Optos P200T E Series, User Manual, Page: 25 / 72

Chapter 2 - Introduction
opto map plus
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opto map plus is a higher resolution option which is available for opto map color reflectance and
opto map af modalities.
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opto map fa and opto map icg are captured at the opto map plus resolution.
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opto map plus is captured at resolution x1.5 that of the standard resolution opto map.
2.6.3.2 OCT imaging modalities
CAUTION
OCT scans are described using external angles which can be converted to the nominal
'mm' using the scale factor derived from the wide-angle schematic eye model published
by
Navarro et al
1.
. The nominal scale factor is 3.47 degrees/mm for posterior region.
Optos OCT line scan
The scanner moves back and forth along the line of a selected location on the retina (fundus) and generates a
cross-sectional OCT image. The line scan is 48 degrees (14 mm) in length.
The Optos OCT line scan mode lets you capture cross sectional B-Scan OCT images of the vitreo-retina,
retina and choroid-retina structures.
This scan is also known as a B-scan OCT.
FIGURE 3: Optos OCT line scan example position and scan pattern
Optos OCT raster scan
Captures a raster scan of OCT images covering a 48 x 30 degrees (14 mm x 9 mm) central field of view. The
Optos OCT
raster scan comprises 121 horizontal line scans.
The Optos OCT raster scan moves automatically through the scan volume and lets you capture the macula
and optic nerve head within a single OCT volume scan.
FIGURE 4: Optos OCT raster scan example area, scan pattern and fixed center
1. Isabel Escudero-Sanz and Rafael Navarro, "Off-axis aberrations of a wide-angle schematic eye model," J. Opt. Soc. Am. A 16, 1881-1891 (1999).
Part Number: G110230/1ENG Page 25 of 72
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