Acta Scientific Ophthalmology (ASOP)

Research Article Volume 3 Issue 1

The Correlation Between Intraocular Pressure Reduction and Changes in Optic Nerve Head, Retinal Nerve Fibre Layer and Visual Fields in Open Angle Glaucoma Following Filtration Surgery

Vinod Sharma1, Yash Pal Sharma2, Mohan Lal Pandey3*, Rakhi Sharma4, Vinay Gupta5 and Ram Lal Sharma6

1Associate Professor, Ophthalmology, Indira Gandhi Medical College, Shimla, Hp, India
2Resident Ophthalmology, Ophthalmology, Indira Gandhi Medical College, Shimla, Hp, India
3Professor Ophthalmology, Maharishi Markandeshwar Institute of Medical Sciences and Research, Mullana, Ambala, India
4Medical Officer, State Health Directorate, Shimla, Hp, India
5Assistant Professor, Ophthalmology Indira Gandhi Medical College, Shimla, Hp, India
6Professor Ophthalmology, Indira Gandhi Medical College, Shimla, Hp, India

*Corresponding Author: Mohan Lal Pandey, Professor Ophthalmology, Maharishi Markandeshwar Institute of Medical Sciences and Research, Mullana, Ambala, India.

Received: December 17, 2019; Published: December 27, 2019

×

Abstract

Aim:To study the correlation between intraocular pressure reduction and changes in structural (optic nerve head and nerve fibre layer) and functional (visual fields) parameters in open angle glaucoma patients following trabeculectomy.

Materials and Methods:A prospective, interventional study (n = 40) was done. Patients with COAG between 50 - 80 years with well documented glaucoma progression were included in the study. Patients with unreliable visual fields (fixation loss > 20%, false positive > 15%, and false negative > 33%), OCT images with less than 90% satisfactory A-scan or a signal-to-noise ratio of < 25 dB were excluded. Significant differences in mean test values over 12-months after intervention were evaluated with repeated measure ANOVA (analysis of variance). Logistic regression analysis was performed to study the effect of independent variables (age, gender, IOP reduction, duration of IOP control, change in rim area and rim volume) on dependent variables (RNFL thickness, mean sensitivity and mean deviation, respectively).

Results:Repeated measure ANOVA revealed a significant increase (P < 0.01) in rim area at all time points. There was a significant reduction in IOP at 1-month postoperative followed by slight paradoxical rise at 3 months. Significant changes in RNFL thickness were observed at 3, 6 and 12 months, respectively. On regression analysis, there was structural and functional correlation (IOP and RNFL thickness and rim area and mean deviation). There was 0.4microns change in RNFL thickness for 1mm of IOP reduction. Age (OR = 1.2, 95%CI, 0.89 - 1.34), gender (OR = 3.4, 95%CI, 507- 42.4), change in IOP (OR = 1.9, 95% CI, 1.2 - 32.8) and change in rim area (OR = 2.5, 95%CI, 0.25 - 29) significantly influenced change in RNFL thickness. Change in rim area exhibited higher odds (OR = 2.8) in causing change in mean deviation.

Conclusion:Despite a significant correlation between IOP reduction and RNFL thickness and change in mean deviation and rim area, lowering of IOP by surgical intervention may variably influence structural and functional parameters in glaucoma; these changes may depend on several factors like age, gender, the height and the amount of IOP reduction, the stage of glaucoma and follow up duration.

Keywords:Intraocular Pressure; Optic Nerve Head; Retinal Nerve Fibre Layer Thickness; Regression Analysis Trabeculectomy

