Tear film osmolarity in patients with thyroid ophthalmopathy.
OBJECTIVE
To compare tear film osmolarity between patients with thyroid ophthalmopathy and normal healthy subjects.


METHODS
The tear film osmolarity in 15 normal subjects (15 eyes) (control group) and 21 patients (21 eyes) with thyroid ophthalmopathy was evaluated. Tear film osmolarity in milliosmole (mOsm) was determined by using an auto-osmometer. The palpebral fissure width, degree of proptosis, and tear break-up time (BUT) were also determined. The results for the two groups were compared statistically.


RESULTS
The mean palpebral fissure width was 9.13 +/- 0.74 mm in the healthy subjects and 13.33 +/- 1.55 mm in the thyroid ophthalmopathy patients. This difference was statistically significant (P = 0.0001). The mean proptosis was 15.33 +/- 1.39 Hertel units in the healthy subjects and 20.71 +/- 0.95 Hertel units in the patients. This difference was also statistically significant (P = 0.0001). The mean tear BUT was 6.35 +/- 1.56 s in the patients and 18.27 +/- 1.53 s in the healthy subjects, and this difference was also statistically significant (P = 0.0005). The mean tear film osmolarity was 290.80 +/- 13.58 mOsm in the healthy subjects and 340.38 +/- 18.74 mOsm in the patients. There was a statistically significant difference between the groups (P = 0.0001).


CONCLUSIONS
The significantly higher tear film osmolarity in patients with thyroid ophthalmopathy was most likely due to the increased proptosis and lid fissure width. These conditions may lead to injury of the ocular surface.
Iskeleli
Guzin
G
Cerrahpasa Faculty of Medicine, Department of Ophthalmology, Istanbul University, Istanbul, Turkey. giskeleli@superonline.com.
Karakoc
Yunus
Y
Faculty of Medicine, Department of Physiology, Inonu University, Malatya, Turkey.
Abdula
Arzu
A
Cerrahpasa Faculty of Medicine, Department of Ophthalmology, Istanbul University, Istanbul, Turkey.
D000328:Adult; D015352:Dry Eye Syndromes / Q000209:etiology / Q000378:metabolism; D005094:Exophthalmos / Q000209:etiology; D005260:Female; D049970:Graves Ophthalmopathy / Q000150:complications / Q000378:metabolism*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009994:Osmolar Concentration; D013666:Tears / Q000737:chemistry*
J Ocul Pharmacol Ther. 2003 Jun;19(3):281-9
12828846
CLAO J. 1995 Oct;21(4):221-32
8565190
Invest Ophthalmol Vis Sci. 2004 Dec;45(12):4293-301
15557435
Arch Ophthalmol. 1983 Apr;101(4):557-8
6838413
Clin Exp Rheumatol. 1989 Mar-Apr;7(2):155-7
2736828
N Engl J Med. 1993 Feb 25;328(8):584
8426634
Eye Contact Lens. 2005 Sep;31(5):186-93
16163009
Int J Androl. 2002 Aug;25(4):230-5
12180413
Br J Pharmacol. 1997 Apr;120(7):1312-8
9105707
Am J Ophthalmol. 1989 Apr 15;107(4):348-55
2929705
Klin Oczna. 2005;107(7-9):479-82
16417002
Acta Ophthalmol (Copenh). 1992 Jun;70(3):346-9
1636395
Acta Ophthalmol (Copenh). 1983 Feb;61(1):108-16
6687972
Trans Am Ophthalmol Soc. 2006;104:121-8
17471332
Ophthalmology. 1984 Oct;91(10):1205-12
6514286