3.1.3

Question 1

What are the advantages of slit lamp over direct

Answer 1

More magnification- replaces plus lens mag with a microscope
Brighter, more flexible beam- “start focus projector” Illumination system
More ways of directing the beam- “the common pivot” + lots of options
Stereoscopic depth perception- binocular pieces (3D)
Patient held steady, observer comfortable- patient seated with head and chin rest
Fine/ steady controls- joystick controls
Better px/ clinician wd- microscopie gives greater working distance
Bigger FoV- as with an ophthalmoscope it looks like your looking through a keyhole

Question 2

What are the advantages of direct over slit lamp

Answer 2

Slit lamp has a brighter slit so less comfortable for patient and causes more glare + scatter
Doesn’t have a thin slit with a large amount of brightness so can see more at once
Has a larger depth of focus as resolution of slit lamp is higher
U can get higher magnifications on slit lamp so direct provides larger field of view
Suitable for all patients eg those in a wheelchair/ kids
Erect image of fundus
Portable