quality and diagnostic confidence as compared with a standard T2-weighted acquisition technique, at a 10th of the acquisition time.

Tibial plateau inclination is associated with bone marrow lesions in early knee osteoarthritis

Purpose: While varus inclination of proximal tibia and bone marrow lesion (BML) are important factor for understanding knee osteoarthritis (OA) etiology, the relationship between these wo factors remain unclear. This study aimed to investigate the effect of proximal tibial inclination and serum bone metabolic markers on bone marrow lesion (BML) in the Japanese general population with early knee osteoarthritis (EKOA). Methods: A total of 441 female volunteers who participated in the Iwaki Health Promotion Project in 2017 were enrolled. Participants without radiographic abnormalities were divided into normal and EKOA groups according to Luyten’s classification criteria for EKOA (Figure 1). In this study, proximal tibial inclination was assessed with reference to growth plate (GP). The GP-tibial plateau (TP) angle was defined as the angle between the GP and TP lines (a), whereas the GP-medial tibial plateau (MTP) angle was defined as the angle between the GP and MTP lines (b) The medial proximal tibial angle (MPTA), GP-TP angle, and GP-MTP angle were measured on standing anteroposterior radiographs of the knees. BML severity on T2-weighted fat-suppressed magnetic resonance imaging (MRI) was scored using the Whole-Organ MRI Score method. Serum levels of N-telopeptide of type I collagen (NTx), tartrate-resistant acid phosphatase-5b (TRACP-5b), bone-specific alkaline phosphatase, procollagen type I N-terminal propeptide, pentosidine, and homocysteine were assessed. Serum concentrations of bone metabolic markers and radiographic measurements were compared using the Wilcoxon rank sum test. To investigate the relationship among BML, proximal tibial inclination, and serum bone metabolic markers, multiple linear regression analyses were conducted with the total BML score as the dependent variable and with age, body mass index, MPTA, GP-MTP angle, GP-TP angle, and serum bone metabolic markers as independent variables in patients with and without EKOA. To estimate the predictive cut-off level of proximal tibial inclination for detecting BML, receiver operating characteristic (ROC) analysis was performed for the EKOA group. Finally, in order to evaluate the cut-off values, the participants were divided into three groups according to the cut-off values estimated from the ROC analysis—the neutral group, tibia vara (extra-articular deformity) group, and genu varum (intra-articular deformity) group. Serum bone metabolic marker levels were compared among these three groups using one-way analysis of variance and Tukey’s test. Of these 309 participants, 48 participants (16%) had EKOA. With reference to the GP line, the GP-TP angle was inclined at 3.6±1.1° and the GP-MTP angle was 9.9±2.6°.Tabled 1Clinical characteristics of the participantsGP not observedGP observedp valueTotalNon-OAEKOASample number13130926148nsAge (years)52.7±14.154.5±9.554.4±9.755.0±8.8nsHeight (cm)156.1±6.0157.4±6.0157.5±6.0156.8±6.1nsBMI (kg/m2)22.4±3.622.0±3.121.9±3.122.3±3.2nsMPTA (°)86.6±1.286.1±5.986.4±1.586.6±1.4nsGP-TP (°)3.6±1.13.6±1.23.6±0.9nsGP-MTP (°)9.9±2.69.9±2.69.8±2.6nsNTx (nM)15.0±5.114.9±3.815.0±3.814.5±3.7nsTRACP-5b (mU/dL)415±190422.4±185431±14393.5±27nsBAP (μg/L)13.8±5.013.0±8.913.1±4.99.8±4.3nsPINP (μg/L)51.0±19.647.4±18.447.8±1.545.9±2.6nsPentosidine (pmol/mL)27.4±9.630.5±24.329.3±16.837.1±47.2nsHomocysteine (nmol/mL)9.0±3.18.5±2.78.5±0.28.3±0.4ns Open table in a new tab Serum bone metabolic marker levels did not significantly differ between the non-OA and EKOA groups. The MPTA was negatively correlated with the GP-TP and GP-MTP angles (r=−0.253, p<0.001 and r=−0.369, p<0.001, respectively). The BML was detected in 64 participants (31%) out of 205 participants who were performed MRI (). The MPTA was smaller in participants with EKOA who had BML than in those who did not (p=0.020), and the GP-MTP angle was larger in participants with BML than in those without BML (p=0.018).Tabled 1Radiographic measurements between participants with and without BMLNon-OAp valueEKOAp valueBML (-)BML (+)BML (-)BML (+)MPTA86.4±1.486.3±1.8ns86.8±1.386.0±1.20.020GP-TP3.5±1.33.5±1.1ns3.5±1.03.9±0.7nsGP-MTP10.0±2.59.9±2.9ns9.4±2.711.1±2.00.018 Open table in a new tab Linear regression analysis revealed that age was positively associated with BML severity in overall participants. In the non-OA group, serum TRACP-5b level was positively associated with BML (β=0.236, p=0.047). Proximal tibial inclination (MPTA and GP-MTP angle) was associated with BML only in the EKOA group (β=−0.281, p=0.011 and β=0.262, p=0.046, respectively).Tabled 1Relationship among bone marrow lesion, tibial inclination, and serum bone metabolic markersParameterNon-OApEKOApββAge0.1340.0090.503<0.0001BMI−0.014ns−0.072nsMPTA−0.056ns−0.2890.011GP-MTP−0.053ns0.2620.046GP-TP0.082ns0.137nsTotal PINP0.052ns0.060nsTRACP-5b0.2360.0470.076nsBAP−0.004ns−0.039nsNTx−0.032ns−0.074nsPentosidine0.024ns−0.136nsHomocysteine−0.011ns−0.136ns Open table in a new tab The ROC analysis indicated that the cutoff values for detecting BML were 86.7° for the MPTA (AUC: 0.703, p=0.030) and 9.7° for the GP-MTP angle (AUC: 0.706, p=0.028). Based on these cutoff values, tibial bone morphology was divided into the following three groups: neutral (MPTA ≥86.7°). (a), tibia vara (extra-articular deformity: MPTA <86.7° and GP-MTP angle <9.7°) (b), and genu varum (intra-articular deformity: MPTA <86.7° and GP-MTP angle ≥9.7°) groups (c). In the neutral group, 55 (46%) participants out of 120 participants had GP-MTP angle ≥9.7°. The serum NTx level was significantly lower in the genu varum group than in the tibia vara group (p=0.023). The serum TRACP-5b level was significantly lower in the genu varum group than in the neutral group (p=0.012).Tabled 1Serum bone metabolic marker levels among proximal tibial inclination typesNeutral (MPTA ≥86.7°)Inclined (MPTA <86.7°)p valueTibia vara (MTP-GP <9.7°)Genu varum (MTP-GP ≥9.7°)Sample number12075114MPTA87.6±0.785.5±0.985.1±1.2<0.001GP-MTP9.1±2.47.7±1.512.2±1.7<0.001NTx14.9±3.515.9±7.913.8±3.90.023BAP13.1±0.412.5±0.511.7±0.4nsTRACP-5b421±193409±202351±1680.012PINP46.8±18.249.4±27.245.1±19.7nsPentosidine32.6±2.230.5±28.228.2±2.2nsHomocysteine8.4±2.58.6±3.08.3±2.5ns Open table in a new tab Conclusions: The GP was a reasonable reference for assessing TP inclination. The presence of BML was associated with greater TP inclination and higher bone formation activity, even in participants without radiographic abnormalities. Residual medial tibial inclination may potentially result in knee pain and symptoms in EKOA.

Bone marrow lesion severity was associated with proximal tibial inclination in early knee osteoarthritis.

