Goldmann Tonometry

Stuff to remember

The tonometer head is 3.06mm across
Set up correctly - two bits the tonometer clicks into depending on which eye you're doing!
Focus the eyepieces fool
View of the rings is monocular, duh
Wide, full cobalt blue beam @ the axis that gets best illumination
Lights off
x16 magnification is best so head fills as much of view as possible
If px has big cyl (over 4.00) angle head so cyl axis lines up with red line (need to check what this means) and should give a better reading theoretically
Set pressure reading to expected median value (ie about 15) before starting so only a small amount of knob twiddling is needed on the eye

Talking of ON THE EYE

• If your rings are a bit off (not central, top one bigger) MOVE OFF THE CORNEA, adjust and move back onto it again. Have to move off the cornea!1!
• If your rings are off centre in any way you have to move the slit lamp in the direction of the wrongness and that'll sort it. Eg if bottom ring is bigger and the whole picture is shifted to the right, move towards the bigger ring and to the right. Then it should be central.
• If rings are too thick, too much fluorescein!
• If rings are too thin you ain't pressing hard enough. Careful now.
  

The anaesthetics you could use are

• Proxymetacaine 0.5% minims w/0.25% flu (doesn't sting as much due to pH being less acidic, is more expensive and needs to be kept in fridge)
• Lidocaine 4% w/flu 0.25% (for px allergic to proxymet's NH2 benzoic acid esters & for when longer duration of action required)
  
• Amethocaine 0.5% and 1.0% (aka tetracaine, needs fridge)
  
• Oxybuprocaine 0.4% (should be kept cool but doesn't need fridge)

More to be added here most probably!