Importance: The role of cytoreductive nephrectomy in patients with metastatic renal cancer in the era of targeted therapy is uncertain. Data on targeted therapy prior to nephrectomy is lacking.Objective: To establish the safety and efficacy of upfront pazopanib prior to cytoreductive nephrectomy in previously untreated metastatic clear cell renal cancer.

PurposeTo propose a novel segmentation framework that is dedicated to the follow‐up of fat infiltration in individual muscles of patients with neuromuscular disorders.MethodsWe designed a semi‐automatic segmentation pipeline of individual leg muscles in MR images based on automatic propagation through nonlinear registrations of initial delineation in a minimal number of MR slices. This approach has been validated for the segmentation of individual muscles from MRI data sets, acquired over a 10‐month period, from thighs and legs in 10 patients with muscular dystrophy. The robustness of the framework was evaluated using conventional metrics related to muscle volume and clinical metrics related to fat infiltration.ResultsHigh accuracy of the semi‐automatic segmentation (mean Dice similarity coefficient higher than 0.89) was reported. The provided method has excellent reliability regarding the reproducibility of the fat fraction estimation, with an average intraclass correlation coefficient score of 0.99. Furthermore, the present segmentation framework was determined to be more reliable than the intra‐expert performance, which had an average intraclass correlation coefficient of 0.93.ConclusionThe proposed framework of segmentation can successfully provide an effective and reliable tool for accurate follow‐up of any MRI biomarkers in neuromuscular disorders. This method could assist the quantitative assessment of muscular changes occurring in such diseases.

BackgroundDeep learning methods have been shown to be useful for segmentation of lower limb muscle MRIs of healthy subjects but, have not been sufficiently evaluated on neuromuscular disease (NDM) patients.PurposeEvaluate the influence of fat infiltration on convolutional neural network (CNN) segmentation of MRIs from NMD patients.Study TypeRetrospective study.SubjectsData were collected from a hospital database of 67 patients with NMDs and 14 controls (age: 53 ± 17 years, sex: 48 M, 33 F). Ten individual muscles were segmented from the thigh and six from the calf (20 slices, 200 cm section).Field Strength/SequenceA 1.5 T. Sequences: 2D T1‐weighted fast spin echo. Fat fraction (FF): three‐point Dixon 3D GRE, magnetization transfer ratio (MTR): 3D MT‐prepared GRE, T2: 2D multispin‐echo sequence.AssessmentU‐Net 2D, U‐Net 3D, TransUNet, and HRNet were trained to segment thigh and leg muscles (101/11 and 95/11 training/validation images, 10‐fold cross‐validation). Automatic and manual segmentations were compared based on geometric criteria (Dice coefficient [DSC], outlier rate, absence rate) and reliability of measured MRI quantities (FF, MTR, T2, volume).Statistical TestsBland–Altman plots were chosen to describe agreement between manual vs. automatic estimated FF, MTR, T2 and volume. Comparisons were made between muscle populations with an FF greater than 20% (G20+) and lower than 20% (G20−).ResultsThe CNNs achieved equivalent results, yet only HRNet recognized every muscle in the database, with a DSC of 0.91 ± 0.08, and measurement biases reaching −0.32% ± 0.92% for FF, 0.19 ± 0.77 for MTR, −0.55 ± 1.95 msec for T2, and − 0.38 ± 3.67 cm3 for volume. The performances of HRNet, between G20− and G20+ decreased significantly.Data ConclusionHRNet was the most appropriate network, as it did not omit any muscle. The accuracy obtained shows that CNNs could provide fully automated methods for studying NMDs. However, the accuracy of the methods may be degraded on the most infiltrated muscles (>20%).Evidence Level4.Technical EfficacyStage 1.

No abstract

Facioscapulohumeral dystrophy is the third genetic myopathy. Given that no therapeutic strategy has proved to be successful, rehabilitation has been considered as an interesting alternative. The aim of this study was to quantitatively evaluate the effects of a personalized rehabilitation strategy using MRI by tracking fat fraction (FF) and contractile volume (CV) over time. The lower limb was scanned before and after a rehabilitation program. FF and CV remained stable over the training period. Clinical parameters evolved positively. FF and CV were correlated to isokinetic strength thereby indicating that both metrics could be considered as biomarkers of the pathology progression.

Background:Fibrocartilaginous enthesis is composed of different histological zones which are commonly referred to the tendon distal extremity (a lamellar tissue with a low cell density, collagen and connective tissue), the fibrocartilaginous zone (with chondrocytes), a progressively mineralized zone and the bone. The MRI visualization of the water content of entheses is challenging given the very short relation time so that entheses has been very poorly assessed using MRI (1).Objectives:The main objective of the study was to assess the structural elements of the knee enthesis based on the quantitative T2* measurements using Ultra High Field (UHF) MRI.Methods:Twelve healthy subjects without any osteoarticular pathology were included in the study after they provided their informed consent. 3D gradient echo sequence with a 4.3 ms echo time and T2* mapping were performed. The lateral internal, external and crossed ligaments, patellar and quadricipital tendons were assessed. T2* measurements were performed specifically on the quadricipital tendon.Results:The quadricipital tendon and the bone trabeculation could be visualized on the UHF MR image. The T2* mapping analysis illustrated a large value (16.4 ± 4 ms) for the subchondral bone and much lower values for the trabecular bone (11 ± 4.5 ms) and the different zones of the keen entheses (7.7 ± 1.9 ms).Conclusion:Based on T2* measurements performed using UHF MRI, the different structural elements of the knee entheses were distinguished. This quantitative stratification could be used to assess changes in pathological conditions such as SpA and trauma.References:[1]Benjamin M, Bydder GM. Magnetic resonance imaging of entheses using ultrashort TE (UTE) pulse sequences. Journal of magnetic resonance imaging: JMRI. 2007;25(2):381-9.Disclosure of Interests:None declared

No abstract

No abstract