PMC4001425_01
PMC4001425_02
Needle insertion, laser fiber introduction and thermal monitoring of treatment. (a) Patient 2, liver tumor at segment 3. Needle (arrows) is inserted to the tumor (arrowheads) under MR guidance. (b) Patient 2, laser fiber (arrows) introduced into the tumor (arrowheads), same location as in (a). (c) Patient 2, thermal monitoring of laser treatment, MRI signal decrease is evident in the tumor area (arrowheads) after 10 min of treatment. Same location as in (a, b).
10.1177_2047981613499753-fig1.jpg
PMC4001425_02_10.1177_2047981613499753-fig1.jpg
fig1-2047981613499753
After reaching the target, needle was replaced with laser treatment instrumentation under MRI guidance (Fig. 1).  TE, 3.8 ms; slices, 8; slice thickness/interval, 6.0/6.0 mm; field of view [FOV], 380 x 380; matrix, 160 x 160; FA, 63 degrees; acquisition time, 24 s) observing the change in T1 signal intensity, which was expressed as a signal void in the image (Fig. 1). This signal void was attributable to the temperature change in the heated tissue. The imaging sequence was repeated at 1 min 30 s intervals. FSE; TE, 140 ms; TR, 5000; slices, 14; slice thickness/interval, 7/8 mm; FOV, 360 x 309 mm; matrix, 256 x 216, estimated acquisition time, 5 min). Then, contrast-enhanced sequences were acquired. First a breath-hold, T1-weighted dynamic (Fig. 1) (T1 FE3D; TR, 13 ms; TE, 5.2 ms; slices, 64; slice thickness/interval, 7/7 mm; FOV, 350 x 350 mm; matrix 192 x 192; FA, 20 degrees; acquisition time, 33 s) sequence image set without fat saturation was acquired before the contrast agent administration.
Postprocedural MRI at 72 h after therapy: Patient 2, dynamic T1-weighted imaging. Ablation sites are depicted as non-perfusing regions (arrowheads) in segments II and III.
10.1177_2047981613499753-fig2.jpg
PMC4001425_02_10.1177_2047981613499753-fig2.jpg
fig2-2047981613499753
TR, 500 ms; slices, 12; slice thickness/interval, 7/8 mm; FOV, 360 x 300 mm; matrix 324 x 270; acquisition time 5 min 40 s). The patients were monitored for 6 h in the recovery room. The previously described MRI protocol was repeated at 72 h from the treatment (Fig. 2) and the patients were dispatched from the hospital. The further imaging protocol was scheduled to occur with in clinical follow-up schedule, first two computed tomography (CT) or MRI scans with 6-month intervals, followed by clinical follow-up with either MRI, CT, or US imaging performed annually.