Basics Of Biomicroscopes Flashcards
Zeus slit lamp
Lamp at base
Haag-Streit
Lamp from top
Greenough type slit lamp
Switch, 2 levels of magnification
Galilean type slit lamp
Knob with multi levels (more than two) levels of magnification
Direct illumination
Both oculars and light beam are focused at the identical location
Diffuse direct illumination
Maximum beam width and height directed between 30-45 degrees. Low magnification, high illumination with 10% grey filter for patient comfort
Direct focal illumination
Max beam height, width varies but mainly narrow. Illumination angle 45-60 degrees, magnification 6x - 40x
Observing detail of specific part of eye
Parrallelepiped
Light beam between diffuse and optic section
Direct focal illumination
Optic section illumination or conical beam, high illumination. Angled at 45-60 degrees or more
Allows for visual dissection of transparent tissue
Conical beam
As short as is wide, used to asses anterior chamber
Tyndall phenomenon
Illumination of “dust particles”
Indirect illumination
Observation and illumination are not focused at the same point
Retro-illumination
“Backlighting” formed by reflecting light of slit beam from a structure more posterior than structure being observed
Direct retro illumination
Observed feature is viewed in direct pathway of reflected light
Infiltrations, small scars, corneal vessels, etc.
Indirect retro illumination
Illumination angle is greatly reduced or increased (viewed against dark background)
Infiltration, small scars, corneal vessels, microcysts, vacuoles
