Xiang Liu, Presenter: Nothing to Disclose

Wei Tian MD, PhD, Abstract Co-Author: Nothing to Disclose

Sven E. Ekholm MD, Abstract Co-Author: Nothing to Disclose

The aim of the study was to study perfusion and diffusion characteristics of intra-axial tumors and tumor like lesions (TLL) in the medulla oblongata and the cervical spinal cord.

There were 19 patients with mass lesions in the cranio-cervical junction region who had been examined with dynamic susceptibility contrast (DSC)-GRE-PWI and cervical DTI (EPI sequence TR/TE=10000/85, b=1000s/mm2, 25 directions; FOV 20) besides conventional MRI. Eight of the patients had histoligally confirmed intramedullary tumor, including three of the astrocytomas presented as non-enhancing mass lesions. There were 11 cases of TLL. Trace apparent diffusion coefficient (trace ADC), fractional anisotropy (FA) and relative cerebral blood volume (rCBV) were calculated using Functool on a GE workstation. Statistical comparison of all these parameters, and the ADC and FA ratios were assessed using the Mann-Whitney test.  

Mean rCBV of the tumors was significantly higher (1.77±0.7) than that of the TLL (0.49±0.19, P <0.001). The mean rCBV of non-enhancing astrocytomas were lower (1.23±0.2) than that of the enhancing tumors (2.09±0.71, P value of 0.07). The mean ADC values of both TLL (0.806±0.116) and tumors (1.103±0.322) were higher than that of the surrounding tissue (0.690±0.1). of TLL with P value of 0.006, 0.885±0.317 in the tumors with P value of 0.138), the mean FA values of tumor like lesions(0.402±0.105) and tumors(0.254±0.087) are higher than the surrounding tissues(0.599±0.121 with P <0.001, 0.332±0.134 with P value of 0.134, respecitvely). The differences in mean ADC and mean FA values between non-neoplastic and neoplastic mass lesions were significant with P values of 0.03 and 0.006, respectively. However, there was no significant difference for ADC- and FA- ratios (P values = 0.284 and 0.738, respectively). Two of the astrocytomas had increased FA values within the lesion (FA ratios were 2.11 and 1.19), which may indicate that tumor contained encapsulated fibers.

Combining information from MR-PWI and -DTI may be helpful to differentiate between mass lesions in the cranio-cervical junction region.

Combining MR perfusion weighted imaging and diffusion tensor imaging may be useful in differentiating between intra-medullary mass lesions of cranio-cervical junction region.

Liu, X, Tian, W, Ekholm, S, MR Perfusion Imaging and Diffusion Tensor Imaging of Intraaxial Tumors and Tumor-like Lesions of the Medulla Oblongata and the Cervical Spinal Cord.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8012529.html