1. Comparison of 1.5 and 3.0 Diffusion-weighted MR Imaging for Brain Tumors
Merhemic Z¹, Gavrankapetanovic F¹, Bilalovic N¹, Nikšić M¹, Kadenic Z¹, Thurnher MM².
¹Clinical Centre University Sarajevo, Bosnia & Herzegovina
²University Clinic Vienna, Austria

2. The specificity and senzitivity of diffusion-weighted MR imaging in evaluatio of cerebral diseases is well-established
DWI has become an essential part of routine diagnostic sequences in MRI.

3. DWI has been used to study brain tumors ,
has been reported its diagnostic potential and usefulness for obtaining the apparent diffusion coeffitient (ADC).

4. There appears to be a corelation between qualitative and quantitative assessment of the ADC map and the tumor cellularity and tumor grade.
Tumors with higher cellularity or higher grade show increased signal on DWI and marked reduction in ADC value. On contrary tumors with low cellularity have a significantly higher ADC values.

5. The aim of this study was to compare apparent diffusion coefficient (ADC) values of brain tumors measured on 1.5T and 3.0T MRI.

6. Materials and Methods:
34 patients, 18 female, 16 male
Range age 7 to 74 years
Conventional MR sequences:
T1, T2, Flair, T1 afret CA
DWI seq. at both 1.5 and 3T MR

7. Histological analysis revealed
7 meniniomas
6 glioblastomas
3 astrocytomas G3
5 astrocytomas G2
7 metastasis
1 oligodendroglioma, meduloblastoma, chorioid plexus papilloma, craniopharingeoma, lymphoma, schwannoma

8. 3 region of interest (ROI) were placed in the solid tumors parts of ADC maps
Mean ADC value was calculated for each tumor on
1.5 and 3.0 T unit

9. Results
The mean ADC of meningiomas was 0.88×10ˉ³ mm²/s on 1.5T and on 3.0T unit

10. glioblastomas G4 1.5×10ˉ³ mm²/s on 1.5T and 1.6 ×10ˉ³ mm²/s on 3.0T
astrocytomas G3 0.92×10ˉ³ mm²/s on 1.5T and 0.90×10ˉ³ mm²/s on 3.0T unit;
astrocytomas G2 1.4×10ˉ³ mm²/s on 1.5T and 3.0T unit;

11. metastatic lesions 1.1×10ˉ³ mm²/s 1.5T and 3.0T

12. oligodendroglioma was 1.0×10ˉ³ mm²/s on 1.5T and 3.0T unit;
of meduloblastoma 1.7×10ˉ³ mm²/s on 1.5T and 2.0×10ˉ³ mm²/s on 3.0T

13. choroid plexus papilloma 0.9×10ˉ³ mm²/s on 1.5T and 3.0T
craniopharyngeoma 1.8×10ˉ³ mm²/s on 1.5T, and on 3.0T unit
lymphoma 0.89×10ˉ³ mm²/s on 1.5T, and 0.79×10ˉ³ mm²/s on 3.0T
schwannoma 0.8×10ˉ³ mm²/s on 1.5T and 3.0T.

14. Statistical analysis showed good agreement p=0. 849 (T=1157
Statistical analysis showed good agreement p= (T= Mann-Whitney Rank Sum Test) between measurements when comparing 1.5 and 3.0 T .

15. Despite small number of cases in this study, the results of ADC measurements in brain tumors show good agreement between 1.5 T and 3.0T MRI unit. Further studies with larger patient sample are neceassary for more solid conlusions