The Mellado-Bencardino classification of Morel-Lavallée lesions is based on shape, signal and enhancement characteristics, and the presence or absence of a capsule 1:
- type I: laminar-shaped and seroma-like with increased T2 signal
- type II: oval-shape that resembles a subacute hematoma with increased T1 and T2 signal; thick capsule and variable enhancement
- type III: oval shaped resembling a chronic organizing hematoma; thick capsule and internal/peripheral enhancement
- type IV: linear; looks like a closed laceration with hypointense T1 signal and hyperintense T2 signal; no capsule and variable enhancement
- type V: pseudonodular with a round shape, variable T1 and T2 signal, a thin or thick capsule, internal/peripheral enhancement
- type VI: infected with variable T1 and T2 signal; variable sinus tract formation, a thick capsule, and internal/peripheral enhancement