16
proportional to increase of age. Behind lens is vitreous body section, most in 16-18mm,
but people who has high myopia usually larger than this range.
Important notes for A-scan
：
1,placing the A-probe against patient eye lightly, and don’t press it;
2.The direction of acoustic must through axle center of eye, or obvious measure
errors will be made.
The mark on the B-probe represent the direction of sound beam and the upside of
image.B-scan ultrasound mainly do width scanning ,equivalently equatorial diameter, so
when you want to scan peripheral part, you must change the probe direction or patient
gaze direction , to make the lesion area in the center of image.
The method to get high definition B-scan image :
1. Lesion area located in the central zone;
2. Sound beam must perpendicular to detected interface;
3. Adjust the gain , keep enough strength and low decibel to get the best resolution
image.
Algorithm
The calculation of IOL powers be implanted
，
usually using SRK
Ⅱ
for calculation
，
the formula as below:
P=A*L-2.5*L-0.9(K
1
+K
2
)/2
There into
P IOL degree
A IOL constant
L axial length
K
1
Horizontal corneal diopter
K
2
Vertical corneal diopter
Whe
n 19≤L<20 then AL=A+3
20≤L<21 then AL=A+2
21≤L<22 then AL=A+1
22≤L≤24.5 then AL=A
L>24.5 then AL=A-0.5
Summary of Contents for SK-3000A
Page 12: ...11 1 12 Label This label information is stick on main body of Ophthalmic ultrasound ...
Page 28: ...27 4 5 P scan Test Interface 1 Eye Switch left eye and right eye ...
Page 30: ...29 4 6 B scan Test Interface 1 Eye Switch left eye and right eye ...
Page 35: ...34 ...
Page 41: ...40 2 Click Properties 3 Double click Internet protocol version 4 ICP IPv4 ...