Gonioscopy

Question 1

What are the 6 indications for Gonio?

Answer 1

1. Narrow Angles
2. Asymmetrical IOPs
3. SOAG
4. Iris abnormalities
5. Trauma
6. Retinal Conditions

Question 2

What are the contraindications of Gonio?

Answer 2

1. Compromised corneal surface
2. Recent trauma
3. Current infectious Ant Seg condition

Question 3

The ____ angle is most narrow and the ___ angle is deepest

Answer 3

Narrow — Superior

Deepest — Inferior

Question 4

Describe the retinal views seen by each mirror in a 3-mirror Gonio lens?

Answer 4

‘Thumb’/Semi-Circle — Anterior (ora to vitreous base)
Rectangle — Peripheral (equator to ora)
Trapezoid — Equator
Circle — Central 30º of posterior pole

Question 5

To view an angle better (e.g. view over the iris), what adjustment should be made to the mirror?

Answer 5

Move lens toward angle

Question 6

If the angle appears narrow, indentation gonioscopy can help differentiate between ____ and ____. How?

Answer 6

Iris bombe vs Iris Plateau

Iris plateau will show a “double hump sign” on indentation

Question 7

What should always be documented when performing Gonio?

Answer 7

1. Pigmentation of TM
2. Angle characteristics
3. Iris contour
4. Deepest structure

Question 8

What angle structure coincides with each grade?

Answer 8

1 — Schwalbe’s Line
2 — TM
3 — Scleral Spur
4 — CB band

Question 9

Corneal wedge indicates location of what structure?

Answer 9

Schwalbe’s Line

Question 10

What is the proper slit lamp settings for Gonio?

Answer 10

1. Optic Section
2. Perpindicular to angle
3. Full illumination
4. 20-30º angle
5. 16-24x mag

Question 11

T/F: blood vessels in the iris are an abnormal finding

Answer 11

FALSE; normal findings, as long as it does not cross TM

Question 12

T/F: both pseudoexfoliation and PDS can cause Pigmentary GLC

Answer 12

TRUE

Question 13

PDS is most common in what demographic?

Answer 13

Young male myopes

Question 14

What might a RD + elevated IOP be indicative of and therefore requires Gonio?

Answer 14

VEGF in retina —> TRD —> VEGF comes to anterior —> NVA —> GLC

Question 15

What are (3) normal angle characteristics that should not cause concern?

Answer 15

1. Blood in Schlemm’s
2. Iris BVs
3. Iris Processes

Question 16

Even though it is a normal finding, blood in Schlemm’s may also be indicative of what?

Answer 16

Sturge Weber

Question 17

Other than neo, what else does VEGF cause in the eye?

Answer 17

Mac edema

Question 18

4 causes of pigment in angle?

Answer 18

1. PDS
2. PXF
3. Angle Recession
4. UGH (Uveitic Glaucoma Hyphema Syndrome)

Question 19

PAS is indicative of 1 or 2 possible causes: ___ and ____

Answer 19

Angle Closure & Uveitis

Question 20

What muscles affected by Angle Recession?

Answer 20

Longitudinal and circular