Assessment of HN malignancies with in vivo s-v 1H-MR

Objectives: To assess the diagnostic value of single-voxel 1H-MR spectroscopy in determination of head and neck malignant tumors. Methods: Twenty-three patients who had head and neck tumors were selected for this retrospective study. The tumors were confirmed histopathologically, including ten squamous cell carcinomas (SCC), seven epithelial malignant tumors of salivary gland, four sarcomas and two non-Hodgkin's lymphomas. All the tumors were examined with single-voxel 1H-MR spectroscopy before the operations. Single-voxel 1H-MR spectroscopy was performed at 1.5 T with a surface coil by using a point-resolved spectroscopy (PRESS) with echo time of 144 or 288 msec (23 subjects) and a stimulated echo acquisition (STEAM) with echo time of 30 msec (16 subjects). Chorine (Chr), one of tumor's metabolites was evaluated to determine if malignant signs were presented. The peak of Chr was at 3.2 ppm. Results: When PRESS was applied, the peak of Chr was identified in seven of ten (70%) SCCs, two of seven (28.6%) epithelial malignant tumors of salivary glands, three of four (75%) sarcomas and two of two (100%) non-Hodgkin's lymphomas respectively. When STEAM was utilized, the peak of Chr was detected in three of seven (42.9%) SCCs, one of five (20%) epithelial malignant tumors of salivary glands, and one of four (25%) sarcomas. The Chr peak in all the five tumors shown in STEAM was also detected in PRESS. Conclusions: Based on the above-mentioned results, PRESS was more sensitive than STEAM in detection of head and neck malignant tumors. With the exception of epithelial malignant tumors of salivary glands, PRESS was valuable in diagnosis of the head and neck malignant tumors.