Limits...
Small bowel MR enterography: problem solving in Crohn's disease.

Griffin N, Grant LA, Anderson S, Irving P, Sanderson J - Insights Imaging (2012)

Bottom Line: Clinical indices, endoscopic and histological findings have traditionally been used as surrogate markers but all have limitations.MRE can help address this question.The purpose of this pictorial review is to (1) detail the MRE protocol used at our institution; (2) describe the rationale for the MR sequences used and their limitations; (3) compare MRE with other small bowel imaging techniques; (4) discuss how MRE can help distinguish between inflammatory, stricturing and penetrating disease, and thus facilitate management of this difficult condition.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Guy's & St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK, nyreegriffin100@gmail.com.

ABSTRACT
Magnetic resonance enterography (MRE) is fast becoming the first-line radiological investigation to evaluate the small bowel in patients with Crohn's disease. It can demonstrate both mural and extramural complications. The lack of ionizing radiation, together with high-contrast resolution, multiplanar capability and cine-imaging make it an attractive imaging modality in such patients who need prolonged follow-up. A key question in the management of such patients is the assessment of disease activity. Clinical indices, endoscopic and histological findings have traditionally been used as surrogate markers but all have limitations. MRE can help address this question. The purpose of this pictorial review is to (1) detail the MRE protocol used at our institution; (2) describe the rationale for the MR sequences used and their limitations; (3) compare MRE with other small bowel imaging techniques; (4) discuss how MRE can help distinguish between inflammatory, stricturing and penetrating disease, and thus facilitate management of this difficult condition. Main Messages • MR enterography (MRE) is the preferred imaging investigation to assess Crohn's disease. T2-weighted, post-contrast and diffusion-weighted imaging (DWI) can be used. • MRE offers no radiation exposure, high-contrast resolution, multiplanar ability and cine imaging. • MRE can help define disease activity, a key question in the management of Crohn's disease. • MRE can help distinguish between inflammatory, stricturing and penetrating disease. • MRE can demonstrate both mural and extramural complications.

No MeSH data available.


Related in: MedlinePlus

Coronal True FISP image: normal bowel. The ‘black boundary’ artefact may be confused with bowel wall thickening (arrows)
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3369125&req=5

Fig1: Coronal True FISP image: normal bowel. The ‘black boundary’ artefact may be confused with bowel wall thickening (arrows)

Mentions: The True FISP (fast imaging with steady state precession) sequence consists of a balanced gradient echo sequence where image contrast is dependent on T2*/T1 ratio. It gives high-contrast, predominantly T2*-weighted images. True FISP eliminates phase shifts caused by motion and thus both fluid and blood appear bright. It is a fast acquisition due to a short repetition time (TR) and echo time (TE) with each image acquired in a few hundred milliseconds. Susceptibility artefact occurs with the presence of intraluminal gas or ferromagnetic material, leading to image distortion. Off-resonance artefacts occur in the presence of a non-uniform magnetic field, resulting in banding artefact (alternating stripes) at the periphery of the image. Chemical-shift artefact results in a ‘black boundary’ effect around structures (Fig. 1). This makes mesenteric nodes and vessels more conspicuous but may impede assessment of bowel wall thickening. This sequence provides good delineation between the bowel and the mesentery.Fig. 1


Small bowel MR enterography: problem solving in Crohn's disease.

Griffin N, Grant LA, Anderson S, Irving P, Sanderson J - Insights Imaging (2012)

Coronal True FISP image: normal bowel. The ‘black boundary’ artefact may be confused with bowel wall thickening (arrows)
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3369125&req=5

Fig1: Coronal True FISP image: normal bowel. The ‘black boundary’ artefact may be confused with bowel wall thickening (arrows)
Mentions: The True FISP (fast imaging with steady state precession) sequence consists of a balanced gradient echo sequence where image contrast is dependent on T2*/T1 ratio. It gives high-contrast, predominantly T2*-weighted images. True FISP eliminates phase shifts caused by motion and thus both fluid and blood appear bright. It is a fast acquisition due to a short repetition time (TR) and echo time (TE) with each image acquired in a few hundred milliseconds. Susceptibility artefact occurs with the presence of intraluminal gas or ferromagnetic material, leading to image distortion. Off-resonance artefacts occur in the presence of a non-uniform magnetic field, resulting in banding artefact (alternating stripes) at the periphery of the image. Chemical-shift artefact results in a ‘black boundary’ effect around structures (Fig. 1). This makes mesenteric nodes and vessels more conspicuous but may impede assessment of bowel wall thickening. This sequence provides good delineation between the bowel and the mesentery.Fig. 1

Bottom Line: Clinical indices, endoscopic and histological findings have traditionally been used as surrogate markers but all have limitations.MRE can help address this question.The purpose of this pictorial review is to (1) detail the MRE protocol used at our institution; (2) describe the rationale for the MR sequences used and their limitations; (3) compare MRE with other small bowel imaging techniques; (4) discuss how MRE can help distinguish between inflammatory, stricturing and penetrating disease, and thus facilitate management of this difficult condition.

View Article: PubMed Central - PubMed

Affiliation: Department of Radiology, Guy's & St Thomas' Hospital, Westminster Bridge Road, London, SE1 7EH, UK, nyreegriffin100@gmail.com.

ABSTRACT
Magnetic resonance enterography (MRE) is fast becoming the first-line radiological investigation to evaluate the small bowel in patients with Crohn's disease. It can demonstrate both mural and extramural complications. The lack of ionizing radiation, together with high-contrast resolution, multiplanar capability and cine-imaging make it an attractive imaging modality in such patients who need prolonged follow-up. A key question in the management of such patients is the assessment of disease activity. Clinical indices, endoscopic and histological findings have traditionally been used as surrogate markers but all have limitations. MRE can help address this question. The purpose of this pictorial review is to (1) detail the MRE protocol used at our institution; (2) describe the rationale for the MR sequences used and their limitations; (3) compare MRE with other small bowel imaging techniques; (4) discuss how MRE can help distinguish between inflammatory, stricturing and penetrating disease, and thus facilitate management of this difficult condition. Main Messages • MR enterography (MRE) is the preferred imaging investigation to assess Crohn's disease. T2-weighted, post-contrast and diffusion-weighted imaging (DWI) can be used. • MRE offers no radiation exposure, high-contrast resolution, multiplanar ability and cine imaging. • MRE can help define disease activity, a key question in the management of Crohn's disease. • MRE can help distinguish between inflammatory, stricturing and penetrating disease. • MRE can demonstrate both mural and extramural complications.

No MeSH data available.


Related in: MedlinePlus