Comparison of whole-body muscle imaging findings between GNE myopathy and other young adult-onset hereditary myopathies

Figures

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  Fig 1. Axial view of whole-body muscle magnetic resonance images for evaluating pathological changes in different sequences. In the five grades of fatty tissue replacement on T1-weighted images (A-C), grade 0 was considered the normal appearance (A). Pathological changes of grade 1 (mild condition with trace amounts of fat signal (<25%)) were noted in the bilateral vastus medialis (VM) and vastus lateralis (VL) (C), grade 2 (moderate condition with initial confluence observed in <50% of muscle) in the right biceps femoris (BF) long head and bilateral vastus intermedialis (Vi) (C), grade 3 (severe condition with confluence observed in >50% of muscle) in sartorius (Sart), gracilis (Grac), semimembranosus (Semm), semitendinosus (Semt) both sides and left BF long head (C), and grade 4 (end-stage disease with fat signals covering the entire muscle) in the bilateral gastrocnemius medial head (GTM) (B). STIR images (D-E) revealed the presence of muscle edema (star marks) (E) compared with the absence of muscle edema (D). Proton-density fat fractions (PDFF) evaluated on DIXON imaging (F-G) revealed a mild degree of fatty tissue replacement in bilateral masseter muscles, with PDFFs of 7.6% and…

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  Fig 2. Heat map of the five grades of fatty tissue replacement on T1-weighted imaging of the five patients with GNE myopathy and the comparison of the fatty tissue replacement grades and PDFF between the GNE and non-GNE groups. The fatty tissue replacement severity was categorized into five grades, ranging from 0 (normal) to 4 (the most severe). Data are presented as medians and interquartile ranges. Abbreviations: TMP; temporalis, MSS; masseter, MPt; medial pterygoid, LPt lateral pterygoid, Tong; tongue, SCM; sternocleidomastoid, Cext; cervical extensor, Lcollis; longus collis, Ltsm; latissimus dorsi, Trpz; trapezius, Delt; deltoid, SSp; supraspinatus, Isp; infraspinatus, SScp; subscapularis, Pect; pectoralis minor and major, SA; serratus anterior, BC; biceps, TC; triceps, Ant; anterior compartment of the forearm, Mob; mobile-wad muscles of the forearm, Post; posterior compartment of the forearm, ICM; intercostal muscles, T.ext; thoracic extensor, L.ext; lumbar extensor, Psoas; psoas muscle, Abd; abdominal belt muscles, GMax; gluteus maximus, Gmed; gluteus medius, Gmin; gluteus minimus, AddM; adductor magnus, AddL; adductor longus, Pec; pectineus, RF; rectus femoris, VL; vastus…

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  Fig 3. Heat map of the presence of muscle edema on STRI imaging in the five patients with GNE myopathy and the comparison of the prevalence of muscle edema between the GNE and non-GNE groups. Edematous muscles are indicated in red. Data are presented as medians and interquartile ranges. The same abbreviations in Fig 2 were used.