Comparison of mri and somatostatin receptor scintigraphy (SRS) in postsurgical follow-up of meningioma

In this study SRS and MRI were compared in postsurgical follow-up of meningioma. Prior to and 2-3 months after surgery 27 patients received standard MRT. as well as SRS after i.v. injection of 200 MBq In-lll-octreotide. Planar whole-body images were obtained at 10 min, 1, 4, and 24 hrs. p.i., and SPECT was performed at 4 and 24 hrs p.i. Final diagnosis was proven histologically in all patients. Prior to surgery MRI showed focal contrast enhancement in all patients, and SRS revealed focal accumulation of In-lll-octreotide in 27 patients. Thus, preoperative MRI and SRS yielded comparable results. After surgery MRI showed diffuse contrast enhancement in all patients. Thus, MRI did not allow to differentiate between tumor tissue and unspecific hyperperfusion. In contrast, SRS revealed focal accumulation of In-lll-octreotide in 16 out of 27 patients indicating tumor remnants or relapse of meningioma. This resulted either in an operative revision or in more frequent follow-up examinations. In 11 out of 27 patients SRS was negative confirming total resection of meningioma. SRS has a significant impact in postsurgical follow-up in patients with meningioma.