Keywords:
Urinary Tract / Bladder, MR, Diagnostic procedure, Contrast agent-intravenous
Authors:
S. Donaldson1, B. Carrington1, R. Cowan1, J. Lyons1, D. Buckley2, S. Bonington1; 1Manchester/UK, 2Leeds/UK
DOI:
10.1594/ecr2011/C-2308
Methods and Materials
Patients
- 12 patients with primary bladder cancer (9 M,
3 F; age = 45 – 73 yrs,
mean = 60 yrs).
- DCE-MRI performed before and after treatment with neo-adjuvant chemotherapy (mean time of scan after completing neo-adjuvant chemotherapy = 34 days,
range = 27 – 44 days).
- Early toxicity symptoms were reported by patients.
MR protocol
- 1.5 T Siemens Magnetom Avanto.
- T2-w scans for localisation of suspicious area.
- 0.1 mmol/kg Gd-DTPA injected intravenously.
- 3D axial T1-weighted VIBE sequence used for acquisition of dynamic series:
- TR / TE = 5.6 / 1.1 ms
- α = 25o
- 144 x 192 matrix
- section thickness = 5.0 mm x 16 slices
- acquisition time = 2.5 s for coverage
- Scan duration = 4 mins
- Prior to this acquisition,
the VIBE sequence was run with multiple flip angles (α = 5o,
10o,
35o) in order to obtain pre-contrast T1 estimates.
Data analysis
- For each patient a volume of interest (VOI) was defined pre- and post-chemotherapy in:
- normal bladder wall.
- rectum.
- Signal-time curves from each VOI were analysed with the 2CXM to estimate perfusion,
Fp.
- Differences and changes in perfusion before and after treatment were compared using a paired t-test.