Imaging of intramuscular abscesses: A pictorial view of four cases

Abstract

Intramuscular abscesses are pus-filled walled-off collections, often unnoticed clinically. Medical imaging aids diagnosis and guided interventions. This report presents four cases of intra-muscular abscesses detected using imaging. Case 01: Left iliopsoas abscess-A 55-year-old woman presented with left lower abdominal associated with fever. The ultrasound scan of the abdomen showed a small fluid collection with internal echogenic debris in the left-sided pelvis. Contrast-enhanced CT (CECT) revealed a localised fluid collection with an enhancing wall in the iliopsoas muscle suggestive of a muscle abscess. Case 02: Left erector spinae abscess A 48-year-old woman presented with fever, left-side chest wall swelling, and pain. Ultrasonography showed a localised fluid collection on the left chest wall. Contrast-enhanced MRI demonstrated a localised abscess with internal separations in the left erector spinae muscle. Case 03: Diffuse pyomyositis with developing abscess in obturator externus and quadratus femoris muscles-48-year-old man presented with fever and painful right gluteal and back thigh regions. MRI images showed diffuse hyperintensity in T2W and STIR images concerning the obturator externus and quadratus femoris muscles, suggesting diffuse pyomyositis. In addition, multiple hyperintense pockets with diffusion restriction within that muscle, suggest a developing abscess. Case 04: Multiple abscesses and gas locules in the right sternocleidomastoid muscle. A 62-year-old woman presented with fever and right-side neck swelling. Ultrasonography demonstrated significant soft tissue oedema and fluid collections with gas shadows. CECT showed multiple abscesses and inflammation in the right sternocleidomastoid muscle and adjacent soft tissues. In addition, gas locales were noted within the collections, suggesting the aetiology of gas-forming organisms. Ultrasonography plays a crucial role in early diagnosis, while CECT or MR are essential for characterizing intramuscular abscesses. Diffusion-weighted imaging is significant for confirming the presence of an abscess. Consequently, these imaging techniques aid in making treatment decisions and guiding interventions, ultimately leading to improved patient outcomes.