Contrast-enhanced MRI of the small bowel in Crohn’s disease

Abstract

Recently, magnetic resonance imaging has emerged as a valuable tool in evaluation of small bowel Crohn's disease. MRI provides several advantages to other imaging modalities, including the lack of ionizing radiation, multiplanar capability, and functional information. Intravenous contrast administration is a routine portion of MR enterography protocol, and aids in detection of disease extent, extramural complications such as fistula and abscess, and assessment of activity. Additionally, promising techniques such as dynamic contrast-enhanced MRI may provide quantitative measures to assess bowel perfusion, which may enhance evaluation of disease activity. This article will provide an overview of the technical aspects of contrast-enhanced MR enterography, describe common pathologic findings involving the small bowel in Crohn's disease, summarize its role in determination of activity with an emphasis on endoscopic and histologic correlation, and compare its efficacy with other imaging modalities.

Prospective Evaluation of MR Enterography as the Primary Imaging Modality for Pediatric Crohn Disease Assessment

“…At the least,, substituting CT with MR-E in the pediatric Crohn's population makes sense, given the higher radiation sensitivity and increased imaging-associated radiation exposure of this group compared with the adult Crohn's population ([8]). Such a change in practice would be consistent with recent calls in the radiology literature for increased utilization of MR enterography in the adult Crohn's population[34]. It is likely that a combination of CT dose reduction techniques and increased MR enterography utilization will become a standard part of Crohn's disease imaging evaluation in the coming years.…”

Crohn’s disease: prevalence of intestinal and extraintestinal manifestations detected by computed tomography enterography with water enema

“…Currently MR-and CT-enterography and enteroclysis are the most accurate imaging techniques to establish CD extension in the small intestine and to depict extraluminal complications [15,[36][37][38][39].…”

Magnetinio rezonanso enterokolonografijos reikšmė diagnozuojant uždegimines žarnyno ligas

“…Šie pakitimai yra nenustatomi MRT enterokolonografijos metu, tačiau gilios opos yra gerai matomos tiek T1, tiek T2 sekose [8]. Pagal J. Oommen ir bendraautorius peroralinės kontrastinės medžiagos ištemptos žarnos sienelės storis (> 3mm) jautrus, bet nespecifinis aktyvios KL požymis [9]. Žarnos sienelės sustorėjimas geriausiai matomas T1, T2 sekose, jį matuoti rekomenduojama ašiniuose pjūviuose.…”

“…Sienelės sustorėjimas yra antrinis dėl edemos ir uždegiminių infiltratų. Vis dėlto sienelės sustorėjimas matomas ir esant lėtinei ligos formai dėl išsivysčiusios fibrozės [9]. Todėl, nustatant OK ir KL ligų aktyvumo laipsnius, įvertinami ir kiti žemiau išvardinti požymiai.…”

“…tyrinėjo, kaip pakitimai MRT vaizduose koreliuoja su endoskopinio ir histologinio tyrimų rezultatais, ir nustatė, kad sienelės kaupimasis sluoksniais yra specifinis aktyviai UŽL, kadangi jis buvo nustatytas tik segmentuose su įrodyta aktyvia liga. Be to, tyrėjai patvirtino, kad žarnos sienelės storis didesnis nei 4 mm ir kontrastinės medžiagos kaupimo savybės koreliuoja su ligos aktyvumu [9].…”