Assessment of liver ablation using cone beam computed tomography

Table 1 Patients and ablation characteristics

Patient	Sex	Age (yr)	Tumor size (mm)	Tumor volume (cm3)	Ablation volume (cm3)		Registration		CBCT image quality
					CBCT	MDCT	Quality	Time (mo)
1	M	71	30	13.0	40	32	2	3.9	3
2	M	63	25	8.5	10	12	1	3.3	2
3	M	74	32	16.0	37	55	3	3.4	1
4	M	74	35	22.0	77	69	3	3.3	3
5	M	55	40	36.0	58.5	46	2	6.3	3
6	M	46	15	3.0	12	7.5	3	5	3
7	M	46	30	14.0	38	30	3	8	2
8	M	46	12	2.5	30	32	3	8	2
9	M	68	30	13.5	33	59	3	4.2	2
10	M	65	14	3.0	10	17	1	4	1
11	M	86	8	0.5	58	38	1	7	2
12	F	68	20	5.0	4	13	1	5	2
13	M	60	15	3.5	47	34	1	8	2
14	F	56	30	13.0	32	38	3	7	3
15	F	84	22	6.0	10	12	3	4	3
16	M	54	35	27.0	95	124	3	5	3
17	M	81	24	8.5	8	9	3	5	3
18	F	76	13	3.0	8	6	3	3	3
19	F	76	14	3.5	10	11	2	3	3
20	M	77	18	4.0	31	29	3	5	3
21	M	77	11	2.5	13	30	3	5	3
22	F	50	13	3.0	27	19	2	6	3
23	M	57	14	3.5	7	4	1	8	2

Registration quality of the liver contours was rated as follows: (1) poor registration (> 20 mm for liver contours); (2) good registration (between 5-20 mm for both liver vessels and liver contours); and (3) excellent registration for both liver vessels and liver contours (< 5 mm for both liver vessels and liver contours). Cone beam computed tomography (CBCT) image quality was evaluated as follows: (1) poor quality: no visible ablation; (2) good quality: detection of ablation but presence of artifacts which hamper clear delineation; and (3) excellent quality: detection of ablation and no artifacts. Registration time corresponds to the duration of the software manipulation to achieve the best image fusion between baseline computed tomography and periprocedural CBCT. MDCT: Multidetector computed tomography.