This study aimed to investigate the effect of tibial plateau (TP) inclination and serum bone metabolic markers on bone marrow lesion (BML) in the general Japanese population with early knee osteoarthritis (EKOA). A total of 441 female volunteers who participated in the Iwaki Health Promotion Project in 2017 were enrolled. Participants without radiographic abnormalities were divided into normal and EKOA groups according to the Luyten's classification criteria for EKOA. The medial proximal tibial angle (MPTA), growth plate-TP angle, and growth plate-medial tibial plateau (MTP) angle were measured on standing anteroposterior radiographs of the knees. BML severity on T2-weighted fat-suppressed magnetic resonance imaging (MRI) was scored using the Whole-Organ MRI Score method. Serum levels of N-telopeptide of type I collagen, tartrate-resistant acid phosphatase-5b (TRACP-5b), bone-specific alkaline phosphatase, procollagen type I N-terminal propeptide, pentosidine, and homocysteine were assessed. Linear regression analysis was conducted to investigate the relationship between proximal tibial inclination, BML, and serum bone metabolic markers. The growth plate was observed in 309 (70%) participants, and 48 (16%) participants had EKOA. The mean MPTA, growth plate-TP angle, and growth plate-MTP angle were 86.1 ± 5.9°, 3.6 ± 1.1°, and 9.9 ± 2.6°, respectively. The MPTA was negatively correlated with the growth plate-TP and growth plate-MTP angles (p = 0.006, p < 0.001). Participants with EKOA who had BML exhibited greater growth plate-MTP angle than those who did not (p = 0.018). Regression analysis revealed that BML severity was positively associated with MPTA (p = 0.036) and a bone formation marker (p = 0.045). BML severity was positively associated with proximal tibial inclination and serum TRACP-5b level in participants with EKOA and normal knees, respectively. Assessment of proximal tibial inclination may provide insight into potential BML risk. Residual medial tibial inclination may potentially result in knee pain and symptoms in EKOA. III.

Quantification of Lumbar Spinal Canal Stenosis by Quantitative Fat-Suppressed Contrast-Enhanced Magnetic Resonance Imaging.

Fat-suppressed T1-weighted magnetic resonance images (MRIs) enhanced with gadolinium can evaluate the internal vertebral venous plexus and cauda equina. This study compared such findings with clinical situations and discusses whether these are helpful for symptomatic grading and selection at the surgical level in patients with lumbar central stenosis. A total of 263 patients (337 levels < 75 mm2 of dural cross sectional area (DCSA)) were included. The enhancement patterns of dorsal epidural vein (DVCE), periradicular vein (PVCE) and intraradicular vein (IRCE) were assessed qualitatively. The quantification of IRCE was acquired by the ratio (%) (enhancement parameters: MS/P1, MS/P2, WR/P1, WR/P2) of signal intensities between the cauda equina (MS-IRCE: maximal spot rootlet, WR-IRCE: whole rootlets) and psoas muscle (P1, P2). Receiver-operator characteristic curves were plotted to obtain imaginary cutoff values for the prediction of symptomatic appearance or operation decision. All levels were classified into seven groups on the basis of pain distribution and the presence of IRCE. PVCE was significantly related to high incidences of symptoms, unilaterality and operation. DVCE and IRCE were connected with high incidences of symptoms, bilaterality and operation. IRCE was also related to high visual analogue scale (VAS), small DCSA and high enhancement parameters. The order of the group was concordant with the degree of enhancement parameters (p = 0.000). Cutoff values of enhancement parameters for prediction were as follows: symptoms (147/123/140/121), bilaterality (165/139/157/137) and operation (164/139/159/138). Enhancement patterns and parameters could help in stratification, grading and decision-making at the surgical level.

