Detection of bone marrow oedema in knee joints using a dual-energy CT virtual non-calcium technique

Diagnostic performance of dual-energy CT in detecting bone marrow edema in lower limb joint injuries: a meta-analysis

OBJECTIVE

We aimed to evaluate the diagnostic performance of dual-energy computed tomography (DECT) in detecting bone marrow edema (BME) in patients with lower limb joint injuries.

METHODS

A thorough literature search was conducted across the PubMed, Embase, and Web of Science databases to identify relevant studies up to April 2024. Studies examining the diagnostic performance of DECT in detecting BME in lower limb joint injuries patients were included. Sensitivity and specificity were evaluated using the inverse variance method and transformed via the Freeman-Tukey double arcsine transformation. Furthermore, the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool was utilized to evaluate the methodological quality of the included studies.

RESULTS

This meta-analysis included 17 articles involving 625 patients. The pooled sensitivity, specificity, and AUC for DECT in detecting BME in lower limb joint injuries patients were 0.82 (95 % CI: 0.76-0.87), 0.95 (95 % CI: 0.92-0.97), and 0.95 (95 % CI: 0.93-0.97), respectively. The pooled sensitivity of DECT for detecting BME in knee, hip, and ankle joint injuries was 0.80, 0.84, and 0.80, with no significant difference among these joints (P = 0.55). The pooled specificity for knee, hip, and ankle injuries was 0.95, 0.97, and 0.89. Specificity differed significantly among the joints (P < 0.01), with the highest specificity in hip injuries.

CONCLUSIONS

Our meta-analysis indicates that DECT demonstrates high diagnostic performance in detecting BME in patients with lower limb joint injuries, with the highest specificity observed in hip joint injuries. To validate these findings, further larger prospective studies are necessary.

Dual-energy CT: Impact of detecting bone marrow oedema in occult trauma in the Emergency

Dual-energy computed tomography (DECT) is an advanced imaging technique that acquires data using two distinct X-ray energy spectra, typically at 80 and 140 kVp, to differentiate materials based on their atomic number and electron density. This capability allows for the enhanced visualisation of various pathologies, including bone marrow oedema (BMO), by providing high-resolution images with notable energy spectral separation while maintaining radiation doses comparable to conventional CT. DECT's ability to create colour-coded virtual non-calcium (VNCa) images has proven particularly valuable in detecting traumatic bone marrow lesions (BMLs) and subtle fractures, offering a reliable alternative or complement to MRI. DECT has emerged as a significant tool in the detection and characterisation of bone marrow pathologies, especially in traumatic injuries. Its ability to generate high-resolution images and distinguish between different tissue types makes it a valuable asset in clinical diagnostics. With its comparable diagnostic accuracy to MRI and the added advantage of reduced examination time and increased availability, DECT represents a promising advancement in the imaging of BMO and related conditions.

Diagnostic accuracy of dual-energy CT for bone marrow edema in patients with acute knee injury: a systematic review and meta-analysis

BACKGROUND

Knee injuries are prevalent, and early diagnosis is crucial for guiding clinical therapy. MRI is the diagnostic gold standard for bone marrow edema (BME) in patients with acute knee injuries, yet there are still limitations. Dual-energy CT, a possible viable replacement, is being explored (DECT).

METHODS

We systematically retrieved studies from EMBASE, Scopus, PUBMED, and the Cochrane Library and collected gray literatures. In accordance with the PRISMA-DTA standards, a systematic review was conducted between the study's initiation and July 31, 2021, utilizing an MRI reference standard and at least 10 adult patients with acute knee injuries to evaluate the diagnostic effectiveness of DECT for diagnosing BME. Two reviewers collected the study's details independently. For the meta-analysis, a bivariate mixed-effects regression model was utilized, and subgroup analysis was employed to determine the sources of variability.

RESULTS

The research included nine studies that examined 290 individuals between the ages of 23 and 53 with acute knee injuries who had DECT and MRI. Overall, the sensitivity, specificity, and AUC of the BME were 85% (95% confidence interval [CI]: 77-90%), 96% (95% CI: 93-97%), and 0.97 (95% CI: 0.95-0.98), respectively. To account for the assumed diversity of research, there were no statistically significant differences between the comparison groups in terms of specificity and sensitivity.

CONCLUSION

DECT is a viable alternative to MRI for individuals with acute knee injuries when MRI is inappropriate or unavailable.

Development of Cu application using dual-energy computed tomography for detecting medication-related osteonecrosis of the jaw

INTRODUCTION

The present study developed an application using dual-energy computed tomography (DECT) focused on Cu for detecting medication-related osteonecrosis of the jaw (MRONJ).