×

References

  1. Naito T., et al. “Effect of trabeculectomy on visual field progression in Japanese progressive normal-tension glaucoma with intraocular pressure < 15 mmHg”. Plos one 12.8 (2017): e0184096.
  2. Wu SC., et al. “Reversal of optic disc cupping after trabeculotomy in primary congenital glaucoma”. Canadian Journal of Ophthalmology 37.6 (2002): 337-341.
  3. Chang PT., et al. “Effect of lowering intraocular pressure on optical coherence tomography measurement of peripapillary retinal nerve fibre layer thickness”. Ophthalmology 114.12 (2007): 2252-2258.
  4. Figus M., et al. “Short-term changes in the optic nerve head and visual field after trabeculectomy”. Eye (Lond) 25.8 (2011):1057-1063.
  5. Tsai CS., et al. “Visual field global indices in patients with reversal of glaucomatous cupping after intraocular pressure reduction”. Ophthalmology 98.9 (1991): 1412-1419.
  6. Kotecha A., et al. “More Flow Study Group. Optic disc and visual field changes after trabeculectomy”. Investigative Ophthalmology and Visual Science 50.10 (2009): 4693-4699.
  7. Tsai CS., et al. “Visual field global indices in patients with reversal of glaucomatous cupping after intraocular pressure reduction”. Ophthalmology 98.9 (1991):1412-1419.
  8. Rath EZ., et al. “Relationship between optic disc cupping change and intraocular pressure control in adult glaucoma patients”. Graefe's Archive for Clinical and Experimental Ophthalmology 234.7 (1996): 434-439.
  9. Meirelles SH., et al. “Evaluation of the factors associated with the reversal of the disc cupping after surgical treatment of childhood glaucoma”. Journal of Glaucoma 17.6 (2008): 470-473.
  10. Ely AL., et al. “Cupping reversal in pediatric glaucoma--evaluation of the retinal nerve fibre layer and visual field”. American Journal of Ophthalmology 158.5 (2014): 905-915.
  11. Xu G., et al. “Optic nerve head deformation in glaucoma: the temporal relationship between optic nerve head surface depression and retinal nerve fiber layer thinning”. Ophthalmology 121.12 (2014): 2362-2370.
  12. Chang PT., et al. “Effect of lowering intraocular pressure on optical coherence tomography measurement of peripapillary retinal nerve fiber layer thickness”. Ophthalmology 114 (2007): 2252-2258.
  13. Saif MY., et al. “Optical coherence tomography (OCT) changes after achieving target intraocular pressure”. Delta Journal of Ophthalmology 18 (2017): 170-175.
  14. Yamada N., et al. “Changes in the nerve fibre layer thickness following a reduction of intraocular pressure after trabeculectomy”. Journal of Glaucoma 9.5 (2009): 371-375.
  15. Raghu N., et al. “Effect of trabeculectomy on RNFL thickness and optic disc parameters using optical coherence tomography”. Eye (Lond) 26.8 (2012):1131-1137.
  16. Baumane K., et al. “The Effect of Glaucoma Filtration Surgery on Structural and Functional Eye Parameters in a Short-Term Study. Proceedings of the Latvian Academy of Sciences”. Section B. Natural, Exact, and Applied Sciences 71.1-2 (2017): 27-32.
  17. Waisbourd M., et al. “Reversible structural and functional changes after intraocular pressure reduction in patients with glaucoma”. Graefe's Archive for Clinical and Experimental Ophthalmology 254.6 (2016): 1159-1166.
  18. Lesk MR., et al. “Reversal of optic disc cupping after glaucoma surgery analyzed with a scanning laser tomography”. Ophthalmology 106.5 (1991):1013-1018.
×

Citation

Citation: Mohan Lal Pandey., et al. “The Correlation Between Intraocular Pressure Reduction and Changes in Optic Nerve Head, Retinal Nerve Fibre Layer and Visual Fields in Open Angle Glaucoma Following Filtration Surgery”.Acta Scientific Ophthalmology 3.1 (2020): 03-08.



Member In


News and Events


  • Certification for Review
    Acta Scientific certifies the Editors/reviewers for their review done towards the assigned articles of the respective journals.
  • Submission Timeline for March Issue
    The last date for submission of articles for regular Issues is April 10, 2020.
  • Publication Certificate
    Authors will be issued a "Publication Certificate" as a mark of appreciation for publishing their work.
  • Best Article of the Issue
    The Editors will elect one Best Article after each issue release. The authors of this article will be provided with a certificate of “Best Article of the Issue”.
  • Welcoming Article Submission
    Acta Scientific delightfully welcomes active researchers for submission of articles towards the upcoming issue of respective journals.
  • Contact US