keratoconus(锥形角膜)

What is keratoconus?

1. thining of the corneal stroma

2. protrusion of cornea
3. irregular astigmatism
4. progressive disease

Risk factor?
1. pigmented skin/ dark skin
2. those live at high landed
3. 20-30 years old
4. frequent rubbing eye
5. genetic
6. contact lens

Onset?
around puberty

How to detect keratoconus?
This is for early detection.
1.retinoscopy--scissor movement (Scissor movement also will be seen in SPK)
2.ofthalmoscopy--oil droplet reflex
3.frequent changes of glasses

>other methods to detect keratoconus.
4.keratometry--high K-reading(normal k-reading:40-48D),mire cannot superimpose
5.pachymetry--thin cornea(normal corneal thickness=500-550nm)
However, there are variation between different people. Some people may have thin cornea and high K-reading naturally. Some are having low K-reading and thick cornea although they have keratoconus.

only seen in moderate to severe level.
6.slit lamp-- Fleischer's ring

vogt's line,

7.others--Munson's sign

8.corneal topography
Next time i will show you how to analyze the corneal topograph of keratoconus.


Management?
1.soft contact lens--Prefect K
2.RGP--Rose K, Igel K, Soflex


3.intact

4.corneal cross linking
CCL is to strengthen the corneal structure to reduce the progression of keratoconus. The vision after CCL will not improve so much, just 1-2 lines.

5.corneal graft.
Corneal graft always the last option to treat the keratoconus. there are some risks of corneal graft like rejection and may induce glaucome(due to the steroid eyedrop after surgery).