Writtle University College and ARU have merged. Writtle’s full range of college, degree, postgraduate and short courses will still be delivered on the Writtle campus. See our guide to finding Writtle information on this site.

The effects of environmental stress

One woman testing another on photo-slitlamp equipment in the Vision and Eye Research Institute's controlled environment chamber

The effect of environmental stress on patients with glaucoma (ENCOGLAP)

It is well known that some glaucoma patients' eyes feel irritated when using glaucoma eye drops. We examine whether environmental conditions increase this discomfort – and consequently increases non-adherence to the glaucoma treatment.

ENCOGLAP (Environmental Conditions in Glaucoma Patients) is an EU H2020 MSCA IF funded project. We evaluate, using a Controlled Environmental Chamber, the effects of environmental stress on the ocular surface in glaucoma patients using glaucoma eye drops compared to healthy subjects.

We are also evaluating objective optical quality using the OQAS and performing several tests used in clinical practice for dry-eye disease diagnosis, such as the Schirmer test, Phenol red test, FBUT or tear osmolarity. In addition, we use some techniques that are still under research, including ocular thermography, blinking rate assessment, and a new device developed in our laboratory to evaluate tear stability.

Subjective questionnaires are used to assess subjective adherence to glaucoma treatment, and to evaluate if the subjective symptoms of dryness and discomfort may enhance or decrease depending on the conditions that the subjects are exposed to.

The effect of environmental stress on the diabetic cornea

This PhD study is investigating the effects of environmental factors on the ocular surface.

There are few studies examining how environmental conditions may cause anterior ocular changes in patients with diabetes. This research investigates the influence of environmental stress on the tear film and ocular surface in diabetes.

The effect of environmental stress on contact lens wear

Contact lens wearers frequently report symptoms of discomfort and dryness, this being among the major causes of drop out.

We use an environmental chamber to assess how being exposed to different everyday environments affects the ocular surface, and the subjective symptoms when people are wearing different types of contact lenses.

We explore the effect of low and high humidity on the ocular comfort of the contact lenses wearers, using common clinical tests including FBUT or assessing ocular hyperaemia, as well new methods including blinking rate and ocular surface temperature.

We also evaluate how different environmental conditions affect the optical quality of contact lens wearers using the OQAS, a device that allows measuring the scatter of the eye, which is affected by the tear stability.

Professor Shahina Pardhan
Dr Juan Tabernero
Dr Nery García-Porta
Dr Raju Sapkota
Dr Lavanta Farouk

Recent publications

Tabernero, J., García-Porta, N., Artal, P., Pardhan, S. 2021. Intraocular scattering, blinking rate and tear film osmolarity after exposure to environmental stress. TVST. doi: 10.1167/tvst.10.9.1

Otero, C., García-Porta, N., Tabernero, J., Pardhan, S., 2019. Comparison of different smartphone cameras to evaluate conjunctival hyperaemia in normal subjects. Scientific Reports, 9(1). doi: 10.1038/s41598-018-37925-5

García-Porta, N., Gantes-Nuñez, F. J., Tabernero, J., Pardhan, S., 2019. Characterization of the ocular surface temperature dynamics in glaucoma subjects using long-wave infrared thermal imaging. Journal of the Optical Society of America A: Optics and Image Science, and Vision, 36(6), pp. 1015-1021. doi: 10.1364/JOSAA.36.001015