The Application Of DWI And MRS In Diagnosis And Differentiating Of Prostate Diseases

With the worldwide average life have extended and the improvement ofpeople's living standard, prostate cancer (PCa) and benign prostatic hyperplasiaBPH) become common disease in older men. PCa have different natural courseand difference prostate cancer's biological characteristics and clinicalmanifestations have significant difference.Objectives: With improving of imaging technology currently, makes thePCa living diagnostic level get unprecedented increase. Discuss the parameterchange discipline of MRI, DWI and MRS of Prostate Cancer, and evaluate theapplication value of MRI, DWI and MRS to the diagnosis and differentialdiagnosis of prostate benign and malignant tumors.Materials and Methods: Collect the MRI, DWI and MRS data andclinical data of 65 cases affirmed as prostate cancer by puncture or surgicalpathology in China-Japan Union Hospital of Jilin University in recent threeyears, and analyze retrospectively. Patients'age is from 44-83, and the averageage is 66.4, whose clinical symptoms are frequency of micturition; urgency ofurination; urodynia; dysuria anamorphosis; PSA (prostate specific antigen)raised.When patients make an appointment, informing patients eat less foodproxima luce and evacuation urine and stool before check. Gently discharge thegas of the top coil balloon and put a rubber sheath with evenly paraffin oil onthe rectum coil before plug the coil in the rectum.Patient lie left lateral decubitusright lateral decubitus on examinating couch, whose hands peripatellapexylike a bow. Doctor adjust the direction of the coil, and insert the coil into therectum slowly. When the coil gets into the right position, injection about 60- 80 ml air to the balloon. After checking, first completely deflated the balloon,and then remove the coil.In this study, GE 1.5T (upgraded to 3.0T) MRI machine scanned; Allpatients use MRI scan sagittal view; axial view and coronal view by abdominalcoil.Scanning parameters: T₂WI using fast spin echo (FSE) (TR: 4000ms, TE:85ms); T₁WI using spin echo (SE) (TR: 500ms, TE: 14ms); thickness: 5.0mm;layer interval: 1.0 mm; FOV: 36.DWI scanning parameters:Pulse sequence:EPIï¼›Pulse Seq family:EchoPlanar Imagingï¼›b-value:800s/mm²,1000s/mm²ï¼›TE:Minimumï¼›TR:3000msï¼›FOV:17.0.MRS scanning parameters: Pulse sequence:proseï¼›Pulse Seq Family:Spectroscoyï¼›TE:130.0ï¼›TR:1000.0ï¼›NEX:1.00ï¼›Voxel Thicked:24.0ï¼›CSI slicethicked: 10.0ï¼›Fov:11.0.ADW 4.4 workstation and GE Functool software for data analysis.SPSS16.0 software package was applied to statistical in both parts of study.Measurement data contrast use t-test, and enumeration data comparison withchi-square test. Statistically significant difference was defined as P value lessthan 0.05.Results:1. MRI multi-sequence and multi-direction imaging can clearlyshow the gland and surrounding anatomical structure, but cannot accuratelydiagnose the PCa in the central zone and the stromal BPH in the peripheral zone.By MRI, 30 cases are diagnosed as PCa, and 5 of them are proved as BPH bypathology; By MRI, 35 cases are diagnosed as BPH, and 5 of them are provedas PCa by pathology. In diagnosing PCa by MRI, the sensibility is 83.33%, thespecificity is 85.71%, and the accordance rate is 84.62%.2. The ADC of Pca cancer focus is significantly lower than that of thegrowth growths and central gland and its surrounding zone, which is ofstatistical significance (p<0.05). When the b-values are different, ADC upper limits of the PCa cancer focus are 0.73×10^-3 mm²/s (b-value is 1000 s/mm²) and0.76×10^-3 mm²/s (b-value is 800 s/mm²) respectively, and both of them arelower than 1.0×10^-3 mm²/s; within the same zone (normal peripheral zone, BPHfocus and PCa cancer focus) with different b-values (800 s/mm² and 1000s/mm²), ADC doesn't have significant differences statistically (p>0.05). ByDWI, 31 cases are diagnosed as PCa, and 5 of them are proved as BPH bypathology; By DWI, 34 cases are diagnosed as BPH, and 4 of them are provedas PCa by pathology. In diagnosing PCa by DWI, the sensibility is 86.67%, thespecificity is 85.71%, and the accordance rate is 86.15%.3.(Cr+Cho)/Cit value of prostate MRS Pca group is significantly higherthan that of the other two groups. The ratio of PCa group is 2.76±1.38; the ratioof BPH group is 0.51±0.23; the ratio of normal central gland group is 0.40±0.14;the ratio of normal peripheral zone is 0.39±0.15. By MRS, 10 cases arediagnosed as PCa, and 2 of them are proved as BPH by pathology; By MRS, 7cases are diagnosed as BPH, and 1 of them are proved as PCa by pathology. Indiagnosing PCa by MRS, the sensibility is 88.89%, the specificity is 75.0%, andthe accordance rate is 82.35%.4. By a combination of MRI, DWI and MRS, 10 cases are diagnosed asPCa, and 1 one of them is proved as BPH. By a combination of MRI, DWI andMRS, 8 cases are diagnosed as BPH, and 1 one of them is proved as PCa.Indiagnosing PCa by the combination of MRI, DWI and MRS, the sensibility is90.0%, the specificity is 87.5%, and the accordance rate is 88.89%. Comparedwith those of MRI, DWI and MRS, all indexes are enhanced by means of thecombination of the three.Conclusion: 1,MRI multi-sequence and multi-direction imaging canclearly show the gland and surrounding anatomical structure, as well as focus'sprophase change; hemorrhage; iquefaction; necrosis and so on imagingcharacteristic, but cannot accurately diagnose the PCa in the central zone and the stromal BPH in the peripheral zone.2,The ADC of Pca cancer focus is significantly lower than that of thegrowth growths and central gland and its surrounding zone. Therefore, littlemorphological changes BPH and normal prostate in the diagnosis anddifferential diagnosis need a large sample of patients to be further statisticalresearch in the DWI.3,(Cr+Cho)/Cit value of prostate MRS Pca group is significantly higherthan that of the other two groups, which is of statistical significance (p<0.05).Our conclusion with the literature [1] is consonance. The reference value ofChinese human prostate's MRS are: the (Cho + Cr) / Cit ratio of <0.75 forbenign prostate disease; the ratio of 0.75-0.86 for the suspected cancer; the ratioof > 0.86 for the positive cancer.4,In diagnosis By a combination of MRI, DWI and MRS:â‘ Comparedwith those of MRI, DWI and MRS, all indexes are enhanced by means of thecombination of the three.â‘¡It can visualized evaluation BPH and Pca'sPathophysiology and biochemistry Metabolism change.The combination of MRI, DWI and MRS can distinguish prostate benignand malignant tumors at the molecular level, and it is an effective imagingmethod to diagnose BPH and PCa. It offers reliable evidences to the diagnosisand differential diagnosis of prostate benign and malignant tumors, havingguiding significance to clinical treatment choice and prognostic evaluation.