Abstract
OBJECTIVE: To explore the utility of diffusion-weighted imaging (DWI)-derived apparent diffusion coefficient (ADC) and exponential apparent diffusion coefficient (eADC) parameters in differentiating mega cisterna magna (MCM) from cisterna magna arachnoid cysts (CMAC). METHODS: Retrospective analysis of MRI data from 40 MCM patients, 46 CMAC patients (confirmed via clinical follow-up and imaging criteria), and 36 temporal arachnoid cysts (TAC) as controls was performed. Independent sample t-tests were used to compare ADC and eADC values among the three groups. RESULTS: The eADC values of MCM, CMAC, and TAC were (3.75 ± 0.27) × 10(-2), (4.53 ± 0.54)×10(-2), and (4.35 ± 0.30) ×10(-2) mm(2)/s, respectively. There was no significant difference in the eADC value between CMAC and TAC (p = 0.191). However, the eADC value of MCM was significantly different from the two groups (p = 0.000). The ADC values of MCM, CMAC, and TAC were (3.30 ± 0.08) × 10(-3), (3.11 ± 0.12) ×10(-3), and (2.97 ± 0.71) × 10(-3 )mm(2)/s, respectively. Significant differences in ADC were observed between MCM and both CMAC and TAC (p = 0.000/0.003). CONCLUSION: DWI-derived ADC and eADC parameters can effectively differentiate mega cisterna magna from cisterna magna arachnoid cysts.