The Evolvement Of Signal Intensity On Diffusion Weighted Imaging Before And After Menopause And Its Relationship To Sex Hormone Level

Objective: The study is to analyze the influence of serous estradiol(E2),follicule stimulating hormone(FSH)and luteinizing hormone(LH)level to the signal intensity of diffusion weighted imaging(DWI)and apparent diffusion coefficient(ADC)of lumbar vertebra bone marrow in health women for a correct interpretation of the evolvement of signal intensity in normal lumbar vertebra bone marrow on DWI before and after menopause,therefore to differentiate the normal from pathologic bone marrow images correctly.Methods: A total 70 healthy women(aged between 40 and 58 years old)participated in the study.All volunteers underwent conventional MRI,DWI and T2 mapping of lumbar vertebra at 1.5T MR scanner,at the same time they underwent bone mineral density(BMD)test of lumbar vertebra by quantitative CT and blood assay the serous level of E2,FSH and LH.We visually evaluated that if the signal intensity of lumbar vertebra bone marrow on DWI images were hyperintensity or hypointensity.The hyperintensity is definited as that higher than the signal intensity of muscle and hypointensity equal to or lower than the signal intensity of muscle.All women wrote the questionnaire,and the hyperintensity on DWI divided into groups according to the BMI,age at menarche,menstyual blood volume,parity,abortion,menopausal status,drinking milk and walking.The signal intensity value on DWI,the ADC value,the T2 value and the BMD were measured on the lumbar vertebra from second to the fourth vertebral bodies.We use ANOVA and Student-Newman-Keuls tests to analyse the any difference of ADC value,T2 value and BMD among premenopausal,perimenopausal and postmenopausal,and use Kruskal-Wallis test to analyse the signal intensity value on DWI.The relationship between the serous level of E2,FSH,LH andage,the ADC value,the T2 value,the signal intensity value,the BMD are analyzed.The relationship between the signal intensity value and T2 value,ADC value are also analyzed.The correlation between the ADC,the T2 value,the signal intensity value,the BMD of bone marrow and age are analyzed.Result: The visual evaluation results of DWI images indicates that bone marrow in 41 women showed hyperintensity and 29 women showed hypointense,the E2 level of the two groups is respective 84.57 pmol/L and24.21 pmol/L,and there is obvious difference between them.The proportion of hyperintensity on DWI in the premenopausal is 91%,in the perimenopausal is 75% and in the postmenopausal is 8%.The women is in the menopause,the proportion of hyperintensity on DWI is gradually reducing.The hyperintensity has nothing to with the BMI,age at menarche,menstyual blood volume,parity,abortion,drinking milk and walking,perhaps the women is too little at each group.Student-Newman-Keuls test reveals that no significant difference was found in the ADC,and significant difference was found in the signal intensity value,the T2 value and BMD among premenopausal,perimenopausal and postmenopausal.There is significant negative correlation between E2 level and age,and significant positive correlation between E2 level and the signal intensity value,the T2 value and BMD.There is significant positive correlation between FSH level and age,and significant negative correlation between FSH level and the signal intensity value,the T2 value and BMD.There is significant positive correlation between LH level and age,and significant negative correlation between LH level and the signal intensity value,the T2 value and BMD.There are no significant correlation between E2,FSH,LH and the ADC.There are significant negative correlation between the signal intensity value,the T2 value and BMD and age,there is no correlation between the ADC and age.There is significant positive correlation between the signal intensity value and T2 value,but no significant correlation the signal intensity value and ADC value.Conclusion: With the age growing,the E2 level is decreasing,and water content in the bone marrow is also decreasing,the signal intensity on DWIdescend.With the E2 level decreasing,mesenchymal stem cell divide fat cell,and the BMD also descend.The signal intensity of DWI and BMD of lumbar vertebra bone marrow are different among premenopausal,perimenopausal and postmenopausal.,but the ADC value is not different among above groups.The signal intensity of DWI and BMD is also affected by age,but the ADC value is not affected by age.