Detection Of Bone Marrow Edema Research Articles

Bone marrow edema in non-traumatic hip: high accuracy of dual-energy CT with water-hydroxyapatite decomposition imaging.

To evaluate the diagnostic performance of dual-energy CT with water-hydroxyapatite (HAP) imaging for bone marrow edema in patients with non-traumatic hip pain. Forty patients (mean age, 58 years; 16 male and 24 female) who underwent rapid kVp-switching dual-energy CT and MRI within 1 month between April 2018 and February 2019 with hip pain but no trauma were enrolled. Two radiologists retrospectively evaluated 80 hip joints for the presence, extent (femoral head involved, head and neck, and head to intertrochanter), and severity (mild edema, moderate, severe) of bone marrow edema on dual-energy water-HAP images. Water mass density (mg/cm3) on water-HAP images was determined with region of interest-based quantitative analysis. MRI served as the standard of reference. Sensitivity, specificity, and accuracy of readers 1 and 2 for the identification of bone marrow edema in water-HAP images were 85% and 85%, 93% and 73%, and 89% and 79%, respectively. The area under the receiver operating characteristic curve was 0.96 for reader 1 and 0.91 for reader 2 for differentiation of the presence of edema from no edema. The optimal water mass density to classify the presence of edema for reader 1 was 951 mg/cm3 with 93% sensitivity and 93% specificity and for reader 2 was 957 mg/cm3 with 80% sensitivity and 80% specificity. The more severe the edema, the higher was the mean water density value (p < 0.035). Dual-energy water-HAP images showed good diagnostic performance for bone marrow edema in patients with non-traumatic hip pain. • Dual-energy water-HAP imaging depicts bone marrow edema in patients with non-traumatic hip pain and may serve as an alternative to MRI in select patients. • A cutoff value of 951 mg/cm3mean water mass density results in 93% sensitivity and 93% specificity for the detection of bone marrow edema. • The more severe the bone marrow edema, the higher the mean water density value.

Top-Ten Tips for Dual-Energy CT in MSK Radiology.

Dual-energy computed tomography (DECT) has the potential to detect musculoskeletal pathology with greater sensitivity than conventional CT alone at no additional radiation dose to the patient. It therefore has the potential to reduce the need for further diagnostic imaging or procedures (e.g., joint aspirations in the case of gout or magnetic resonance imaging to confirm undisplaced fractures).DECT is a well-established technique for the detection of gout arthropathy. Multiple newer applications have shown clinical potential including bone marrow edema detection and metal artifact reduction. Collagen analysis, bone marrow lesion detection, and iodine mapping in CT arthrography are areas of possible future application and development.This article outlines 10 tips on the use of DECT imaging of the musculoskeletal system, explaining the technique and indications with practical suggestions to help guide the radiologist.

Performance of magnetic resonance imaging in the diagnosis of axial spondyloarthritis: a systematic literature review.

To summarize the evidence on the performance of MRI for the diagnosis of axial SpA. This was a systematic literature review of all studies from January 2013 to March 2017 including adult patients with clinically suspected axial SpA undergoing MRI. Studies from a previously published systematic literature review up to January 2013 were also included. Thirty-one studies were included. Six studies demonstrated good sensitivity and specificity for SI joint (SIJ) bone marrow oedema (BMO). Specificity was increased by the presence of other structural lesions alongside BMO, particularly erosions or fat infiltration. Four studies addressed the utility of SIJ fat infiltration, finding good sensitivity but poor specificity. SIJ erosions showed good specificity in five studies. Studies addressing high T1 signal in the SIJ, fluid signal in the SIJ, ankylosis, sclerosis, capsulitis, backfill and vacuum phenomenon reported limited diagnostic value. In the spine, four studies reported moderate sensitivity and specificity for corner inflammatory lesions, and four reported poor sensitivity and specificity for spinal fat infiltration. Five studies evaluated the added value of spinal MRI over SIJ MRI alone, with variable results depending on the cohort. Six studies addressed the effect of acquisition parameters on diagnostic accuracy: fat-saturated T2-weighted imaging and short tau inversion recovery (STIR) imaging showed comparable utility in identifying BMO. Three studies showed that gadolinium was of minimal added value in the detection of BMO. These results confirmed the diagnostic utility of MRI in axial SpA. Performance varied according to the characteristics of the cohort and the number and combination of MRI lesions considered.

