MRI And DWI Study Of Aging Prostate Changes

Objective:Using the magnetic resonance imaging(MRI)and diffusion weighted imaging(DWI)to examine normal prostate gland in each age section and analyze their signal characteristics.To investigate the aging procedure and evolution rule of prostate with MRI and DWI initially.Methods:To examine the 267 healthy volunteers without prostate gland related disease,other urinary system disease and body-wide disease with MRI and DWI. They were divided into 5 groups according to the age:20～29 year old(56);30～39 year old(50);40～49 year old(50);50～59 year old(59);above 60 year old(52).The contents of observation and measurement included the prostate gland's MRI signal appearance and their characteristic with aging;to survey the diameter line of prostate gland(Length,Width and Height)and compute volume,then analyze the characteristic in various age group;to observe the DWI signal intensity and the evolution characteristic in different age and b value;to survey ADC value of prostate gland and analyze the evolution characteristic of its change associated with age and b value.To use the normal distribution method((?)±1.96s)to count the diameter line, volume and ADC value.To use ANOVA and LSD to analyze diameter line,compute volume and ADC value.To use the paired T-test to analyze the ADC value from PZ and CG under the same age and b value condition.Supposition examination significance level wasα=0.05Results:1.MRI appearance of the prostate glandPeripheral zone's signal was higher than that of central gland on T₂WI,the peripheral zone's signal increased gradually with aging while the central gland's signal did not change obviously.Peripheral zone's signal weakened gradually with aging on T₁ WI, especially after 40 years old.Central gland's signal did not weaken obviously.2.The results of diameter line and volume statisticsThe diameter line and volume of prostate gland were growing with aging. Comparison result showed that the statistics significance was present between two age groups(P＜0.05),except those between 50～59 year old and above 60 year old, (P＞0.05).3.The result of DWIThe signal in peripheral zone was high while the signal in central gland showed low signal.The median line area of the prostate gland showed linear high signal.The signal of peripheral zone in the same age group decreased prominently associated with increase of b value,central gland's signal did not decrease obviously.In the same age,peripheral zone's signal weakened with increase of the b value.In the same b value,peripheral zone's signal weakened with increase of the age.Central gland's signal did not change obviously.4.The results of measurement of ADC value and statisticsThe comparison of peripheral zone's and central gland's ADC showed statistics significance under the same age and b value condition,(P＜0.05).Comparison of PZ's ADC value under the same age and different b value condition showed statistics significance except between b= 800s/mm² and b=1000s/mm²,(P＞0.05).Comparison of CG's ADC value under the same age and different b value condition showed statistics significance between two random groups(P＜0.05).Comparison of PZ's ADC value under the same b value and different age condition showed statistics significance between random two groups(P＜0.05).Comparison of CG's ADC value under the same b value and different age condition showed statistics significance between two random groups,(P＜0.05).Conclusion:(1)Peripheral zone's signal increases gradually following increase of age on T₂WI,central gland's signal does not increase obviously.(2)Peripheral zone's signal weakens gradually following increase of age on T₁WI,central gland's signal does not weaken obviously.(3)The diameter line and volume of prostate gland grows gradually following increase of age.(4)In the same age,peripheral zone's signal weakens on DWI with increase of b value.(5)In the same b value,peripheral zone's signal weakens on DWI with increase of age.(6)Central gland's signal does not change obviously with increase of age and b value.(7)PZ's and CG's ADC value decreases following b value up in the same age group,but the difference of PZ's ADC.is not obvious between b=800s/mm² and b=1000s/mm².(8)PZ's and CG's ADC value increases following the age up in the same b value. Innovation points(1)To study the MRI and the DWI of normal adult prostate gland systematically and foremosfly in China.(2)To research the evolution rule of DWI signal and the ADC value from normal adult prostate gland systematically correlated with age and b value fore mostly.(3)To discovery the difference of signal between PZ and CG will be obvious after 40 years old foremostly on T₁WI.