E1497. Doctor, Why is This Muscle So Big? Review of Pathologies That Cause Muscle Enlargement in the Head and Neck
Authors
Mussanna Ahmed;
SUNY Downstate Health Sciences University
Mossum Sawhney;
SUNY Downstate Health Sciences University
Zeshan Chaudhry;
SUNY Downstate Health Sciences University
Deborah Reede;
SUNY Downstate Health Sciences University
Wendy Smoker;
University of Iowa Hospitals & Clinics
Background
Head and neck anatomy is complex, with a spectrum of disease entities that pose diagnostic dilemmas for even the most experienced radiologists. The knowledge obtained from viewing this exhibit will enable the user to develop a systematic approach for evaluating pathologies that cause enlargement of head and neck muscles. We will review the clinical and imaging findings encountered in infectious/inflammatory, neoplastic, traumatic, congenital/developmental, and vascular processes involving the head and neck muscles.
Educational Goals / Teaching Points
The goals of this exhibit are to review pathologies that cause enlargement of muscles in the head and neck; demonstrate the imaging appearance of common and uncommon pathologies that affect these muscles; and learn an image-based algorithm that aids in the development of an appropriate differential diagnosis.
Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
Cases are categorized based on the imaging appearance as follows. Muscle enlargement with normal CT/MR appearance (masseter and levator scapulae muscle hypertrophy); muscle enlargement with enhancement (myositis); and muscle enlargement with abnormal attenuation/signal. Predominantly fat attenuation/signal includes intramuscular lipoma, lipoblastoma; fluid attenuation/signal (with or without enhancement) includes venolymphatic malformation, intramuscular abscess, thyroglossal duct cyst; mixed attenuation/ signal includes sarcomas, intramuscular hematoma, B cell lymphoma, schwannoma, fibromatosis coli; increased attenuation on noncontrast-enhanced CT isintramuscular hematoma; and calcification includes myositis ossificans, hemangiomas, venous malformations.
Conclusion
Familiarity with the clinical and imaging findings of pathologies involving head and neck musculature facilitates the development of an appropriate image-based differential diagnoses.