Evaluation of the effects of pseudoexfoliation and DRY eye on the anterior and posterior segment findings

Ferişte ARAS KALAY, Evaluation of the Effects of Pseudoexfoliation and Dry Eye on the Anterior and Posterior Segment Findings. Expertise Thesis, Bolu, 2020 Pseudoexfoliation syndrome (PES) is a clinically diagnosed disease involving the anterior and posterior segment of the eye and defined by dandruff-like materials accumulated on the anterior surface of the lens and iris, in the anterior chamber angle (ACA), on the anterior surface of corneal endothelium and vitreous. This material is produced in nonpigmented ciliary epithelial cells, iris pigment epithelial cells, pre-equatorial lens epithelial cells, vascular endothelium, trabecular mesh and smooth muscle cells. It is mostly observed in older aged population and varied with the races. Pseudoexfoliation syndrome can result in the complications such as the intraocular pressure (IOP) increase and glaucoma, zonular dehiscence, phacodonesis, lens subluxation, capsular rupture or vitreous loss during the cataract surgery, blood-aqueous barrier dysfunction, corneal endothelial decompensation, iris-derived hemorrhage, postoperative inflammation and early secondary cataract. Preocular tear film layer (TFL) is a hydrated mucus gel containing soluble antimicrobial proteins and growth factors that protect and support the ocular surface. Dry eye (DE) is a TFL disorder that develops by an insufficient amount of tear or excessive evaporation of the tear and causes an ocular discomfort, dryness, itching, burning, pain and foreign body sensation in the eye. In some studies, the pseudoexfoliation material (PEM) has been reported to lead to decreased secretion and disrupted stability of the tear. In the literature, although there are many studies on the changes that PES causes in the anterior segment of the eye and the effect of this material on tear functions, there is no study that reveals the changes that this relationship causes in the parameters of the anterior and posterior segments. In our study, 160 eyes of 80 individuals who applied to our clinic for routine eye examination were evaluated in terms of PES and DA. Detailed anamnesis was obtained from all patients and detailed eye examinations (Visual acuity assessment, Schirmer I test, IOP measurement, biomicroscopic examination of the anterior and posterior segments, optical biometry, optical coherence tomography (OCT) and Pentacam-HR imaging) were performed. The cases were divided into two subgroups as PES (-) and PES (+), and 2 subgroups as DE (-) and DE (+). A statistically significant negative correlation was found between the axial length (AL), ACA and choroidal thickness (CT) parameters and the presence of PES (r= -0,176, -0,188 and -0,332, p= 0,026, 0,017 and <0,001, respectively), while a significant positive correlation was detected between AL values and ACA and anterior chamber depth (ACD) parameters (r= 0,233 and 0,267, p= 0,003 and 0,001, respectively). A significant negative correlation was observed between IOP and AL, ACA and ACD (r= -0,186, -0,233 and -0,196, p= 0,018, 0,003 and 0,013, respectively), as well as a significant negative correlation between age and ACA and CT values (r= -0,189 and -0,389, p= 0,017 and <0,001, respectively). When the presence of DE and demographic and ophthalmological data were compared, no significant relationship was observed. The addition of detailed anterior and posterior segment evaluation to the ophthalmological examination in the clinical practice may be helpful in understanding the pathophysiology and prognosis of PES, as well as having vital importance in the early diagnosis and treatment of concomitatnt diseases that may occur. Key Words: Anterior segment, Dry eye, Optical biometry, Optical coherence tomography, Pentacam-HR, Posterior segment, Pseudoexfoliation Syndrome.