Relevance of dynamic studies with magnetic resonance enterography in Crohn's disease.

INTRODUCTION: A proper quantification of the inflammatory activity in Crohn's disease (CD) lesions is needed to establish the appropriate management for each patient. The aim of this study is to evaluate the inflammatory activity of affected segments in small bowel lesions using dynamic studies of magnetic resonance enterography (MRE) in patients undergoing surgery, and their correlation with the level of inflammation and histological fibrosis of the surgical piece. METHODS: A prospective, consecutive, observational, clinical study was conducted that included all the patients with small bowel CD that underwent surgery in this center between March 2011 and September 2013. Diagnosis was established according to Lennard-Jones criteria and the Montreal classification. All the patients underwent MRE within three months before surgery, using a routine protocol involving Liver Acquisition with Volume Acceleration-Extended Volume (LAVA-XV) sequence for the dynamic studies before intravenous administering of gadolinium and 30, 70, 120, and 420s after administering this. The results allowed the designing of graphics with different uptake patterns. The Chiorean classification was used in the histological analysis, as well as a modified version published previously by this study group. RESULTS: A total of 28 patients with 47 lesions were analyzed. There was a significant correlation between both curve patterns, including the modified Chiorean classification (P<0.0001) as well as the level of inflammation (P<0.0001) and fibrosis (P<0.002). Inflammatory patterns of dynamic studies are related to histological findings with 80.9% accuracy (sensitivity=75.7%; specificity=100%). CONCLUSION: There is a high correlation between dynamic enhancement studies and the level of inflammatory activity. MRE is a suitable tool to differentiate between inflammatory and fibrotic lesions, making it useful to decide the appropriate management of each patient.

Relevance of dynamic studies with magnetic resonance enterography in Crohn's disease / Relevancia de los estudios dinámicos en Resonancia Entérica en la Enfermedad de Crohn

INTRODUCTION: A proper quantification of the inflammatory activity in Crohn's disease (CD) lesions is needed to establish the appropriate management for each patient. The aim of this study is to evaluate the inflammatory activity of affected segments in small bowel lesions using dynamic studies of magnetic resonance enterography (MRE) in patients undergoing surgery, and their correlation with the level of inflammation and histological fibrosis of the surgical piece. METHODS: A prospective, consecutive, observational, clinical study was conducted that included all the patients with small bowel CD that underwent surgery in this center between March 2011 and September 2013. Diagnosis was established according to Lennard-Jones criteria and the Montreal classification. All the patients underwent MRE within three months before surgery, using a routine protocol involving Liver Acquisition with Volume Acceleration-Extended Volume (LAVA-XV) sequence for the dynamic studies before intravenous administering of gadolinium and 30, 70, 120, and 420s after administering this. The results allowed the designing of graphics with different uptake patterns. The Chiorean classification was used in the histological analysis, as well as a modified version published previously by this study group. RESULTS: A total of 28 patients with 47 lesions were analyzed. There was a significant correlation between both curve patterns, including the modified Chiorean classification (p < 0.0001) as well as the level of inflammation (p < 0.0001) and fibrosis (p < 0.002). Inflammatory patterns of dynamic studies are related to histological findings with 80.9% accuracy (sensitivity=75.7%; specificity=100%). CONCLUSION: There is a high correlation between dynamic enhancement studies and the level of inflammatory activity. MRE is a suitable tool to differentiate between inflammatory and fibrotic lesions, making it useful to decide the appropriate management of each patient

INTRODUCCIÓN: Se necesita una cuantificación adecuada de la actividad inflamatoria en las lesiones de la enfermedad de Crohn (EC) para establecer el tratamiento adecuado para cada paciente. El objetivo de este estudio es evaluar la actividad inflamatoria de los segmentos afectados en las lesiones del intestino delgado mediante estudios dinámicos de enterografía por resonancia magnética (ERM). MÉTODOS: Estudio prospectivo, consecutivo, observacional y clínico, que incluye a todos los pacientes con EC del intestino delgado que se sometieron a cirugía en nuestro centro entre marzo de 2011 y septiembre de 2013. El diagnóstico se estableció de acuerdo con los criterios de Lennard-Jones y la clasificación de Montreal. Todos los pacientes se sometieron a una ERM dentro de los 3 meses previos a la cirugía, aplicando el protocolo de rutina y secuencias preestablecidas. Para el estudio dinámico se empleó la secuencia Adquisición hepática con aceleración de volumen-Volumen extendido (LAVA-XV), antes de la administración intravenosa (IV) de gadolinio, y 30, 70, 120 y 420s después de esta administración. Los resultados permiten diseñar gráficos con diferentes patrones de captación. En el análisis histológico se utilizó la clasificación de Chiorean, así como una versión modificada creada por nuestro grupo de estudio. RESULTADOS: En total se analizaron 28 pacientes con 47 lesiones. Se detectó una correlación significativa entre ambos patrones de curva, incluyendo la clasificación de Chiorean modificada (p < 0,0001), así como el grado inflamatorio (p < 0,0001) y de fibrosis (p < 0,002). Los patrones inflamatorios de los estudios dinámicos se relacionaron con los hallazgos histológicos con una precisión del 80,9% (S=75,7%; E=100%). CONCLUSIÓN: Existe una alta correlación entre los estudios dinámicos y el grado de actividad inflamatoria. La ERM constituye una herramienta adecuada para diferenciar entre lesiones inflamatorias y fibróticas, siendo útil para colaborar en la decisión terapéutica

MRI evaluation of inflammatory activity in Crohn's disease.

OBJECTIVE: We wanted to assess the capability of MRI to quantitatively evaluate the therapeutic response to Crohn's disease (CD) relapse. SUBJECTS AND METHODS: Twenty patients with histologically proven CD were prospectively evaluated with MRI and ileocolonoscopy over a 2-year period. The MRI protocol included axial and coronal T2-weighted and contrast-enhanced T1-weighted sequences. MRI examinations were performed twice, once during an acute relapse of CD and the other at clinical remission. The terminal ileum and colon were divided into six segments/patient, and the endoscopy and histology findings were considered the standard of reference. These were compared on a segmental basis with the quantitative MRI findings regarding wall thickness and contrast enhancement. The results obtained in active and remission CD phases were likewise compared with the findings in 10 control subjects who underwent complete ileocolonoscopy for other reasons and had no pathological findings on ileocolonoscopy. RESULTS: Fifty three of 120 (44.2%) bowel segments showed pathologic changes on endoscopy and histology consistent with CD in active phase. On changing from the active disease phase to clinical remission, a significant decrease was observed in the wall thickness and contrast enhancement of the affected bowel wall. In the active phase of CD, the pathologic bowel segments presented with significantly greater contrast enhancement and wall thickness values compared with the healthy segments of CD and controls. On converting clinically into remission, contrast enhancement tended to normalize, whereas bowel wall thickness remained increased compared with the controls. CONCLUSION: MRI is able to detect pathologic bowel segments in CD, as it allows the measurement of significant variations in wall thickness and contrast enhancement on changing from the active phase of the disease to remission.