SS 1512 - Paediatric musculoskeletal and oncological imaging
SS 1512 - Paediatric musculoskeletal and oncological imagingSaturday, March 4, 14:00 - 15:30 Room: M 2 Session Type: Scientific Session Topics: Oncologic Imaging, Musculoskeletal, Paediatric Moderators: R. A. J. Nievelstein (Utrecht/NL), L. Ording Müller (Oslo/NO) Add session to my schedule In your schedule (remove)
Purpose: The purpose of this study is to assess the reliability of standard adult carpal angle measurements, specifically the scapholunate and capitolunate angles, in the assessment of the paediatric wrist in the trauma setting.
Methods and Materials: The study cohort comprised of male and female children who underwent a wrist radiograph for the evaluation of suspected wrist or forearm injuries post trauma. In order to ensure an accurate technique of carpal angle measurement, only individuals with a sufficiently ossified carpus and an adequately positioned lateral wrist radiograph were included. In addition, we determined wrist angle measurements on a gender matched adult population in order to assess if the two groups were comparable. Adults between the ages of 18-40 who underwent wrist radiographs for evaluation of suspected injury post trauma were included and similar exclusion criteria were applied.
Results: Carpal angle measurements were performed on the lateral wrist radiographs of 256 individuals between the ages of 5 and 17 years (mean 11.2 years , SD± 2.5 years). The mean scapholunate angle was 48°(SD± 7). The mean capitolunate angle was 10°(SD± 6). The mean scapholunate and capitolunate angles of the adult cohort were 49°(SD± 8°) and 11°(SD± 6°) respectively. No statistically significant difference was observed between the scapholunate or capitolunate angle measurements in the two groups (p=0.57 and p=0.92 respectively).
Conclusion: The data suggests that standard adult assessment techniques and values for scapholunate and capitolunate angle radiographic measurements are applicable to the paediatric population provided the carpus is sufficiently ossified.
Purpose: To evaluate the dose and reliability of micro-dose biplanar radiographs (BPR) in children's pangonometry.
Methods and Materials: From September 2015 to February 2016, children aged 6-18 years followed up for lower limb malalignment were prospectively included. Body mass index (BMI) was calculated for each patient. Morphotype was selected according to hip width: M1 (< 25cm), M2 (25 to 35cm), M3 (> 35cm). For each patient, standing full-length lower limb BPR were acquired using randomly either a standard low-dose protocol or a micro-dose protocol. Pangonometry was performed independently by two observers. Reliability of measured parameters was compared for each protocol and morphotype subgroups, using the intraclass correlation coefficient (ICC). For each patient, dose area product (DAP) and skin dose using two thermoluminescent dosimeters were registered.
Results: We studied 260 consecutive children (100 girls and 160 boys).The mean age was 12 years (SD: 3 yo); 74 children in M1 (mean BMI: 15.7 kg/m²), 149 in M2 (BMI: 19.8 kg/m²) and 40 in M3 (BMI: 30,2 kg/m²). In micro-dose protocol, reliability was excellent for lower limb lengths (ICC = 0.99), good for alignment (ICC = 0.85), comparable to low dose (ICC = 0.99 and 0.89). No correlation was found between BMI and measurements reliability in both protocols. DAP and skin dose was significantly lower (p < 0.001) in micro-dose protocol for all morphotypes (0.21 mGy vs 1.13 mGy).
Conclusion: Micro-dose BPR can be reliably used in pangonometry and allows a significant dose reduction in paediatric lower limb examinations.
Conventional radiography in juvenile idiopathic arthritis: joined recommendations from the French societies for rheumatology, radiology, paediatric radiology
Purpose: To provide guidelines concerning conventional radiography (CR), in every subtype of juvenile idiopathic arthritis (JIA) (let alone systemic JIA)
Methods and Materials: A multidisciplinary task force of 15 French rheumatologists, paediatricians, radiologists and two patients representatives was convened. Following the GRADE method for recommendations, they expressed a series of research questions. Systemic JIA was ruled out. An exhaustive literature review was performed. Articles in English describing structural damage (joint space narrowing, erosions, growth abnormalities) were considered. Several assessments were proposed, based on literature data and expert opinion when evidence-based medicine was lacking. This first draft was sent to a group of 14 independent French-speaking reviewers. It was then reconsidered by the authors, and accordingly modified. A final version was submitted for evaluation to each author and reviewer, for evaluation by a Delphi process.