MATERIALS AND METHODS

First, we performed two types of phantom studies using a Cu wire syringe and pig mandible with Cu wire to detect Cu on DECT. Second, DECT examinations of 44 patients with MRONJ were performed to compare lesion and normal bone sites using single-energy CT, DECT-virtual non-calcium (VNCa), and DECT-Cu applications. Quantitative analyses of VNCa CT and CT values were performed, and a cut-off value was calculated using receiver operating characteristic analysis. Third, we compared the Cu content in the MRONJ and normal bone groups using inductively coupled plasma atomic emission spectroscopy (ICP-AES).

RESULTS

The material-specific differences in attenuation between the two different energies enabled the accurate separation of Cu from Ca in phantom studies. The sensitivity and specificity for single-energy CT, DECT-VNCa, and DECT-Cu applications were 97.7% and 2.3%, 86.4% and 81.8%, and 88.6% and 97.7%, respectively. Thus, VNCa CT values obtained on DECT-Cu application images showed the highest area under the curve value and maximal diagnostic efficacy in differentiating lesion sites from normal bone sites. On ICP-AES analyses, the Cu content was significantly higher in the MRONJ group than in the normal bone group.

CONCLUSION

DECT-Cu application demonstrated better diagnostic performance in detecting MRONJ compared with single-energy CT or DECT-VNCa.

Application of double-layer detector spectral CT calcicum supression technique in the diagnosis of traumatic bone marrow edema in the knee

Objective

To investigate the accuracy of calcicum supression (CaSupp) technique derived from double-layer detector spectral computed tomography (DSCT) in the diagnosis of traumatic bone marrow edema in the knee.

Methods

Twenty-three patients with trauma in the knee who underwent DSCT and Magnetic Resonance Imaging (MRI) in the Third Hospital of Hebei Medical University from October 2021 to March 2022 were retrospectively collected. To make the evaluation more detailed and accurate, each knee was divided into 10 partitions. Bone marrow edema in each partition of the knee was evaluated by two physicians (physician A and B) using CaSupp images combined with conventional CT-CaSupp fusion false-color images. MRI results were used as the gold standard and the accuracy of the CaSupp technique was analyzed in the diagnosis of traumatic bone marrow edema in the knee. The CaSuppCT values of the normal bone marrow area and the bone marrow edema area were delineated, and receiver operating curve (ROC curve) was drawn to find the optimal cut-off value of CaSuppCT as the quantitative parameter for the diagnosis of bone marrow edema.

Results

The diagnostic sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of physician A were 83.1 %, 98.1 %, 95.5 % and 92.1 %, respectively; those of physician B were 93.5 %, 97.4 %, 94.7 % and 96.8 %, respectively. The CaSuppCT values in the bone marrow edema areas were higher than those in the normal areas, and the difference was statistically significant. The area under the receiver operating characteristic curve (AUC) of the CaSuppCT values was 0.979, and the cut-off value was 7.05Hu*. The corresponding diagnostic sensitivity was 87.0 %, and specificity was 100.0 %.

Conclusion

The CaSupp technique derived from DSCT has high sensitivity and specificity in the detection of traumatic bone marrow edema in the knee, and can provide more imaging information for clinical practice.

Detecting Bone Marrow Edema of the Extremities on Spectral Computed Tomography Using a Three-Material Decomposition

BACKGROUND

Detecting bone marrow edema (BME) as a sign of acute fractures is challenging on conventional computed tomography (CT). This study evaluated the diagnostic performance of a three-material decomposition (TMD) approach for detecting traumatic BME of the extremities on spectral computed tomography (SCT).

METHODS

This retrospective diagnostic study included 81 bone compartments with and 80 without BME. A TMD application to visualize BME was developed in collaboration with Philips Healthcare. The following bone compartments were included: distal radius, proximal femur, proximal tibia, distal tibia and fibula, and long bone diaphysis. Two blinded radiologists reviewed each case independently in random order for the presence or absence of BME.

RESULTS

The interrater reliability was 0.84 (p < 0.001). The different bone compartments showed sensitivities of 86.7% to 93.8%, specificities of 84.2% to 94.1%, positive predictive values of 82.4% to 94.7%, negative predictive values of 87.5% to 93.3%, and area under the curve (AUC) values of 85.7% to 93.1%. The distal radius showed the highest sensitivity and the proximal femur showed the lowest sensitivity, while the proximal femur presented the highest specificity and the distal tibia presented the lowest specificity.

