Osteosarcomas (OTS) represent the most common primary bone cancer diagnosed in adolescents and young adults. Despite remarkable advances, there are no objective molecular or imaging markers able to ...predict an OTS outcome at diagnosis. Focusing on biomarkers contributing broadly to treatment resistance, we examine the interplay between the tumor-associated macrophages and intra-tumor hypoxia.
Radiological and immunohistochemical (IHC) data were correlated with the outcome in a retrospective and monocentric cohort of 30 pediatric OTS. We studied hypoxic (pS6, phospho-mTor, HIF-1α and carbonic anhydrase IX (CAIX)) and macrophagic (CD68 and CD163) biomarkers.
The imaging analyses were based on MRI manual volumetric measures on axial post-contrast T1 weighted images, where, for each tumor, we determined the necrotic volume and its ratio to the entire tumor volume. When they were above 50 cm
and 20%, respectively, they correlated with a worse overall survival (
= 0.0072 and
= 0.0136, respectively) and event-free survival (
= 0.0059 and
= 0.0143, respectively). IHC assessments enable a significant statistical link between HIF-1α/CAIX hyper-expressions, CD68+ cells and a worse outcome, whereas activation of mTor pathway was linked to a better survival rate and CD163+ cells.
This study evidenced the links between hypoxia and immunity in OTS, as their poor outcome may be related to a larger necrotic volume on diagnostic MRI and, in biopsies, to a specific IHC profile.
Fractures of the calcaneus and talus are severe injuries that usually result from high-energy trauma. The calcaneus and talus are essential for the transmission of body weight, so an optimal ...reduction and/or fixation of fractures is required to prevent disabling consequences. These fractures almost always have an articular involvement, and an anatomical reduction is required; any residual step-off would lead to joint incongruity and secondary arthrosis.The aims of imaging are first, to guide management by describing the fracture characteristics (e.g., location, displacement, fragments, articular involvement, soft tissue compromise), and second, to detect early and late surgical complications (e.g., infection, malunion, nonunion, arthrosis, hardware issues). Although radiographs remain the first-line imaging modality for the screening of ankle and foot trauma, computed tomography is almost always required for the initial management and follow-up of the patient.
Objective
We hypothesised that the orientation of the fracture line in the cervical vertebral arch depends on the traumatic mechanism, specifically focusing on frontal oblique spino-laminar fractures ...to determine if this pattern can serve as an indicator of a hyperextension mechanism of injury of the cervical spine.
Materials and methods
We reviewed the imaging records of 114 adult patients admitted to the emergency department of the Strasbourg University Hospital for severe polytrauma between January 2016 and December 2021 and who presented with a fracture of the posterior vertebral arch of the lower cervical spine on the whole-body CT scan. A radiology resident (R1) and a musculoskeletal radiologist (R2) independently read the CT scans to determine the type of vertebral arch fracture; inter- and intra-observer agreements were calculated using Cohen’s Kappa test. Two musculoskeletal radiologists (R2 and R3) then reviewed the CT scans and possible MRIs to identify specific hyperextension injuries of the cervical spine. The association between frontal oblique spino-laminar fracture and hyperextension injuries was assessed using chi
2
test.
Results
Thirty-five patients had frontal oblique spino-laminar fractures of the cervical spine. These fractures were significantly associated (
p
= 0.001) with hyperextension injuries of the cervical spine. The inter- and intra-observer agreements for the identification of these spino-laminar fractures were very good (0.86 (0.75–0.96) and 0.90 (0.81–0.99)).
Conclusion
Frontal oblique spino-laminar fractures are easily recognisable on CT scans and significantly associated with other traumatic injuries known as resulting from hyperextension. Their identification should lead to a search for potential associated unstable vertebral disco-ligamentous injuries with MRI.
Objective
The goal of this study is to determine whether smooth kernel reconstructions are more sensitive than sharp kernel ones for the detection of sacral stress fractures (SF) using MRI as the ...reference standard.
Materials and methods
This retrospective study included 100 subjects in whom CT and MR of the pelvis were performed for a clinical suspicion of SF from January 2014 to May 2020 in our institution. MR was used as the reference standard for the presence of SF. Smooth and sharp kernel CT datasets of the 100 patients were pooled and analyzed randomly. Three readers of various experiences in MSK imaging independently evaluated the axial CT images for the presence of a SF.
Results
SF was present on MR in 31 patients (22 women, 9 men; mean age 73.6 ± 19.6) and absent in 69 (48 women, 21 men; mean age 68.8 ± 19.0). Depending on readers, sensitivities ranged from 58 to 77% for the smooth kernel and from 52 to 74% for the sharp kernel reconstructions. For each reader, sensitivities (as well as negative predictive values) of CT were slightly greater on the smooth kernel reconstructions.
Conclusion
The use of smooth kernel reconstructions improved the sensitivity of CT for the detection of SF compared to the sharp kernel reconstructions usually used and regardless of the experience of the radiologist. Smooth kernel reconstructions should, therefore, be scrutinized in patients with suspicion of SF.
Objective
Radiographs are first-line imaging in ankle trauma but lack sensitivity to detect ligamentous injuries and undisplaced fractures. Our hypothesis was that ankle injuries occur in predefined ...sequences along two osteoligamentous rings, so that occult injuries non-visible on initial radiographs can be predicted. We, therefore, aimed to validate a ring model of progressive damages in the interpretation of ankle trauma radiographs.
Methods
This study retrospectively enrolled 277 adult patients that presented an acute fibular fracture on ankle radiographs between May and November 2019. Four different types of fibula fracture were differentiated, each being considered to correspond to a different mechanism of injury. Patients were classified into four groups, upon the appearance of their fibular fracture. Then, injuries to the distal tibiofibular syndesmosis, medial malleolus, and deltoid ligament (medial clear space) were assessed in each patient radiographs. Traumatic injuries were independently evaluated by a resident and an experienced MSK radiologist. For each patient, observed features were compared to those predicted by the ring concept. Inter- and intraobserver agreements were calculated.
Results
Injuries were observed according to the predictable sequence in 266 of the 277 patients (96%). In the 11 remaining patients, discordances were presumably due to undisplaced injuries to the syndesmosis or deltoid ligament. Agreements were considered very good for each evaluated item.
Conclusion
The Lauge-Hansen ring concept was found to be highly accurate and reproducible for radiographic assessment of ankle injuries. Discordances to the predicted sequence might reflect occult injuries, especially of the syndesmosis or deltoid ligament.
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•Intracranial vessel wall imaging appears useful in COVID-19 patients.•Vasculitis seems likely as imaging demonstrated vessel wall thickening with homogeneous and concentric ...enhancement.•Cerebral vasculitis seems to be one of the mechanisms at the origin of brain damage related to COVID-19.
Cerebral complications related to COVID-19 were recently reported, and the underlying mechanisms of brain damage remain uncertain, probably multifactorial. Among various hypotheses suggested, a possible vasculitis was issued but never confirmed. Herein, we aimed to describe brain MRIs focused on the intracranial vessel wall in a population of COVID-19 patients with neurologic manifestations.
Between March 1 and May 31, 2020, 69 consecutive COVID-19 patients with neurologic manifestations underwent a brain MRI allowing the study of the intracranial vessel wall at Strasbourg University hospitals and were retrospectively included. During the same period, 25 consecutive patients, without suspicion of SARS-CoV-2 infection, underwent a brain MRI urgently, with the same imaging protocols. A vasculitis seemed likely when imaging demonstrated vessel wall thickening with homogeneous and concentric enhancement.
Among the 69 COVID-19 patients included, 11 (16%) presented arterial vessel wall thickening with homogeneous and concentric enhancement, compatible with cerebral vasculitis. These neuroimaging findings were not found among the 25 patients without SARS-CoV-2 infection, and the difference was statistically significant (p = 0.03). Middle cerebral arteries, basilar artery, and posterior cerebral arteries were the most frequent vessels involved. For nine of them, imaging demonstrated ischemic or hemorrhagic complications.
Cerebral vasculitis of medium-sized vessels seems to be one of the mechanisms at the origin of brain damage related to COVID-19.
Objectives
To evaluate the performance of on-call radiology residents in interpreting alone brain and spine MRI studies performed after hours, to describe their mistakes, and to identify influencing ...factors that increased the occurrence of errors.
Methods
A total of 328 MRI examinations performed during a 13-month period (from December 1, 2019, to January 1, 2021) were prospectively included. Discrepancies between the preliminary interpretation of on-call radiology residents and the final reports of attending neuroradiologists were noted and classified according to a three-level score: level 1 (perfect interpretation or minor correction), level 2 (important correction without immediate change in patient management), or level 3 (major correction with immediate change in patient management). Categorical data were compared using Fisher’s exact test.
Results
The overall discrepancy rate (level-2 and level-3 errors) was 16%; the rate of major discrepancies (only level-3 errors) was 5.5%. The major-discrepancy rate of second-year residents, when compared with that of senior residents, was significantly higher (
p
= 0.02). Almost all of the level-3 errors concerned cerebrovascular pathology. The most common level-2 errors involved undescribed aneurysms. We found no significant difference in the major-discrepancy rate regarding time since the beginning of the shift.
Conclusions
The great majority of examinations were correctly interpreted. The rate of major discrepancies in our study was comparable to the data in the literature, and there was no adverse clinical outcome. The level of residency has an effect on the rate of serious errors in residents’ reports.
Key Points
• The rate of major discrepancies between preliminary MRI interpretations by on-call radiology residents and final reports by attending neuroradiologists is low, and comparable to discrepancy rates reported for head CT interpretations.
• The youngest residents made significantly more serious errors when compared to senior residents.
• There was no adverse clinical outcome in patient morbidity as a result of an initial misdiagnosis.
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