Soft tissue tumor imaging in adults: whole-body staging in sarcoma, non-malignant entities requiring special algorithms, pitfalls and special imaging aspects. Guidelines 2024 from the European Society of Musculoskeletal Radiology (ESSR).

OBJECTIVES: The revised European Society of Musculoskeletal Radiology (ESSR) consensus guidelines on soft tissue tumor imaging represent an update of 2015 after technical advancements, further insights into specific entities, and revised World Health Organization (2020) and AJCC (2017) classifications. This second of three papers covers algorithms once histology is confirmed: (1) standardized whole-body staging, (2) special algorithms for non-malignant entities, and (3) multiplicity, genetic tumor syndromes, and pitfalls. MATERIALS AND METHODS: A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements that had undergone interdisciplinary revision were scored online by the level of agreement (0 to 10) during two iterative rounds, that could result in 'group consensus', 'group agreement', or 'lack of agreement'. RESULTS: The three sections contain 24 statements with comments. Group consensus was reached in 95.8% and group agreement in 4.2%. For whole-body staging, pulmonary MDCT should be performed in all high-grade sarcomas. Whole-body MRI is preferred for staging bone metastasis, with [18F]FDG-PET/CT as an alternative modality in PET-avid tumors. Patients with alveolar soft part sarcoma, clear cell sarcoma, and angiosarcoma should be screened for brain metastases. Special algorithms are recommended for entities such as rhabdomyosarcoma, extraskeletal Ewing sarcoma, myxoid liposarcoma, and neurofibromatosis type 1 associated malignant peripheral nerve sheath tumors. Satisfaction of search should be avoided in potential multiplicity. CONCLUSION: Standardized whole-body staging includes pulmonary MDCT in all high-grade sarcomas; entity-dependent modifications and specific algorithms are recommended for sarcomas and non-malignant soft tissue tumors. CLINICAL RELEVANCE STATEMENT: These updated ESSR soft tissue tumor imaging guidelines aim to provide support in decision-making, helping to avoid common pitfalls, by providing general and entity-specific algorithms, techniques, and reporting recommendations for whole-body staging in sarcoma and non-malignant soft tissue tumors. KEY POINTS: An early, accurate, diagnosis is crucial for the prognosis of patients with soft tissue tumors. These updated guidelines provide best practice expert consensus for standardized imaging algorithms, techniques, and reporting. Standardization can improve the comparability examinations and provide databases for large data analysis.

Soft tissue tumor imaging in adults: European Society of Musculoskeletal Radiology-Guidelines 2023-overview, and primary local imaging: how and where?

OBJECTIVES: Early, accurate diagnosis is crucial for the prognosis of patients with soft tissue sarcomas. To this end, standardization of imaging algorithms, technical requirements, and reporting is therefore a prerequisite. Since the first European Society of Musculoskeletal Radiology (ESSR) consensus in 2015, technical achievements, further insights into specific entities, and the revised WHO-classification (2020) and AJCC staging system (2017) made an update necessary. The guidelines are intended to support radiologists in their decision-making and contribute to interdisciplinary tumor board discussions. MATERIALS AND METHODS: A validated Delphi method based on peer-reviewed literature was used to derive consensus among a panel of 46 specialized musculoskeletal radiologists from 12 European countries. Statements were scored online by level of agreement (0 to 10) during two iterative rounds. Either "group consensus," "group agreement," or "lack of agreement" was achieved. RESULTS: Eight sections were defined that finally contained 145 statements with comments. Overall, group consensus was reached in 95.9%, and group agreement in 4.1%. This communication contains the first part consisting of the imaging algorithm for suspected soft tissue tumors, methods for local imaging, and the role of tumor centers. CONCLUSION: Ultrasound represents the initial triage imaging modality for accessible and small tumors. MRI is the modality of choice for the characterization and local staging of most soft tissue tumors. CT is indicated in special situations. In suspicious or likely malignant tumors, a specialist tumor center should be contacted for referral or teleradiologic second opinion. This should be done before performing a biopsy, without exception. CLINICAL RELEVANCE: The updated ESSR soft tissue tumor imaging guidelines aim to provide best practice expert consensus for standardized imaging, to support radiologists in their decision-making, and to improve examination comparability both in individual patients and in future studies on individualized strategies. KEY POINTS: • Ultrasound remains the best initial triage imaging modality for accessible and small suspected soft tissue tumors. • MRI is the modality of choice for the characterization and local staging of soft tissue tumors in most cases; CT is indicated in special situations. Suspicious or likely malignant tumors should undergo biopsy. • In patients with large, indeterminate or suspicious tumors, a tumor reference center should be contacted for referral or teleradiologic second opinion; this must be done before a biopsy.

Can MRI knee joint measurements predict the population at risk of ACL injury?

BACKGROUND: Anterior cruciate ligament (ACL) injuries have been increasing significantly over time. The relationship between the ACL injury and the knee joint structures is poorly understood. The purpose of this study is to examine whether the measurements of different structures in the knee joint are linked with ACL injury in affected patients. METHODS: This retrospective case-control study included patients who suffered from ACL tears and underwent magnetic resonance imaging (MRI). A control group of patients with no knee pathologies on MRI was included. Fourteen knee variables, including lateral meniscus (LM) posterior horn height, length, depth, and volume; medial meniscus (MM) posterior horn height, length, depth, and volume; lateral and medial (MFC) femoral condyle sphere diameter; lateral and medial tibial plateau length; and patella tendon horizontal and vertical diameter, were collected. A multivariate logistic regression including LM posterior horn depth, MM posterior horn length, MM volume, MFC sphere diameter, and patella tendon horizontal diameter and receiver operating characteristic curve, was used to compare the two groups. RESULTS: A total of 85 patients were included in our study; 54 suffered from ACL injuries and 31 as a control group with normal knee MRI. Logistic regression revealed that increased LM posterior horn depth (OR = 1.27; 95% CI = 1.03-1.56; p = 0.028), decreased MM posterior horn length (OR = 0.71; 95% CI = 0.55-0.93; p = 0.013), and MFC sphere diameter (OR = 1.20; 95% CI = 1.01-1.43; p = 0.035) were independent risk factors for ACL rupture. The MFC sphere diameter yielded the highest area under the curve: 0.747 (95% CI, 0.632-0.862). No difference was found in the other measurements between the two groups. CONCLUSIONS: Concerning the difference in anatomical variations, the lateral meniscus posterior horn depth and medial femoral condyle sphere diameter were higher, while medial meniscus posterior horn length was lower in patients with an ACL injury. These structural knee measurements could have a possible increase in the likelihood of sustaining an ACL injury and can be used by clinicians to predict ACL injury.

Bone Scan in Identification, Assessment of Initial Extent and Response to Therapy in Polymyositis.

This is a 51-year-old male who presented with abdominal pain, bilateral proximal upper and lower extremities pain and weakness, and decreased urine output with abnormal kidney function test; Urea and creatinine levels were elevated at 231.5 mg/dl and 11.05 mg/dl, respectively. Initial bone scan showed increased uptake within several muscles suspicious for polymyositis, this was confirmed by biopsy of the right triceps, identified by bone scan as the best superficial biopsy site. Pelvis and thigh MRI demonstrated diffuse hyperintense signal on fluid sensitive sequences involving several muscles. Renal biopsy showed acute tubular injury. He was treated with steroids resulting in significant improvement. A repeat bone scan showed near complete resolution of the muscular uptake seen at presentation. This case nicely illustrates the role of bone scanning in the initial recognition and determination of the extent of polymyositis with identification of a suitable biopsy site as well as assessment of response to treatment.

The Stieda fracture revisited.