Radiological imaging features of the salivary glands in xerostomia induced by an immune checkpoint inhibitor

The clinical features of xerostomia induced by immune checkpoint inhibitors (ICI) are similar to those of Sjögren’s syndrome (SS), whereas the immunohistological and serological features are known to differ from those of SS. However, the radiologic imaging features of salivary glands are not yet well known. We report a case of a 56-year-old male patient diagnosed with ICI-induced xerostomia. The patient underwent various imaging examinations to investigate the condition of the salivary glands, which indicated the following: (1) less specific findings on contrast-enhanced computed tomography, (2) mixed with intermediate and low signal intensity on both T1-weighted and fat-suppressed T2-weighted magnetic resonance imaging and poor “salt and pepper” appearance on magnetic resonance sialography, and (3) multiple ovoid hypoechoic areas with hyperechoic bands without acute sialadenitis on ultrasound. These radiologic imaging findings suggested remarkable lymphocyte infiltration, which could be a characteristic of ICI-induced xerostomia.

Comparison of CT and MRI images for the prediction of soft-tissue sarcoma grading and lung metastasis via a convolutional neural networks model

To realise the automated prediction of soft-tissue sarcoma (STS) grading and lung metastasis based on computed tomography (CT), T1-weighted (T1W) magnetic resonance imaging (MRI), and fat-suppressed T2-weighted MRI (FST2W) via the convolutional neural networks (CNN) model. MRI and CT images of 51 patients diagnosed with STS were analysed retrospectively. The patients could be divided into three groups based on disease grading: high-grade group (n=28), intermediate-grade group (n=15), low-grade group (n=8). Among these patients, 32 had lung metastasis, while the remaining 19 had no lung metastasis. The data were divided into the training, validation, and testing groups according to the ratio of 5:2:3. The receiver operating characteristic (ROC) curves and accuracy values were acquired using the testing dataset to evaluate the performance of the CNN model. For STS grading, the accuracy of the T1W, FST2W, CT, and the fusion of T1W and FST2W testing data were 0.86, 0.89, 0.86, and 0.85, respectively. In addition, Area Under Curve (AUC) were 0.96, 0.97, 0.97, and 0.94 respectively. For the prediction of lung metastasis, the accuracy of the T1W, FST2W, CT, and the fusion of T1W and FST2W test data were 0.92, 0.93, 0.88, and 0.91, respectively. The corresponding AUC values were 0.97, 0.96, 0.95, and 0.95, respectively. FST2W MRI performed best for predicting STS grading and lung metastasis. MRI and CT images combined with the CNN model can be useful for making predictions regarding STS grading and lung metastasis, thus providing help for patient diagnosis and treatment.

Tendon stump type on magnetic resonance imaging is a predictive factor for retear after arthroscopic rotator cuff repair

Fatty infiltration of the rotator cuff musculature increases in larger tearsand is a factor in retearing. However, tearing may recur even in patients with small original tears and little fatty infiltration of the rotator cuff musculature. We devised a system to classify the rotator cuff tendon stump by magnetic resonance imaging (MRI) signal intensityand investigated prognosis-related factors associated with retear based on other MRI findings. We analyzed and compared the signal intensity of the rotator cuff tendon stump and deltoid on preoperative T2-weighted fat-suppressed MRI in 305 patients who underwent primary arthroscopic rotator cuff repair. We also investigated the tear size, Goutallier stage, and global fatty degeneration index. In a type 1 stump, the tendon stump had a lower (darker) signal intensity than the deltoid. In type 2, the signal intensities of the tendon stump and deltoid were equivalent. In type 3, the signal intensity of the tendon stump was higher (whiter) than that of the deltoid. Multiple regression analysis of the association between retear and other parameters identified stump type (odds ratio [OR], 4.28), global fatty degeneration index (OR, 2.99), and anteroposterior tear size (OR, 1.06) as significant factors. The retear rates were 3.4% for type 1 stumps, 4.9% for type 2, and 17.7% for type3. Type 3 stumps had a significantly higher retear rate, suggesting that stump signal intensity may be an important indicator for assessing the stump's condition. Our stump classification may be useful in choosing suture techniques and postoperative therapies.

