Spontaneous soft tissue haematoma in a patient with neurofibromatosis type 1
Presentation
Spontaneous painful swelling of the posterior aspect of the right upper thigh two weeks prior. No history of trauma or anticoagulant therapy.
Patient Data
Large lobulated mass centred on the right gluteus maximus muscle with subaponeurotic downward extension, eliciting a high signal on T1, low signal on T2, STIR and GE with surrounding inflammatory changes of low signal on T1, high signal on T2 and STIR with enhancement on post-contrast sequences.
Numerous bilateral cutaneous and subcutaneous nodules of low signal on T, high signal on T2 and STIR with enhancement suggestive of neurofibromas.
Case Discussion
The clinical presentation and the MRI features are most consistent with a spontaneous soft tissue haematoma with surrounding inflammatory changes in a patient known for neurofibromatosis type 1.
Spontaneous soft tissue haematomas are rarely described in the literature and usually due to the fragile nature of the vascular tree secondary to arterial dysplasia or vascular invasion of the vessel wall by the neurofibromas 1,2.