Integrating both MRI findings and LRINEC scoring produced values of 77%, 84%, 82%, and 79%, respectively. They concluded that MRI findings improved the overall sensitivity of diagnosing NF. There are varying reports regarding the amount of fascial enhancement present based on the stage of necrosis [49,52]. Similar to CT, the assessment of fascial enhancement is controversial. Based upon studies in the MRI literature from >20 years ago, NF fascial enhancement patterns following IV contrast administration are variable with nonenhancement, mixed, and enhancement patterns all reported in the medical literature [2,58]. The presence of fascial enhancement is attributed to increased capillary permeability and IV contrast extravasation. In contrast, the absence of fascial enhancement is attributed to necrosis and microvascular occlusion [2,49,52,58]. In the later stages of NF, focal or diffuse nonenhancement of the fascia may be seen because of necrosis, which can be helpful to differentiate from non-NF [50,52,57]. In general, contrast-enhanced MRI aids in the identification of abscess and areas of necrosis, extent of infection, and delineation of vascular involvement, which can be beneficial in NF [2,49,52]. However, noncontrast MRI is still an important examination with the highest reported sensitivities to detect soft tissue findings of fascial edema/fluid signal and can detect the known imaging findings of NF to include deep fascial/intermuscular edema, soft tissue gas, and fluid collections [2,49,50,52,56,57]. US Area of Interest US findings of NF include soft tissue gas, subcutaneous fat edema, and irregular thickening and fluid along superficial and deep fascial planes [52,57,59,60]. A unique benefit to US is the ability to compare the contralateral extremity or other regions of normal tissue.
Suspected Osteomyelitis Septic Arthritis or Soft Tissue Infection Excluding Spine and Diabetic Foot PCAs. Integrating both MRI findings and LRINEC scoring produced values of 77%, 84%, 82%, and 79%, respectively. They concluded that MRI findings improved the overall sensitivity of diagnosing NF. There are varying reports regarding the amount of fascial enhancement present based on the stage of necrosis [49,52]. Similar to CT, the assessment of fascial enhancement is controversial. Based upon studies in the MRI literature from >20 years ago, NF fascial enhancement patterns following IV contrast administration are variable with nonenhancement, mixed, and enhancement patterns all reported in the medical literature [2,58]. The presence of fascial enhancement is attributed to increased capillary permeability and IV contrast extravasation. In contrast, the absence of fascial enhancement is attributed to necrosis and microvascular occlusion [2,49,52,58]. In the later stages of NF, focal or diffuse nonenhancement of the fascia may be seen because of necrosis, which can be helpful to differentiate from non-NF [50,52,57]. In general, contrast-enhanced MRI aids in the identification of abscess and areas of necrosis, extent of infection, and delineation of vascular involvement, which can be beneficial in NF [2,49,52]. However, noncontrast MRI is still an important examination with the highest reported sensitivities to detect soft tissue findings of fascial edema/fluid signal and can detect the known imaging findings of NF to include deep fascial/intermuscular edema, soft tissue gas, and fluid collections [2,49,50,52,56,57]. US Area of Interest US findings of NF include soft tissue gas, subcutaneous fat edema, and irregular thickening and fluid along superficial and deep fascial planes [52,57,59,60]. A unique benefit to US is the ability to compare the contralateral extremity or other regions of normal tissue.