Intraocular pressure 1 year after vitrectomy in eyes without a history of glaucoma or ocular hypertension

Figures & data

Table 1 Demographics of the study population

	Patients without elevated IOP		Patients with elevated IOP		P-value
	N=206	%	N=50	%
Age (years)					0.192*
Mean ± SD	50.8±16.6		46.3±13.3
Range	5–80		9–67
Preoperative IOP (mm Hg)					0.980*
Mean ± SD	12.6±4.1		12.9±4.2
Range	5–20		3–21
Diopter (D)					0.971*
Mean ± SD	−3.0±5.6		−3.6±5.0
Range	−27 to 2		−14 to 2
Gender					0.864†
Male	125	60.68%	31	62.00%
Female	81	39.32%	19	38.00%
Medical history
DM	39	18.93%	10	20.00%	0.863†
HP	43	20.87%	6	12.00%	0.153†

Notes:

* P-value by independent t-test.

† P-value by Pearson’s χ² test.

Abbreviations: DM, diabetes mellitus; HP, hypertension; IOP, intraocular pressure.

Table 2 Intraoperative characteristics of patients with and without elevated IOP

	Patients without elevated IOP		Patients with elevated IOP		P-value
	N=206	%	N=50	%
Diagnosis					0.181*
Macular diseases	26	12.62	1	2.00
Vitreous hemorrhage	19	9.22	2	4.00
Retinal detachment	91	44.17	24	48.00
Trauma related	40	19.42	11	22.00
PDR	24	11.65	8	16.00
Others	6	2.91	4	8.00
Tamponade					0.036*
Air	10	4.85	0	0.00
BSS	33	16.02	4	8.00
SF6	16	7.77	1	2.00
C3F8	89	43.20	22	44.00
Silicone oil	58	28.16	23	46.00
Combined lens surgery					0.336*
Without lens surgery	133	64.56	35	70.00
Lensectomy	43	20.87	12	24.00
Lensectomy + IOL	27	13.11	2	4.00
IOL removal	3	1.46	1	2.00
Combined scleral buckling					0.541*
Without SB	191	92.72	48	96.00
With SB	15	7.28	2	4.00

Note:

* P-value by Pearson’s χ² test.

Abbreviations: SF6, sulfur hexafluoride; C3F8, perfluoropropane; BSS, balanced salt solution; IOL, intraocular lens; IOP, intraocular pressure; PDR, proliferative diabetic retinitis; SB, scleral buckling.

Figure 1 Comparison of the total proportion of eyes with elevated IOP among the different tamponade groups.

Notes: The proportion of eyes with elevated IOP was significantly higher in the silicone oil group than in the others group (combined air, BSS, and SF6 groups; P=0.002, Pearson’s χ² test). The proportion of eyes with elevated IOP was significantly higher in the C3F8 group than in the others group (P=0.034, Pearson’s χ² test). There was no significant difference in the proportion of eyes with elevated IOP between the silicone oil group and the C3F8 group (P=0.166, Pearson’s χ² test). ^*Significant; ^**highly significant.
Abbreviations: SF6, sulfur hexafluoride; C3F8, perfluoropropane; BSS, balanced salt solution; IOP, intraocular pressure; NS, not significant.

Figure 2 Survival analysis of elevated IOP according to the type of tamponade used in PPV.

Note: The cumulative rate of elevated IOP was significantly different among the five types of tamponade (P=0.008, log-rank test) and was greatest for silicone oil tamponade.
Abbreviations: SF6, sulfur hexafluoride; C3F8, perfluoropropane; BSS, balanced salt solution; IOP, intraocular pressure; M, month; PPV, pars plana vitrectomy; W, week.

Table 3 Number of eyes with elevated IOP according to tampon-ade type and time of onset

	BSS	Air	SF6	C3F8	Oil	Total	Cumulative%
0–1 w	1	0	1	4	4	10	20.00%
1 w–1 m	2	0	0	12	10	24	68.00%
1 m–3 m	1	0	0	3	3	7	82.00%
4 m–6 m	0	0	0	0	2	2	86.00%
7 m–9 m	0	0	0	0	1	1	88.00%
10 m–12 m	0	0	0	3	3	6	100.00%
Total	4	0	1	22	23	50

Notes: Air, filtered air; oil, silicone oil.

Abbreviations: SF6, sulfur hexafluoride; C3F8, perfluoropropane; BSS, balanced salt solution; IOP, intraocular pressure; m, month; w, week.

Table 4 Treatment outcomes of IOP elevation according to tamponade type

	Drugs alone		Surgery		Drop treatment
	Temporary	Persistent	Complete success	Qualified success
BSS	2 (50.00%)	2 (50.00%)	0	0	0
SF6	1 (100%)	0	0	0	0
C3F8	15 (68.18%)	3 (13.63%)	1 (4.55%)	0	3 (13.63%)
Oil	3 (13.04%)	5 (21.74%)	4 (17.39%)	10 (43.48%)	1 (4.35%)
Total	21 (42.00%)	10 (20.00%)	5 (10.00%)	10 (20.00%)	4 (8.00%)

Notes: Results are presented as N (%). Oil, silicone oil.

Abbreviations: SF6, sulfur hexafluoride; C3F8, perfluoropropane; BSS, balanced salt solution; IOP, intraocular pressure.

Table 5 Outcomes of surgical procedures for the control of IOP

	Complete success		Qualified success		Failure
	N	%	N	%	N	%
Valve implantation	3	100	0	0	0	0
Silicone oil removal	1	8.33	10	83.33	1	8.33
Lensectomy	1	100	0	0	0	0

Abbreviation: IOP, intraocular pressure.