Results: 72 articles were included in the literature review. Often, radiographic course was a secondary outcome. Four general statements and 28 recommendations were produced. Agreement between experts was high, ranking from 8.05 to 9.70. Grades of recommendations were mostly C and D, due to lack of power of the studies. We recommend systematic CR of hands, wrists and feet at diagnosis and follow-up when the structural threat is high. In oligoarticular JIA, CR should be performed in specific situations guided by clinical apprecation. CR is not the best imagery for axial skeletton.
Conclusion: This is the first work providing practical guidelines concerning CR in JIA - when to, and when not to, perform them.
Femoral torsion assessment with MRI in children and adolescents: should we use the bony or cartilaginous contours?
Purpose: To assess whether the use of cartilaginous contours at the femoral condyles instead of bony contours significantly changes femoral torsion measurements in children and adolescents.
Methods and Materials: Femoral torsion was measured in 32 girls (mean age 10.1 years ±2.3 standard deviation) and 42 boys (10.9 years ±2.5) by two independent readers (R1,R2). The femoral condyle angle was measured twice using once the cartilaginous and once the bony contours of the distal femur. Cartilage thickness at femoral condyles was assessed. Intraclass-correlation-coefficient (ICC) and Pearson`s correlation were used for statistical Analysis.
Results: Mean difference between cartilaginous and bony femoral torsion in girls was -1.1°±1.75 (range, -5.4° to 3.1°) for R1 and -1.64°±1.67 (-6.3° to 2.1°) for R2, in boys -1.5°±1.87(-8.4° to 1.1°) for R1 and -2.28°±1.48 (-4.3° to 9.7°) for R2. Weak-to-moderate correlations between difference of cartilaginous-versus-bony measurements and cartilage thickness (r=-0.15 to -0.55,P<0.001-0.46) or age (r=-0.33 to 0.46,P<0.001-0.006) were found for both genders. Intermethod-ICC for cartilaginous versus bony femoral torsion measurements was 0.99/0.99 for R1/R2 in girls, and 0.99/0.98 in boys.
Conclusion: There is no benefit in the use of cartilaginous condyle contours instead of bony contours for femoral torsion assessment in children and adolescents, since measurement results are interchangeable.
Human long bone development in intrauterine growth restriction: in vivo analysis of the distal femoral epimetaphysis on prenatal MR imaging
Purpose: To investigate human long bone development in fetuses with intrauterine growth restriction (IUGR) by analyzing distal femoral epimetaphyseal structures and bone morphometrics on prenatal MR imaging.
Methods and Materials: This retrospective study included 14 fetuses (mean gestational age, 26 weeks 2 days; range, 21 weeks 3 days to 33 weeks) with IUGR caused by placental insufficiency, without other brain or body abnormalities, as well as a total of 192 age-matched normal fetuses. On 1.5-T echo-planar MR images, diaphyseal and epiphyseal morphometric measurements were assessed, and, using a grading system, the cartilaginous epiphyseal and metaphyseal shape, secondary ossification, and the perichondrium were qualitatively analyzed. Student's t-testing was used to compare the morphometric measurements of IUGR fetuses with normal fetuses, and descriptive statistics were used to compare the qualitative bone characteristics.
Results: The morphometric measurements of the IUGR fetuses did not exceed the minimum normative measurements at any gestational age (diaphyseal length: p <0.0001 - 0.0053; epiphyseal length: p <0.0001 - 0.0022; epiphyseal width: p <0.0001 - 0.0032). Overall, the same grading for cartilaginous epiphyseal shape as observed in IUGR fetuses was found in 28.6% - 100% of normal fetuses, for the metaphyseal shape in 7.1% - 94.4%, for secondary ossification in 16.7% - 100%, and for the perichondrium in 12.5%- 91.7%.
Conclusion: On prenatal MR imaging, fetuses with placental-based IUGR exhibit long bone shortening, whereas their qualitative bone characteristics appear within normal limits. Consequently, the presence of qualitative bone abnormalities should include the differential diagnosis of various fetal skeletal disorders.
