Freehand-SPECT with 99mTc-HDP as tool to guide percutaneous biopsy of skeletal lesions detected on bone scintigraphy

Abstract

Purpose: To assess the feasibility of using freehand Single Photon Emission Computed Tomography (freehandSPECT) for the identification of technetium-99m-hydroxydiphosphonate (^99mTc-HDP) positive bone lesions and to evaluate the possibility of using these imaging data-sets for augmented- and virtual-reality based navigation approaches.

Material and methods: In 20 consecutive patients referred for scintigraphy with ^99mTc-HDP, 21 three-dimensional freehandSPECT-images were generated using a handheld gamma camera. Concordance of the two different data sets was ranked. Furthermore, feasibility of segmenting the hotspot of tracer accumulation for navigation purposes was assessed.

Results: In 86% of the cases freehandSPECT images showed good concordance with the corresponding part of the scintigraphic images. In lesions with a signal to background ratio (SBR) >1.36, freehandSPECT provided an automatically segmented reference point for navigation purposes. In 14% of the cases (average SBR 1.82, range 1.0-3.4) freehandSPECT images showed intermediate concordance due to difficult anatomical area or negative bone scintigraphy and could not be used as navigation targets.

Conclusion: In this pilot study, in 86% of the cases freehandSPECT demonstrated good concordance with traditional scintigraphy. A lesion with a SBR of 1.36 or more was suitable for navigation. These high-quality freehandSPECT images supported the future exploration navigation strategies, e.g. guided needle biopsies.

Keywords: Biopsia; Biopsy; Bone; Hueso; Imagen molecular; Molecular imaging; Navegación; Navigation; SPECT.