UMEM Educational Pearls

Title: Necrotizing Fasciitis on Ultrasound

Category: Ultrasound

Keywords: soft tissue; point of care ultrasound (PubMed Search)

Posted: 4/20/2026 by Alexis Salerno Rubeling, MD
Click here to contact Alexis Salerno Rubeling, MD

Sonographic findings suggestive of necrotizing fasciitis include: 

  • Thickening of the deep fascia 
  • Diffuse thickening of the overlying fatty tissue 
  • At least a 4 mm thick fluid layer along the deep fascia 
  • Dirty Shadow if gas is present

Remember the mnemonic: STAFF (subcutaneous thickening, air, and fascial fluid) 

References

Castleberg E, Jenson N, Dinh VA. Diagnosis of necrotizing fascititis with bedside ultrasound: the STAFF exam. West J Emerg Med. 2014;15(1):111-3.