OBJECTIVE: This study aimed to evaluate injury patterns associated with Stieda avulsion fractures of the medial femoral condyle at the attachment of the proximal MCL. MATERIALS AND METHODS: Knee radiographs and MRI scans of 11 patients with Stieda fractures were evaluated by two fellowship-trained MSK radiologists for fracture origin, integrity of the deep and superficial components of the MCL, medial retinacular structures, posterior oblique ligament, other ligamentous injuries, meniscal tears, and osteochondral injuries. The mechanism of injury and subsequent clinical management were recorded. RESULTS: Eight Stieda fractures only involved the meniscofemoral fibers of the deep MCL, two larger Stieda fractures related to both superficial and deep layers, and one fracture only involved the superficial layer. Posteromedial retinacular structures and posterior oblique ligament were injured in all cases. Eight had high-grade ACL injuries, but none had high-grade PCL nor FCL injuries. The proximal anterolateral ligament was injured in seven, including two with associated Segond fractures. Other injuries included posterolateral corner injuries in six, meniscal injuries in seven, and additional fractures in nine, most commonly ACL-associated impaction fractures in the lateral tibiofemoral compartment. None had high-grade chondral injury. None of the Stieda fractures were treated surgically, but four underwent subsequent ACL reconstruction. CONCLUSION: Stieda fractures most commonly involved the deep fibers of the MCL and were accompanied by moderate-to-high-grade injury of other MCL components. There was a high association with other ligamentous injuries, particularly the posterior medial retinacular structures, posterior oblique ligament, and ACL, and many were associated with additional fractures.

Soft Tissue Sarcoma Follow-up Imaging: Strategies to Distinguish Post-treatment Changes from Recurrence.

Soft tissue sarcomas encompass multiple entities with differing recurrence rates and follow-up intervals. The detection of recurrences and their differentiation from post-therapeutic changes is therefore complex, with a central role for the clinical radiologist. This article describes approved recommendations. Prerequisite is a precise knowledge of the current clinical management and surgical techniques. We review recurrence rates and treatment modalities. An adequate imaging technique is paramount, and comparison with previous imaging is highly recommended. We describe time-dependent therapy-related complications on magnetic resonance imaging compared with the spectrum of regular post-therapeutic changes. Early complications such as seromas, hematomas, and infections, late complications such as edema and fibrosis, and inflammatory pseudotumors are elucidated. The appearance of recurrences and radiation-associated sarcomas is contrasted with these changes. This systematic approach in follow-up imaging of soft tissue sarcoma patients will facilitate the differentiation of post-therapeutic changes from recurrences.

Chest CT scan features from 302 patients with COVID-19 in Jordan.

OBJECTIVE: To study non-enhanced computer tomographic features of chest imaging in 302 patients with Corona Virus Disease 2019 (COVID-19) in Jordan. MATERIAL AND METHOD: A retrospective analysis of non-enhanced computer tomographic scans has been performed in the main center for patients diagnosed with COVID-19 in Prince Hamzah Hospital for those scanned from 13th of March 2020 to 13th of May 2020. Included scans were routinely performed during 24-hs of admission apart from having respiratory complaint. CT protocol included non-enhanced 1 mm slice thickness by Philips Brilliance Big Bore scanner (Philips; Amsterdam, Netherlands).All computer tomographic scans were reviewed by two senior radiologists with more than 8 years of experience each and senior registrar.Several factors have been thoroughly studied including patient age, gender, positive versus negative pulmonary findings, laterality of lung involvement, lobar distribution, pattern of pulmonary changes on initial and follow-up scans. RESULTS: The total number of patients evaluated was 302. There were 188 men and 114 women studied. Among the totally studied 302 cases; 181 cases (59.9 %) showed no pulmonary changes.Positive findings were present in 121 patients with a total number of 191 computer tomographic scans including initial and follow-up scans. Positive findings were present in 51 female and 70 male patients (age range, 12-87 years; mean age ± standard deviation, 46.1 ± 16.5).Bilateral disease was more frequently encountered presented in 86 cases (71.1 %), while unilateral disease showed two times more predilection for the right lung compared to the left. The incidence of lobar involvement in descending order: right lower (75.2 %), left lower (71.9 %), right upper (62.8 %), left upper (60.3 %) and right middle (50.4 %). The incidence of the affected lobes on the initial scans were as follow: one lobe (24 %), two lobes (10.7 %), three lobes (9.1 %), four lobes (16.5 %) five lobes (36.4 %). In cases with single lobar involvement (24 %); the left upper and right middle lobes showed lowest incidence of involvement accounting for 10.3 % & 13.8 %, respectively; on the other hand, in cases with four lobar involvement (16.5 %); the right middle lobe was most commonly spared in two third of cases (63.2 %).Several initial patterns of the pulmonary changes resulting from Corona Virus Disease 2019 (COVID-19) were present with a descending order; ground-glass pattern (96.7 %), lenticular pattern (32.2 %), Halo sign (15.7 % %), rounded (14.9 %), nodular (10.7 %), ground-glass with consolidation (8.3 %), tree-in-bud (1.7 %) and pleural effusion (1.7 %). Pathologically-enlarged lymph node was not a feature of COVID-19.The total number of patients with positive findings having follow-up scans was 57 including single (45 patients) versus two (12 patients) follow-up scans. Initial follow up scans showed regression and progression of the pulmonary changes in 35 and 22 patients, respectively.A remarkable pattern was seen in almost all regressed cases that showed patchy reticular pattern changes with septal thickening which was referred to "pulmonary synapses" (34 patients) with only one patient showed complete resolution of the parenchymal changes. Patterns seen in progressed cases were lenticular ground-glass (63.6 %) vs patchy ground-glass (36.4 %) patterns. CONCLUSION: Computer tomographic scan of the chest is a principal diagnostic measure for Corona Virus Disease 2019 (COVID-19). The pulmonary changes showed more propensity being bilateral disease and affecting the lower lobes, while the right middle lobe was the least likely involvement. Several pattern of pulmonary changes can be seen on initial scans including ground glass, consolidation, Halo sign, lenticular, nodular, pleural effusion and tree-in-bud patterns. The tree-in-bud is first-time described pattern of COVID-19 in the current article and thought to be an excluding criterion. In follow-up scans; the lenticular and patchy ground-glass patterns were present in cases with disease progression, compared with "pulmonary synapses" pattern encountered in cases with disease regression.

