Anterior segment optical coherence tomography provided reliable
assessment of lens density and opacity, according to results of a study.
Christopher K.S. Leung
Anterior segment OCT measurements correlated with Lens Opacities
Classification System III (LOCS III) nuclear opalescence and nuclear color
scores, the study authors said.
“The key advantage of using [anterior segment] OCT for lens
assessment is objectivity,” corresponding author Christopher K.S. Leung,
MD, said in an e-mail interview with Ocular Surgery News.
“Having a wide measurement range and high measurement repeatability,
anterior segment OCT could be used to sensitively detect cataract
Data on anterior segment OCT assessment of lens density and opacity are
scant, the authors said. However, further research may lead to anterior segment
OCT becoming the gold standard for evaluating cataract density in clinical
practice and in epidemiological studies.
Patients and methods
The study included 55 eyes of 55 patients (30 women and 25 men) with a
mean age of 69.9 years. One eye of each patient was randomly selected to
undergo both LOCS III scoring and anterior segment OCT imaging.
For LOCS III grading, each pupil was dilated to a diameter more than 6
mm. One investigator, using a Haag-Streit slit lamp microscope, graded nuclear
opalescence and nuclear color on a scale of 0.1 to 6.9, and cortical opacity
and posterior capsular opacity on a scale of 0.1 to 5.9. Investigators used
only nuclear opalescence and nuclear color scores to gauge correlations with
anterior segment OCT images.
Investigators acquired anterior segment OCT images with the Visante OCT
Model 1000 (Carl Zeiss Meditec). A lone investigator obtained three pairs of
images for each patient.
The study had a few limitations. For example, the area chosen for lens
density measurement included only the nucleus, the authors said.
“The current software of [anterior segment] OCT does not provide
lens density measurement,” Dr. Leung said. “Because the infrared
light cannot penetrate through the iris, lens signal posterior to the iris
would be obscured and dilation is needed to maximize lens exposure.”
Study results showed a mean LOCS III nuclear opalescence score of 3.39
and a mean nuclear color score of 3.37. The authors saw significant
correlations between anterior segment OCT measurements and LOCS III nuclear
opalescence scores and nuclear color scores; both associations were
statistically significant (P < .001). Data showed a slightly stronger
association between the mean LOCS III nuclear opalescence score and anterior
segment OCT nuclear density measurements.
“The slightly higher association with the [nuclear opalescence]
score suggests that [anterior segment] OCT provides a better surrogate on lens
density than lens color,” the authors said.
Also, data showed no significant association between logMAR visual
acuity and mean LOCS III nuclear opalescence/nuclear color scores or mean
anterior segment OCT lens density measurement.
“This result is not surprising, since lens density could be more
related to high spatial frequency contrast and sensitivity,” the authors
said. — by Matt Hasson
- Wong AL, Leung CK, Weinreb RN, et al. Quantitative assessment of
lens opacities with anterior segment optical coherence tomography. Br J
- Christopher K.S. Leung, MD, can be reached at Department of
Ophthalmology & Visual Sciences, Chinese University of Hong Kong, Hong Kong
Eye Hospital, 147K Argyle St., Kowloon, Hong Kong; e-mail:
firstname.lastname@example.org. Dr. Leung has
received speaker honorariums and research support from Carl Zeiss Meditec.