The effects of sleep disorders on the human health have been widely documented. Besides the brain, research has suggested that sleep disorders can also influence other extracerebral physiology such as the eyes.

By Dr Desmond Quek
Glaucoma Department
General Cataract and Comprehensive Ophthalmology Department
Singapore National Eye Centre

Sleep disorders have been reported to be associated with eye conditions such as floppy eyelid syndrome (eyelids that are easily everted), ischemic optic neuropathy (loss of vision due to decreased blood flow to the optic nerve) and glaucoma (buildup of pressure inside the eye which can cause optic nerve damage).

Some of these conditions, such as glaucoma, can potentially cause irreversible blinding.

One of the most prevalent sleep disorders is obstructive sleep apnea (OSA). It occurs when the throat intermittently relaxes and blocks the airway, causing breathing to repeatedly stop and start during sleep.

While the association between these eye conditions and OSA are clear, the reasons for this connection are not yet understood.

One possibility is that OSA compromises blood flow to the optic nerve. This creates a transient drop in oxygen supply and increases resistance to blood flow, thus damaging the optic nerve.

In collaboration with the Sleep Disorders Unit at SGH, SNEC conducted a prospective study examining the prevalence of glaucoma in patients with OSA. A hundred patients with moderate to severe OSA were recruited.

We performed comprehensive ophthalmic examinations using advanced imaging techniques to detect glaucoma even in its early stages. The results of this study will be shared at the upcoming ASEAN Sleep Congress.

We are also looking at recruiting individuals with no or mild OSA to form a control group so that we can make meaningful comparisons. We hope to compare eye pressures, visual field results and imaging studies of both groups and determine if the OSA patients are indeed more likely to have glaucoma.

I hope that this study will encourage clinicians to alert OSA patients of the associations between OSA and open-angle glaucoma. This will help to raise awareness of the issue and encourage treatment for those who need it.

Glaucoma, if detected and treated in its early stages, can prevent irreversible blindness. I hope to further explore if the treatment of OSA prevents the development or retards the progression of glaucoma in patients with OSA.


Catch Dr Desmond Quek as he shares more on sleep-disordered breathing and ophthalmic complications at the 3rd ASEAN Sleep Congress happening on 20 - 22 November 2015.

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