Elucidating vaginal fistulas on CT and MRI

Insights into Imaging

Table 3 Focused MRI acquisition protocol for the study of the ano-perineal region

Sequence	Orientation	FOV (mm)	Matrix	No. of slices	Section thickness (mm)^b	No. of averages	TR/TE (ms) (range)^c
T2-w TSE	Sagittal	240	344 × 388	25	3.5	1–2	2500–5000/90
T2-w TSE	Axial/oblique-axial	220	320 × 311	35–40	3	2	2800–5000/90
T2-w TSE	Coronal/oblique-coronal	240	344 × 388	25	3.5	1–2	2500–5000/90
FS T2-w SPAIR	Axial	240	268 × 262	30–35	3.5	2	3000–5000/90
EPI DW	Axial	240	75 × 65	30–35	3.5	3	Shortest^d
(if not contraindicated) i.v. paramagnetic contrast medium such as as 1-M gadobutrol (Gadovist, Bayer – Germany) 0.1 ml/kg
FS T1-w SPIR^a	Sagittal	240	344 × 388	25	3	1–2	400–700/10
FS T1-w SPIR^a	Axial/oblique-axial	220	320 × 311	35–40	3.5	2	400–700/10
FS T1-w SPIR^a (optional)	Coronal/oblique-coronal	240	344 × 388	25	3.5	1–2	400–700/10

FOV field-of-view, TR repetition time, TE echo time, T2-w T2-weighted, T1-w T1-weighted, TSE turbo spin-echo, SPAIR Spectral Attenuated Inversion Recovery, EPI echo-planar imaging, DW diffusion-weighted imaging, FS fat-suppressed, SPIR Spectral Presaturation with Inversion Recovery - ^amay be replaced with volumetric FS T1-w gradient-echo sequences such as THRIVE (T1 high-resolution isotropic volume excitation), LAVA (liver acquisition with volume acquisition) or VIBE (volumetric interpolated breath-hold examination). ^bMinimal (10%) intersection gap. ^cAutomatically selected in relation to geometrical parameters. ^dFour b values (0… 1000 mm²/s)