Detection of bone marrow edema in the head and neck with dect – ready to use?

Detection of bone marrow edema in the head and neck with dect – ready to use?

Detecting hip osteoarthritic degenerative changes in MRI using deep learning

Purpose: Osteoarthritis (OA) is a debilitating joint disease that involves the degeneration of the articular cartilage and affects more than 25% of the adult population. Previously, SHOMRI (Scoring Hip Osteoarthritis with MRI) has been proposed as an MR-based hip OA evaluation system, based on the presence of morphological abnormalities, such as bone marrow edema, cartilage lesions, labral abnormalities and cysts. However, manual identification of bone and cartilage abnormalities in MR images can be laborious and time consuming. Thus, the goal of this study was to develop a fully automated deep learning pipeline to identify morphological and degenerative changes in patients with OA of the hip joint that would act as a radiology assist in image interpretation. Methods: 133 subjects with radiographic or symptomatic hip OA (as graded by SHOMRI) were recruited for this study (age 42.88±12.75 years, BMI 22.94± 3.029 kg/m3, 75 males, 58 females). T2-weighted, fat-saturated coronal hip images (TR = 60 ms, TR = 2.4s, slice thickness=4 mm, matrix=288x224, FOV=14-20 cm) were acquired on a 3T Discovery 750 MR scanner (GE Healthcare, Waukesha, WI). An end-to-end automated pipeline was built to evaluate morphological degenerative changes (Fig. 1). It included an object detection deep convolutional neural network (DCNN) that generated cropped images of the hip joint and a classification DCNN that identified the presence of morphological bone and cartilage abnormalities. The object detection network was implemented in Python and TensorFlow Object Detection API (Google, Mountain View, CA) on single-shot detector with Resnet-50 feature pyramid network (RetinaNet) architecture. The model was pre-trained on ImageNet classification and COCO object detection datasets and trained with Nvidia Titan X GPU on a dataset of 70 hip MR images with bounding boxes around the femoral head (90% train / 10% validation, random flip augmentation, batch=8, 25000 iterations). The network’s output was the central slice and the bounding box over the femoral head, which was used to extract a set of 5 slices, cropped around the weight bearing region of the joint (Fig. 1). These cropped images were labeled by two trained radiologists on the presence of bone marrow edema and cartilage lesions. The classification DCNN was implemented using PyTorch framework with DenseNet-100 architecture, pretrained on grayscale CIFAR-32 dataset. The model used an SGD optimizer with initial learning rate of 0.005 reduced to 0.001 after 20 epochs, momentum=0.9, weight_decay=5e-4, and random horizontal flip augmentation. It was trained on datasets of 539 and 647 images (edema, cartilage lesions) with batch of 60, 170 epochs, 65-20-15% train-validation-test split. Saliency maps were generated using Grad-CAM algorithm. Results: The detection network showed excellent convergence, without overfitting at 25000 iterations (Fig. 2). The object detection showed a mean intersection over union of 0.92±0.04 on the validation dataset. Figure 3 shows cross-entropy loss and precision/recall plots of the bone marrow edema detection network with the corresponding confusion matrix shown in figure 4. It achieved sensitivity of 0.73 and specificity of 0.92 on the validation dataset. The cartilage lesion detection network had sensitivity of 0.67 and specificity of 0.68 after 13 epochs. An example of a saliency map generated during inference with the bone marrow edema classification network is shown in figure 5. Conclusions: Our results have demonstrated the feasibility of automated identification of OA degenerative changes. Automated cropping using deep detection network allowed to focus attention on the weight-bearing area of the joint and reduced the number of parameters. Transfer learning using pre-trained detection and classification checkpoints allowed to achieve good results in a few iterations, despite having an unbalanced dataset for edema classification, and a small number of images in the training set. Future work includes training and evaluating the pipeline with a significantly-larger set of clinical hip MRI exams. View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)View Large Image Figure ViewerDownload Hi-res image Download (PPT)

Diagnostic issue on spontaneous osteonecrosis of medial tibial plateau.

