Pinpoint Illumination (Conical / Tyndall's)

Question 1

Describe Pinpoint / conical Illumination:

Answer 1

It is a direct focal, tangential illumination with the slit beam adjusted to a pinpoint of light, permits detection and quantification of aqueous cells and flare.

Question 2

What do you see if no Cells and flare are present?

Answer 2

The anterior chamber is normally optically empty;

That is, the beam of light, even in its most selective form, is not visable as it traverses the normal aqueous humor.

Question 3

What do you see if Cells and flare ARE present?

Answer 3

In the presence of inflammation or abnormal protein, however, abnormal particles (immune cells) floating the the aqueous may reflect light. Like dust in a sunbeam.

Question 4

How are cells and flare graded?

Answer 4

On a scale of 1+ to 4+

Question 5

What causes Cells and flare?

Answer 5

Inflammation

Usually anterior uveitis, iritis and iridocyclitis. Usually trauma related.

Question 6

How is the beam adjusted for Pinpoint/ conical illumination?

Answer 6

The smallest circular beam

Question 7

How is the beam aimed?

Answer 7

Projected through the anterior chamber at a 60-90 deg angle.

Question 8

Answer 8

.

Question 9

Answer 9

.

Question 10

Talking points on Conical beam.

Answer 10

the most sensitive method for observing aqueous flare

If no inflammation is present the aqueous humor will be “optically empty”