Meta-Analysis of Clipping versus Coiling for the Treatment of Unruptured Middle Cerebral Artery Aneurysms: Direct Comparison of Procedure-Related Complications

Figures & data

Figure 1 Flowchart of the study selection process.

Table 1 Quality Assessment Scores of the Included Studies

Study, Year	Design	Newcastle-Ottawa Scale
		Selection	Comparability	Exposure	Total Scores
Dammann et al,^Citation14 2014	Retrospective cohort study	3	2	1	6
Diaz et al,^Citation15 2014	Retrospective cohort study	3	2	1	6
Güresir et al,^Citation7 2011	Prospective cohort study	2	2	1	5
Jang et al,^Citation16 2015	Retrospective cohort study	2	2	1	5
Regli et al,^Citation17 1999	Prospective cohort study	2	2	2	6
Steklacova et al,^Citation18 2016	Retrospective cohort study	3	2	2	7

Table 2 Overview of Included Studies

Author	Country	Years	Enrollment	Study Design	Participants (n)		Age (Mean ± Standard)		NOS
Period					Coil	Clip	Coil	Clip	Scores
Dammann et al^Citation14	Germany	2014	2006-2010	Retrospective	16	87	54	53.7	6
Diaz el al^Citation15	USA	2014	2005-2010	Retrospective	40	25	NA	NA	6
Güresir et al^Citation7	Germany	2011	1999-2009	Prospective	21	108	NA	NA	5
Jang et al^16	Korea	2015	1999-2013	Retrospective	25	286	NA	NA	5
Regli et al^Citation17	Switzerland	1999	1993-1997	Prospective	13	32	NA	NA	6
Steklacova et al^Citation18	Czech	2016	2000-2013	Retrospective	29	107	NA	NA	7

Abbreviation: NA, not available.

Figure 2 Forest plot of odds ratio (OR) of retreatment with endovascular coiling vs. surgical clipping.

Figure 3 Forest plot of rate difference (RD) of postoperative death with endovascular coiling vs. surgical clipping.

Figure 4 Forest plot of odds ratio (OR) of postoperative completed occlusion with endovascular coiling vs. surgical clipping.

Figure 5 Forest plot of odds ratio (OR) of postoperative surgical complication with endovascular coiling vs. surgical clipping.

Figure 6 Forest plot of odds ratio (OR) of postoperative thrombus without infarction with endovascular coiling vs. surgical clipping.

Table 3 Meta-Analysis Results

Outcome	Studies	Groups		Overall Effect			Heterogeneity
		Clip	Coil	Effect Estimate	95% CI	p-Value	I^2(%)	p-Value
Retreatment	2	119	29	104.926	12.931–851.379	<0.001	5.8%	0.303
Postoperative death	4	334	79	0.012	−0.030–0.055	0.567	0.0%	0.899
Postoperative bleed (short term)	2	133	61	0.012	−0.040–0.063	0.658	0.0%	0.623
Postoperative bleed (long term) at follow	2	394	46	−0.002	−0.045–0.041	0.927	0.0%	0.934
Post-operative occlusion (complete)	2	112	56	0.349	0.140–0.872	0.024	0.0%	0.803
MRS >2 at follow	2	133	61	3.276	0.690–15.555	0.135	0.0%	0.318
GOS (4–5) at follow	2	194	45	0.250	0.072–0.867	0.029	0.0%	1.000
Postoperative surgical complications	5	537	123	3.157	1.239–8.048	0.016	0.0%	0.569
Postoperative Thrombus w/o Infraction	3	240	90	4.905	1.097–21.933	0.037	0.0%	0.390
Infraction	3	497	75	0.020	−0.026–0.066	0.401	27.7%	0.251

Note: Bold font indicates that the p-value of a result was less than 0.05 and regarded as statistically significant.

Abbreviations: MRS, modified Rankin scale; GOS, Glasgow Outcome Scale; w/o, without.

Figure 7 Forest plot of odds ratio (OR) of postoperative Glasgow Outcome Scale (GOS) with endovascular coiling vs. surgical clipping.

Figure 8 Forest plot of odds ratio (OR) of postoperative modified Rankin scale (mRS) with endovascular coiling vs. surgical clipping.

Dammann P, Schoemberg T, Müller O, et al. Outcome for unruptured middle cerebral artery aneurysm treatment: surgical and endovascular approach in a single center. Neurosurg Rev. 2014;37(4):643–651. doi:10.1007/s10143-014-0563-525005630

 PubMed Web of Science ®Google Scholar

Diaz OM, Rangel-Castilla L, Barber S, et al. Middle cerebral artery aneurysms: a single-center series comparing endovascular and surgical treatment. World Neurosurg. 2014;81(2):322–329. doi:10.1016/j.wneu.2012.12.01123238101

 PubMed Web of Science ®Google Scholar

Güresir E, Schuss P, Berkefeld J, Vatter H, Seifert V. Treatment results for complex middle cerebral artery aneurysms. A prospective single-center series. Acta Neurochir (Wien). 2011;153(6):1247–1252. doi:10.1007/s00701-011-1008-321487768

 PubMed Web of Science ®Google Scholar

Jang EW, Kim YB, Chung J, et al. Clinical risk factors affecting procedure-related major neurological complications in unruptured intracranial aneurysms. Yonsei Med J. 2015;56(4):987–992.26069121

 PubMed Web of Science ®Google Scholar

Regli L, Uske A, de Tribolet N. Endovascular coil placement compared with surgical clipping for the treatment of unruptured middle cerebral artery aneurysms: a consecutive series. J Neurosurg. 1999;90(6):1025–1030. doi:10.3171/jns.1999.90.6.102510350247

 PubMed Web of Science ®Google Scholar

Steklacova A, Bradac O, Charvat F, De Lacy P, Benes V. “Clip first” policy in management of intracranial MCA aneurysms: single-centre experience with a systematic review of literature. Acta Neurochir (Wien). 2016;158(3):533–546; discussion 546. doi:10.1007/s00701-015-2687-y

 Web of Science ®Google Scholar