Is quantitative diffusion-weighted MRI a reliable method in the assessment of the inflammatory activity in ulcerative colitis?
OBJECTIVE
We investigated the relationship between the apparent diffusion coefficient (ADC) values of the colonic wall and the pathologic pericolonic lymph nodes (PCLNs) and inflammatory activity in ulcerative colitis patients by diffusion-weighted magnetic resonance imaging (DW-MRI).


METHODS
A total of 28 ulcerative colitis patients (9 endoscopically active, 10 subacute and 9 in remission) were evaluated by DW-MRI with 0, 500 and 1000 s/mm² b-values. The ADC values of the rectum and sigmoid colon walls and the adjacent PCLNs were obtained for quantitative analysis. The DW-MRI findings were compared to the disease activity.


RESULTS
The ADC values of the sigmoid colon were similar in patients with active, subacute and remissive ulcerative colitis (P = 0.472). The ADC values of the rectum were different (P = 0.009) between patients in the active (1.08 ± 0.14×10⁻³ mm²/s) and subacute phases (1.13 ± 0.23×10⁻³ mm²/s) of disease and those in remission (1.29 ± 0.17×10⁻³ mm²/s). The ADC values of the PCLNs (P = 0.899) did not differ with respect to disease activity.


CONCLUSIONS
DW-MRI is useful in identifying disease activity in ulcerative colitis patients, especially with respect to the rectum. The ADC values of the rectum increase during remission and decrease in patients with active distal colitis. The ADC values of the PCLNs were not useful in determining disease activity.
Kılıçkesmez
Ozgür
O
Department of Radiology, Yeditepe University School of Medicine, İstanbul, Turkey. okilickesmez@yahoo.com
Soylu
Aliye
A
Yaşar
Nurgül
N
Demirbaş
Tuna
T
Dolapçıoğlu
Can
C
Poturoğlu
Sule
S
Sevindir
Isa
I
Cimilli
Tan
T
D000328:Adult; D003093:Colitis, Ulcerative / Q000150:complications / Q000473:pathology*; D012809:Colon, Sigmoid / Q000473:pathology; D003287:Contrast Media; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D019786:Gadolinium DTPA; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D007249:Inflammation / Q000150:complications / Q000473:pathology*; D008198:Lymph Nodes / Q000473:pathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012007:Rectum / Q000473:pathology; D015203:Reproducibility of Results
D003287:Contrast Media; D019786:Gadolinium DTPA