To the Editor: I read with great interest the recent report of Yang et al[1], “Clinical Characteristics and Treatment of Spontaneous Osteonecrosis of Medial Tibial Plateau: A retrospective case study” (published on November 5, 2018, Chin Med J, page 2544–2550), because there have been very few reports on isolated spontaneous medial tibial plateau osteonecrosis and little is known about osteonecrosis of the tibial plateau. I would like to comment on diagnostic issues in this letter. Osteonecrosis of the knee can be a devastating disease that leads to end-stage arthritis of the knee. The knee is the second most commonly affected site after the hip.[2] Spontaneous osteonecrosis of the knee (SPONK) involving medial femoral condyle was described as a distinct entity by Ahlback et al in 1968[3] and is also called idiopathic or primary osteonecrosis to distinguish it from secondary osteonecrosis, which is associated with corticosteroid therapy, blood dyscrasias, Gaucher disease, caisson disease,[4] and other rare conditions, for example, laser-assisted arthroscopic chondroplasty.[5] The condition usually involves a single condyle, most often the medial femoral condyle, affected in 94% of the cases and can also occur in the lateral femoral condyle or in the tibial plateaus.[6] Involvement of the tibial plateau, which was first reported in the French literature by d’Angelijan et al[7] in 1967 and was described in the English literature by Houpt et al[8] is less common. Only 2% of osteonecrosis around the knee may affect the tibial plateau. The medial tibial plateau is more frequently affected than the lateral.[9] Therefore, to our knowledge, it remains a rare cause of knee pain. In the article, the case group contains 22 patients in 15 months (from March 2015 to June 2016), it means real prevalence may be underestimated. Magnetic resonance imaging (MRI) is both sensitive and specific for recognizing SPONK of both medial femoral condyle and tibial plateau and recommended for detection of the disease, due to its high sensitivity in detecting bone marrow edema.[10] MRI characteristics include a diffuse area of hyperintensity widespread into the metaphysics on T2-weighted images, the focal subchondral area of low signal intensity adjacent to the subchondral bone plate on T1-weighted images and focal epiphyseal contour depressions. But the MRI-detected subchondral bone marrow lesion, comprised of fibrosis, necrosis, edema, and bleeding into fatty marrow in different proportions as well as abnormal trabeculae, is also a common finding in patients with OA.[11] In the article, the MRI images showed in Figures 2 and 5 have no typical MRI signs of spontaneous medial tibial plateau osteonecrosis, MRI T1 and T2 images show cartilage degeneration, narrow of joint space, focal bone marrow edema and formation of subchondral cysts in medial knee compartment. We think it is more likely anteromedial osteoarthritis of knee, not a typical SPONK of medial tibial plateau. Although medial unicompartmental knee arthroplasty is also appropriate surgical indication. We also noted that in the series, there are 17 patients (77%) with a Level III medial meniscus posterior root tears (MMPRT) and the lesions of 68% patients involved the central tibial plateau. Subchondral marrow edema deep to the MMPRT was described as a harbinger of meniscal root failure. Ipsilateral tibiofemoral compartment bone marrow edema and insufficiency fractures are commonly noted in the presence of posterior meniscal tears.[12] Therefore, differential diagnosis is important and the condition has not been clearly discussed. Funding This work was supported by a grant from Ministry of Science and Technology of China (No. 2017YFC0108003). Conflicts of interest None.

Dual-Energy CT of Material Decomposition Analysis for Detection with Bone Marrow Edema in Patients with Vertebral Compression Fractures

This study investigated detecting bone marrow edema (BME) in patients with vertebral compression fractures. We compared dual-energy material density analysis images to magnetic resonance imaging (MRI), which is considered the gold standard. In this retrospective study, 260 vertebral bodies from 30 patients (11 males, 19 females, mean age of 81) were assessed by MRI and dual-energy material density analysis. Diagnostic accuracy was assessed using the receiver operating characteristic (ROC) curve. Fifty-two of the 260 vertebral bodies were considered to have BME based on the dual-energy material density analysis images; 50 were deemed to have BME by MRI. ROC analysis of the dual-energy material density analysis values revealed an area under the ROC curve of 0.95 for radiologist 1, 0.97 for radiologist 2, and 0.96 for radiologist 3. A mean cutoff value of 1032.6 mg/cm3 provided an overall sensitivity of 93.0% (95% confidence intervals [CI]: 86.0%-99.9%), specificity of 98.0% (95% CI: 95.5%-99.0%), accuracy of 97.0% (95% CI: 95.2%-99.0%), positive predictive value of 95.0% (95% CI: 81.0%-97.5%), and negative predictive value of 98.0% (95% CI: 93.0%-99.9%). BME in patients with vertebral compression fractures can be detected using dual-energy material density analysis images.