Avulsion Injuries of the Pelvis and Hip.

BACKGROUND: Avulsion injuries of the pelvis and hip region are typical injuries in adolescent athletes but can be found in adults as well. Typical sites for avulsion injuries include the origin/insertion of tendons and ligaments. Among adolescents, the not yet ossified apophysis is also frequently involved. The pelvis and hip are especially prone to such injuries due to their complex musculotendinous anatomy. Clinical history and physical examination in combination with the recognition of typical imaging findings are essential for correct diagnosis of these mostly acute, but sometimes also chronic injuries. METHODS: This review article describes typical avulsion injuries of the pelvis and hip and illustrates common radiological findings. Taking current literature into account, there is a special focus on the trauma mechanism, clinical examination, typical imaging findings and clinical management. RESULTS AND CONCLUSION: Detailed knowledge of musculotendinous anatomy and typical injury mechanisms allows a correct diagnosis of avulsion injuries often only based on clinical examination and radiographic findings. Further imaging with ultrasound and MRI may be necessary to evaluate tendon retraction in non-osseous avulsion injuries and extent of soft-tissue damage. Knowledge of potential complications of acute/chronic injuries can help to avoid unnecessary examinations or invasive interventions. Conservative management of avulsion injuries usually leads to functionally good results. However, in the case of competitive athletes, relatively wide bone fragment dislocation or marked tendon retraction, operative re-fixation may be considered in order to expedite the rehabilitation process. KEY POINTS: · Avulsion injuries are common injuries at the pelvic region especially in adolescent athletes, due to not yet ossified apophysis.. · Excellent anatomical knowledge is essential for proper diagnostic evaluation and predicting the mechanism of injury.. · Imaging plays a crucial role in diagnosing avulsion injuries starting from X-Ray and using MRI and CT for anatomical details by utilizing multiplanar capabilities.. CITATION FORMAT: · Albtoush OM, Bani-Issa J, Zitzelsberger T et al. Avulsion Injuries of the Pelvis and Hip. Fortschr Röntgenstr 2020; 192: 431 - 440.

Intermetatarsal bursitis as first disease manifestation in different rheumatological disorders and related MR-imaging findings.

