Efficacy and Safety of Combined Endovascular Embolization and Stereotactic Radiosurgery for Patients with Intracranial Arteriovenous Malformations: A Systematic Review and Meta-Analysis

Table 2

Subgroup analyses for obliteration rate, rehemorrhage rate, and permanent neurological deficits.

Outcomes	Factors	Groups	No. of studies	OR and 95% CI	value	(%)	statistic	value between subgroups
Obliteration rate	Study design	Prospective	2	1.18 (0.45-3.08)	0.731	0.0	0.946	0.188
		Retrospective	16	0.54 (0.41-0.71)	< 0.001	68.8	< 0.001
	Country	Eastern	6	0.57 (0.41-0.79)	0.001	0.0	0.446	0.538
		Western	12	0.55 (0.39-0.77)	< 0.001	75.4	< 0.001
	Sample size	≥ 100	8	0.58 (0.40-0.84)	0.004	84.3	< 0.001	0.358
		< 100	10	0.53 (0.37-0.76)	0.001	0.0	0.878
	Mean age (years)	≥ 30	13	0.55 (0.39-0.77)	0.001	74.9	< 0.001	0.872
		< 30	5	0.64 (0.48-0.86)	0.003	0.0	0.724
	Nidus volume (ml)	≥ 10	6	0.56 (0.34-0.91)	0.020	0.0	0.823	< 0.001
		< 10	10	0.48 (0.38-0.61)	< 0.001	39.4	0.095
	Margin dose (Gy)	≥ 20	8	0.53 (0.39-0.72)	< 0.001	56.7	0.024	< 0.001
		< 20	8	0.58 (0.39-0.87)	0.009	53.8	0.034
	Intervention	Linear accelerator	4	0.47 (0.30-0.73)	0.001	0.0	0.789	< 0.001
		Gamma knife surgery	9	0.49 (0.38-0.64)	< 0.001	45.4	0.066
		Not mentioned	5	0.96 (0.79-1.17)	0.688	0.0	0.624
	Follow-up (months)	≥ 60	9	0.59 (0.41-0.86)	0.006	80.3	< 0.001	0.036
		< 60	9	0.48 (0.37-0.63)	< 0.001	0.0	0.778
	Study quality	High	11	0.52 (0.38-0.72)	< 0.001	77.7	< 0.001	0.492
		Low	7	0.73 (0.46-1.16)	0.182	0.0	0.618
Rehemorrhage rate	Study design	Prospective	1	0.40 (0.04-3.86)	0.428	—	—	0.395
		Retrospective	9	1.05 (0.81-1.37)	0.708	11.1	0.343
	Country	Eastern	3	1.86 (0.30-11.58)	0.507	51.1	0.129	0.777
		Western	7	1.06 (0.86-1.30)	0.583	0.0	0.476
	Sample size	≥ 100	5	1.10 (0.89-1.34)	0.373	0.0	0.977	0.208
		< 100	5	0.71 (0.21-2.42)	0.583	47.8	0.105
	Mean age (years)	≥ 30	9	1.09 (0.89-1.33)	0.418	0.0	0.565	0.085
		< 30	1	0.23 (0.04-1.33)	0.100	—	—
	Nidus volume (ml)	≥ 10	2	1.87 (0.02-153.75)	0.780	85.2	0.009	0.881
		< 10	6	1.03 (0.72-1.49)	0.864	0.0	0.854
	Margin dose (Gy)	≥ 20	3	1.13 (0.75-1.70)	0.569	0.0	0.882	0.833
		< 20	5	0.85 (0.38-1.92)	0.701	53.9	0.070
	Intervention	Linear accelerator	1	0.37 (0.07-1.99)	0.247	—	—	0.464
		Gamma knife surgery	5	1.09 (0.75-1.58)	0.665	0.0	0.976
		Not mentioned	4	0.93 (0.25-3.37)	0.909	61.1	0.052
	Follow-up (months)	≥ 60	6	1.07 (0.68-1.69)	0.763	32.4	0.193	0.496
		< 60	4	0.91 (0.56-1.48)	0.712	0.0	0.604
	Study quality	High	5	1.08 (0.88-1.32)	0.451	0.0	0.731	0.474
		Low	5	0.87 (0.23-3.27)	0.841	44.3	0.127
Permanent neurological deficits	Study design	Prospective	0	—	—	—	—	—
		Retrospective	7	0.80 (0.48-1.33)	0.385	18.8	0.286
	Country	Eastern	2	0.69 (0.13-3.67)	0.663	0.0	0.981	0.898
		Western	5	0.84 (0.44-1.59)	0.585	45.8	0.117
	Sample size	≥ 100	5	0.89 (0.42-1.86)	0.751	41.2	0.146	0.650
		< 100	2	0.64 (0.27-1.55)	0.325	0.0	0.537
	Mean age (years)	≥ 30	6	0.81 (0.46-1.44)	0.480	32.3	0.194	0.926
		< 30	1	0.67 (0.04-11.73)	0.784	—	—
	Nidus volume (ml)	≥ 10	1	0.54 (0.19-1.53)	0.245	—	—	0.562
		< 10	5	0.83 (0.38-1.80)	0.631	35.9	0.182
	Margin dose (Gy)	≥ 20	4	0.81 (0.30-2.17)	0.674	50.9	0.106	0.774
		< 20	3	0.83 (0.42-1.65)	0.591	0.0	0.550
	Intervention	Linear accelerator	1	1.00 (0.19-5.25)	1.000	—	—	0.595
		Gamma knife surgery	5	0.72 (0.36-1.45)	0.358	37.0	0.174
		Not mentioned	1	1.23 (0.41-3.69)	0.712	—	—
	Follow-up (months)	≥ 60	4	1.40 (0.71-2.79)	0.330	0.0	0.732	0.023
		< 60	3	0.50 (0.28-0.89)	0.018	0.0	0.622
	Study quality	High	6	0.82 (0.46-1.46)	0.498	32.3	0.194	0.929
		Low	1	0.70 (0.09-5.50)	0.735	—	—