Corneal Hydration Control in Fuchs' Endothelial Corneal Dystrophy.
OBJECTIVE
To assess corneal hydration control across a range of severity of Fuchs' endothelial corneal dystrophy (FECD) by measuring the percent recovery per hour (PRPH) of central corneal thickness after swelling the cornea and to determine its association with corneal morphologic parameters.


METHODS
Twenty-three corneas of 23 phakic FECD patients and 8 corneas of 8 healthy control participants devoid of guttae were graded (modified Krachmer scale). Effective endothelial cell density (ECDe) was determined from the area of guttae and local cell density in confocal microscopy images. Steady-state corneal thickness (CTss) and standardized central corneal backscatter were derived from Scheimpflug images. Corneal swelling was induced by wearing a low-oxygen transmissible contact lens for 2 hours in the morning. De-swelling was measured over 5 hours after lens removal or until corneal thickness returned to CTss. Percent recovery per hour was 100 × (1 - e-k), where k was determined from CT(t) = (de-kt) + CTss, and where d was the initial change from CTss.


RESULTS
After contact lens wear, corneas swelled by 9% (95% CI 9-10). Percent recovery per hour was 49%/h (95% CI 41-57) in controls and 37%/h in advanced FECD (95% CI 29-43, P = 0.028). Low PRPH was associated with disease severity, low ECDe, and increased anterior and posterior corneal backscatter. Anterior backscatter was associated with PRPH in a multivariable model (R2 = 0.44).


CONCLUSIONS
Corneal hydration control is impaired in advanced FECD and is inversely related to anterior corneal backscatter. Anterior corneal backscatter might serve as an indicator of impaired endothelium in FECD.
Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
Katrin
K
Wacker
Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
Jay W
JW
McLaren
Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
Katrina M
KM
Kane
Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
Keith H
KH
Baratz
Department of Ophthalmology, Mayo Clinic, Rochester, Minnesota, United States.
Sanjay V
SV
Patel
Ophthalmology. 2015 Aug;122(8):1645-52
26050543
Surv Ophthalmol. 2000 Mar-Apr;44(5):367-408
10734239
Invest Ophthalmol Vis Sci. 1985 Jun;26(6):849-56
4008195
Am J Ophthalmol. 1988 Sep 15;106(3):270-8
3262306
Optom Vis Sci. 1991 Nov;68(11):831-41
1766643
Arch Ophthalmol. 2012 Apr;130(4):433-9
22491913
Arch Ophthalmol. 2012 Jul;130(7):868-74
22410629
Invest Ophthalmol Vis Sci. 1999 Mar;40(3):603-11
10067963
Surv Ophthalmol. 1993 Sep-Oct;38(2):149-68
8235998
Ophthalmology. 2014 Dec;121(12):2325-33
25156138
Invest Ophthalmol Vis Sci. 1989 Mar;30(3):392-9
2925313
Invest Ophthalmol Vis Sci. 1989 May;30(5):845-52
2785979
Invest Ophthalmol Vis Sci. 2016 Jan 1;57(1):227-35
26803798
Trans Am Ophthalmol Soc. 1998;96:229-39; discussion 239-42
10360291
Ophthalmology. 2013 Apr;120(4):687-94
23369486
Curr Eye Res. 1995 May;14(5):349-55
7648860
Arch Ophthalmol. 1978 Nov;96(11):2036-9
309758
Invest Ophthalmol Vis Sci. 2014 Feb 26;55(2):1184-90
24508788
JAMA Ophthalmol. 2013 May;131(5):611-8
23471204
J Physiol. 1972 Feb;221(1):43-54
5016991
Arch Ophthalmol. 2009 Feb;127(2):153-60
19204232
Cornea. 1988;7(1):2-18
3280235
Invest Ophthalmol Vis Sci. 2015 Sep;56(10):5904-11
26348640
Cornea. 2012 Jan;31(1):26-35
22045388
Cornea. 2016 Jun;35(6):878-83
27055221
Invest Ophthalmol Vis Sci. 1981 Jan;20(1):77-85
6969713
Invest Ophthalmol Vis Sci. 2010 Nov;51(11):5610-6
20539002
Prog Retin Eye Res. 2011 Nov;30(6):471-92
21820076