Keywords:
Neuroradiology brain, Oncology, Computer applications, MR-Diffusion/Perfusion, MR-Functional imaging, MR, Diagnostic procedure, Imaging sequences, Observer performance, Neoplasia, Multidisciplinary cancer care, Image verification
Authors:
P. M. Gonçalves Pereira1, G. Neto d´Almeida 1, P. Escada1, R. Manaças1, T. Taoka2; 1Lisboa/PT, 2Kashihara/JP
DOI:
10.1594/ecr2013/C-2370
Methods and Materials
14 patients with histologically proven VS were evaluated.
DT images (1,5T) and tractography of the FN was performed accordingly to the method of Taoka T.
et al1,2.
Briefly,
DT images were obtained with a single-shot echo-planar sequence (TR 4900 msec,
TE 85 msec,
b 1000 sec/mm2,
six-axis encoding,
FOV 230 mm,
matrix 128 x 128,
spacing 3 mm,
4 averages,
35 slices).
For each patient,
the most convex angle that the FN tract formed between its extremities in the axial plane was calculated as an index of displacement (Figures 1 and 2).
Data was correlated to the size of the tumors (Koos scale) and Inter-observer agreement was determined (ICC - Intraclass Correlation Coefficient).
Figure 1
Right-CPA grade 4 Vestibular Schwannoma.
(A) Axial T1 pos-Gad.
(B) Facial nerve pre-operative tractography (PMGP),
upper-view with orthogonal reference planes.
(C) Axial plane FN tractography (PMGP).
The displacement angle is 105º.
(D) Axial plane FN tractography (TT).
The displacement angle is 111º.
Figure 2
Corresponding surgical image for the case shown in Fig.1.
Pre-operative tractography matched the exact location of the facial nerve.