The Application Of DWI And MRS In Diagnosis And Differentiating Of Breast Lesions

With the improvement of people’s living standard, the outbreak of breastdiseases like breast cancer is growing year by year. As a result, it is ofincreasing importance to instantly and correctly distinguish benign andmalignant breast diseases which are treated differently. As is known, differentpatients of breast cancer have different clinical performance and biologicalfeatures, so it is no longer enough to only rely on surgical doctors by palpation.While the imaging examination plays a key role in the diagnosis of benign andmalignant breast diseases. In the past, the imaging diagnosis of breast mainlytook X-ray imaging and color sonography. While the new emerging ofmolecular imaging greatly improves the diagnosis, which successfully transfersfrom morphological observation to molecular imaging research and lead thediagnosis and distinguish of breast diseases into a new age---the combination ofmorphology and functional imaging.Objectives: Discuss the parameter change discipline of MRI, DWI andMRS of breast benign and malignant diseases, and evaluate the applicationvalue of MRI, DWI and MRS to the diagnosis and differential diagnosis ofbreast benign and malignant tumors so as to provide many other noninvasivemethods for the diagnosis and more reliable imaging data.Materials and Methods:1. Materials: Collect the MRI, DWI and MRS data and clinical data of90cases from February to March2010in our hospital that were suspects of breasttumors, with49of them having been affirmed with breast diseases by surgicaloperation or biopsy,23cases being benign and26being malignant. And thenanalyze retrospectively.2. Inspection equipment: GE1.5T TX Horizon MRI equipment (phased-array surface coil pairs of bilateral breast imaging) and SunMicrosystem AdvantageRelease AW2.0.3. Method: The patients lie in prone position and the breast naturally hangin the phased-array surface coil pairs and the supporting holes. Take regular3-plane positioning of T1WI, T2WI-FS flat imaging, DWI and MRS. Decidescanning sequence and parameters by referring to the documents.4. Imaging Evaluation:（1）The imaging data of the49cases in thisstudy is examined by two senior MRI doctors.（2The49cases have completeimaging and pathological data. The diagnosis of benign and malignant diseasesis decided by observing the MRI imaging, measuring DWI and ADC andwhether the MRS reaches tCho; compared with the golden standard ofpathological results, this study comes to the sensitivity, specificity andaccordance rate of MRI, DWI, MRS and MRI+DWI+MRSResults:1. By MRI,26cases are diagnosed as malignant, and6of them are provedas benign by pathology. By MRI,23cases are diagnosed as benign, and6ofthem are proved as malignant by pathology. So the sensibility is76.92%, thespecificity is73.91%, and the accordance rate is75.51%.2. By DWI,24cases are diagnosed as benign, and5of them are proved asmalignant by pathology. By MRI,25cases are diagnosed as malignant, and4ofthem are proved as benign by pathology. So the sensibility is80.77%, thespecificity is82.61%, and the accordance rate is81.63%.3. By MRS,23cases are diagnosed as benign, and3of them are proved asmalignant by pathology. By MRS,26cases are diagnosed as malignant, and3of them are proved as benign by pathology. So the sensibility is88.46%, thespecificity is86.96%, and the accordance rate is87.76%.4. By MRI+DWI+MRS,23cases are diagnosed as benign, and2of themare proved as malignant by pathology. By MRI+DWI+MRS,26cases are diagnosed as malignant, and2of them are proved as benign by pathology. Sothe sensibility is92.31%, the specificity is91.30%, and the accuracy rate is91.84%.Conclusions:1. MRI can clearly show the anatomical position of the benign andmalignant lesions of breast, the early changes of the lesions and the adjacentinvasion and transfer. But it cannot show the calcified lesions, especially theunclear lump in galactophore and the small lumps.2. In DWI diagnosis, ADC values of benign and malignant lesions aredifferent. In the ADC diagram, malignant pathological changes have low signalwhile the benign ones have the signal that is slightly lower than that of thegland.3. In MRS, the sensibility, specificity and accuracy rate are88.46%,88.96%, and87.76%respectively. It also has some short comes such as itrequires particular techniques, abundant prescan water suppression and fatsuppression, even magnetic field and is not sensitive to small lesions butsensitive to the moving height of the patients while scanning. Meanwhile, itsometimes comes to some false results, as the benign tumors or the benignlesions can grow fast in a short time and show the Cho peak in MRS.4. In MRI+DWI+MRS diagnosis, the sensibility, specificity and accuracyrate are the highest compared with MRI, DWI and MRS respectively.In this study, we evaluate the accuracy of1.5T MRI, DWI and MRS tobreast benign and malignant pathological changes. Though there have beenmany studies on breast MRI, the sensibility, specificity and accuracy rate of themethod in this study are higher than those of other examination methods. Thismethod can also avoid the invasive examination. So the MRI examination ofbreast should be applied as the routine examination means of breast diseases. Conclusion: The1.5T MRI has high specificity in diagnosing breastbenign and malignant diseases. MRI is an effective imaging method todiagnose breast cancer. Especially the application of DWI and MRS can greatlyenhance the sensibility and specificity, thus being the best imaging means ofdistinguishing benign and malignant diseases of breast.