Meniscal tears: comparison of the conventional spin-echo and fast spin-echo techniques through image processing

Background: Conventional spin-echo (PD-CSE) and fast spin-echo (PD-FSE) techniques are frequently used to detect meniscal tears. However, the time delay for imaging with PD-CSE has resulted in its replacement with faster techniques, such as proton density fast spin-echo (PD-FSE), which has become a frequent tool at most diagnostic centres. Qualitative analysis shows that the PD-CSE technique is more sensitive, but other authors have not found significant differences between the aforementioned techniques. Therefore, we performed a quantitative analysis in this study that aims to measure differences in the quality of the images obtained with both techniques.Methods: We compared the PD-CSE and PD-FSE techniques by quantitatively analysing the obtained proton density images: the area shown, as well as the brightness and lesion contrast of the obtained image. A set of 100 images from 50 patients thought to contain meniscal tears of the knee were selected. These 100 images were obtained from all individuals using both the PD-CSE and PD-FSE techniques. the images were processed using software developed in Delphi. in addition to these quantifications, three physicians, who are specialists in radiology and capable of analysing magnetic resonance (MR) images of the musculoskeletal system, qualitatively analysed the diagnostic sensitivity of both techniques.Results: On average, samples obtained via the PD-CSE technique contained 22% more pixels in the lesion area. the contrast differed by 28%, and the brightness differed by 31%. the two techniques were correlated using Student's t-test, which showed a statistically significant difference. the specialists detected meniscal tears in 30 of the images obtained via the PD-CSE technique, while only 72% of these cases were detected via the PD-FSE technique.Conclusions: the PD-CSE technique was shown to be superior to PD-FSE for all of the evaluated properties, making its selection preferable.FAEP (Fundacao de Amparo a Ensino e Pesquisa) from Universidade de Mogi das CruzesUniv Mogi das Cruzes, Nucleo Pesquisas Tecnol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Diagnost Imagem EPM, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Diagnost Imagem EPM, São Paulo, BrazilWeb of Scienc

Value-based Design of Industrial Services: The Impact of Lean Management

Background: Magnetic resonance (MR) techniques used to detect lesions of the ligament complex for articulation of the ankle lack the desired accuracy for the study of the calcaneofibular ligament (CFL). the lack of sensitivity of the conventional techniques is due to variations in the dimensions of the CFL. the best results are obtained when the image plane is oriented parallel to the ligament. This study aims to develop a model that addresses the width, length and angle parameters of the CFL and the orientation of the MR image plane, and thus determine a technique in the oblique transversal plane with the foot in anatomical flexion, that is adequate for the majority of patients.Method: To determine this orientation and adapt it to the majority of people, images of the articulation of the ankle in the 3D isotropic, volumetric, sagittal plane of 100 volunteers were taken using the MR technique. None of the volunteers had a clinical history of ligament lesions, serious pathologies, or surgeries. A measurement of the length, width, and angle of the CFL relative to the sole of the foot was performed using the MR tools. A virtual model was developed that simulated the visualization of the CFL in the oblique transversal image plane from 35 degrees to 45 degrees using the CFL dimensions of 100 volunteers. the comparison of the simulations with the reconstructed images validated the model and permitted the calculation of the agreement and sensitivity of each technique in the detection of the complete CFL.Results: Using the simulator, it was possible to obtain the limit angle for complete CFL visualization as a function of its dimensions for any angle of the oblique transversal image plane of the MR.Conclusion: the results suggest that a single image acquisition technique in the oblique transversal plane at 38 degrees with the foot in anatomical flexion would serve the majority of patients