Mahla Shadravanmshadravan.oph@gmail.comClinical Research Development Unit, Shafa Hospital, Kerman University of Medical Sciences, Kerman,

Shahin Yazdanishahinyazdani@yahoo.comOcular Tissue Engineering Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran,

Bahareh Kheiribahareh.kheiri@gmail.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran,

Farideh Sharifipoursharifipourf@yahoo.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran,

Azadeh Doozandehazadeh.doozandeh@gmail.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran,

Mohammad Mehdi Hatamidrmehdihatami@gmail.comOphthalmic Research Center, Research Institute for Ophthalmology and Vision Science, Shahid Beheshti University of Medical Sciences, Tehran,

Neda Einollahieinollahi006@gmail.comDepartment of Ophthalmology, Labbafinejad Medical Center, Shahid Beheshti University of Medical Sciences, Tehran,

Purpose: Eyes with pseudoexfoliation demonstrate fragile intraocular structures. The current study evaluated conjunctival thickness in pseudoexfoliation eyes as compared to a control group.
Methods: In this cross-sectional study, patients with pseudoexfoliation and an age-matched control group underwent measurement of bulbar conjunctival thickness in the superior and temporal quadrants, 1, 2, and 3 mm posterior to the limbus using anterior segment OCT.
Results: A total of 140 eyes of 140 subjects including 68 eyes of 68 patients with pseudoexfoliation and 72 eyes of 72 control subjects without pseudoexfoliation were studied. Both study groups were divided into two subgroups – those using glaucoma drops versus medication-free eyes. Total conjunctival thickness in pseudoexfoliation eyes was significantly lower than control eyes across all comparisons. Conjunctival thickness in the superior quadrant 1, 2, and 3 mm from the limbus was 177.62 ± 41.30, 235 ± 48.41, and 231.40 ± 49.81 μm, respectively in the pseudoexfoliation group versus 207.49 ± 48.92, 265.67 ± 52.66, and 262.74 ± 59.43 μm in the control group (P <0.001, <0.001, and 0.001, respectively). In the temporal quadrant, conjunctival thickness 1, 2, and 3 mm from the limbus was 193.62 ± 46.97, 198.19 ± 54.67, and 178.59 ± 57.90 μm, respectively in the pseudoexfoliation group versus 213.76 ± 47.06, 224.50 ± 56.24, and 210.26 ± 63.70 μm in the control group (P = 0.012, 0.006, and 0.003, respectively).
Conclusion: Conjunctival thickness was significantly less in pseudoexfoliation eyes than an age-matched control group which supports clinical observations of thinner and more fragile conjunctiva in these eyes with implications for glaucoma surgery.

Keywords: Anterior Segment Optical Coherence Tomography, Conjunctival Thickness, Pseudoexfoliation

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