This is an interesting look at ocular surface disease as associated with floppy eyelid syndrome (FES), which is more common in people with sleep apnea. They're suggesting people with symptomatic FES be checked out for sleep apnea.

But... look out for the flip side, which is that CPAP masks for sleep apnea treatment often cause dry eye symptoms by blowing air into the eyes, which is why Quartz and Onyix silicone eye shields were invented (though they are now also used widely for dry eye, lagophthalmos etc).

Ocular surface assessment in patients with obstructive sleep apnea-hypopnea syndrome.
PURPOSE:
The aim of this study was to assess the correlation between ocular surface changes and disease severity in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).
METHODS:
Two hundred eighty patients with OSAHS were compared with respect to the presence of a floppy eyelid syndrome (FES), Ocular Surface Disease Index (OSDI) questionnaire, the corneal fluorescein staining stages, the Schirmer I test, and tear film break-up time (TBUT) values.
RESULTS:
Based on the apnea-hypopnea index, the presence of FES was detected at the following rates: 23.1 % in non-OSAHS group (A), 41.7 % in mild group (B), 66.7 % in moderate group (C), and 74.6 % in severe group (D); severe and moderate stage of FES was found in groups C and D and mild stage of FES in group B (p < 0.01). OSDI questionnaire values were as follows: group A, 12.57 ± 17.64; group B, 22.90 ± 16.78; group C, 45.94 ± 22.03; and group D, 56.68 ± 22.85(p < 0.01). Schirmer values were as follows: group A, 10.76 ± 3.58 mm; group B, 9.83 ± 2.53 mm; group C, 7.73 ± 2.42 mm; and group D, 6.97 ± 2.15 mm (p < 0.01). The TBUT values were as follows: group A, 10.53 ± 3.64 s; group B, 9.46 ± 2.40 s; group C, 7.29 ± 2.13 s; and group D, 6.82 ± 2.20 s (p < 0.01). Corneal staining scores are as follows: 0.26 ± 0.60 in group A, 0.40 ± 0.71 in group B, 0.98 ± 0.72 in group C, and 1.14 ± 0.90 in group D, and the differences were statistically significant among the groups(p < 0.01).
DISCUSSION:
OSAHS, particularly the moderate and severe forms, is associated with low Schirmer and TBUT values and high scores in OSDI questionnaire and corneal staining pattern stage. The presence of FES is observed as a practically constant finding in OSAHS. If complaints such as burning, stinging, and itching which can be commonly observed in middle-aged patients are accompanied by FES, the patient should be evaluated for sleep disorders. We speculate that appropriate treatment of OSAHS may result in better control of these symptoms.
Sleep Breath. 2012 Jun 5. [Epub ahead of print]
Acar M, Firat H, Acar U, Ardic S.
Department of Ophthalmology, Ministry of Health, Ankara Diskapi Yildirim Beyazit Training and Research Hospital, Ankara, Turkey, m_acar@hotmail.com.