CONCLUSIONS

Our TMD approach provides high diagnostic performance for detecting BME of the extremities. Therefore, this approach could be used routinely in the emergency setting.

Preliminary evaluation of dual-energy CT to quantitatively assess bone marrow edema in patients with diabetic foot ulcers and suspected osteomyelitis

OBJECTIVES

The purpose of this study is to evaluate the value of dual-energy CT (DECT) with virtual non-calcium (VNCa) in quantitatively assessing the presence of bone marrow edema (BME) in patients with diabetic foot ulcers and suspected osteomyelitis.

METHODS

Patients with a diabetic foot ulcer and suspected osteomyelitis that underwent DECT (80 kVp/Sn150 kVp) with VNCa were retrospectively included. Two observers independently measured CT values of the bone adjacent to the ulcer and a reference bone not related to the ulcer. The patients were divided into two clinical groups, osteomyelitis or no-osteomyelitis, based on the final diagnosis by the treating physicians.

RESULTS

A total of 56 foot ulcers were identified of which 23 were included in the osteomyelitis group. The mean CT value at the ulcer location was significantly higher in the osteomyelitis group (- 17.23 ± 34.96 HU) compared to the no-osteomyelitis group (- 69.34 ± 49.40 HU; p < 0.001). Within the osteomyelitis group, the difference between affected bone and reference bone was statistically significant (p < 0.001), which was not the case in the group without osteomyelitis (p = 0.052). The observer agreement was good for affected bone measurements (ICC = 0.858) and moderate for reference bone measurements (ICC = 0.675). With a cut-off value of - 40.1 HU, sensitivity was 87.0%, specificity was 72.7%, PPV was 69.0%, and NPV was 88.9%.

CONCLUSION

DECT with VNCa has a potential value for quantitatively assessing the presence of BME in patients with diabetic foot ulcers and suspected osteomyelitis.

KEY POINTS

• Dual-energy CT (DECT) with virtual non-calcium (VNCa) is promising for detecting bone marrow edema in the case of diabetic foot ulcers with suspected osteomyelitis. • DECT with VNCa has the potential to become a more practical alternative to MRI in assessing the presence of bone marrow edema in suspected osteomyelitis when radiographs are not sufficient to form a diagnosis.

Dual-energy CT virtual non-calcium: an accurate method for detection of knee osteoarthritis-related edema-like marrow signal intensity

OBJECTIVES

To evaluate the performance of a dual-energy computed tomography (DECT) virtual non-calcium (VNCa) technique in the detection of edema-like marrow signal intensity (ELMSI) in patients with knee joint osteoarthritis (OA) compared to magnetic resonance imaging (MRI).

METHODS

The study received local ethics board approval, and written informed consent was obtained. DECT and MRI were used to examine 28 knees in 24 patients with OA. VNCa images were generated by dual-energy subtraction of calcium. The knee joint was divided into 15 regions for ELMSI grading, performed independently by two musculoskeletal radiologists, with MRI as the reference standard. We also analyzed CT numbers through receiver operating characteristics and calculated cut-off values.

RESULTS

For the qualitative analysis, we obtained CT sensitivity (Readers 1, 2 = 83.7%, 89.8%), specificity (Readers 1, 2 = 99.5%, 99.5%), positive predictive value (Readers 1, 2 = 95.3%, 95.7%), and negative predictive value (Readers 1, 2 = 97.9%, 98.7%) for ELMSI. The interobserver agreement was excellent (κ = 0.92). The area under the curve for Reader 1 and Reader 2 was 0.961 (95% CI 0.93, 0.99) and 0.992 (95% CI 0.98, 1.00), respectively. CT numbers obtained from the VNCa images were significantly different between regions with and without ELMSI (p < .001).

CONCLUSIONS

VNCa images have good diagnostic performance for the qualitative and quantitative analysis of knee osteoarthritis-related ELMSI.

Traumatic bone marrow lesions in dual-energy computed tomography

Traumatic bone marrow lesions (TBMLs) are considered to represent a range of concealed bone injuries, including haemorrhage, infarction, and localised oedema caused by trabecular microfracture occurring in the cancellous bone. If TBMLs are not managed timeously, they potentially cause a series of complications that can lead to irreversible morbidity and prolonged recovery time. This article reviews interesting image findings of bone marrow lesions in dual-energy computed tomography (DECT). In addition to combining the benefits of traditional CT imaging, DECT also reveals and identifies various structures using diverse attenuation characteristics of different radiographic spectra. Therefore, DECT has the capacity to detect TBMLs, which have traditionally been diagnosed using MRI. Through evaluating DECT virtual non-calcium maps, the detection of TBMLs is rendered easier and more efficient in some acute accidents.

