Slit Lamp Techniques Flashcards
What is the purpose of sclerotic scatter in biomicroscopy?
To evaluate corneal clarity
Specifically useful for assessing corneal clouding secondary to PMMA lenses.
How is the illumination system positioned for sclerotic scatter?
Approximately 60 degrees from the oculars, illuminating the temporal limbus with a 1 mm wide beam.
What does the optic section technique estimate?
Angle depth and localization of lesions
Example: Van Herick for angle depth and corneal defects for lesions.
What is the beam width used in the optic section technique?
Approximately 0.5 mm wide.
What is the purpose of the conical beam technique?
To assess the anterior chamber for cells and flare.
What settings are recommended for the conical beam?
Beam width and height set as small as possible; examiner should be dark-adapted.
What does specular reflection evaluate?
Corneal endothelium and anterior and posterior lens surfaces.
How wide is the beam used in specular reflection?
Approximately 1 mm wide.
What is the angle adjustment for oculars and beam in specular reflection?
Set at equal angles of incidence and reflection.
What is the purpose of indirect illumination?
To evaluate non-opaque corneal lesions.
What types of lesions can be evaluated using indirect illumination?
Microcysts and fingerprint lesions.
What filter is used in conjunction with sodium fluorescein for better visualization?
Cobalt blue filter.
What does the cobalt blue filter help visualize?
Corneal and tear film integrity.
What happens to corneal iron rings when the cobalt blue filter is used without fluorescein?
They appear black.
What is the clinical significance of detecting Fleischer rings?
Useful in diagnosing keratoconus.
