Field-of-view optimized and constrained undistorted single shot intravoxel incoherent motion diffusion-weighted imaging of the cervix during the menstrual cycle: A prospective study.

Objective: To provide insight into the biological characteristics of the healthy cervix by defining intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) parameters across the menstrual cycle.

Methods: Forty-three females of reproductive age (18-45 years old) were included in this prospective study. Conventional magnetic resonance imaging (MRI) and IVIM-DWI scans were performed at multiple time-points across the menstrual cycle: T (menses), T (follicular phase), T (luteal phase). Intra- and interobserver repeatability of the IVIM-DWI values were evaluated with intraclass correlation coefficients (ICC), and D* was excluded from the analyses due to poor repeatability. Differences in each IVIM-DWI parameter among T, T, and T were explored. Subjects were stratified by age and parity for subgroup analyses (younger [18 - < 30 years] vs. older [≥30-45 years]; parity 0 vs. parity 1 and 2). Correlations between subject age and IVIM-DWI parameters were assessed. The overlap for each IVIM-DWI parameter among T, T, and T was evaluated.

Results: ADC and D values of the cervix were significantly lower at T compared with T (p = 0.02 and 0.03) or T (p < 0.01 and < 0.01). In younger subjects (n = 26), ADC and D values were significantly lower at T compared with T (p < 0.01 and p = 0.02) or T (p = 0.03 and p = 0.04). In older subjects (n = 17), ADC values were significantly higher at T compared with T (p = 0.01) or T (p = 0.01). There were significant differences in ADC values at T in subgroup analyses stratified by age and parity (both p < 0.01). There was a moderate correlation between age and ADC values at T. Overlap for IVIM-DWI parameters across the menstrual cycle was >50%.

Conclusion: ADC and D values of the heathy cervix differed across the menstrual cycle. Age and parity may influence the ADC value.