Advances in Clinical and Experimental Medicine

Title abbreviation: Adv Clin Exp Med
JCR Impact Factor (IF) – 1.736
5-Year Impact Factor – 2.135
Index Copernicus  – 168.52
MEiN – 70 pts

ISSN 1899–5276 (print)
ISSN 2451-2680 (online)
Periodicity – monthly

Download original text (EN)

Advances in Clinical and Experimental Medicine

2018, vol. 27, nr 1, January, p. 15–20

doi: 10.17219/acem/66806

Publication type: original article

Language: English

Download citation:

  • BIBTEX (JabRef, Mendeley)
  • RIS (Papers, Reference Manager, RefWorks, Zotero)

Comparison of polypropylene and silicone Ahmed® glaucoma valves in the treatment of neovascular glaucoma: A 2-year follow-up

Wojciech Lubiński1,A,C,E,F, Karol Krzystolik1,C,D, Wojciech Gosławski1,B, Leszek Kuprjanowicz1,B, Maciej Mularczyk2,C

1 Department of Ophthalmology, Pomeranian Medical University, Szczecin, Poland

2 Chair and Department of Human and Clinical Anatomy, Pomeranian Medical University, Szczecin, Poland


Background. Inflammation associated with biomaterials of Ahmed® glaucoma drainage devices may cause the formation of a capsule around the device and can thus have a significant influence on the level of intraocular pressure reduction.
Objectives. The objective of this study was to compare the clinical outcomes after the implantation of a polypropylene or silicone Ahmed® glaucoma valve in patients with neovascular glaucoma.
Material and Methods. In the study, 27 eyes with neovascular glaucoma (group 1) received silicon Ahmed® valves and 23 eyes (group 2) received polypropylene valves. The best corrected distance visual acuity (BCDVA), intraocular pressure (IOP) and number of anti-glaucomatous drugs were recorded preoperatively and during a follow-up period of 24 months after surgery. Success was defined by the following criteria: 1) intraocular pressure in the rage of 6–21 mm Hg; 2) IOP reduction of at least 30% relative to preoperative values. All complications were registered.
Results. One month postoperatively, the mean BCDVA increased significantly in both groups compared to preoperative values (p < 0.001). These values did not change during the 24 months of follow-up examinations. The probability of success defined by criterion 1 at 24 months of observation was 66.7% for silicone and 27.3% for propylene valves group (p < 0.007). According to criterion 2, the difference in success between the groups was not statistically significant. The total number of complications that occurred in both groups during the 24 months of follow-up examinations was similar, except for a higher occurrence of Tenon’s cyst formation in the group with a polypropylene valve (18% vs 35%; p < 0.04).
Conclusion. In patients with neovascular glaucoma, the implantation of a silicone valve is associated with a significantly higher probability of long-term reduction of IOP below 21 mm Hg and with a lower risk of valve encapsulation in comparison to polypropylene valves. The obtained results suggest that silicone Ahmed® valves are more effective in the treatment of patients with neovascular glaucoma.

Key words

inflammation, neovascular glaucoma, glaucoma drainage implants, biocompatible materials

References (22)

