1. STUDY MOTIVATION
Glaucomas are eye diseases in which intraocular pressure damages the optic nerve
Glaucoma often has no symptoms other than progressive permanent vision loss
There is no cure, but early diagnosis and treatment can manage the disease progression
Current diagnosis protocols involve specialized tests and careful examination of the eye
Hypothesis
Some glaucomas are caused by vascular deterioration and associated with capillary abnormalities
Very early, non-invasive and simple diagnosis may be made by microscopic examination nailfold capilaries

2. Nailfold Capillary Abnormalities in Exfoliation Syndrome
Clara C. Cousins1
Courtney Bovee2, Angela Turalba2, Lucy Shen2, Stacey Brauner2, Scott Greenstein2, Ai Ren2, Jay Wang2, Janey L. Wiggs2, Paul Knepper3, Jae H. Kang3, Louis R. Pasquale2,4
1Harvard College, 2Massachusetts Eye and Ear Infirmary, Boston MA; 3Northwestern University Feinberg School of Medicine, Chicago IL; 4Brigham & Women’s Hospital, and Harvard Medical School, Boston MA
STUDY PURPOSE
To investigate nailfold capillary morphological abnormalities in exfoliation syndrome and glaucoma (XFS/XFG) compared to primary open-angle glaucoma (POAG) and controls through nailfold videomicroscopy
STUDY POPULATION
80 POAG, 51 XFS/XFG, 67 controls from MEEI age 40-80
Controls: IOP < 22 mmHg OU, CDR ≤ 0.6 OU
POAG diagnosis with visual field loss on reliable perimetry
XFS/XFG exfoliation material on slit lamp exam

3. ASSESSMENT OF NAILFOLD CAPILLARY MORPHOLOGY ABNORMALITIES
Hemorrhage
Avascular Zones
Tortuosity via Rating Score
“low” = 0
“mild” = 1
“moderate” = 2
“severe” = 3
Waviness
Tortuosity via Limb Crossing
Control
XFG
Yellow tracing confirms no crossing points in the control, but 3 crossing points in XFG
Straight vascular segment
Traced path of vessel

4. DISCUSSION AND CONCLUSIONS
STATISTICAL ANALYSES
Multivariable logistic regression analysis on severity of microvascular abnormalities in controls, POAG, and XFS/XFG
† Adjusted for age, sex, race, mean arterial pressure, diabetes, arthritis, use of blood thinner, body mass index, smoking, cancer, family history of glaucoma,
Microvascular features
(% distribution)
Multivariable adjusted† odds ratios (95% CI) for POAG v Controls
Multivariable adjusted† odds ratios (95% CI) for XFS/XFG v Controls
Multivariable adjusted‡ odds ratios (95% CI) for XFS/XFG v POAG
Hemorrhages per 100 capillaries
(44)
1.0 (ref)
>0 and < (25)
3.6 (1.4, 9.1)
0.6 (0.2, 2.3)
0.2 (0.1, 0.8)
≥ (30)
6.0 (2.2, 16)
11 (2.7, 47)
0.6 (0.2, 1.8)
P-trend
0.01
<0.0001
0.72
Avascular zones ≥ 200 μm per 100 capillaries
(47)
>0 and < (15)
6.3 (2.0, 20)
11.8 (2.1, 65)
1.2 (0.3, 5.0)
≥ (38)
10.4 (3.5, 31)
48 (9.6, 241)
2.6 (0.9, 7.7)
<.0001
0.08
Microvascular features
(% distribution)
Multivariable adjusted† odds ratios (95% CI) for POAG v Controls
Multivariable adjusted† odds ratios (95% CI) for XFS/XFG v Controls
Multivariable adjusted‡ odds ratios (95% CI) for XFS/XFG v POAG
Tortuosity score
< (46)
1.0 (ref)
≥1.0 and < (26)
5.1 (2.0, 13)
9.7 (2.1, 45)
1.3 (0.4, 4.2)
≥ (28)
2.7 (1.0, 7.7)
21 (5.3, 82)
3.9 (1.2, 12)
P-trend
0.01
<.0001
0.02
Capillary limb crossing points per 100 μm segment per 20 capillaries
< (34)
≥0.5 and < (31)
4.8 (2.0, 12)
4.6 (0.7, 30)
0.8 (0.2, 3.5)
≥ (35)
6.2 (2.2, 18)
259 (25, 2719)
8.1 (2.0, 34)
Waviness ratio per 20 capillaries
< (38)
≥1.2 and < (43)
14 (5.1, 36)
165 (13, 2086)
1.8 (0.5, 6.9)
≥ (19)
4.6 (1.0, 21)
646 (41, 10242)
20 (3.8, 106)
DISCUSSION AND CONCLUSIONS
XFS/XFG exhibit more severe nailfold capillary tortuosity compared to POAG and controls while POAG exhibits more severe tortuosity compared to controls.
XFS/XFG show more avascular zones compared to controls while XFS/XFG show borderline more avascular zones compared to POAG.
XFS/XFG and POAG both contain more nailfold hemorrhages compared to controls.
Three different measures for tortuosity yield consistent findings
Multivariable model decreases effect of confounding by systemic conditions