Intramuscular myxomas appear as well-demarcated, homogenous and hypodense ovoid lesions. The soft tissue mass attenuation is higher than that of water and ...×ArticlesLogInCasesSignUpCoursesQuizBlogDonateAbout×MenuSearchADVERTISEMENT:Radiopaediaisfreethankstooursupportersandadvertisers.BecomeaGoldSupporterandseenoads.ArticlesCasesCoursesLogInLoginSignup{"url":"/signup-modal-props.json?lang=us\u0026email="}ArticlesCasesCoursesQuizAboutBlogGoad-freeSearchIntramuscularmyxomaDrMattAdams◉andDrYurangaWeerakkody◉etal.Intramuscularmyxomasareararebenigntypeofsofttissuemyxomathatismesenchymalinorigin.Onthispage:Article:EpidemiologyClinicalpresentationPathologyRadiographicfeaturesTreatmentandprognosisDifferentialdiagnosisSeealsoReferencesImages:CasesandfiguresImagingdifferentialdiagnosisEpidemiologyIncidenceisreportedtobe1in1000000andmostfrequentlydiagnosedinfemales(~57%)patientsbetween40-70years 1.ClinicalpresentationThetypicalpresentationisthatofaslowlyenlargingmass(es)in64%ofpatients1.Thelesionsareadeeplyseatedmassconfinedtoskeletalmuscleandwithoutmalignantpotential.Apainfulmasswillbepresentin~55%ofpatients1,3. PathologyMyxomashavebeenreportedtorangeinsizefrom1-17cm1,2.Intramuscularmyxomascanbesolitaryormultiple,whenmultiplemyxomasarepresenttheyareassociatedwithmonostoticorpolyostoticfibrousdysplasia,knownasMazabraudsyndrome 1,3-5.LocationIntramuscularmyxomascanbelocatedinanyskeletalmusclegrouphowevermostcommonlyoccurinthequadriceps(65%),hipadductors(~35%),gluteusmuscles(~20%),gastrocnemiusandupperarm1,3.Whenoccurringinconjunctionwithfibrousdysplasia theyaretypicallylocatedinthevicinityofthebonelesions.Bothfibrousdysplasiaandintramuscularmyxomasmostcommonlyaffectthepelvicgirdleandlowerlimbs(75%).Theupperlimbsareaffectedinlessthanaquarterofreportedcases.Microscopicappearancelesionsaregenerallyhypocellularandhypovascularalthoughareasofincreasedvascularityandcellularitymaybepresent1thereareloosereticulinfiberswithinanabundantmyxoidstroma1,6thecellshaveastellateshapewithsmallhy