Measurement reproducibility of parameters derived from introvoxel incoherent motion diffusion-weighted MRI imaging of rectal cancer / 中华肿瘤杂志

Objective@#To study the measurement reproducibility of parameters derived from introvoxel incoherent motion (IVIM) diffusion-weighted imaging (DWI)-MRI of rectal cancer between- and within- radiologists.@*Methods@#Clinical data of 34 patients with rectal cancer were prospective analyzed. Conventional MRI sequences, IVIM DWI-MRI with sixteen b values and dynamic contrast enhancement (DCE)-MRI sequences of rectum were acquired by GE 3.0-T MRI imager. The IVIM sequence images with b value=1000 sec/mm2 were selected to measure the maximum axial section of tumor by a radiologist with 15 year-experiences in gastrointestinal cancer imaging.Two radiologists (radiologist 1 and radiologist 2 with 2 and 10 years of experience in gastrointestinal cancer imaging, respectively) independently draw a freehand region of interest (ROI) that contained the largest available tumor area on the selected section. Monoexponential apparent diffusion coefficient (ADC) and biexponential IVIM metrics maps and IVIM parameters were generated automatically by the software. The repeated measurement was performed at an interval of one week. The average values of each measurement were used for statistical analysis. ADC values and IVIM parameters obtained between- and within- radiologists were analyzed by Wilcoxon signed-rank test. Intraclass correlation coefficients (ICC) and Bland-Altaman plots were used to analyze the parameter reproducibility of two measurements between- and within- radiologists.@*Results@#The first and second measured ADC (×10-3mm2/s), true diffusivity (D, ×10-3mm2/s), false diffusivity (D*, mm2/s) and perfusion fraction (f, %) by radiologist 1 were 0.997, 0.692, 0.043, 34.6 and 0.993, 0.691, 0.038, 32.8, respectively. The first and second measured ADC (×10-3mm2/s), D (×10-3mm2/s), D* (mm2/s), f (%) by radiologist 2 were 0.987, 0.651, 0.046, 32.8 and 0.996, 0.689、0.041, 32.7, respectively. No statistically significant differences were observed in ADC and IVIM parameters obtained between- and within- radiologists (P>0.05). The ADC values and the f values of two times were significantly correlated between- and within- radiologists. The D values were significantly correlated within a radiologist, and the correlation of D* values within a radiologist was significantly higher than that between radiologists. The 95% limits of agreement (LoA) of ADC values and f values were smaller than those of D values and D* values between- and within- radiologists. The 95% LoA of ADC values was the least, while that of D* values varied most.The 95% LoA of f values and D values kept steady within a radiologist, and 95% LoA of f values was slightly smaller than that of D values. The 95% LoA of IVIM parameters (ADC, D, f, D* values) within radiologists 2 were better than those within radiologist 1.@*Conclusions@#The reproducibilities of ADC and f values are the best, while the reproducibility of D* values is relatively poorer in rectal cancer. Measurement reproducibility of parameters derived from IVIM may be improved by increasing radiologists’ experiences in drawing ROI.

The progress in diffusion technologies in the diagnosis of breast cancer / 实用肿瘤学杂志

In recent years ,the diffusion magnetic resonance imaging in the study of breast cancer is in-creasing,which including diffusion weighted imaging ,diffusion tensor imaging ,intravoxel incoherent motion ,and diffusion kurtosis imaging .The emergence and development of these technologies can be noninvasive quantitative evaluation of breast tumors from the molecular level .The researchers pay more and more attention to the applica-tion of breast cancers diagnosis and differential diagnosis ,therapeutic effect ,prognosis evaluation and so on .This paper reviews the progresses of the above four technologies in the use of the breast cancer .

Validación y consistencia del test de exploración visual de la percepción del movimiento / Validation and consistency of the visual exploration test of movement perception

Se realizó una investigación analítica y prospectiva para validar el test de exploración visual de la percepción del movimiento mediante el método de experto, así como determinar su confiabilidad y consistencia interna a partir del alfa de Cronbach, desde junio de 2013 hasta igual periodo de 2014. Su aplicación incluyó inicialmente un pilotaje para lograr homogeneidad, y en la segunda etapa se seleccionaron 144 niños de 9-11 años, pertenecientes a la Escuela Primaria "Nguyen Van Troi" de Santiago de Cuba. Esta prueba fue aceptada por los expertos, pues sirvió como herramienta para la exploración de los mecanismos perceptivos en tareas de detección y discriminación de las propiedades del movimiento. Además, de acuerdo con el alfa de Cronbach, los valores en la consistencia interna y estabilidad fueron aceptables. Se concluyó que este test puede contribuir al estudio de los mecanismos de la percepción visual.

An analytic and prospective investigation was carried out to validate the visual exploration test of movement perception by means of the expert method, as well as to determine its reliability and internal consistency based on Cronbach´s alpha, from June, 2013 to the same period of 2014. Its implementation included an initial pilotage to achieve homogeneity, and in the second stage 144 children between 9-11 years were selected, belonging to "Nguyen Van Troi" Primary School in Santiago de Cuba. This test was accepted by the experts, as it became a tool for the exploration of the perceptive mechanisms in detecting tasks and discriminating the movement properties. Also, according to Cronbach´s alpha, the values in the internal consistency and stability were acceptable. It was concluded that this test can contribute to the study of the mechanisms of visual perception.