Pentacam

Question 1

K1

Answer 1

3mm zone flattest meridian in diopters

Question 2

K2

Answer 2

3mm zone steepest meridian in diopters

Question 3

Km

Answer 3

3mm Mean power in D

Question 4

Rh

Answer 4

3mm zone hotizontal curvature in mm

Question 5

Rv

Answer 5

3mm zone vertical curvature in mm

Question 6

Rm

Answer 6

3mm zone mean curvature in mm

Question 7

Qs

Answer 7

Quality specification - must show OK

Question 8

Astig

Answer 8

3mm zone anterior astigmatism

Question 9

Axis

Answer 9

3mm axis of corneal astigmatism

Question 10

Kmax

Answer 10

Maximal K reading
Location of apex of cone

Question 11

Qval

Answer 11

Corneal shape
6mm zone
Normal between -1 and 0
Positive > 0
Negative < -1

Question 12

Progression index

Answer 12

Change in corenal thickenss of whole cornea
>1.1 suggests ectatic disease

Question 13

Saggital curve map

Answer 13

Vertical symmetric bow tie - with the rule astigmatisms - vertical axis more steep

Horizontal symmetric bow tie - against the rule astigmatism

Question 14

What are red flags for ectasia

Answer 14

All 5mm zone:
Superior and ifnerior thickness difference greater than 30um
Difference in thinnest value between both eyes of more than 30um
Difference between apex thickenss and thinnest location of more than 10um
Posterior elevation map >15um or anteiror elevation > 12um

Question 15

WHat are Kmax features of eatly keratoconus

Answer 15

Kmax 47+
Kmax difference between both eyes is >2D

Question 16

What are features of keratoconus progression

Answer 16

Kmax change 1D+
Topographical astigmatism change 1D+
Cornea thickness change >30um