Fig. 12
From: Pelvic heterotopic ossification: when CT comes to the aid of MR imaging
A 30-year-old male patient affected by posterior element incomplete fusion (spina bifida occulta). a On first CT axial scan a bulky immature ossification is revealed adjacent to the left iliac wing. This HO was not comprised into the MR acquisition volume that was lower centred because of the clinical relevancy of a posterior ischiofemural abscess. b A 10-month follow-up CT scan shows the lesion appears to be fragmented and partially resorbed. A marked soft tissue swelling is now visible caused by an underlying infectious process