Purpose: Coeliac children are often subject to weight loss and lower somatic growth rate, compared to healthy children of the same age. The purpose of this study was to asses the feasibility of magnetic resonance imaging (MRI) of the hand and the wrist to assess skeletal age and growth delay.
Methods and Materials: We enrolled in our study 39 coeliac children (13 males and 26 females) affected by histological proven coeliac disease, with a chronological age ranged between 5 years and 1 month and 16 years and 4 months (mean age of 10years, +/- 3 years and 8 months standard deviation). A single MRI sequence (T13D SE, acquisition time: 1 minute 31 seconds) of the hand and wrist in coronal plane was performed of each patient to estimate the skeletal age. Patients’ data were compared with a population of normal subjects.
Results: The preliminary results showed a delay in skeletal age in children affected by coeliac disease in 85,7% of the simple study, with a delay of maturity of 0.83 years (+/- 2,2 years of SD). Only 3 children showed advance MRI skeletal age when compared to normal subjects.
Conclusion: MRI of hand/wrist to assess skeletal age may be considered as a reliable indicator of somatic growth. MRI, without radiation exposure, can be an used as a diagnostic tool in skeletal delay. It could play an important role in the follow up of coeliac children, after glutenfree diet.
Purpose: To estimate iron distribution in the bone marrow of vertebrae according to the grade of liver siderosis.
Methods and Materials: MRI T2* mapping followed by liver biopsy was performed in 43 children with beta-thalassemia (mean age - 9 years). According to the grade of liver siderosis, patients were divided into 4 groups: group 1 - without iron overload (N=8); group 2 - mild iron overload (N=8); group 3 - moderate iron overload (N=10); group 4 - severe iron overload (N=17). Quantitative estimation was conducted by Phillips Achieva 3T with T2* - mapping using Multi echo GRE pulse sequence (TR=350 ms, TE=0.9 ms, ΔTE=0.9 ms, Breath Hold).
Results: From the perspective of regression analysis, we found correlations between the values of T2* signal intensity from liver and bone marrow. 1 group - LIC (Liver iron concentration) > 2.5 ms (0.1 - 2 mg/g dry weight), VIC (Vertebrae iron concentration) > 2.5 ms, r= 0.82 (R2=0.67); 2 group - LIC of 1.5 - 2.5 ms (2-7 mg/g dw), VIC of 1.3-2.9 ms, r=0.47 (R2=0.22); 3 group - LIC of 1.0 -1.5 ms (7-15 mg/g dw), VIC of 1.0-2.8 ms, r=0.67 (R2=0.45); 4 group - LIC of 0.6-1.0 ms (>15 mg/g dw), VIC of 0.6-1.0 ms, r= 0.91 (R2=0.83).
Conclusion: VIC is an indication of severe liver iron overload in children with beta-thalassemia.
Diffusion-weighted MRI and FDG-PET in children with mediastinal lymphoma: does the apparent diffusion coefficient (ADC) discriminate between benign and malignant masses?
Purpose: To intraindividually evaluate the role of diffusion weighted MRI (DWI) with ADC measurement as a marker of malignancy in children with mediastinal lymphoma in comparison to standardized uptake values (SUV) calculated by positron emission tomography computed tomography (PET-CT).
Methods and Materials: DWI-MRI and PET-CT were performed in 16 consecutive patients with histologically proven Hodgkin’s and Non-Hodgkin’s lymphoma before initiation of chemotherapy, comprising a total amount of 104 malignant nodes. DWI was performed at 3T with the following imaging parameters: TR/TE 2000/66ms; FOV 425mm; slice thickness 4mm; b-values 0, 25, 50, 75, 150, 500 and 900. By placing a region of interest (ROI) encovering the entire tumor manifestation, the minimum (ADCmin), mean (ADCmean) and maximum (ADCmax) ADC as well as the mean and maximum SUV (SUVmean and SUVmax) were determined by two independent radiologists. The results of DWI and PET-CT were statistically compared on a per-node base applying Pearson’s correlation coefficient.
