Tomey UD-800 - Page 61

3-29 ■
e) What is a good waveform?
[Contact mode]
The instrument recognizes a waveform as a good one if conditions 1) to 3) listed
below are satisfied and captures the measurement data in auto measurement mode.
1） Each of the following waveforms rises above the level cursor/line position.
■ Eye with initial stage cataracts
Waveform on the front of crystal lens / Waveform on the back of crystal lens /
Retina waveform
■ Dense cataract eye
Waveform on the front of crystal lens / Retina waveform
■ Aphakic eye
Retina waveform
■ IOL eye
Waveform on the front of crystal lens / Retina waveform
2） The retina waveform rises vertically. (Ultrasound wave reaches the
retina perpendicularly.)
When the waveform slopes upward, the measurement tends to be long.
3） Within the measurement range
(Fig. 1)
)
Sharp rise
ACD
(anterior
chamber
depth)
Lens
Axial
length
Retina gate cursor
Sclera
Retina
Depression between retina and sclera
(choroid)
Level cursor/line
50%