ª Springer Science+Business Media New York 2014
Abdominal Imaging
Abdom Imaging (2014) DOI: 10.1007/s00261-014-0247-1
Quantitative apparent diffusion coefficient (ADC) values as an imaging biomarker for fibrosis in pediatric Crohn’s disease: preliminary experience A. Kovanlikaya,1 D. Beneck,2 M. Rose,3 P. Renjen,1 A. Dunning,4 A. Solomon,3 R. Sockolow,3 P. W. Brill1 1
Department of Radiology, Weill Cornell Medical College, New York Presbyterian Hospital, 525 E 68th St., New York, NY 1006, USA 2 Department of Pathology, Weill Cornell Medical College, New York Presbyterian Hospital, 525 E 68th St., New York, NY 1006, USA 3 Division of Gastroenterology, Department of Pediatrics, Weill Cornell Medical College, New York Presbyterian Hospital, 525 E 68th St., New York, NY 1006, USA 4 Duke Clinical Research Institute, 2400 Pratt St, Durham, NC 27705, USA
Abstract Purpose: To compare histopathology with ADC values in strictured bowel segments in pediatric patients with known Crohn’s disease and surgical bowel resection. Methods: Magnetic resonance enterography (MRE) images of 14 subjects with Crohn’s disease who had surgical bowel resection for strictures were retrospectively reviewed. Five of 14 subjects had DWI (b=0, 500, 1000) sequences included in the MRE study. ADC measurements were made by placing ROI’s in the strictured bowel wall and compared to full-thickness histologic analysis of resected specimens. ADC values were also compared to control ADC measurements (in normal and inflamed-nonstenotic bowel segments) as well as the mean ADC values of Crohn’s patients published in the literature. Results: All five subjects had transmural fibrosis. The mean ADC value with b = 500 was 0.92 ± 0.10 9 10-3 mm2/s and with b = 1000 was 0.8 ± 0.05 9 10-3 mm2/s. There was a significant difference in ADC values between strictures and inflamed-nonstenotic segments (p=0.0143) and between normal and diseased bowel segments (p=0.009–0.0143). Conclusions: Quantitative ADC measures of transmural fibrosis are lower compared to the reported values of
Correspondence to: A. Kovanlikaya; email: [email protected]
inflammation in Crohn’s disease. To our knowledge, this is the first pediatric pilot study to investigate the correlation of quantitative DWI with histology of surgical specimens in pediatric patients with Crohn’s disease. Our results are comparable to a recently published study in adult Crohn’s patients showing a significant correlation between a decrease in ADC values and fibrosis Key words: Crohn—MR enterography— DWI—ADC—Fibrosis
The modern concept of Crohn’s disease emphasizes the progressive nature of the disease from inflammation to fibrosis manifesting as disease complications such as stricture. It is widely accepted that stricture formation, given the transmural nature of the disease, affects all layers of the bowel wall. However, no histological scoring system has yet been developed for grading fibrosis [1]. The majority of prior studies examining imaging evaluation of Crohn’s disease focus on detecting active disease [2–5]. However, accurate imaging detection of mural fibrosis is just as important, not only because it is refractory to medical therapy [2], but also because it is an indication for mechanical therapy via endoscopy or surgery.
A. Kovanlikaya et al.: Quantitative ADC values in pediatric Crohn’s disease
Currently, in vivo detection of bowel wall fibrosis in humans by cross-sectional imaging is limited [1]. Magnetization transfer imaging and ultrasound elastography has recently been used to detect fibrosis in animal models of Crohn’s disease and ex vivo resected stenotic human bowel segments [6–8]. As clinicians begin to think more in terms of disease progression, imaging has to include information that reflects pathologic tissue processes like fibrosis. Differentiating active disease and fibrosis is needed in clinical practice which can probably only be done with quantitative analysis.The use of quantitative diffusion-weighted imaging (DWI) for the detection of bowel wall inflammation has been described [4, 5, 9]. Previous magnetic resonance imaging (MRI) studies in adults have reported ADC values for inflamed bowel ranging between 1.4–1.98 9 10-3 mm2/s and for normal bowel ranging between 2.56–3.11 9 10-3 mm2/s [3, 4]. However, complete quantitative assessment of Crohn’s disease can only be performed on the basis of fullthickness evaluation of surgical specimens. Three studies in adults and one study in children have used surgical specimens as a reference standard for correlation with conventional MR parameters [2, 10–12]. Only one recent adult study has correlated quantitative DWI with a histopathological reference standard [13]. The purpose of this study was to quantitatively assess the correlation of quantitative DWI with histology of resected bowel strictures in children with Crohn’s disease.
Materials and methods This retrospective analysis was approved by the Institutional Review Board.
