The eye and sleep

[Ocular disease in sleep apnea syndrome]

Sleep apnea syndrome is characterised by recurrent episodes of partial or complete upper airway flow interruption during sleep. In the last twenty years, the relationship of sleep apnea with cardiovascular disease has been recognised. More recently, several ocular disorders have been associated with sleep apnea syndrome, including floppy eyelid syndrome, glaucoma, non-arteritic ischemic optic neuropathy and papilledema. Based on the published evidence, we discuss these associations along with the possible pathophysiological mechanisms and clinical management. It is needed that the ophthalmologist, the primary care physician and the sleep physician are aware of this association so that both sleep disorders and the related ophthalmologic disorders can be better diagnosed and treated.

Impact of floppy eyelid syndrome in ocular surface and dry eye disease

Floppy eyelid syndrome (FES), a clinically recognized condition of lax and rubbery eyelids, is commonly under-diagnosed. It is associated with chronic papillary conjunctivitis and is often, although not always associated with obesity and obstructive sleep apnea. Symptoms of FES mimic those of ocular surface disease; indeed FES itself can contribute to ocular surface damage. Diagnostic signs of FES can include foreign body sensation, ocular discharge, injection, and eyelid and eyelash ptosis. Palliative topical measures may be inadequate for symptomatic relief necessitating surgical eyelid repair.

Sleep disorders and the eye

During the past decade, associations between sleep disorders and certain ophthalmologic disorders have been increasingly recognized. To review the literature on these important associations, we conducted a PubMed search using combinations of the following terms: sleep disorders, sleep apnea, circadian rhythm disorder, continuous positive airway pressure, eye disease, floppy eyelid syndrome, glaucoma, ischemic optic neuropathy, papilledema, nocturnal lagophthalmos, and vision loss. We limited our search to articles published in English that involved human participants. All available dates were included. One of the most common sleep disorders, obstructive sleep apnea, has been associated with a variety of eye diseases, including glaucoma, nonarteritic anterior ischemic optic neuropathy, floppy eyelid syndrome, papilledema, and continuous positive airway pressure-associated eye complications. Nocturnal lagophthalmos manifests during sleep and is defined as the failure to fully close the eyelids at night. Finally, blindness is associated with increased risk of circadian rhythm disorders. On the basis of the existing published literature, we discuss these rarely recognized associations, potential pathophysiologic mechanisms, and the effect these associations have on the clinical management of patients. The knowledge of these associations is important for the primary care physician, ophthalmologist, and sleep physician so that underlying sleep disorders or ophthalmologic disorders can be detected.

Floppy eyelid syndrome

PURPOSE OF REVIEW

Although floppy eyelid syndrome causes significant ocular symptoms and morbidity, the condition is often underdiagnosed. This review will highlight diagnostic features of the condition, emphasizing recent advances in the understanding of its pathophysiology. Current therapeutic strategies and surgical techniques are discussed.

RECENT FINDINGS

Current concepts regarding the underlying pathophysiology of floppy eyelid syndrome revolve around upregulation of elastin degrading enzymes and mechanical factors. Together, these forces cause instability of the eyelid scaffold, resulting in eyelid malposition and ocular symptoms. Newer surgical treatments aim to preserve tarsus to improve eyelid stability and position.

SUMMARY

Floppy eyelid syndrome--an underdiagnosed condition--produces significant ocular morbidity. Symptoms range from occasional redness and irritation to corneal ulcer. Diagnosis is based on ocular signs, including easy or spontaneous eversion of the upper eyelids in conjunction with conjunctivitis and keratitis. The condition, associated with body mass index and obstructive sleep apnea, should be suspected in any obese patient with a chronic red and tearing eye. Treatment consists of supportive measures such as ocular lubrication, eyelid taping or a shield, and surgery to address horizontal laxity and redundant eyelid tissues.

