Use of the time–signal intensity curve from dynamic magnetic resonance imaging to evaluate remnant pancreatic fibrosis after pancreaticojejunostomy in patients undergoing pancreaticoduodenectomy

Abstract

The TIC obtained from dynamic MRI is a reliable indicator of fibrosis in the remnant pancreas after pancreaticoduodenectomy. Use of a DMA was associated with a lower risk of pancreatic fibrosis 1-3 years after surgery than a PJSA.

Decreased Blood Flow with Increased Metabolic Activity: A Novel Sign of Pancreatic Tumor Aggressiveness

“…Park et al (25) observed that high perfusion in pancreatic cancer detected on DCE-CT was associated with increased response to chemoradiotherapy. Also, the role of DCE magnetic resonance imaging has evolved in the field of perfusion imaging, and several groups have used it in evaluating the perfusion of benign and malignant pancreatic lesions (10,(26)(27)(28). Nevertheless, [ 15 O]H 2 O PET has been studied more extensively than either DCE-CT or magnetic resonance imaging, and is regarded by some authors as a gold standard in perfusion imaging (15).…”

Temporal assessment of pancreatic blood flow and perfusion following secretin stimulation using noninvasive MRI

“…Dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) has been used to assess pancreatic blood flow in healthy volunteers and patients. However, this technique requires the injection of a gadolinium-based contrast agent from which the first pass is measured and quantified for perfusion, 7,8 which again limits repeat measures. Arterial spin labeling (ASL) has been used previously to measure perfusion in the pancreas 9,10 as well as several other abdominal organs [11][12][13] without administration of contrast agent, thus allowing for repeated measures and enables the assessment of temporal changes in pancreatic perfusion, without the risks associated with intravenous contrast agents.…”

Preoperative imaging evaluation of pancreatic pathologies for the objective prediction of pancreatic fistula after pancreaticoduodenectomy

“…The pancreatic TICs were calculated and plotted as the percentage increase in the SI of the pancreas, according to the enhancement formula (SI post − SI pre )/SI pre × 100, where SI pre and SI post represent the pre-and post-contrast (25 s, and 1, 2, and 3 min after a rapid bolus injection of contrast) SIs of the pancreas obtained from dynamic contrast-enhanced T1-weighted MRI, respectively. The pancreatic TICs can be categorized into three types; type I shows a rapid rise to a peak, followed by a rapid decline, and types II and III show a slow rise to a peak, followed by a slow decline or a plateau [46]. In patients who underwent PD, the pancreatic TIC analyses yielded several findings.…”

“…Dynamic MRI-based perfusion characteristics of the pancreas displayed as the time-signal intensity curve (TIC) have enabled the precise assessment of the histological degree of pancreatic fibrosis in association with the occurrence of POPF after PD [18,46]. The pancreatic TICs were calculated and plotted as the percentage increase in the SI of the pancreas, according to the enhancement formula (SI post − SI pre )/SI pre × 100, where SI pre and SI post represent the pre-and post-contrast (25 s, and 1, 2, and 3 min after a rapid bolus injection of contrast) SIs of the pancreas obtained from dynamic contrast-enhanced T1-weighted MRI, respectively.…”

“…The ability of MRI to assess pancreatic fibrosis has been demonstrated in several studies, on the basis of a comparison between MRI findings and histological evidence of fibrosis [43][44][45][46][47] Watanabe et al [43] reported that the pancreas-to-muscle signal intensity (SI) ratios on unenhanced T1-weighted MRI and the apparent diffusion coefficient (ADC) values of the pancreas on diffusion-weighted MRI were independently associated with the histological grade of pancreatic fibrosis and the expression of activated pancreatic stellate cells in a multivariate regression analysis of 29 patients who underwent pancreatectomy. They concluded that the mean pancreas-to-muscle SI ratio on T1-weighted MRI images may be a potential biomarker for predicting POPF after pancreatic resection, as this ratio was significantly higher for patients who developed POPF (1.6 ± 0.2) than for those without POPF (1.2 ± 0.2; p = 0.0029), with an odds ratio of 21.3 for POPF in patients with an SI ratio of ≥1.41.…”