The application of 99Tcm-RBC scintigraphy in the diagnosis of orbital cavernous hemangioma

Objective: The purpose of this study was to evaluate the clinical value of 99Tcm-RBC scintigraphy in the diagnosis of orbital cavernous hemangioma (OCH). Methods: Forty-one patients with pathologically confirmed orbital mass, of which 10 were OCH, underwent 99Tcm-RBC scintigraphy in this study. The scanning procedure included an initial perfusion phase, followed by an early and a delayed blood pool phase. All patients underwent ultrasonography and CT, and 15 patients also underwent MRI. SPSS 11.5 was used to analyse the data. Results: All 10 OCH patients had no abnormal findings on radionuclide angiographic images and early blood pool phase, but increased activity was found during delayed blood pool phase. All the other non-OCH orbital tumors did not have this tracer pattern. The radioactivity ratios of the lump to non-lump (L/N) were 2.96 ± 0.05 and 1.14 ± 0.25, respectively, which had a statistically significant difference (t=15.18, P<0.001). When 9 of 10 OCH patients were dignosed correctly with 1 false positive case by ultrasoud, both CT and MRI could not provide definitive diagnosis. Conclusions: 99Tcm- RBC scintigraphy is a reliable and useful procedure for the diagnosis of OCH. It may be considered as one of the routine clinical screening tools for the diagnosis of OCH and as a complement investigation to ultrasonography and CT. (authors)