C.E. Erasmus,L. van Haaften,Lenie van den Engel-Hoek,M. Lagarde,M. van Gerven,R.J.C. Admiraal, Mastication Problems and Dysphagia In 4 Patients with Treacher Collins Syndrome Due to Affected Orofacial Muscles Radiology and Medical Diagnostic Imaging 2019 2613-7836 http://dx.doi.org/10.31487/j.RDI.2019.03.09 https://www.sciencerepository.org/mastication-problems-and-dysphagia-in-4-patients-with-treacher-collins-syndrome-due-to-affected-orofacial-muscles_RDI-2019-3-109 Abstract: Treacher Collins syndrome (TCS) is a rare congenital disorder of craniofacial development affecting 1 in 50 000 live births. The spectrum of the clinical features is wide ranging from mild to severe anatomical deviances, affecting breathing, mastication, swallowing, facial expression, hearing and speech. The aim of this study was to describe the experienced feeding and swallowing problems and to study the related orofacial muscles in four patients with Treacher Collins Syndrome (TCS), in order to increase important knowledge concerning mastication and swallowing problems in children with TCS. Four children with TCS were evaluated with a clinical feeding and swallowing assessment. In addition, quantitative muscle ultrasound of orofacial muscles was performed. The mastication problems and dysphagia are due to a range of problems. Orofacial muscles were hypoplastic with a deviant structure influencing strength. We recommend a regularly assessment with special attention to mastication, intake and growth. Training (maintain chewing) and compensation (adequate intake) should be advised.Keywords: Treacher collins syndrome, dysphagia, mastication problems, muscle ultrasound, orofacial muscles