Grading Method of Miyata et al for Superficial Punctate Keratopathy (SPK)

 

Superficial punctate keratopathy (SPK) can be seen in patients with the dry eye syndrome.

 

Procedure: fluorescein staining of the cornea measured by an anterior fluorophotometer

 

Parameters:

(1) area of cornea showing fluorescein staining (A)

(2) density of the fluorescein staining (D)

Parameter	Finding	Score
area of punctate staining	none	A0
	less than one third of the cornea	A1
	one to two thirds of the cornea	A2
	more than two thirds of the cornea	A3
density of punctate staining	none	D0
	sparse	D1
	moderate	D2
	high, with overlapping	D3

 

Designations:

(1) A0D0 if no punctate staining is seen

(2) 9 combinations of A1 to A3 and D1 to D3

 

The higher the A and D scores the more severe the SPK.

 

The fluorescein concentration rises exponentially. If the A and D scores are added:

 

X =

= (A score) + (D score)

 

fluorescein concentration in ng/mL =

= 61.2*EXP(0.56*X)