Metatarsalgia defined as pain at the plantar aspect of the forefoot. Intermetatarsal bursitis is considered one potential soft-tissue cause of metatarsalgia that is presumably under-estimated, under-investigated, and, consequently, often misdiagnosed. To assess the role of MRI in the elucidation of the cause of metatarsalgia in patients with different autoimmune disorders presenting primarily with this symptom and to present the accompanying clinical and radiological findings of intermetatarsal bursitis. Retrospective evaluation of the medical records of patients with different rheumatological conditions claiming primarily of pedal pains suggests metatarsalgia and who underwent, therefore, all magnetic resonance imaging between March 2010 and April 2018. Of them, six patients fulfilled these criteria and were diagnosed subsequently with intermetatarsal bursitis. Several underlying autoimmune conditions were diagnosed. All patients were clinically assessed by the squeeze test and radiologically investigated with MRI; three patients underwent additional sonography. All patients presented intermetatarsal bursitis as first disease manifestation. The number of involved bursae ranged from one to three on one side. The main MR findings were distension of the intermetatarsal bursa with increased signal intensity on T2-weighted and post-contrast fat saturation T1-weighted images. Most frequent locations were the second and third intermetatarsal spaces. The size of the intermetatarsal bursitis and its plantar extension were correlated in all patients. Intermetatarsal bursitis can potentially be the first manifestation of different rheumatological diseases. Awareness of this potential association as well as cognizance of its imaging findings can help for making a more accurate and prompt earlier diagnosis of the underlying disease changing also the therapeutic approach.

Advanced Virtual Monoenergetic Imaging: Improvement of Visualization and Differentiation of Intramuscular Lesions in Portal-Venous-phase Contrast-enhanced Dual-energy CT.

PURPOSE: To evaluate the effect of advanced monoenergetic imaging (MEI+) postprocessing algorithm on the visualization of various intramuscular lesions on portal-venous-phase contrast-enhanced dual-energy computed tomography (DECT). MATERIAL AND METHODS: Thirty-nine patients (64.3 ± 11.1 years; 26 males) with various intramuscular lesions ranging from malignancy, bleeding, inflammation, edematous changes, and benign neoplasms were included and underwent DECT (100/Sn150kV). Postprocessing with MEI+ technique was used to reconstruct images at four different keV levels (40, 60, 80, 100) and compared to the standard portal-venous-phase CT (CTpv) images. Image quality was assessed qualitatively (conspicuity, delineation, sharpness, noise, and confidence) by two independent readers using 5-point Likert scales, 5 = excellent; as well as quantitatively by calculating signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR), and area under the receiver operating characteristic (ROC) curve (AUC) for lesion characterization. RESULTS: Highest lesion enhancement and diagnostic confidence were observed in MEI+ 40 keV, with significant differences to CTpv (p < 0.001), as well as for malignant lesions (highest conspicuity, noise, and sharpness in MEI+ 40 keV; p < 0.001). CNR calculations revealed highest values for MEI+ 40 keV followed by 60 keV with significant differences to CTpv, and increasing energy levels. ROC analysis showed highest diagnostic accuracy for 40-keV MEI+ datasets regarding the detection of malignant/benign lesions with AUC values of 98.9% (95%-confidence interval: 96.5, 100) and a standard error of 1.2, further AUC values decreased to 83.6% for MEI+100. CONCLUSION: MEI+ at low keV levels can significantly improve lesion detection of benign versus malignant intramuscular entities in patients undergoing portal-venous-phase DECT scans due to increased CNR.

Avulsion fracture of the medial collateral ligament association with Segond fracture.

The Segond fracture is a tibial avulsion injury of the insertion of the middle third of the lateral capsular ligament that is typically associated with anterior cruciate ligament and meniscal tears. The classically assigned mechanism of injury is a combination of internal rotation and varus stress. We report two cases of Segond fractures that presented with a variant pattern including osseous avulsion injuries of the medial collateral ligament at the femoral origin, anterior cruciate ligament tear, and pivot shift-type osseous contusion pattern, suggesting an alternative mechanism of injury that includes dominant valgus stress and external rotation components. Awareness of this pattern may aid radiologists, surgeons, and sport medicine physicians in the accurate diagnosis of this injury complex and initiation of appropriate treatment in a timely fashion.