Sang Hyun Choi1, Kyung Won Kim, Ja Youn Lee, Kyung-Jo Kim, Seong Ho Park. 1. *Department of Radiology and the Research Institute of Radiology, Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, South Korea; †National Evidence-based Healthcare Collaborating Agency, Jung-gu, South Korea; and ‡Department of Gastroenterology, Asan Medical Center, University of Ulsan College of Medicine, Songpa-gu, South Korea.
Abstract
BACKGROUND: To systematically determine the performance of diffusion-weighted imaging magnetic resonance enterography (DWI-MRE) for evaluating bowel inflammation in Crohn's disease and sources of heterogeneity between reported results. METHODS: We identified research studies that investigated DWI-MRE to diagnose bowel inflammation (present versus absent) or to assess bowel inflammatory severity in Crohn's disease by performing a systematic search of PubMed MEDLINE and EMBASE (until March 31, 2015). Study quality was assessed using QUADAS-2. For studies reporting dichotomous diagnosis of bowel inflammation, study heterogeneity and threshold effect were analyzed, summary sensitivity and specificity were estimated, and meta-regression analysis was performed to further explore study heterogeneity. For studies reporting assessment of inflammatory severity, a qualitative summary was performed. RESULTS: Of 159 articles screened, we found 12 studies (1515 bowel segments) reporting a diagnosis of bowel inflammation and 6 studies (1066 bowel segments) reporting assessment of inflammatory severity. The summary sensitivity and specificity were 92.9% (95% CI, 85.8%-96.6%; I = 87.9%) and 91% (95% CI, 79.7%-96.3%; I = 95.1%), respectively. Sensitivity and false-positive rate were inversely correlated (r = -0.650; P = 0.022). Lack of blinding to contrast-enhanced MRE when interpreting DWI-MRE (P = 0.01) and use of contrast-enhanced MRE as a reference standard (P < 0.01) in some studies were significant factors for study heterogeneity and likely caused overestimation of DWI-MRE accuracy. There was rather clear correlation between diffusion-related parameters and bowel inflammation severity, although the strengths were heterogeneous (correlation coefficient, 0.39-0.98). CONCLUSIONS: DWI-MRE accuracy was very heterogeneous between studies and was likely overestimated in some studies. Despite rather clear correlation between diffusion-related parameters and bowel inflammatory severity, its strength was variable.
BACKGROUND: To systematically determine the performance of diffusion-weighted imaging magnetic resonance enterography (DWI-MRE) for evaluating bowel inflammation in Crohn's disease and sources of heterogeneity between reported results. METHODS: We identified research studies that investigated DWI-MRE to diagnose bowel inflammation (present versus absent) or to assess bowel inflammatory severity in Crohn's disease by performing a systematic search of PubMed MEDLINE and EMBASE (until March 31, 2015). Study quality was assessed using QUADAS-2. For studies reporting dichotomous diagnosis of bowel inflammation, study heterogeneity and threshold effect were analyzed, summary sensitivity and specificity were estimated, and meta-regression analysis was performed to further explore study heterogeneity. For studies reporting assessment of inflammatory severity, a qualitative summary was performed. RESULTS: Of 159 articles screened, we found 12 studies (1515 bowel segments) reporting a diagnosis of bowel inflammation and 6 studies (1066 bowel segments) reporting assessment of inflammatory severity. The summary sensitivity and specificity were 92.9% (95% CI, 85.8%-96.6%; I = 87.9%) and 91% (95% CI, 79.7%-96.3%; I = 95.1%), respectively. Sensitivity and false-positive rate were inversely correlated (r = -0.650; P = 0.022). Lack of blinding to contrast-enhanced MRE when interpreting DWI-MRE (P = 0.01) and use of contrast-enhanced MRE as a reference standard (P < 0.01) in some studies were significant factors for study heterogeneity and likely caused overestimation of DWI-MRE accuracy. There was rather clear correlation between diffusion-related parameters and bowel inflammation severity, although the strengths were heterogeneous (correlation coefficient, 0.39-0.98). CONCLUSIONS: DWI-MRE accuracy was very heterogeneous between studies and was likely overestimated in some studies. Despite rather clear correlation between diffusion-related parameters and bowel inflammatory severity, its strength was variable.
Authors: Saurabh Kedia; Raju Sharma; Govind K Makharia; Vineet Ahuja; Devendra Desai; Devasenathipathy Kandasamy; Anu Eapen; Karthik Ganesan; Uday C Ghoshal; Naveen Kalra; D Karthikeyan; Kumble Seetharama Madhusudhan; Mathew Philip; Amarender Singh Puri; Sunil Puri; Saroj K Sinha; Rupa Banerjee; Shobna Bhatia; Naresh Bhat; Sunil Dadhich; G K Dhali; B D Goswami; S K Issar; V Jayanthi; S P Misra; Sandeep Nijhawan; Pankaj Puri; Avik Sarkar; S P Singh; Anshu Srivastava; Philip Abraham; B S Ramakrishna Journal: Indian J Gastroenterol Date: 2018-01-06