Virtual non-calcium dual-energy CT: clinical applications

Dual-energy CT (DECT) has emerged into clinical routine as an imaging technique with unique postprocessing utilities that improve the evaluation of different body areas. The virtual non-calcium (VNCa) reconstruction algorithm has shown beneficial effects on the depiction of bone marrow pathologies such as bone marrow edema. Its main advantage is the ability to substantially increase the image contrast of structures that are usually covered with calcium mineral, such as calcified vessels or bone marrow, and to depict a large number of traumatic, inflammatory, infiltrative, and degenerative disorders affecting either the spine or the appendicular skeleton. Therefore, VNCa imaging represents another step forward for DECT to image conditions and disorders that usually require the use of more expensive and time-consuming techniques such as magnetic resonance imaging, positron emission tomography/CT, or bone scintigraphy. The aim of this review article is to explain the technical background of VNCa imaging, showcase its applicability in the different body regions, and provide an updated outlook on the clinical impact of this technique, which goes beyond the sole improvement in image quality.

Diagnostic accuracy of dual-energy CT for detecting bone marrow edema in patients with acute knee injuries: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis evaluated the diagnostic accuracy of dual-energy CT (DECT) for detecting bone marrow edema (BME) in adult patients with acute knee injuries.

METHODS

A systematic review of MEDLINE, EMBASE, Scopus, the Cochrane Library, and gray literature was performed from inception to January 31, 2020, using PRISMA-DTA guidelines. The review included studies assessing the diagnostic accuracy of DECT for detecting BME in at least 10 adult patients with acute knee injuries and with an MRI reference standard. Study details were independently extracted by two reviewers. Meta-analysis was performed using a bivariate mixed-effects regression model with subgroup analysis performed to evaluate for sources of variability. Risk of bias (ROB) was evaluated using the QUADAS-2 tool.

RESULTS

Eight studies evaluating 267 patients between the ages of 25-54 with acute knee injuries undergoing DECT and MRI were included in analysis. Summary sensitivity, specificity, and AUROC values for BME were 84% (95% confidence interval (CI) 74-91%), 96% (95% CI 93-98%), and 0.97 (95% CI 0.95-0.98), respectively. Bone-based characterization was found to have lower specificity than region-based characterization (83% (57-95%) versus 97 (96-98%), p < 0.05), but no difference in sensitivity. No other statistical differences were identified amongst study subgroups to account for presumed variability amongst studies. Most studies were rated low risk for bias and applicability concerns.

CONCLUSION

DECT is specific and accurate for detecting BME in adult patients with acute knee injuries and can be used as an alternative to MRI, particularly when MRI is contraindicated or unavailable.

Identification of bone marrow edema around the ankle joint in non-traumatic patients: Diagnostic accuracy of dual-energy computed tomography

OBJECTIVES

To evaluate the diagnostic accuracy of DECT in the identification of BME of the ankle in non-traumatic patients.

METHODS

This prospective institutional review board approved study included 40 consecutive patients (21 males and 19 females, mean age 56.8 years, SD = 11.37) that were examined using DECT and MRI in the period between April 2019 and January 2020. Two radiologists (7 and 16 years of experience) evaluated the presence of BME on DECT mages. Diagnostic accuracy values for diagnosing BME on a per-patient and on a per-partition basis analysis were calculated for DECT images by two readers (R1 and R2, with 16 and 7 years of experience, respectively), using MRI as a gold-standard for diagnosis. Inter-observer agreements were calculated with k-statistics. A p-value of <0.05 was considered as statistically significant.

RESULTS

MRI depicted BME in 29/40 patients (72.50%) and in 43/240 partitions (17.91%). The consensus reading by R1 and R2 of DECT images allowed us to achieve 89.7% sensitivity (26/29 patients) and 81.8% specificity (9/11 patients). Regarding the partitions-basis analysis, BME was depicted by DECT in 39/43 partitions (90.69% sensitivity), and ruled out in 189/197 partitions (95.93% specificity). Sensitivity and specificity for the most involved partitions (talar dome) were both 95%. The inter-observer agreement for patients' analysis was substantial (k = 0.697), whereas for the partitions' analysis, it ranged from substantial (k = 0.724) to near perfect (k = 0.950).

CONCLUSIONS

DECT can accurately diagnose BME of the ankle in a cohort of non-traumatic patients.

Diagnostic accuracy of dual-energy CT for the detection of bone marrow edema in the appendicular skeleton: a systematic review and meta-analysis

OBJECTIVES

This meta-analysis evaluated the diagnostic accuracy of dual-energy CT (DECT) for detecting bone marrow edema (BME) in the appendicular skeleton.