  1. Dessai MA, Gedde SJ, Feuer WJ, Shi W, Chen PP, Parrish RK 2nd. Practice interferences for glaucoma surgery: A survey of the American Glaucoma Society in 2008. Ophthalmic Surg Lasers Imaging. 2011;42:202–208.
  2. Prata JA, Mermoud A, LaBree L, Minckler DS. In vitro and in vivo flow characteristics of glaucoma drainage implants. Ophthalmology. 1995;102:894–904.
  3. Ayyala RS, Harman LE, Michelini-Norris B, et al. Comparison of different biomaterials for glaucoma drainage devices. Arch Ophthalmol. 1999;117:233–236.
  4. Ishida K, Netland PA, Costa VP, Shiroma L, Khan B, Ahmed II. Comparison of polypropylene and silicone Ahmed glaucoma valve. Ophthalmology. 2006;113:1320–1326.
  5. Mackenzie PJ, Schertzer RM, Isbister CM. Comparison of silicone and polypropylene Ahmed glaucoma valves: Two years follow-up. Can J Ophthalmol. 2007;42:227–232.
  6. Hinkle DM, Zurakowski D, Ayyala RS. A comparison of the polypropylene plate Ahmed glaucoma valve to the silicone plate Ahmed glaucoma flexible valve. Eur J Ophthalmol. 2007;17:696–701.
  7. Hayreh SS. Neovascular glaucoma. Prog Retin Eye Res. 2007;26:470–485.
  8. Sivak-Callcott JA, O’Day DM, Gass JD, Tsai JC. Evidence-based recommendations for the diagnosis and treatment of neovascular glaucoma. Ophthalmology. 2001;108:1767–1776.
  9. Tsai JC, Feuer WJ, Parrish RK 2nd, Grajewski AL. 5-Fluorouracil filtering surgery and neovascular glaucoma. Long-term follow-up of the original pilot study. Ophthalmology. 1995;102(6):887–892.
  10. Takihara Y, Inatani M, Fukushima M, Iwao K, Iwao M, Tanihara H. Trabeculectomy with mitomycin c for neovascular glaucoma: Prognostic factors for surgical failure. Am J Ophthalmol. 2009;147:912–918.
  11. Bai YJ, Li YQ, Chai F, et al. Comparison of FP-7 and S-2 Ahmed glaucoma valve implantation in refractory glaucoma patients for short-term follow-up. Chin Med J. 2011;124:1128–1133.
  12. Shen CC, Salim S, Du H, Netland PA. Trabeculectomy versus Ahmed glaucoma valve implantation in neovascular glaucoma. Clin Ophthalmol. 2011;5:281–286.
  13. Ayyala RS, Harman LE, Michelini-Norris B, et al. Comparison of different biomaterials for glaucoma drainage devices. Arch Ophthalmol. 1999;117(2):233–236.
  14. Ayyala RS, Michelini-Norris B, Flores A, Haller E, Margo CE. Comparison of different biomaterials for glaucoma drainage devices: Part 2. Arch Ophthalmol. 2000;118(8):1081–1084.
  15. Schwartz KS, Lee RK, Gedde SJ. Glaucoma drainage implants: A critical comparison of types. Curr Opin Ophthalmol. 2006;17:181–189.
  16. Heuer DK, Lloyd MA, Abrams DA, et al. Which is better? One or two? A randomized clinical trial of single-plate versus double-plate Molteno implantation for glaucomas in aphakia and pseudophakia. Ophthalmology. 1992;99:1512–1519.
  17. Britt MT, LaBree LD, Lloyd MA, et al. Randomized clinical trial of the 350-mm2 versus the 500-mm2 Baerveldt implant: Longer term results: Is bigger better? Ophthalmology. 1999;106(12):2312–2318.
  18. Kyung MK, Young HH, Jong JJ, Yong HS, Hwang KK. Comparison of the outcome of silicone Ahmed glaucoma valve implantation with a surface area between 96 and 184 mm2 in adult eyes. Korean J Ophthalmol. 2013;27(5):361–367.
  19. Lloyd MA, Baerveldt G, Fellenbaum PS, et al. Intermediate-term results of a randomized clinical trial of the 350- versus the 500-mm2 Baerveldt implant. Ophthalmology. 1994;101:1456–1463.
  20. Christakis PG, Kalenak JW, Zurakowski D, et al. The Ahmed versus Baerveldt study: One-year treatment outcomes. Ophthalmology. 2011;118(11):2180–2189.
  21. Christakis PG, Tsai JC, Kalenak JW, et al. The Ahmed versus Baerveldt study: Three-year treatment outcomes. Ophthalmology. 2013;120(11):2232–2240.
  22. Taglia DP, Perkins TW, Gangnon R, Heatley GA, Kaufman PL. Comparison of the Ahmed glaucoma valve, the Krupin eye valve with disk, and the double-plate Molteno implant. J Glaucoma. 2002;11(4):347–353.