Microwave ablation of multifocal primary liver cancer guided by real-time 3.0T MRI

Figures & data

Table 1. Scan parameters.

Parameters	TR (ms)	TE (ms)	FOV (ms)	Thickness (ms)	Spacing (ms)	Bandwidth (ms)	ETL	Nex	Scanning time(s)
T2WI SSFSE	2333	79.36	42	4	5	62.5	/	0.56	10
LAVA-Flex	5.0	MiniFull	40	5	0	142.86	/	1	15
T2WI PROPELLER	8571	64	34	7	1	83.33	28	3.0	60

T2WI SSFSE: T2-weighted image single shot fast spin-echo; LAVA-Flex: liver acquisition with volume acceleration Flex; T2WI PROPELLER: T2-weighted image PROPELLER; TR: repetition time; TE: echo time; FOV: field of view; ETL: echo train length; Nex: number of excitation.

Table 2. Patient characteristics.

Characteristics	Value
Average age (years)	60.12 ± 8.84
>60	14 (53.8%)
≤60	12 (46.2%)
Sex
Male	24 (92.3%)
Female	2 (7.7%)
Number of tumors
2	13 (50%)
3	7 (26.9%)
4	3 (11.5%)
5	1 (3.9%)
6	2 (7.7%)
Average diameter (cm)	1.81 ± 0.94
≤3	70 (92.1%)
3 ∼ 5	6 (7.9%)
Liver function
Child-Pugh A	11 (42.3%)
Child-Pugh B	15 (57.7%)
AFP
≥100	14 (53.8%)
＜100	12 (46.2%)
Average ablation time (min)	11.00 ± 4.05
Average ablation power (W)	43.03 ± 4.45
Average operation time (min)	103.58 ± 18.57
Cirrhosis
With	24 (92.3%)
Without	2 (7.7%)
Needle (s)
1	74 (92.3%)
2	2 (7.7%)

AFP: alpha fetoprotein.

Table 3. Complications (SIR categories).

Complications	N
Adverse events
Biliary fistula (D)	0
Pulmonary embolism (D)	0
Transfer (E)	0
Minor complications
Pain (B)	1
Pleural effusion (B)	1
Total	7.7%

SIR: Society of Interventional Radiology.

Figure 1. Pre-ablation imaging: a 60-year-old male patient with multifocal liver cancer recurred after TACE. Abnormal nodules were seen in the S4 and S5 segment. liver-specific contrast enhanced scan showed slightly low signal (a,b). the scanning equipment was Ge MR750W with the following parameters: FOV = 40 cm, phase FOV = 0.8, and layer thickness 5.0 mm. Matrix = 256 * 192, NEX = 1, bandwidth = 142.8, flip angle = 15.

Figure 2. Intraoperative imaging: the microwave ablation needle showed low signal in all sequences and was inserted into the center of the tumor step by step (a,b). the scanning equipment was Ge MR750W with the following parameters: FOV = 40 cm, phase FOV = 0.8, and layer thickness 5.0 mm. Matrix = 256 * 192, NEX = 1, bandwidth = 142.8, flip angle = 15.

Figure 3. Post-ablation imaging: after the ablation was completed, the ablation lesion displayed a ‘target sign’ in the LAVA-Flex sequence (a,b). the scanning equipment was Ge MR750W with the following parameters: FOV = 40 cm, phase FOV = 0.8, and layer thickness 5.0 mm. Matrix = 256 * 192, NEX = 1, bandwidth = 142.8, flip angle = 15.