PC - Binocular Indirect Ophthalmoscopy - Week 2 Flashcards
Describe the following for a BIO: Image of the fundus Image orientation Stereopsis Field of view Magnification Limitation
Image - real Orientation - Reversed and inverted Stereopsis - yes Field of view - 25 degrees Magnification - 2x Limitation - Posterior pole to ora serrata and vitreous
Are cataracts an indication for a BIO exam?
Yes
Name 3 general indications for a BIO exam.
Indications for DFE
1st presentation
Reduced best corrected VA
Name 15 PC indications for a BIO exam.
Reported visual disturbance Photopsia Floaters Metamorphosia Metachromatopsia Shadows Veils Curtain of reduced vision Scotoma VF deficit HA Diplopia Ptosis Pupil abnormalities Trauma (hyphaema)
Name 5 GH indications for a BIO exam.
Diabetes Hypertension Cancer High cholesterol Lupus
Aside from general, PC, GH, and cataracts, name 4 indications for a BIO exam.
Known PVD
Previous RD
Retinal/choroidal lesion
How can a patients entire retina be seen through a BIO?
Need to direct their gaze to see everything.
Which method views better through media opacities, BIO or direct?
BIO
Name 2 advantages of the BIO.
Provides 2x magnification
Large field of view
Compare the magnification of the BIO to a fundus lens.
Lower magnification compared to a fundus lens
Name 3 disadvantages of the BIO.
Image is reverse and inverted
Requires mydriasis
Illumination may be uncomfortable
Are higher power condensing lenses better for smaller or larger pupils?
Smaller
Do higher power condensing lenses provide better or poorer steropsis?
Poorer
Do higher power condensing lenses provide higher or lower magnification?
Lower
Do higher power condensing lenses provide a greater or smaller field of view?
Greater
Must higher power condensing lenses be held closer to or further from the eye?
Closer
Briefly explain the BIO procedure.
Explain the procedure Dilate the pupils Dim the lights Patient at eye level Begin with direct gaze Then direct patient to additional gaze positions
If during BIO the patient looks up from direct gaze, what are you seeing?
Superior retina
How can the vitreous be seen during BIO?
Increase working distance or move the lens in slightly
How would you troubleshoot reduced or no view during BIO?
Tilt the lens
How would you troubleshoot excessive reflections during BIO?
Reduce intensity, tilt lens, change aperture
How would you troubleshoot limited peripheral retinal view during BIO?
Stand opposite to the retinal area examined
Rotate the chair
Tilt or turn the patient’s head
How many disc diameters is the ora serrata from the optic disc?
~10DD
Give a template for a BIO recording
Technique Drops (name, %, dose, eye, time) Mid-periphery NAD (or tick) Periphery NAD (or tick) Vitreous NAD (or tick) If abnormality, then size (DD), shape, colour, raised/flat, location (DD & sector)
Describe scleral indentation, and when it is typically used.
A means of elevating the retina, used when retinal tearing/hole is suspected.
The patient is asked to look up, the indentor is placed between the eye and orbit.
Done with the other gaze directions as well.
