Comparison of T-1-weighted Spin-Echo and 3D T-1-weighted multishot echo planar pulse sequences in imaging the brain at 1T

The purpose of this study was to evaluate the ability of three dimensional T-1-weighted multi-shot Echo Planar Imaging (3D T(1)w EPI) MR pulse sequenc e to provide comparable to T(1)w Spin Echo (SE) results in various diseases of the brain, during shorter acquisition times, Thirty-six patients (aged 30-74 years) with various indications were included in the study. All exami nations were performed with a 1T MR scanner with a maximum gradient strengt h of 15 mT/m, The SE sequence lasted 3 min 50s and the 3D T(1)w EPI 59s, Th e quantitative analysis included number of enhancing lesions, signal-to-noi se ratio of the enhancing lesions and contrast-to-noise ratio (CNR) between enhancing lesions and white matter in both sequences before and after i.v. administration of 0.1 mmol/kg gadopentetate dimeglumine. In addition, the percentage increase of enhancement was measured in each lesion of each sequ ence. The qualitative analysis included a) conspicuity of the lesions and b ) presence of artifacts. The T(1)w SE sequence was significantly better com pared to 3D T(1)w EPI in all quantitative measurements with the exception o f CNR of enhancing lesions before contrast administration and the percentag e enhancement. The conspicuity of the lesions did not differ between the tw o sequences. The EPI sequence presented with significantly more artifacts. We conclude that the 3D T(1)w EPI sequence could not be used instead of the conventional T(1)w SE, in routine imaging of the brain. Its overall diagno stic capability, could be useful only in uncooperative patients. (C) 1999 E lsevier Science Inc.