| With the rapid development of the field strength improved, new sequences (EPI sequence) and the software and hardware of computers, the functional magnetic resonance imaging (DWI and PWI) have been employed in the clinic mostly. It can overcome the disadvantage that positron emission tomography (PET) and single photon emission computed tomography (SPECT) need the radioactive trace agent and have lower spatial resolution. Because of having higher temporal resolution and higher signal to noise ratio (SNR), it have been used in the study of cerebral diseases ( superacute cerebral infarction and cerebral tumors), breast neoplasm, liver diseases, bone and soft-tissue neoplasms. Especially, the study of hyperacute cerebral infarction and cerebral tumors have obtained some valuable conclusions. However, we only found five literatures in the foreign journals about studying the prostatic diseases, and did not find one literature in our national journals. So we designed this study.Objective: Firstly, to explore the average value of apparent diffusion coefficients in the central gland and peripheral zone of the normal prostate respectively, when using diffusion-weighted imaging. Secondly, to study the steepest slope of signal intensity-time curve and change in T2 relaxation rate in perfusion-weighted imaging. Thirdly, to research the application of diffusion-weighted and perfusion-weighted MR imaging in the prostatic diseases, and evaluate the correlation of DWI and PWI features with vascular endothelial growth factor (VEGF) and microvessel density (MVD).Materials and Methods: In the first time, selecting thirty healthy volunteers who were not suffered from the prostatic diseases, age from twenty to forty years old. We made routine MRI scan and scanned them with DWI and PWI respectively. In the second time, fifty-seven consecutive patients who were diagnosed clinically for the prostatic diseases, including forty-two cases with benign prostate hyperplasia and fifteen cases with prostate cancer proved pathologically, were examined by DWI and PWI. MVD and VEGF were stained with immuno -histochemical methods. Some parameters of DWI and PWI, includingapparent diffusion coefficients (ADCs), the steepest slope of signal intensity-time curve (SSmax) and AR2*peak at lesions, were put more analyses. Correlation analysis was used to determine the relation between the results of DWI, PWI and that of immuno -histochemistry. Results: (1)The average apparent diffusion coefficients of the central gland, peripheral zone of the normal prostate and internal obturator muscle was 1.883±0.37mm2/s, 2.254±0.77mm2/s, 1.021±0.35mm2/s respectively; in the benign prostate hyperplasia groups respectively: 1.783±0.282mm2/s, 2.025±0.358mm2/s, 1.019±0.23mm2/s; in the prostate cancer groups respectively: 1.632±0.082mm2/s, 0.267±0.07 mm2/s, 1.020±0.25mm2/s. The average apparent diffusion coefficients of peripheral zone in the prostate cancer was significantly lower than those of the benign prostate hyperplasia(P<0.05). (2)In the normal prostate, the steepest slope of signal intensity-time curve (SSmax) of the central gland and peripheral zone was 0.38±0.01,0.43±0.01 respectively, and AR.2*peak was 0.18±0.05,0.20±0.07 respectively; in the benign prostate hyperplasia, SSmax and AR.2*peak were 33.5±3.1, 1.5±0.1 respectively; however, in the prostate cancer respectively: 57.8±5.0, 3.0±0.6; There were statistical difference(P<0.05). (3)The VEGF and MVD expression of 15 Pea patients were significantly higher than those of 42 BPH patients(P<0.01). MVD expression of Pea and BPH showed an positive association with VEGF expression (P<0.01). On DWI, The average apparent diffusion coefficients showed no association with MVD and VEGF expression(P>0.05), but, on PWI, SSmax and AR.2*peak showed an association with MVD and VEGF expression(P<0.05).Conclusions: (l)DWI could give quantitative information for their pathological changes in BPH and Pea. ADCs is an effective parameter in discriminating malignant and benign prostate lesions.
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