mrimaster

MRI Defecography (Proctogram)

Indications for mri Defecography (Proctogram) scan

Contraindications

Patient preparation for Defecography (Proctogram)

Positioning for Defecography (Proctogram)

mri proctogram scan positioning photo

Recommended MRI Defecography (Proctogram) Protocols and Planning

MRI Defecography localiser

A three-plane localizer must be taken at the beginning to localize and plan the sequences. Localizers are normally less than 25 seconds and are T1\T2-weighted low-resolution scans.

T2 tse sagittal 3mm SFOV pre proctogram

Plan the sagittal slices on the axial plane; angle the positioning block parallel to the interpubic fibrocartilage and the anal canal. Check the positioning block in the other two planes. An appropriate angle must be given in the coronal plane (parallel to the rectum and the anal canal). Slices must be sufficient to cover the whole pelvis from the right acetabulum to the left acetabulum. FOV must be big enough to cover the whole pelvis (normally 270mm-300mm). Adding saturation bands on top and front of the sagittal block will reduce artifacts from arterial pulsation and breathing.

Parameters

TR

4000-5000

TE

100-120

SLICE

3 MM

FLIP

130-150

PHASE

A>P

MATRIX

320X320

FOV

270-300

GAP

10%

NEX(AVRAGE)

3

T2 tse axial oblique 3mm SFOV pre proctogram

Plan the axial oblique slices on the sagittal plane; angle the positioning block perpendicular to the anal canal. Check the positioning block in the other two planes. An appropriate angle must be given in the coronal plane (perpendicular to the anal canal). Slices must be sufficient to cover the entire anal canal.

Parameters

TR

4000-5000

TE

100-120

SLICE

3 MM

FLIP

130-150

PHASE

A>P

MATRIX

320X320

FOV

180-230

GAP

10%

NEX(AVRAGE)

4

T2 tse coronal oblique 3mm SFOV pre proctogram

Plan the coronal oblique slices on the sagittal plane; angle the positioning block parallel to the anal canal. Check the positioning block in the other two planes. An appropriate angle must be given in the axial plane (horizontally across the anal canal or parallel to the right and left hip joint). Slices must be sufficient to cover the whole anal canal.

Parameters

TR

3000-4000

TE

100-120

SLICE

3 MM

FLIP

130-150

PHASE

R>L

MATRIX

320X256

FOV

180-230

GAP

10%

NEX(AVRAGE)

5

pause for proctogram

Next, guide the patient to lie down in either a right or left lateral position. The radiologist will gently insert a small catheter lubricated with ky jelly into the rectum and inject a small amount of sonography gel. Afterward, remove the catheter and place the patient back into the initial position. Instruct the patient to clench, relax, and strain during image capture.

localiser

A three-plane localizer must be taken at the beginning to localize and plan the sequences. Localizers are normally less than 25 seconds and are T1\T2-weighted low-resolution scans.

T2 TRUFISP cine, small FOV 10mm, 1 second, 150 measurements.

Plan the sagittal slices on the axial plane; angle the positioning block parallel to the interpubic fibrocartilage and the anal canal. Check the positioning block in the other two planes. An appropriate angle must be given in the coronal plane (parallel to the rectum and the anal canal). Slice must be positioned over the middle of the rectum and anal canal.

After approximately five measurements, instruct the patient to strain and expel the gel from the rectum onto the incopads beneath, while ensuring that cine scans are continuously running during this process.

Parameters

TR

40-50

TE

1-2

SLICE

5-10 MM

FLIP

70

PHASE

A>P

MATRIX

208X208

FOV

250-300

OVERS.

50%

CINE

150measurement