Purpose: The aim of this study is to determine if contrast enhanced (CE) sampling perfection with application-optimized contrasts using different flip-angle evolutions (SPACE) images can provide clearer pituitary adenoma margin than conventional CE T1-weighted spin echo (T1-SE) sequence for cavernous sinus (CS) invasion evaluation.
Methods: 21 healthy volunteers were preformed with SPACE scans before and after administration of gadopentetate dimeglumine at different time points (1, 7 and 13 min). Signal intensity (SI) of regions of interest was plotted in SI/time curves for bilateral CS, pituitary and temporal lobe. 35 patients with pituitary adenoma (≥1 cm) were performed CE T1-SE and CE SPACE scans. Two observers made the visual assessment of the tumor margin delineation and CS invasion evaluation on both SPACE and T1-SE images. Surgical findings were compared with the invasion assessment results.
Results: At 1, 7 and 13 min after enhancement, SI of left CS increased 6.7, 9.5 and 11.2% respectively compared with unenhanced images (all p < 0.05). Right CS increased 7.2, 9.3 and 11.3% (all p < 0.05%). Within pituitary, a decline (6.3%, p < 0.05) of SI was measured at 1 min after enhancement. CE SPACE performed superior to those of CE T1-SE sequence in visual assessment of tumor edge (assessment score, 1.66 ± 0.42 vs. 1.23 ± 0.65, p < 0.05), as well as the specificity (86.8 vs. 66.0%, p < 0.05) and accuracy (85.7 vs. 68.6%, p < 0.05) for CS invasion evaluation.
Conclusion: CE SPACE could provide better contrast of pituitary adenoma with surrounding CS and clear demonstration of tumor edge for CS invasion evaluation than conventional CE T1-SE sequence.