The eye and sleep apnea

Several eye disorders have been found in association with obstructive sleep apnea (OSA). This paper reviews the current state of knowledge of eye disorders associated with OSA. OSA is associated with a number of eye disorders including floppy eyelid syndrome (FES), optic neuropathy, glaucoma, non-arteritic anterior ischemic optic neuropathy and papilledema secondary to raised intracranial pressure. FES patients have a very high incidence of OSA and a causal relationship may exist, but amongst patients with OSA, FES is uncommon but commoner than in the general population. Treatment of OSA may help floppy eyelid syndrome, halt progression of associated glaucoma or optic neuropathy, and reduce intracranial pressure in patients with associated papilledema. Sleep apnea patients should be asked about ocular symptoms and appropriately examined or referred for assessment as some of the associated eye disorders may permanently impair vision. Ophthalmologists should be aware of the association of sleep apnea with these eye disorders and consider referral to a sleep physician for investigation and possible treatment.

Obesity and eye diseases

The prevalence of obesity has reached epidemic proportions in many countries. Although its impact on overall health is well documented, less is known about the ocular manifestations of obesity. Among different eye diseases, obesity has been linked with age-related cataract, glaucoma, age-related maculopathy, and diabetic retinopathy. Numerous population-based and prospective studies support an association between obesity and risk of age-related cataract. However, the nature and strength of these associations, particularly with the different cataract subtypes, remains to be determined. There is strong evidence that obesity is associated with elevated intraocular pressure, but there is no convincing data to support a more direct association between obesity and glaucomatous optic neuropathy. Studies to date have not found a consistent pattern of association between obesity and risk of age-related maculopathy or diabetic retinopathy. Thus, although obesity may be a risk factor for many ocular conditions, the present literature is inadequate to establish any convincing associations. Furthermore, whether weight loss reduces the risk of eye diseases remains unresolved. Because of the potential public health impact of obesity, there is a greater need to understand its ocular effects.

Plasma Leptin Levels in Patients with Floppy Eyelid Syndrome

PURPOSE

To determine the range of plasma leptin levels in patients with floppy eyelid syndrome (FES).

METHODS

This was a retrospective, noninterventional case series of 11 patients with FES. Charts were reviewed for patient age, sex, plasma leptin level, body mass index (BMI), presence or absence of obstructive sleep apnea (OSA) and diabetes mellitus, and any treatments for OSA.

RESULTS

Charts of 11 patients were reviewed (10 male, 1 female). Plasma leptin levels were elevated in 7 of 11 patients (64%). Mean plasma leptin concentration was 49.5 ng/ml in male patients (range, 5 to 120 ng/ml) compared with a normal range of 1 to 35 ng/ml. Plasma leptin level in the female patient was 180 ng/ml (normal range, 4 to 72 ng/ml). Five patients had a known diagnosis of OSA. Four of these patients received continuous positive airway pressure during leptin level measurement. Plasma leptin levels averaged 110.0 ng/ml in the continuous positive airway pressure group. Average BMI was 37.4 kg/m (range, 24.9 to 57.1 kg/m). All patients with elevated leptin levels had a high BMI.

CONCLUSIONS

Patients with FES demonstrate elevated plasma leptin levels, which correlate with BMI. Hyperleptinemia may play a role in the pathogenesis of FES.

Nocturnal Lagophthalmos: An Overview and Classification

Nocturnal lagophthalmos is the inability to close the eyelids during sleep. Lagophthalmos is associated with exposure keratopathy, poor sleep, and persistent exposure-related symptoms. There are a variety of causes of lagophthalmos, grouped as proptosis/eye exposure etiologies and palpebral insufficiency etiologies. Although obvious lagophthalmos is usually detected, it is sometimes difficult to recognize obscure lagophthalmos, due either to eyelash obstruction or overhang of the upper lid anterior and inferior to the most superior portion of the lower lid in a closed position. We present a novel classification system and illustrations of obvious and obscure lagophthalmos. A diagnosis can usually be made with a focused history and slit lamp examination. Treatment is multipronged and may include minor procedures or ocular surgery to correct the lid malposition; natural, topical or oral agents; and punctal plugs to manage ocular surface effects. Correct and timely diagnosis allows greater opportunity for relief of patient suffering and prevention of severe ocular surface pathology, as well as educated planning for future ocular surgical procedures.