Proton magnetic resonance chemical shift imaging (H-1 CSI)-directed stereotactic biopsy

Introduction. To add metabolic information during stereotactic biopsy targe t selection, the authors adopted proton chemical shift imaging (H-1 CSI)-di rected stereotactic biopsy. Currently, proton single voxel spectroscopy (SV S) technique has been reported in stereotactic biopsy. We performed H-1 CSI in combination with a stereotactic headframe and selected targets accordin g to local metabolic information, and evaluated the pathological results. Patients and Method. The H-1 CSI-directed stereotactic biopsy was performed in four patients. H-1 CSI and conventional Gd-enhancement stereotactic MRI were performed simultaneously after the fitting of a stereotactic frame. A fter reconstructing the metabolic maps of N-acetylaspartate (NAA)/phosphocr eatine (Cr), phosphocholine (Cho)/Cr, and Lactate/Cr ratios, focal areas of increased Cho/Cr ratio and Lac/Cr ratios were selected as target sites in the stereotactic MR images. Result. H-1 CSI is possible with the stereotactic headframe in place. No di fficulty was experienced performing H-1 CSI or making a diagnosis. Patholog ical samples taken from areas of increased Cho/Cr ratios and decreased NAA/ Cr ratios provided information upon increased cellularity, mitoses and cell ular atypism, and facilitated diagnosis. Pathological samples taken from ar eas of increased Lac/Cr ratio showed predominant feature of necrosis. Conclusion. H-1 CSI was feasible with the stereotactic headframe in place. The final pathological results obtained were concordant with the local meta bolic information from H-1 CSI. We believe that H-1 CSI-directed stereotati c biopsy has the potential to significantly improve the accuracy of stereot actic biopsy targeting.