Tomey TMS-5, Instruction Manual

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index).
When the IAI value becomes large, sections with
irregular astigmatism increase on the surface of the
cornea.
The IAI is high immediately after cornea transplantation.
● AA (Analyzed Area)
The AA shows the area (range) analyzed by the
device using percentages. The AA becomes smaller
than normal value in the case of a cornea with
irregular astigmatism because large ranges cannot be
analyzed. In addition, the value becomes smaller than
the normal value in the case of an eye after corneal
transplantation, deteriorating keratoconus, and an eye
with external injuries. The value will be lower when the
patient does not open their eye wide.
● EDP (Elevation /Depression Power)
The EDP indicates the average refractive power of
areas with different refractive powers that appear as
an island, peninsula, or valley shape within the pupil
diameter. If the pupil cannot be inspected, the EDP is
calculated from an area of 4-mm diameter centered at
the video-keratoscope axis. This is used to determine
the so-called central island level after an excimer
laser PRK, together with the EDD described below.
The unit is diopter. Eyes with astigmatism, corneal
transplantation, and keratoconus show abnormal EDP
and EDD values .
● EDD (Elevation/Depression Diameter)
The EDD is the diameter of an area that includes
refractive powers 1 diopter larger than the most
frequent refractive powers found in the pupil diameter,
and the unit is millimeters.
When the EDP and EDD are 0, it is assumed that the
inspection was performed before the index was added
to the program. This phenomenon occurs when the
data is imported from TMS-1 or TMS-2. In this case,