Akisik M Fatih, Aisen Alex M, Sandrasegaran Kumar, Jennings S Gregory, Lin Chen, Sherman Stuart, Lin John A, Rydberg Magnus
Department of Radiology, Indiana University School of Medicine, 550 N University Blvd, Indianapolis, IN 46202, USA.
Radiology. 2009 Jan;250(1):103-9. doi: 10.1148/radiol.2493080160. Epub 2008 Nov 10.
To retrospectively measure and compare changes in pancreatic apparent diffusion coefficient (ADC) following secretin administration in patients with and those without chronic pancreatitis (CP) who underwent magnetic resonance (MR) cholangiopancreatography with diffusion-weighted (DW) imaging.
This retrospective HIPAA-compliant study was approved by the authors' institutional review board, with waiver of informed consent. Eighty-nine patients were categorized by the referring gastroenterologist as having no CP (n = 37), mild CP (n = 33), or severe CP (n = 19) on the basis of Cambridge criteria and/or clinical course. Mean age was 52.2 years (range, 21-82 years) in women and 54.3 years (range, 32-81 years) in men. Patients underwent 1.5-T MR cholangiopancreatography, including DW sequences (b = 0, 100, and 400 sec/mm(2)) performed serially for 10 minutes after secretin injection. Severity level of CP was analyzed for sex (Fisher exact test) and age (analysis of variance) differences. Pairwise comparisons of mean ADCs for each parameter (no CP vs mild CP, no CP vs severe CP, mild CP vs severe CP) were performed (Mann-Whitney test). Threshold values of non-secretin-enhanced ADC for pancreatitis discrimination were calculated with receiver operating characteristic analysis. P < .05 was considered to show a significant difference.
Patients with severe CP were more likely to be men than were those without pancreatitis; there were no significant age differences between groups. Mean nonenhanced and maximum secretin-enhanced ADCs were higher in patients without CP than in those with mild or severe CP but did not vary between those with mild and severe CP. Percentage increase in ADC after secretin injection and time to peak ADC did not vary among groups. An ADC of less than 179 x 10(-5) mm(2)/sec was optimal for delineating normal pancreas from CP groups.
In symptomatic patients, baseline pancreatic ADC obtained with DW imaging prior to secretin administration may aid in diagnosis of CP and assessment of its severity; ADC response to secretin administration may be less useful.
回顾性测量并比较在接受磁共振（MR）胰胆管造影及扩散加权（DW）成像检查的慢性胰腺炎（CP）患者和非CP患者中，注射胰泌素后胰腺表观扩散系数（ADC）的变化。
这项符合健康保险流通与责任法案（HIPAA）的回顾性研究经作者所在机构审查委员会批准，无需知情同意书。根据剑桥标准和/或临床病程，89例患者被转诊的胃肠病学家分为无CP组（n = 37）、轻度CP组（n = 33）或重度CP组（n = 19）。女性平均年龄为52.2岁（范围21 - 82岁），男性平均年龄为54.3岁（范围32 - 81岁）。患者接受1.5-T MR胰胆管造影检查，包括在注射胰泌素后连续10分钟进行的DW序列（b = 0、100和400 sec/mm²）。分析CP严重程度在性别（Fisher精确检验）和年龄（方差分析）方面的差异。对每个参数的平均ADC进行两两比较（无CP组与轻度CP组、无CP组与重度CP组、轻度CP组与重度CP组）（Mann-Whitney检验）。通过受试者操作特征分析计算用于鉴别胰腺炎的非胰泌素增强ADC阈值。P < 0.05被认为具有显著差异。
重度CP患者中男性比无胰腺炎患者更常见；各组之间年龄无显著差异。无CP患者的平均非增强和最大胰泌素增强ADC高于轻度或重度CP患者，但轻度和重度CP患者之间无差异。注射胰泌素后ADC的百分比增加和ADC峰值时间在各组之间无差异。ADC小于179×10⁻⁵ mm²/sec最适合区分正常胰腺与CP组。
对于有症状的患者，在注射胰泌素前通过DW成像获得的基线胰腺ADC可能有助于CP的诊断及其严重程度的评估；胰泌素注射后ADC的反应可能用处较小。
