confocal scanning laser ophthalmoscope simplifies interpretation.
Engineering has launched a new version of the Heidelberg Retinal Tomograph (HRT),
the HRT3. This confocal scanning laser ophthalmoscope offers many features that
improve its clinical utility. Hardware modifications, including a carrying case
for the scan head and the ability to use a laptop computer to run the software,
make the HRT3 truly portable. But probably the greatest achievement is the ability
to apply the new software to existing HRT data, allowing current users to take advantage
of these improvements.
HRT3 features race-specific databases.
The new HRT software uses an automated analysis
for glaucoma damage called the Glaucoma Probability Score (GPS). It's based on a
three-dimensional model of the entire HRT topographical image, including the optic
disc and surrounding peripapillary retinal nerve fiber layer (RNFL). The 3-D modeling
looks at the width, depth and rim slope of the optic disc as well as the RNFL profile.
A neural network-like analysis calculates the probability that a patient's eye has
structural characteristics consistent with glaucoma. The patient's scan is then
classified as normal, borderline, or outside normal limits.
The HRT3 also has improved progression
analysis. It displays the magnitude of the change as a color gradient, providing
quantitative data on how much change has occurred in the significant areas. This
is useful for comparing physical observations of the optic disc.
can also select the entire cluster of change and the device will automatically outline
an area of contiguous damage. You can track the volume, as well as the area of change,
over time. A progression printout provides change probability maps over time as
well as the trend analysis of the area.
Scan head: 12.5" x 14.5"; table: 36" x 23"
$34,990 to $61,990
SOFTWARE FEATURES: Glaucoma
Probability Score, improved progression analysis.
IMAGE RESOLUTION: 384 x 384
pixels over a 15° x 15° field of view.
CAPTURES AN IMAGE: In approximately
three seconds; total time per patient is approximate-ly one to two minutes per eye.
New printouts are available with the HRT3 software
for GPS analysis and progression results. The GPS printout provides the probability
values for damage consistent with glaucoma, along with the resulting classification
for both eyes together. The new standard OU printout also presents the results for
both eyes, but displays the results based on the required contour line. This printout
presents information on the integrity of the neuro-retinal rim and RNFL by comparing
the patient's results with large and ethnic-specific databases.
A new African-American data-base is
available for analysis of that particularly vulnerable population. There's also
a database of Caucasian and Southeast Indian eyes.
New safeguards improve image quality.
Real-time feedback on variables including focusing, camera alignment, illumination
and optic disc centering, are provided before the image is taken.
The new HRT3 and its software developments
offer powerful analyzes and printouts that simplify not only operation, but also
DR. SEMES IS ASSOCIATE
PROFESSOR AND DIRECTOR OF CONTINUING EDUCATION
AT UNIVERSITY OF ALABAMA BIRMINGHAM SCHOOL OF
Optometric Management, Issue: April 2006