Symptomatic bone marrow lesions induced by reduced bone mineral density in middle-aged women: a cross-sectional Japanese population study

BackgroundThe etiology of bone marrow lesions (BMLs) without knee osteoarthritis (KOA) and their association with bone fragility are unclear. We aimed to investigate the association between BMLs, bone mineral density (BMD), and bone markers in women without radiographic evidence of KOA.MethodsThis single-center cross-sectional study in a Japanese population included 266 women without radiographic evidence of KOA, which was defined as a Kellgren-Lawrence grade < 2. All participants underwent coronal and sagittal T2-weighted fat-suppressed magnetic resonance imaging of their right knee. BML severity was scored according to the Whole-Organ MRI Scoring method. BMD was measured by dual-energy X-ray absorptiometry of the forearm. Levels of bone markers (bone-alkaline phosphatase [BAP], type I procollagen N-terminal propeptide [PINP], cross-linked N-telopeptide of type I collagen [NTx], and tartrate-resistant acid phosphatase-5b [TRACP-5b]), pentosidine, and homocysteine were assessed in the serum. Knee symptoms were evaluated on the basis of the Knee injury and Osteoarthritis and Outcome Score (KOOS). Participants were divided into symptomatic knee and asymptomatic knee groups on the basis of their KOOS according to the classification criteria for early KOA. Multiple linear regression analysis was performed to evaluate the relationship between BMLs, BMD, and bone markers.ResultsThe prevalence of BML was 35.3%. Age and some bone marker levels (BAP, PINP, NTx, and TRACP-5b) were higher, and all KOOS subscale scores and BMD were lower in participants with BMLs than in those without BMLs. On multiple linear regression analysis, BMD was negatively associated with BMLs (p = 0.014) in participants with symptomatic knees. There was no such association in participants with asymptomatic knees (p = 0.918). Among the bone markers, BAP (p = 0.006) and PINP (p = 0.043) were positively associated with BMLs in participants with symptomatic knees, while BAP (p = 0.038) and TRACP-5b (p = 0.011) were positively associated with BMLs in participants with asymptomatic knees.ConclusionsIn symptomatic Japanese women without radiographic evidence of KOA, BMD is negatively associated and some bone markers are positively associated with BMLs after adjustment for age and BMI. Thus, maintaining systemic bone metabolism could contribute to BML prevention in patients with pre-radiographic KOA.

Orbital Interstitial Fluid: Evidence of a Potential Pathway for Extracranial Cerebrospinal Fluid Absorption.

The aim of the study was to describe the prevalence and characteristics of orbital interstitial fluid seen on magnetic resonance (MR) images of infants and young children. Fat-suppressed axial T2-weighted MR images of 100 consecutive infants and young children (<6 years) without orbital pathology were retrospectively reviewed by 2 neuroradiologists. The presence, location, and extent of high-signal orbital interstitial fluid were characterized and tabulated as a function of age. Orbital interstitial fluid was detected in 90 (90%) of the 100 subjects overall, present in 100% (75/75) of infants and children younger than 3 years, 75% (12/16) of those aged 3 to 5 years, and 33% (3/9) of those aged 5 to 6 years. The fluid was bilateral and symmetric in all cases. Two morphologic patterns were distinguished, which often co-existed: (1) a focal discrete curvilinear band of fluid in the posterior-lateral orbit, more common in younger patients, and (2) an ill-defined, lace-like pattern primarily in the superior orbit seen in subjects of all ages. Orbital interstitial fluid as detected by fat-suppressed T2-weighted MR imaging is a nearly universal finding in infants and young children and should not be considered pathologic. It may have either a focal or lace-like pattern or both. Orbital interstitial fluid decreases in size and prevalence as a function of age but is still present in nearly half of children aged 4 to 6 years. Possible explanations concerning the nature and origin of this fluid are presented, including the fascinating possibility that the fluid represents an extracranial pathway for outflow of cerebrospinal fluid.