The application of dual-energy computed tomography in the diagnosis of musculoskeletal disorders: a review of current concepts and applications.

With the assistance of innovations in scanner engineering and software design, dual-energy computed tomography (DECT) is an advanced imaging method that has been developed over the last decade. With its unique ability to differentiate materials by their atomic number, DECT has opened new perspectives in imaging. The principal advantages of DECT over conventional CT in the musculoskeletal setting relate to the additional information provided regarding tissue composition, artifact reduction and image optimization. In musculoskeletal imaging, uric acid material decomposition images can help identify articular deposition of uric acid crystals (in addition to the detection of uric acid renal stones). Material separation can also help detect bone marrow edema on CT in the case of trauma, algoneurodystrophy, inflammation (osteitis) or malignant bone marrow infiltrates, such as metastases. DECT also offers means to reduce the radiation exposure of patients by replacing multiphase exams with more specific single acquisitions. The first part of this article reviews the basic principles and technical aspects of DECT. The second part focuses on applications of DECT to musculoskeletal imaging including that of gout and other crystal-induced arthropathies, virtual non-calcium images for the study of bone marrow lesions, the study of collagenous structures, as well as the detection of hemosiderin and metal particles.

Usefulness of Fat Suppression Magnetic Resonance Imaging of Osteoporotic Vertebral Fractures in Preventing Subsequent Fractures After Kyphoplasty

Preoperative magnetic resonance imaging with fat suppression (FS-MRI) is useful to detect bone marrow edema in osteoporotic vertebral fractures (OVFs) and thus can improve diagnostic accuracy and influence surgical strategy for percutaneous augmentation. The role of preoperative FS-MRI in preventing subsequent fractures after balloon kyphoplasty has not been investigated in initially subclinical fractures or fractures without obvious morphologic changes. From January 2010 to December 2017, 214 consecutive patients underwent balloon kyphoplasty for painful OVFs. We defined 2 groups based on preoperative imaging (100 patients had preoperative FS-MRI and 114 patients had no MRI) and then compared baseline and surgical characteristics. The primary end point was incidence of subsequent fractures within 12 months after treatment. The 214 patients underwent kyphoplasty of 414 vertebrae. Comparing FS-MRI with no-MRI groups, spontaneous fractures occurred significantly more (58% vs. 26.3%; P < 0.001) and fractures were more often multilevel (≥ 4 levels) (15% vs. 2.6%; P= 0.001), respectively. Overall incidence of subsequent vertebral fractures was 25.7% (32% in FS-MRI, 20.2% in no-MRI groups; P= 0.048). Average time to diagnosis of subsequent fractures did not differ between the 2 groups (9.3 FS-MRI vs. 11.5 weeks no-MRI; P= 0.411). Age ≥80 years at the time of balloon kyphoplasty was associated with a higher odds ratio (2.3) for subsequent fractures within 12 months (P= 0.039). Surgical treatment according to preoperative FS-MRI did not reduce occurrence of subsequent OVFs and did not prolong fracture-free intervals within 12 months after kyphoplasty.

Axial Spondyloarthritis: Dual-Energy Virtual Noncalcium CT in the Detection of Bone Marrow Edema in the Sacroiliac Joints.

Purpose To determine the diagnostic performance of dual-energy virtual noncalcium (VNCa) CT in the detection of bone marrow edema in study participants with sacroiliitis associated with axial spondyloarthritis. Materials and Methods In this prospective study, 47 consecutive participants (mean age, 27 years; age range, 14-41 years [28 male; mean age, 24 years; age range, 14-37 years] [19 female; mean age, 29 years; age range, 17-41 years]) underwent dual-energy CT and 3.0-T MRI between April 2016 and December 2017. Two independent readers visually evaluated all sacroiliac joints for the presence of abnormal marrow attenuation on dual-energy VNCa images using a four-point classification system (0, no edema; 1, mild edema; 2, moderate edema; 3, severe edema). CT numbers on VNCa images were determined with region-of-interest-based quantitative analysis. MRI was the reference standard for presence of bone marrow edema. Results Sensitivity, specificity, and accuracy of readers 1 and 2, respectively, in the identification of bone edema at CT were 87% and 93% (48 and 51 of 55), 94% and 91% (32 and 31 of 34), and 90% and 92% (80 and 82 of 89). Interobserver agreement was excellent (κ = 0.81). CT numbers from VNCa images increased from no edema to severe edema (P < .001). The area under the receiver operating characteristic curve was 0.93 for reader 1 and 0.91 for reader 2 in differentiation of the presence of bone marrow edema from no edema. A cutoff value of -33 HU derived from reader 1 yielded overall sensitivity, specificity, and accuracy of 90% (49 of 55), 83% (28 of 34), and 87% (77 of 89) in the detection of any extent of edema in the sacroiliac joints. Conclusion Dual-energy VNCa CT images had excellent diagnostic performance in evaluation of the extent of bone marrow edema in study participants with sacroiliitis associated with axial spondyloarthritis. © RSNA, 2018 See also the editorial by Guggenberger in this issue.

