Systematic review and risk factor analysis of post-vitrectomy silicone oil migration to the central nervous system

Table 2 Details comparison of eyes included in group 1 and group 2, n (%)

	Group 1 (n = 11)	Group 2 (n = 43)	Fisher's exact test	Mann-Whitney U tests	Binary logistic regression
Patient demographics
Male	6 (54.5)	25 (58.1)	P = 1.00		P = 0.152
Age (years) mean ± SD	55.8 ± 17.5	59.9 ± 16.1		P = 0.43	P = 0.664
Diabetes mellitus	2 (18.2)	23 (53.5)	P = 0.05		aP = 0.037
Visual acuity (logMAR)	2.74± 1.00	2.84± 0.42		P = 0.06	aP = 0.011
SiO-filled eyes' ocular characteristics
Congenital disc pit	0 (0.0)	1 (2.3)	P = 1.00		P = 0.424
Optic nerve atrophy/cupping	2 (18.2)	9 (21.0)	P = 1.00		P = 0.790
Scleral buckle	1 (9.1)	2 (4.7)	P = 0.50		P = 0.696
Glaucoma drainage device	0 (0.0)	3 (7.0)	P = 1.00		P = 0.242
Vitrectomy surgical details
Post-operative intraocular pressure (mmHg)	31.9± 16.2	49.1± 16.5		aP = 0.047	aP = 0.012
SiO emulsification	1 (9.1)	2 (4.7)	P = 0.50		P = 0.696
Endotamponade time (months)	10.3± 10.9	67.3± 64.8		aP = 0.002	P = 0.152
Presenting symptoms
Headache	3 (27.3)	17 (39.5)	P = 0.73		P = 0.869
Nausea	0 (0.0)	4 (9.3)	P = 0.57		P = 0.424
Dizziness	2 (18.2)	7 (16.3)	P = 1.00		P = 0.242
Loss of consciousness	1 (9.1)	9 (21.0)	P = 0.67		P = 0.242
Mental change	1 (9.1)	5 (11.6)	P = 1.00		P = 0.424
Painful eye	2 (18.2)	2 (4.7)	P = 0.18		P = 0.696
Visual field loss	1 (9.1)	0 (0.0)	P = 0.20		P = 0.182
Visual change	2 (18.2)	8 (18.6)	P = 1.00		P = 0.790

^aP < 0.05.

SiO: Silicone oil.