Patient selection Magnetic resonance enterography (MRE) images of 14 pediatric subjects (
Abdominal Imaging
Abdom Imaging (2014) DOI: 10.1007/s00261-014-0247-1
Quantitative apparent diffusion coefficient (ADC) values as an imaging biomarker for fibrosis in pediatric Crohn’s disease: preliminary experience A. Kovanlikaya,1 D. Beneck,2 M. Rose,3 P. Renjen,1 A. Dunning,4 A. Solomon,3 R. Sockolow,3 P. W. Brill1 1
Department of Radiology, Weill Cornell Medical College, New York Presbyterian Hospital, 525 E 68th St., New York, NY 1006, USA 2 Department of Pathology, Weill Cornell Medical College, New York Presbyterian Hospital, 525 E 68th St., New York, NY 1006, USA 3 Division of Gastroenterology, Department of Pediatrics, Weill Cornell Medical College, New York Presbyterian Hospital, 525 E 68th St., New York, NY 1006, USA 4 Duke Clinical Research Institute, 2400 Pratt St, Durham, NC 27705, USA
Abstract Purpose: To compare histopathology with ADC values in strictured bowel segments in pediatric patients with known Crohn’s disease and surgical bowel resection. Methods: Magnetic resonance enterography (MRE) images of 14 subjects with Crohn’s disease who had surgical bowel resection for strictures were retrospectively reviewed. Five of 14 subjects had DWI (b=0, 500, 1000) sequences included in the MRE study. ADC measurements were made by placing ROI’s in the strictured bowel wall and compared to full-thickness histologic analysis of resected specimens. ADC values were also compared to control ADC measurements (in normal and inflamed-nonstenotic bowel segments) as well as the mean ADC values of Crohn’s patients published in the literature. Results: All five subjects had transmural fibrosis. The mean ADC value with b = 500 was 0.92 ± 0.10 9 10-3 mm2/s and with b = 1000 was 0.8 ± 0.05 9 10-3 mm2/s. There was a significant difference in ADC values between strictures and inflamed-nonstenotic segments (p=0.0143) and between normal and diseased bowel segments (p=0.009–0.0143). Conclusions: Quantitative ADC measures of transmural fibrosis are lower compared to the reported values of
Correspondence to: A. Kovanlikaya; email: [email protected]
inflammation in Crohn’s disease. To our knowledge, this is the first pediatric pilot study to investigate the correlation of quantitative DWI with histology of surgical specimens in pediatric patients with Crohn’s disease. Our results are comparable to a recently published study in adult Crohn’s patients showing a significant correlation between a decrease in ADC values and fibrosis Key words: Crohn—MR enterography— DWI—ADC—Fibrosis
The modern concept of Crohn’s disease emphasizes the progressive nature of the disease from inflammation to fibrosis manifesting as disease complications such as stricture. It is widely accepted that stricture formation, given the transmural nature of the disease, affects all layers of the bowel wall. However, no histological scoring system has yet been developed for grading fibrosis [1]. The majority of prior studies examining imaging evaluation of Crohn’s disease focus on detecting active disease [2–5]. However, accurate imaging detection of mural fibrosis is just as important, not only because it is refractory to medical therapy [2], but also because it is an indication for mechanical therapy via endoscopy or surgery.
A. Kovanlikaya et al.: Quantitative ADC values in pediatric Crohn’s disease
Currently, in vivo detection of bowel wall fibrosis in humans by cross-sectional imaging is limited [1]. Magnetization transfer imaging and ultrasound elastography has recently been used to detect fibrosis in animal models of Crohn’s disease and ex vivo resected stenotic human bowel segments [6–8]. As clinicians begin to think more in terms of disease progression, imaging has to include information that reflects pathologic tissue processes like fibrosis. Differentiating active disease and fibrosis is needed in clinical practice which can probably only be done with quantitative analysis.The use of quantitative diffusion-weighted imaging (DWI) for the detection of bowel wall inflammation has been described [4, 5, 9]. Previous magnetic resonance imaging (MRI) studies in adults have reported ADC values for inflamed bowel ranging between 1.4–1.98 9 10-3 mm2/s and for normal bowel ranging between 2.56–3.11 9 10-3 mm2/s [3, 4]. However, complete quantitative assessment of Crohn’s disease can only be performed on the basis of fullthickness evaluation of surgical specimens. Three studies in adults and one study in children have used surgical specimens as a reference standard for correlation with conventional MR parameters [2, 10–12]. Only one recent adult study has correlated quantitative DWI with a histopathological reference standard [13]. The purpose of this study was to quantitatively assess the correlation of quantitative DWI with histology of resected bowel strictures in children with Crohn’s disease.
Materials and methods This retrospective analysis was approved by the Institutional Review Board.
Patient selection Magnetic resonance enterography (MRE) images of 14 pediatric subjects (
