Changes in macular thickness after trabeculectomy with or without adjunctive 5-fluorouracil

Abstract

Conflict of interest.None of the authors have any conflict of interest to declare, financial or otherwise. No financial or other support was received for the study.Background.The aim of the study was to assess changes in macular thickness after trabeculectomy in respect to the use of 5-fluorouracil (5-FU) as well as to analyse possible associations between the postoperative changes in macular thickness and intraocular pressure (IOP).Materials and methods.The prospective observational study included 106 eyes (100 patients) with glaucoma who underwent trabeculectomy with or without 5-FU. Subsequently 5-FU needling was performed if failure of the filtrating bleb occurred. Macular thickness and the IOP were evaluated before, one week, and six months after the surgery. The mean and sectoral macular thickness was assessed using spectral domain optical coherence tomography.Results.The mean (±SD) IOP reduced from 27.71 (±6.88) mmHg at baseline to 18.3 (±8.1) mmHg one week (p < 0.001) and 15.1 (±7.6) mmHg six months (p < 0.001) after trabeculectomy. One week postoperatively, the mean macular thickness increased from 285.19 (±15.98) μm to 288.9 (±16.31) μm (p < 0.001); macular thickening was significant in all subfields (p < 0.001) and correlated positively with IOP reduction (rho = 0.312, p = 0.001 for central subfield). After six months, macula remained thicker only at the central and inner nasal subfields (p < 0.05). The changes in macular thickness were not affected by the use of 5-fluorouracil.Conclusions.Trabeculectomy may induce a slight macular thickening which is more pronounced in the early postoperative period. The IOP reduction plays an important role in this process and is associated with thicker postoperative macula. However, the use of adjunctive 5-FU has no influence on macular thickness after glaucoma surgery despite its potential hypotonic, inflammatory and cytotoxic effects.

Structural Changes in the Optic Disc and Macula Detected by Swept-Source Optical Coherence Tomography After Surgical Intraocular Pressure Reduction in Patients with Open-Angle Glaucoma

“…In addition, changes in the relationship between capillary pressure and interstitial fluid pressure may occur after IOP change. 18,22 In this study, we did not observe any significant change in the mean and sectorial RNFL thickness measured by SS-OCT with surgical IOP reduction. This is in agreement with the findings of previous reports that used scanning laser polarimetry, TD-OCT and SD-OCT. 13,14,23,24 With SD-OCT, Gietzelt et al 13 did not observe significant changes in mean and sectorial RNFL thicknesses between baseline and follow up at 3, 6 and 12 months after trabeculectomy.…”

“…Kadziauskienė et al also observed a significant increase in mean macular thickness and nine subfields defined by the Early Treatment Diabetic Retinopathy Study (ETDRS) in 106 eyes after 1 week of trabeculectomy. 18 After six months, macula remained thicker only at the central and inner nasal subfields. In our study, the analysis conducted using the SS-OCT commercial software suggests that parameters of the inner macular layers relevant to glaucoma such as total GCL+ and total GCL++, may increase after surgery.…”

“…In addition, changes in the relationship between capillary pressure and interstitial fluid pressure may occur after IOP change. 18 , 22…”

“…13,14 There is also evidence of macular thickness increase measured by TD-OCT and SD-OCT associated with IOP reduction after uncomplicated glaucoma filtering surgery. 17,18 However, no information is available about how inner macular layers relevant to glaucoma are affected by this intervention or how their changes are related to changes in topographic parameters.…”

Early Macular Thickness Changes after Trabeculectomy and Combined Phaco-Trabeculectomy

“…Central macular thickness changes following intraocular surgeries have been shown to impair visual outcomes even in uncomplicated cases. 1 2 3 4 5 Acute reduction of intraocular pressure (IOP) after glaucoma filtering surgery could result in reversible central macular thickening and retinal changes. 5 6 7 8 9 Such macular thickening after glaucoma filtering surgery could be a physiological reaction to the stress of the retina after a sudden reduction of IOP.…”