Results: The comparison of the ADCmin and SUVmax indicated a statistically significant inverse correlation (r=0.91; p=0.02). In contrast, no correlation was found between ADCmean and SUVmean (r=0.37; p=0.51). Higher tracer uptake at PET-CT and lower ADC were determined in Hodgkin’s lymphoma compared to Non-Hodgkin’s lymphoma.
Conclusion: The minimum ADC values demonstrate a higher tumor metabolism, as confirmed by SUV measurements, and allows the discrimination of benign and malignant mediastinal masses. In pediatric patients, DWI with ADC measurement should be considered as a powerful, radiation-free complementary tool in the diagnostic workup of mediastinal lymphoma.
Vessel wall changes after radiochemotherapy in former paediatric medulloblastoma patients: a high-resolution MRI
Purpose: High-resolution MRI (HR-MRI), including vessel wall imaging (VWI), is an emerging tool for evaluating intracranial vessel disease. Going along with the improved survival of medulloblastoma (MB) patients, an increasing number of long-term MB survivors experiences cerebrovascular late sequelae of the applied radiochemotherapy (RCT), including early occurrence of atherosclerotic lesions. This study evaluates radiation-induced intracranial vascular changes, imaged through HR-MRI.
Methods and Materials: In this prospective study, 22 former MB patients were enrolled (range 10-53 years, mean age 25.8 years). The internal carotid artery (ICA) and the basilar artery (BA) were analysed. Following MR sequences were performed: precontrast 3D TOF-MRA, precontrast 2D T1- and 2D T2-VWI sequences and postcontrast 2D T1-VWI sequences. Vessel wall thickening, postcontrast enhancement (CE) and luminal narrowing were analysed in every image.
Results: In 7 (31%) and 5 (22%) out of 22 patients vessel wall alterations in the right and left ICA, respectively, were found. Alterations in the BA vessel wall were found in 13 (59%) patients. In total, 59% of the patients presented vessel wall changes. TOF-MRA did not reveal any alteration of the ICA or BA, respectively.
Conclusion: Cerebrovascular changes after RCT gain importance, as treatment and overall survival for MB patients is improving. In this study, vessel wall alterations were imaged with high-resolution MRI. In more than 50% vessel wall alterations were identified. Further studies are needed to image the progression of sequelae after RCT and to determine the time for preventive treatment, regarding vessel stenosis.
MR imaging of post-treatment local bone marrow alterations in paediatric soft tissue sarcomas of the extremities
Purpose: To retrospectively assess, by MRI, post-treatment local bone marrow abnormalities (BMA) occurring in pediatric patients affected by soft tissue sarcomas of the extremities (eSTS).
Methods and Materials: Pediatric patients with histologically proven eSTS, a follow-up of at least two years from diagnosis, and both pre- and post-treatment MRI scans of the affected limb were included.Two radiologists independently reviewed for BMA all available restaging examinations.Size, pattern, contrast-enhancement and site of involvement, as long as the risk (10 points-scale) for each BMA to be a metastasis (BMM), were assessed;intraclass correlation coefficient (ICC) and 95% confidence interval were calculated.
Results: Twenty-nine patients (age-range 1mo-20 yrs) met the inclusion criteria.Histology showed 12 alveolar and 4 embrional rhabdomyosarcomas, 3 fibromyxoid and Ewing sarcoma, 2 synovial sarcomas;angiosarcoma, extraskeletal osteosarcoma, epitelioid, fibrosarcoma and liposarcoma, in one patient each.Two patients were treated only with surgical excision, 2 only with chemotherapy, 6 only with radiotherapy and 19 with radio and chemotherapy.Seventeen BMA were diagnosed in nine patients.Most of the BMA were nodular or patchy (n=5) and smaller than 3 cm (n=11);all, except one, showed contrast-enhancement.The mean rate for BMM’s risk was 2.12, with a high ICC (0.890;95%CI 0.721-0.959).Only one BMA (later on, histologically proven metastases in a patient with known wide-spread disease) showed a significant risk of 7. At the latest available follow-up, all other BMA solved.
Conclusion: To optimally assist the clinicians and avoid the risk of overrating,radiologists should carefully interpret BMAs occurring at local restaging in children treated for eSTS, which rarely represent malignant dissemination.