Abstract
Purpose :
Trabeculectomy surgery could affect ocular surface disease(OSD) in several ways, through cessation of long term glaucoma eyedrops, exposure to operative mitomycin C and post-operative eyedrops including corticosteroids and aminoglycosides; and reduction in eyelid hygiene measures. Previously we showed the relevance of tear eicosanoids in OSD. Here, we aim to evaluate changes of these lipids post-trabeculectomy.
Methods :
Patients undergoing trabeculectomy were prospectively evaluated and had tear collected using schirmer’s strips, preoperatively and postoperatively at 0.5, 1.0 and 3.0 years. Forty eicosanoids were evaluated with mass spectrometry, quantified with lipid standards, and concentrations normalized to 1 mm of schirmer.
Results :
The normalized concentrations of 38 eicosanoids were between 0.1-5.0 ng/mL, whereas docosahexaenoic acid(DHA) and eicosapentaenoic acid(EPA) ranged up to a few hundred ng/mL. All lipids showed a right-skewed distribution. The concentrations of eicosanoids, except DHA, EPA and thromboxane(TX)B1, showed reduction after surgery. At the last visit, these lipids were significantly reduced by 1/3 to half, compared to pre-operative values: 8-hydroxyeicosatetraenoic acid (HETE), 15-HETE, 15-oxo-eicosatetraenoic(ETE), 11-HDoHE, 17-hydroxydocosahexaenoic acid(HDoHE) and 20-hydroxy-leukotriene(OH LT)B4. To examine collective changes of lipids, clustering analysis revealed 10 groups of lipids consistent with known metabolic pathways.
An increase in the level of 2,3-dinor-11prostaglandin(PG)F2α between 0-0.5 year was associated with inferior corneal staining at 0.5 year, whereas 20-HDoHE was significantly lower in these cases, compared to those without corneal staining at 0.5 year. None of the lipids were correlated to tear osmolarity at 0.5 year (r<0.35, p>0.05). In 14 patients who required post-operative needling, six eicosanoids were found to be significantly higher at 1.0 year compared to non-needled patients.
Conclusions :
In this 3-year study, trabeculectomy reduced the tear level of pro-inflammatory eicosanoids. Patients who required needling of the bleb to maintain surgical success may have a chronic underlying inflammatory process associated with fibrosis.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.