Apparent diffusion coefficient of line scan diffusion image in normal prostate and prostate cancer—comparison with single-shot echo planner image

✍ Scribed by Takeshi Yoshizako; Akihiko Wada; Koji Uchida; Shinji Hara; Mikio Igawa; Hajime Kitagaki; Stephan E. Maier

• Publisher: Elsevier Science
• Year: 2011
• Tongue: English
• Weight: 370 KB
• Volume: 29
• Category: Article
• ISSN: 0730-725X
• DOI: 10.1016/j.mri.2010.07.013

✦ Synopsis

Purpose:

This retrospective study was designed to evaluate the apparent diffusion coefficient (adc) of line scan diffusion images (lsdi) in normal prostate and prostate cancer. single-shot echo planner images (ss-epi) were used for comparison.

Materials and methods:

Twenty prostate tumors were examined by conventional mri in 14 patients prior to radical prostatectomy. all patients were examined with a 1.5-t mr imager (signa cv/i ver. 9.1 ge medical system milwaukee, wi, usa). diffusion-weighted mr imaging (dwi) using lsdi was performed with a pelvic phased-array coil, with b values of 5 and 800 s/mm². dwi using ss-epi was performed with a body coil, with b values of 0 and 800 s/mm². the adcs of each sequence for 14 normal prostate and 20 prostate cancers were histopathologically assessed. signal-to-noise ratio (snr) on dwi was estimated and compared for each sequence.

Results:

The mean adcs (±s.d.) of normal peripheral zones (pz), transition zones (tz) and cancer (in 10⁻³ mm²/s) that used lsdi were 1.42±0.12, 1.23±0.10 and 0.79±0.19, respectively. those that used ss-epi were 1.76±0.26, 1.38±0.20 and 1.05±0.27, respectively. using unpaired t test (p<.05), we found a significant difference in each sequence between normal tissue (both pz and tz) and the cancer. paired t test (p<.05) also registered a significant difference between lsdi and ss-epi. mean snr for dwi using lsdi was 16.49±5.03, while the dwi using ss-epi was 18.85±9.26. the difference between the snr of each sequence was not statistically significant by paired t test.

Conclusion:

We found that adcs using lsdi and ss-epi showed similar tendencies in the same patients. however, in all regions, lsdi adcs had smaller standard deviations than ss-epi adcs.