Single-source dual-energy computed tomography for the assessment of bone marrow oedema in vertebral compression fractures: a prospective diagnostic accuracy study.

To evaluate the diagnostic accuracy of single-source dual-energy computed tomography (DECT) for the detection of bone marrow oedema (BME) in patients with vertebral compression fractures. Patients over 50 years of age with radiographically suspected vertebral compression fracture of the thoracic or lumbar spine were prospectively enrolled. All patients underwent DECT with sequential acquisition of 80 and 135 kVp datasets on a 320-row detector CT scanner and 1.5-Tesla magnetic resonance imaging (MRI) including T1-weighted and short-tau inversion recovery (STIR) sequences. Virtual non-calcium (VNCa) images were reconstructed using a three-material decomposition algorithm. Vertebrae with height loss in CT were scored for the presence of BME in both MRI and DECT and used to determine signal- and contrast-to-noise ratios (SNR and CNR). Contingency analysis using MRI as standard of reference and Fleiss's kappa were calculated. IRB approval was obtained. In total 192 vertebral compression fractures in 70 patients (23 men, 47 women; mean age 70.7 years (SD 9.8)) were included in our analysis. DECT showed a reader-dependent sensitivity of 72% and specificity of 70% for BME. Fleiss's kappa was .40 for DECT and .58 for MRI. T1-weighted images had significantly better SNR and CNR compared to STIR, CT, and VNCa (p < .0001); however, there was no difference between STIR and VNCa. VNCa images depict BME with adequate sensitivity and specificity and can be acquired on a single-source system. Image quality is adequate but trained readers are needed for image interpretation. • Dual-energy CT in a single-source technique can help to detect bone marrow oedema in patients with vertebral compression fractures. • However, given the inferior inter-rater reliability and limited specificity compared to MRI, experienced readers are needed for image interpretation. • Dual-energy CT of the spine has limited sensitivity for the detection of bone marrow oedema in vertebra with previous surgical intervention.

Bone marrow edema in traumatic vertebral compression fractures: Diagnostic accuracy of dual-layer detector CT using calcium suppressed images

PurposeTo evaluate calcium suppressed images (CaSupp) in dual-layer detector computed tomography (DLCT) for the detection of bone marrow edema (BME) in vertebral fractures. Materials and methodsThe retrospective study was approved by the institutional review board. 34 patients with synchronous DLCT and MRI, who were diagnosed with one or more acute vertebral fractures, were included. MRI were systematically analyzed as reference standard. Two blinded and independent readers evaluated CaSupp for vertebral BME. Additionally, both readers determined the optimal calcium suppression indices (CaSupp-I) for visualization of BME in consensus and correlated the CaSupp-I with parallel measurement of trabecular density as surrogate parameter for bone mineral density. ROI-based measurements of the contrast-to-noise ratios (CNR) were also conducted. Interrater agreement was determined by kappa-statistics. CNR were analyzed using Wilcoxon signed rank test. ResultsFifty-seven acute fractured vertebrae out of 383 vertebrae (14.9%) were found. CaSupp yielded an average sensitivity of 87% and specificity of 99%, a positive predictive value of 95%, a negative predictive value of 98% and an accuracy of 97% for the detection of fracture-associated edema. Interrater agreement was excellent (kappa 0.91). Increase in CNR of BME correlated with increasing CaSupp-I. Edema adjacent to the cortical endplates was better visualized using CaSupp-I of 70 and 80, while extensive edema was better visualized using a CaSupp-I of 90 and 100 (chi2 < 0.0001). No correlation between optimal CaSupp-I and trabecular density was found (p > 0.2). ConclusionCaSupp reconstructed from DLCT enable visualization and detection of BME in traumatic fractured vertebrae with high diagnostic accuracy using CaSupp-I of 70–100.

