Visual prognosis and surgical timing of Ahmed glaucoma valve implantation for neovascular glaucoma secondary to diabetic vitrectomy

Table 3 Factors affecting central vision loss after Ahmed glaucoma valve implantation in Group 1

	Favorable visual outcome* (n = 9)	Unfavorable visual outcome (n = 7)	P-value
Age (years)	58.7 ± 11.4	58.0 ± 8.7	0.916†
Sex (M/F)	5/4	3/4	1.000‡
IOP (mmHg)
At the time of NVG diagnosis	41.0 ± 8.6	41.6 ± 7.8	0.874†
At the time of AGVI	41.4 ± 7.4	41.0 ± 7.5	0.791†
BCVA (LogMAR)
Before the diagnosis of NVG	0.74 ± 0.42	1.05 ± 0.55	0.238†
At the time of NVG diagnosis	2.23 ± 0.19	2.00 ± 0.23	0.032†
Early AGVI timing (%) (less than one week from NVG diagnosis)	7 (77.8)	1 (14.3)	0.041‡
No. of IOP-lowering medications	2.0 ± 0.94	2.3 ± 0.45	0.678†
AC paracentesis (%)	6 (66.7)	6 (42.9)	1.000‡
Anti-VEGF injections (%)	5 (62.5)	5 (86.7)	0.585‡
Add PRP (%)	0 (0)	1 (14.3)	0.438‡

*Favorable visual outcome : Comparing preoperative BCVA(sufficiently stable BCVA after the recovery from diabetic vitrectomy) and postoperative BCVA (the best result of the BCVA measurements during the one year follow-up period after AGVI), a favorable visual outcome was defined as a BCVA that deteriorated to less than 0.3 logMAR unit after AGVI.
† Calculated using an independent t-test and Mann Whitney test
‡ Calculated using a Chi-Square test and Fisher’s Exact test
Abbreviations: M, male; F, female; IOP, intraocular pressure; BCVA, best-corrected visual acuity; AGVI, Ahmed glaucoma valve implantation; NVG, neovascular glaucoma; AC, anterior chamber; Add PRP, additional pan-retinal photocoagulation
Group 1, Group of NVG patients who maintained an IOP of 30 mmHg or more before AGVI despite initial non-surgical treatment, including maximum tolerable medical treatment.

ISSN: 1471-2415