Reason: any change in pelvic mass? History: girl with NF1 and known pelvic mass Metal susceptibility artifact from the patient's lumbar spine fixation device limits evaluation of the surrounding area. Again seen is a reference enhancing mass within the pelvis that extends slightly through the left sciatic notch situated along the anterior aspect of the left piriformis muscle. It is again noted to abut the posterior aspect of the left acetabulum and anterior aspect of the left sacral wing and lies posterior to the left iliac vasculature. The mass measures 5.5 x 5.3 cm, previously 4.5 x 4.3 cm (image 23; series 3), slightly increased in size when compared to the prior examination. There is a small amount of fluid within the hips bilaterally, right greater than left, which is not necessarily of any clinical significance. The remainder of the imaged musculature of the pelvis is unremarkable. There are tiny foci of cutaneous nodular enhancement likely representing cutaneous neurofibromas, unchanged. Although this examination was not protocoled for detailed evaluation of the pelvic viscera, no additional abnormality is identified. Note is made of multiple bilateral ovarian follicles.
Slight interval increase in the reference left sacrosciatic notch mass with measurements provided above. While a malignant peripheral nerve sheath tumor cannot be completely excluded, this likely represents a benign neurofibroma.