Three-material decomposition with dual-layer spectral CT compared to MRI for the detection of bone marrow edema in patients with acute vertebral fractures

ObjectivesTo assess whether bone marrow edema in patients with acute vertebral fractures can be accurately diagnosed based on three-material decomposition with dual-layer spectral CT (DLCT).Materials and methodsAcute (n = 41) and chronic (n = 18) osteoporotic thoracolumbar vertebral fractures as diagnosed by MRI (hyperintense signal in STIR sequences) in 27 subjects (72 ± 11 years; 17 women) were assessed with DLCT. Spectral data were decomposed into hydroxyapatite, edema-equivalent, and fat-equivalent density maps using an in-house-developed algorithm. Two radiologists, blinded to clinical and MR findings, assessed DLCT and conventional CT independently, using a Likert scale (1 = no edema; 2 = likely no edema; 3 = likely edema; 4 = edema). For DLCT and conventional CT, accuracy, sensitivity, and specificity for identifying acute fractures (Likert scale, 3 and 4) were analyzed separately using MRI as standard of reference.ResultsFor the identification of acute fractures, conventional CT showed a sensitivity of 0.73–0.76 and specificity of 0.78–0.83, whereas the sensitivity (0.93–0.95) and specificity (0.89) of decomposed DLCT images were substantially higher. Accuracy increased from 0.76 for conventional CT to 0.92–0.93 using DLCT. Interreader agreement for fracture assessment was high in conventional CT (weighted κ [95% confidence interval]; 0.81 [0.70; 0.92]) and DLCT (0.96 [0.92; 1.00]).ConclusionsMaterial decomposition of DLCT data substantially improved accuracy for the diagnosis of acute vertebral fractures, with a high interreader agreement. This may spare patients additional examinations and facilitate the diagnosis of vertebral fractures.

Diagnostic performance of dual-energy CT for the detection of bone marrow oedema: a systematic review and meta-analysis.

The aim of this systematic review and meta-analysis was to assess the sensitivity and specificity of dual-energy CT (DECT) for the detection of bone marrow oedema (BME). An electronic search of the PubMed and EMBASE databases was conducted. Bivariate modelling and hierarchical summary receiver-operating characteristic modelling were performed to evaluate the overall diagnostic performance of DECT for BME. Subgroup analysis was performed according to the assessment type (qualitative vs. quantitative) and anatomical location (spine vs. appendicular skeleton). Meta-regression analyses were performed according to the subject, study, and DECT characteristics. Twelve eligible studies (1901 lesions, 450 patients) were included. DECT exhibited a pooled sensitivity of 0.85 [95% confidence interval (CI): 0.78-0.90] and a pooled specificity of 0.97 (95% CI: 0.92-0.98) for BME detection. In addition, the diagnostic performance of qualitative assessment (sensitivity, 0.85; specificity, 0.97) was higher than that of quantitative assessment (sensitivity, 0.84; specificity, 0.88) of DECT findings. The diagnostic performance of DECT for the spine (sensitivity, 0.84; specificity, 0.98) and appendicular skeleton (sensitivity, 0.84; specificity, 0.93) were excellent. According to meta-regression analysis, the use of a tin filter, ≥ 2 image planes, and a slice thickness < 1 mm tended to exhibit higher sensitivity and hyperacute stage BME (< 24 h) tended to exhibit lower sensitivity. These findings indicate that DECT has excellent sensitivity and specificity for BME detection. Qualitative assessment of DECT findings obtained using a tin filter, ≥ 2 image planes, and a 0.5-1-mm slice thickness in the acute stage BME (≥24 h) is recommended for more sensitive diagnosis. • Overall, DECT is useful for the detection of BME (sensitivity, 85%; specificity-97%). • Qualitative assessment (sensitivity-85%; specificity-97%) is more accurate than quantitative assessment (sensitivity-84%; specificity-88%). • DECT showed excellent diagnostic performance for both the spine/appendicular skeleton (sensitivity-84%/84%; specificity-98%/93%).

