Granuloma anulare
Pseudotumoural
soft tissue lesions of the foot and ankle: a pictorial review. Granuloma annulare (combined cutaneous-subcutaneous presentation). A 14-year-old patient presenting with a round, erythematous skin lesion at the dorsum of the foot (a), with mild associated swelling. MR images: short axis T1-WI (b) and fat-suppressed T2-WI (c); short-axis (d) and sagittal (e) fat-suppressed contrast-enhanced T1-WI. Disc-like, ill-defined subcutaneous lesion at the dorsum of the foot. The lesion is iso-intense to muscle on T1-WI, is of high SI on T2-WI and demonstrates marked, slightly heterogeneous contrast enhancement
Granuloma annulare is a benign idiopathic inflammatory disorder of the dermis, characterized by formation of dermal papules in young children.
Clinical presentation
Granuloma annulare most commonly seen in kids between 2-12 years old and usually it occurs in extremities. One typical location is pretibial when the lesion is subcutaneous. It has various clinical presentations:
- three cutaneous forms
- erythematous
- perforating
- generalized
- one subcutaneous form: presenting as a soft tissue mass - subcutaneous granuloma annulare
Radiographic features
Plain radiograph
These have very little value. The only manifestation is non-specific increased density in the subcutaneous compartment without involvement of bone involvement or mineralization.
Ultrasound
Shows ill-defined solid mass that is hypoechoic to surrounding fat. It excludes a vascular of cystic lesion.
MRI
- T1: ill-defined subcutaneous mass, isointense to muscle
- T2: slightly hypointense signal intensity compared with fat, but may also show heterogeneous hyperintense signal
- T1 C+: diffuse enhancement can be seen
Siehe auch:
Assoziationen und Differentialdiagnosen zu Granuloma anulare: