1. Rosenfeld PJ, Moshfeghi AA, Puliaﬁto CA. Optical coher-
ence tomography ﬁndings after an intravitreal injection of
bevacizumab (avastin) for neovascular age-related macular
degeneration. Ophthalmic Surg Lasers Imaging 2005;36:331–
2. Avery RL, Pieramici DJ, Rabena MD, Castellarin AA, Nasir
MA, Giust MJ. Intravitreal bevacizumab (avastin) for neovas-
cular age-related macular degeneration. Ophthalmology 2006;
3. Rosenfeld PJ, Fung AE, Puliaﬁto CA. Optical coherence
tomography ﬁndings after an intravitreal injection of bevaci-
zumab (avastin) for macular edema from central retinal vein
occlusion. Ophthalmic Surg Lasers Imaging 2005;36:336 –339.
4. Spaide RF, Fisher YL. Intravitreal bevacizumab (avastin)
treatment of proliferative diabetic retinopathy complicated by
vitreous hemorrhage. Retina 2006;26:275–278.
5. Bakri SJ, Donaldson MJ, Link TP. Rapid regression of disc
neovascularization in a patient with proliferative diabetic
retinopathy following adjunctive intravitreal bevacizumab.
Eye. 2006 May 5; [Epub ahead of print].
6. Mason JO III, Albert MA Jr, Vail R. Intravitreal bevacizumab
(avastin) for refractory pseudophakic cystoid macular edema.
Retina 2006;26:356 –357.
7. Shahar J, Avery RL, Heilweil G, et al. Electrophysiologic and
retinal penetration studies following intravitreal injection of
bevacizumab (avastin). Retina 2006;26:262–269.
8. Manzano RP, Peyman GA, Khan P, Kivilcim M. Testing
intravitreal toxicity of bevacizumab (avastin). Retina
Evaluating Central Corneal Thickness
Measurements With Noncontact
Reﬂectometry and Contact
Suzanna Airiani, MD, Stephen L. Trokel, MD,
Shing M. Lee, MSc, and
Richard E. Braunstein, MD
To compare the central corneal thickness
(CCT) measurements obtained with noncontact optical
low-coherence reﬂectometry (OLCR) and ultrasound
Prospective, comparative observational study.
Three sequential ultrasonic measurements and a
set of ﬁve OLCR scans of 52 eyes of 26 healthy subjects
were recorded. Noncontact measurement was repeated
ﬁve minutes after anesthetic drop instillation.
Mean CCT values for noncontact OLCR and
US pachymetry were 544.03 m and 548.66 m,
respectively, with mean SDs of 0.97 m and 4.63 m,
respectively. Noncontact OLCR measured on average
4.64 m less than US pachymetry (95% conﬁdence
interval ؊7.56 to ؊1.72; P ؍ .003). The OLCR
measured 1.68 m less than US pachymetry in the
thinner cornea group (<548.7 m, n ؍ 24) and 7.48
m less in the thicker group (n ؍ 25). This difference
was statistically signiﬁcant (P ؍ .04).
There was agreement between the two
pachymetric measurements. Noncontact OLCR appeared
to measure slightly smaller than US pachymetry. (Am
J Ophthalmol 2006;142:164 –165. © 2006 by Elsevier
Inc. All rights reserved.)
ENTRAL CORNEAL THICKNESS (CCT) DETERMINATION
has become essential in corneal refractive surgery and
glaucoma patient management.
Ultrasound (US) pachym-
etry has been the current standard for CCT measurement.
The purpose of this study is to compare the CCT of normal
human corneas measured with noncontact optical low-
coherence reﬂectometry (OLCR) vs contact US pachym-
etry. We also evaluated the CCT ﬁve minutes after
anesthetic drop instillation to assess its effect on the OLCR
CCT of 52 eyes of 26 patients was measured at our
center. This study was approved by the institutional review
board, and each patient provided informed consent. The
mean age of patients was 38 years Ϯ 9.9 (mean Ϯ SD) with
a male/female ratio of 14:12. Mean manifest refraction
spherical equivalent was Ϫ4.07 diopters Ϯ 2.56 (range
Ϫ10.50 to ϩ0.25 diopters). All patients had unremarkable
ocular history and had not worn contact lenses for at least
24 hours. In the following sequence, OLCR (Pachmeter,
Haag-Streit AG, Koeniz, Switzerland) (Figure 1) immedi-
ately followed by US pachymetry (DGH500 Pachette;
DGH Technology Inc, Exton, Pennsylvania, USA) and a
second set of OLCR measurements ﬁve minutes after US
pachymetry was performed on each study eye. Final CCT
measurements comparing the two pachymetry methods
were available in 49 eyes of 26 patients. Thirty-nine eyes of
20 patients were studied to compare the thickness before
and ﬁve minutes after anesthetic drop instillation by
OLCR pachymetry. All of the measurements were taken
between 10:00 am and 4:00 pm.
The principal operations of the OLCR and US pachymetry
used in this study have been described elsewhere.
Accepted for publication Jan 13, 2006.
From the Department of Ophthalmology, College of Physicians and
Surgeons of Columbia University (S.A., S.L.T., R.E.B.), and Department
of Biostatistics, Mailman School of Public Health (S.M.L.), Columbia
University, New York, New York.
Haag-Streit AG, Koeniz, Switzerland, provided noncontact optical
low-coherence reﬂectometry to the Department of Ophthalmology,
Columbia University, New York, New York.
Presented in part as a poster session at the 2004 ARVO Annual
Meeting, April 25, 2004, Ft Lauderdale, Florida.
Inquiries to Richard E. Braunstein, MD, Edward S. Harkness Eye
Institute, 635 W 165th Street, Box 39, New York, NY 10032; e-mail: