Clarity of Anatomic Information: Comparison of Variations in Combination of Time Repetition (TR) and Echo Train Length (ETL) MRI Lumbar Sequence T2W Turbo Spin Echo in the Diagnosis of Low Back Pain

Abstract

— Time Repetition (TR) and Echo Train Length (ETL) are the parameters in MRI that can be adjusted by a radiographer to affect image quality, anatomic information, and scan time. There are various TR and ETL adjustments used for lumbar MR imaging. This study is to determine the differences in the combination of TR and ETL to the anatomic information of the images. This is an experimental research. Data were collected from 30 patients with variations of TR 1000 , TR 2000 , ETL 13 , ETL 17 , and ETL 21 . The Images were evaluated by radiologists. Evaluation of the images were conducted on the corpus vertebrae, inter vertebral disc, conus medullar, cerebrospinal fluid and ligamentum flavum. The data were analyzed using Friedman test with 95% CI. The results show that the combination of TR and ETL variations affect the anatomic information of T2WI TSE sagittal lumbar MRI. The Friedman test shows differences of image anatomic information from variations of the combination of TR and ETL (p-value = 0.001). The Combination of TR 2000 ETL 17 produces optimal image information.