Clinical Utility of Dual-Energy CT Analysis of Bone Marrow Edema in Acute Wrist Fractures

The purpose of this study is to determine the utility of dual-energy CT (DECT) for assessing carpal fractures and to obtain an attenuation value cutoff (in Hounsfield units) to identify bone marrow edema due to an acute carpal fracture. In this retrospective study, 24 patients who presented with wrist fractures from September 3, 2014, through March 9, 2015, underwent imaging with DECT (80 and 140 kVp). Using the three-material decomposition algorithm specific for virtual noncalcium to construct images, two radiologists identified carpal fractures and associated bone marrow edema. Readers noted the attenuation at areas with and without bone marrow edema. The cutoff value was obtained by ROC analysis and was internally validated on 13 separate patients with suspected wrist fractures. A p < 0.05 was considered statistically significant. CT attenuation was significantly higher in areas of bone marrow edema than in areas without it (p < 0.0001, t test). A cutoff of 5.90 HU allows detection of bone marrow edema associated with acute wrist fractures with 100% sensitivity and 99.5% specificity, compared with visual DECT interpretation. In the 13 validation cases, the cutoff of 5.90 HU identified bone marrow edema with 100% accuracy, compared with visual interpretation. Kappa values were 0.83 between the two readings by reader 1, and 0.73 and 0.96 comparing the two readings of reader 1 with the reading by reader 2. DECT is a useful tool for identifying bone marrow edema in the setting of acute wrist fractures, providing an alternative to MRI. A cutoff value of 5.90 HU can be used for accurate diagnosis and exclusion of carpal fractures.

Imaging Features of Symptomatic Hypertrophic Tuberculum Peroneum.

Objective:The aim of this article is to review the clinical and imaging features of symptomatic hypertrophic (TP) in a cohort of symptomatic patients.Materials and Methods:Twenty-three patients with chronic lateral ankle pain were retrospectively included in our study group. Patients underwent ultrasound (US), (cone beam) computed tomography (CB)CT or magnetic resonance (MR) examination or a combination of these examinations with a standardized protocol. Patients with an underlying fracture were excluded. The following parameters were recorded: clinical history, size of the TP on different imaging modalities, presence and grade of peroneus brevis/longus tenosynovitis and the presence of bone marrow edema at the os calcaneus on magnetic resonance imaging (MRI).Results:The mean width of the hypertrophic TP was 5.6 mm. Combined tenosynovitis of the peroneus longus (PL) and brevis tendon (PB) was most common, followed by isolated PL and finally PB tenosynovitis. Grade 1 tenosynovitis was most common. BME was present in 53% of the cases.Conclusion:The width of the TP is may be evaluated on the (oblique) coronal US, (CB)CT or non-fat suppressed MR images. Both US and MRI may detect and grade involvement of the peroneal tendons. By the use of fluid sensitive sequences, MRI may be of additional value to detect bone marrow edema as result of repetitive friction.

Advancements in Dual-Energy CT Applications for Musculoskeletal Imaging

Dual-energy computed tomography (DECT) has become a unique highly useful imaging modality in musculoskeletal (MSK) radiology practice. In this article, we provide a concise overview of the four main applications for DECT in (MSK) imaging: monosodium urate (Gout) detection, metal artifact reduction, bone marrow edema detection, and collagen imaging. We also highlight the recent studies published in radiology and rheumatology literature. Virtual monoenergetic images performed by utilizing DECT, particularly with the use of metal artifact reduction algorithm software, deliver superior image quality and have an impact on the assessment of the bone–metal interface. Regarding gout detection, DECT is a reliable, non-invasive diagnostic method to establish the diagnosis of gout that has been validated in the recent years. DECT has been incorporated into ACR/EULAR 2015 Gout Classification Criteria. DECT continues to play an important role in musculoskeletal radiology practice. Further research is required to validate some of the more recent and novel applications, for example, the collagen imaging application to compare its sensitivity and specificity in detecting tears and other tendon- and ligament-related pathologies as compared to MRI.