METHODS

A systematic review of MEDLINE, EMBASE, Scopus, the Cochrane Library, and gray literature from inception through January 31, 2020, was performed. Original articles with > 10 patients evaluating the accuracy of DECT for detecting BME in the appendicular skeleton with a reference standard of MRI and/or clinical follow-up were included. Study details were independently extracted by two reviewers. Meta-analysis was performed using a bivariate random-effects model with multivariable meta-regression. Risk of bias (RoB) was evaluated with QUADAS-2.

RESULTS

Twenty studies evaluating 790 patients for BME in the appendicular skeleton were included in analysis. The summary sensitivity, specificity, and AUC values for BME in the appendicular skeleton were 86% (95% confidence interval [CI] 82-89%), 93% (95% CI 90-95%), and 0.95, respectively. Quantitative analysis had a higher sensitivity than qualitative analysis on meta-regression (p = 0.01), but no difference in specificity (p = 0.28). No other covariates contributed to variability in accuracy (etiology (trauma vs non-trauma); location (upper vs lower extremity); and RoB). Studies demonstrated generally low or unclear RoB and applicability. Eight studies included index tests with high RoB when quantitative assessments used a retrospective cut-off value.

CONCLUSIONS

DECT demonstrates a higher specificity than sensitivity and AUC > 0.9. In scenarios where MRI availability is limited or contraindicated, DECT could be an alternative to MRI for detecting BME in the appendicular skeleton. However, limitations in sources of variability and RoB warrant continued study.

KEY POINTS

• Twenty studies evaluating 790 patients for bone marrow edema in the appendicular skeleton with dual-energy CT were included in analysis. • The summary sensitivity, specificity, and AUC values for detecting bone marrow in the appendicular skeleton were 86% (95% confidence interval [CI] 82-89%), 93% (95% CI 90-95%), and 0.95, respectively. • In scenarios where MRI availability is limited or is contraindicated, DECT could be an alternative to MRI for detecting bone marrow edema in the appendicular skeleton.

Identification of bone marrow edema of the knee: diagnostic accuracy of dual-energy CT in comparison with MRI

BACKGROUND

To assess the diagnostic accuracy of dual-energy computed tomography (DECT) in diagnosing bone marrow edema (BME) of the knee in traumatic and non-traumatic patients.

METHODS

This prospective IRB approved study included 33 consecutive patients (20 males, 13 females; mean age of 52.2 years) evaluated with DECT (80 and 150 kV) and MRI within 6 days. Two experienced radiologists qualitatively and quantitatively evaluated DECT images. The accuracy values were calculated by using receiver operator curves (ROC) and area under the curve (AUC), using MRI as the reference standard. Inter-observer and intra-observer agreement were calculated with k-statistics. A p < 0.05 was considered statistically significant.

RESULTS

MRI depicted BME in 25/33 patients (75.7%). The sensitivity, specificity, PPV, NPV, and accuracy of per-partition qualitative analysis were 92.9, 92.9, 78.2, 97.9, and 92.9%, for reader 1, and 88.2, 93.9, 79.8, 96.6, and 92.6%, for reader 2, respectively. The inter-observer agreement was substantial (k = 0.793) and the intra-observer agreement was near-perfect (k = 0.844). At the quantitative analysis, a significant difference (p < 0.001) was depicted between the density values of positive (mean 3.6 ± 25.3 HU) and negative cases (mean - 72.2 ± 45.1 HU). By using - 15 HU cutoff to identify BME, sensitivity, specificity, PPV, NPV, and accuracy of DECT were 84.7, 93.6, 78.2, 95.7, and 91.6%, respectively.

CONCLUSION

DECT can accurately identify BME of the knee.

Temporomandibular joint imaging: current clinical applications, biochemical comparison with the intervertebral disc and knee meniscus, and opportunities for advancement

Temporomandibular disorders encompass multiple pathologies of the temporomandibular joint that manifest as middle/inner ear symptoms, headache, and/or localized TMJ symptoms. There is an important although somewhat limited role of imaging in the diagnostic evaluation of temporomandibular disorders. In this manuscript, we provide a comprehensive review of TMJ anatomy, outline potentially important features of TMJ disc ultrastructure and biochemistry in comparison with the intervertebral disc and knee meniscus, and provide imaging examples of the TMJ abnormalities currently evaluable with MRI and CT. In addition, we provide an overview of emerging and investigational TMJ imaging techniques in order to encourage further imaging research based on the biomechanical alterations of the TMJ disc.