Patient
28 subjects (M/F 20/8,
mean age 45,
age range 26-82) were evaluated,
from March to November 2010,
with abdominal MR-DwI:
- 7 healthy volunteers
- 7 subjects with chronic liver disease F0-F2 (METAVIR score)
- 7 F3-F4 Child A
- 7 F4 Child BC
classified as group I-II-III-IV,
respectively.
The inclusion criteria for the healthy subject for this study were as follows: absence and negative anamnesis for drug and alcohol abuse,
no current medication,
normal appearance of the liver on ultrasound study (no focal/diffuse liver disease),
negative anamnesis for viral hepatitis (negative viral hepatitis serologic markers and liver function tests within normal limits) and abdominal surgery.
All the young and middle age healthy volunteers were resident or colleagues.
Everyone had blood test performed by Radioprotection Department during surveillance medical examination.
Imaging
All examinations were carried out using a 1.5 Tesla (T) unit (Gyroscan ACS NT Intera Release 12,
Philips,
Eindhoven,
The Netherlands) equipped with a four- channel phased array multicoil,
adequately positioned to cover the upper abdomen of the subject lying in a supine position,
the arms extended over the head to avoid artifacts.
The scanner provides a maximum gradient strength of 30 mT/m,
with a peak slew rate of 120 mT/m/ms.
The protocol included the two following DwI acquisitions:
echo planar imaging (EPI) single-shot,
breath-hold (b 0-150 s/mm2 and 0-1000 s/mm2),
and free-breath (multi-b=0-200-400-600-800-1000 s/mm2), TR/TE = 1949/46 e 2438/70 ms respectively,
EPI factor = 65,
slice thickness/number = 9 mm/12,
gap = 1 mm,
flip angle = 90°,
SENSE 2,
FOV = 300– 420 mm,
NSA = 2,
acquisition time = 20 s,
half scan factor 62%,
bandwidth 1535 Hz,
RFOV 70%,
phase scan percentage 74%,
acquisition voxel (mm3) 3.32/4.50/9.00,
reconstruction voxel (mm3) 1.33/1.33/9.00.
Phantom
The reliability of our scanner has been validated by a phantom study [1].
Image analyses and statistic study
Two observers,
double-blind control procedure,
have estimated ADC,
D,
and f applying a region of interest (ROI) in 4 out of 12 sections in the middle-lower portion of the right hepatic lobe.
For each group were calculated mean,
SD and limits of agreement at 95% of the parameters D,
f (ADC maps = 150 and 1000 s/mm2) considering the only breath-hold acquisitions. To determine significant differences between means in different groups, ANOVA test was performed.
Statistical analysis was performed with SPSS software (release 17.0.0, SPSS Inc., Chicago, Illinois,
USA).