2. Web sites of interest:
Welch Alleyn
www.panoptic.welchallyn.com
http://www.welchallyn.com/medical/ go to
“optometry student” menu drop down
Red Atlas
http://www.redatlas.com
29. Macula
Lies about 2DD (disc diameters)
temporal to the optic disc
Should be avascular
May appear darker red than
surrounding retina
Should see bright foveal reflex on
younger pts
35. Aerial (real) image
formed between
examiner and
condenser
Aerial image becomes the
object for the binocular
indirect ophthalmoscope
Light reflecting
from retina
gathered by
condenser
36. BIO Condenser
Page 14.1
BIO condensing
lenses are biconvex,
aspheric designs with
one surface more
curved than the other
Less curved
surface toward
patient’s eye
37. Steeper mirror; smaller
reflected images
BIO Condensers
With the less curved
condenser surface
facing the
patient, spherical
aberration is reduced
and the size of the
(interfering) reflected
image of the source is
smaller
Page 14.1
38. Note the “Reflexes” from the Condenser
Retinoschisis
http://www.mrcophth.com/retinacases/retinoschisis2.jpg
40. Using the BIO
From Nova SO
Start out with the condenser close
to the patient’s eye
Keeping it normal to the patient’s
eye, slowly move the condenser
away from the patient
Initially, bright white reflexes are
seen
As the condenser is moved further
out to the correct distance, the
reflexes soften and the aerial image
Optimizing viewing
fills the condenser
distance
41. Initially, bright white
reflexes are seen
As the condenser is moved
further out to the correct
distance, the reflexes soften
and the aerial image fills the
condenser
51. BIO Summary
Page 14.1
The BIO Condenser:
illuminates the patient’s retina
forms an aerial (real, inverted) image of the patient’s fundus
makes both practitioner’s pupils conjugate to patient’s pupil
Choosing a higher power condenser:
requires a shorter object and image distance
increases the illuminated region of the patient’s retina
decreases BIO magnification (mainly due to closer object distance)
increases BIO field of view (mainly due to closer object distance)