Proton spectroscopy findings of meningioma

Objective To evaluate the characteristics of 1HMRSI and its diagnostic value on meningioma. Methods The findings of conventional MRI and of 1HMRSI from 11 cases of clinically proven meningiomas and from 12 normal volunteers were comparatively analyzed. The imaging sequences included T 1-weighted imaging and T 2-weighted imaging; additionally T 1-weighted imaging with injection of the contrast agent of Gd-DTPA was performed in all meningioma cases. Two-dimensional phase encoding of proton magnetic resonance spectroscopic imaging (2D 1HMRSI) were obtained in all cases. Results On conventional pre-contrast MRI, the signals in 8 meningioma cases showed medium or faintly low intensities and in 3 cases showed mixed intensities on T 1WI. On T 2WI, the signals in 7 cases showed medium or faintly high intensities and in 4 cases showed mixed intensities. After injection of Gd-DTPA, the solid portion of tumors exhibited obvious enhancement in all meningioma cases. “Dural trail sign” was revealed in 7 cases. Peri-tumor edema was evident in 11 meningioma cases. Compared with control group, 1HMRSI of all meningiomas revealed different spectral peaks, including absent acetylaspartate (NAA), prominent choline (Cho), and reduced phosphocreatine (Pcr). The ratios of Cho/Pcr obviously increased. The peak of lactate (Lac) was visualized in 2 meningioma cases. Conclusion Most cases of meningioma can be diagnosed with conventional magnetic resonance imaging (MRI). 1HMRSI can yield more informative findings about meningioma via the observed metabolic materials changes in tumor cells. So conventional MRI is the most important technology for diagnosing meningioma and 1HMRS combined with MRI can improve the diagnostic accuracy. 1HMRSI can be an important supplemental means in the diagnosis of meningiomas.