Meta-analysis of dual-energy computed tomography virtual non-calcium imaging to detect bone marrow edema

ObjectiveThis meta-analysis aimed to evaluate the accuracy of dual-energy CT (DECT) virtual non-calcium (VNC) imaging for the detection of bone marrow edema (BME). MethodsA systematic literature search up to March 2017 was performed to find relevant original studies. Two reviewers independently selected studies, assessed literature quality, and extracted data. Pooled sensitivity, specificity, area under receiver operating characteristic (AUROC) curve, and other measures of DECT accuracy for detecting BME were calculated using random effects models. Risk of heterogeneity was assessed for the appropriateness of meta-analysis. ResultsFourteen studies involving 2205 regions of vertebrae, hips, knees, and ankles were included. To evaluate the accuracy of BME detection using DECT, calculations were performed to obtain a pooled sensitivity of 0.812 (95% confidence interval [CI], 0.780–0.841) and specificity of 0.951 (95% CI, 0.940–0.960). The AUROC value was 0.9635. The major potential cause of heterogeneity was bone position. No significant publication bias was present. ConclusionDECT VNC imaging gives very good diagnostic performance for BME detection and will likely be an important and common modality for acute assessment in the future.

Vertebral Compression Fractures: Third-Generation Dual-Energy CT for Detection of Bone Marrow Edema at Visual and Quantitative Analyses.

Purpose To assess the diagnostic performance of a third-generation dual-energy computed tomographic (CT) virtual noncalcium (VNCa) technique for detection of traumatic bone marrow edema in patients with vertebral compression fractures. Materials and Methods This prospective study was approved by the institutional review board. Informed consent was obtained from all participants. Twenty-two consecutive patients with 37 morphologic vertebral fractures were studied between October 2015 and May 2016. All patients underwent dual-energy CT (90 kV and 150 kV with a tin filter) and 3-T magnetic resonance (MR) imaging. Two independent readers visually evaluated all vertebral bodies (n = 163) for the presence of abnormal bone marrow attenuation on VNCa images by using color-coded maps and performed a quantitative analysis of CT numbers on VNCa images. MR images served as the reference standard. CT numbers were subjected to receiver operating characteristic analysis to calculate cutoff values. Results In the visual analysis, VNCa images had an overall sensitivity of 64.0%, specificity of 99.3%, accuracy of 93.9%, positive predictive value of 94.1%, and negative predictive value of 93.8%. The interobserver agreement was excellent (κ = 0.85). CT numbers obtained from VNCa images were significantly different in vertebral bodies with and without edema (P < .001). Receiver operating characteristic analysis revealed an area under the curve of 0.922. A cutoff value of -47 provided sensitivity of 92.0%, specificity of 82.6%, accuracy of 84.0%, positive predictive value of 48.9%, and negative predictive value of 98.3% for the differentiation of edematous vertebral bodies. Conclusion Visual and quantitative analyses of dual-energy VNCa images showed excellent diagnostic performance for assessing traumatic bone marrow edema in vertebral compression fractures. © RSNA, 2017 Online supplemental material is available for this article.

Primary exploration of energy spectral CT water-based material decomposition technology for the detection of bone marrow edema in sacroiliitis

Objective To explore the value of water-based material decomposition images for detection of bone marrow edema (BME) in sacroiliitis with energy spectral CT. Methods The sacroiliac (SI) joints of nine spondyloarthropathy patients with sacroiliitis (the research group) and eight healthy volunteers (the control group) were underwent MRI and energy spectral CT.The mixed energy image of energy spectral CT was reconstructed to be mono energy image.Then, the mono image was divided into water-based image and calcium image by material divided and analyzed software.The SI para-articular marrow region water-calcium relative concentration of research group was compared with that of control group.The BME diagnosis efficiency and optimal water-based concentration of energy spectral CT was analyzed by receiver operating characteristic (ROC) curve.Then, the sensitivity, specificity, positive likelihood ratio and negative likelihood ration were calculated. Results The water-based concentration of BME in research group (1 067.43±10.84)g/L was higher than that of control group (1 039.43±8.01)g/L(t=-3.14, P=0.003). Meanwhile, the calcium-based concentration of research group (68.98±20.53)g/L was not different from control group (78.03±26.39)g/L(t=1.88, P=0.066). ROC curve showed that the diagnosis efficiency was medium as the area of under curve was 0.75.When the optimal concentration of water-based was 1 052.00g/L, the diagnosis efficiency was the best.The sensitivity and specificity was 84.00%, 62.50% respectively. Conclusion There are reference value and potential clinical value with energy spectral CT water-based concentration detection for diagnosis BME in patients with sacroiliitis. Key words: Sacroiliac joint; Bone marrow edema; Tomography, X-ray computed; Energy spectral