Slit Lamp Flashcards
Name the 5 congenital cataracts.
- Anterior axial embryonic
- Ant and post polar
- Sutural
- Pulverulent
- Currulean
What are the normal opacities you may find when examining the lens that are not cataracts.
- Mittendorf’s Dots: remenants of the hyloid artery. Found on the nasal part of the posterior part of the lens
- Epicapsular stars: remenenant of the tunica vasculosa lentis
What are the 3 types of “Direct Illumination”?
Parallelepiped
Optic Section
Conical Beam
Define direct light illumination in SLx
Direct illumination refers to the focusing of the light beam and microscope in the same specific area.
What are the 6 Illumination Techniques?
Diffuse Direct Indirect or Proximal Retroillumination/Transillumination Specular Reflection Sclerotic Scatter
Which illumination technique is most effective illumination at detecting tissue abnormalities ?
Direct Illumination: Parallelpiped
T/F: The optic section is used to determining the depth and location of a defect, most commonly used for cornea or lens.
True. Optic section is a type of Direct illumination technique.
Which type of direct illumination technique provides a 2-D section of the corneal tissue?
Optic section
What are the Landmarks (5-Zones) seen in an optic section?
Pre Corneal Tear Film Epithelium Bowman’s Membrane Stroma Descemet’s Membrane (Endothelium)
Why does an optic section have the “grainy” appearance to the stroma?
Due to “keratocytes” aka corneal fibroblasts
What is the critical difference b/n an optic section of the cornea vs lens?
The angle of illumination
What is the CORRECT source of illumination in order to perform an accurate Van Herick Angle Estimation?
Optic Section
What is the Van Herick angle grade when the width of the chamber interval is 1/4 of the corneal thickness?
2
(less than 1/4 is grade 1,
1/2- 1/4 is a grade 3,
and 1 or higher:1 is 4)
What are the cells and flare we see in the anterior chamber examination with a conical beam?
flare = proteins in the AC Cells = white blood cells that tell us that there is inflammation
The conical beam is a type of what type of illumination?
Direct Illumination (conical beam, optic section and parallelepiped)
T/F: Floating cells in the AC move UP near the warmer iris and DOWN near the cooler posterior corneal surface.
True
What is the purpose of using the sclerotic scatter illumination technique?
To look for corneal edema (loss of corneal transparency)
Which illumination technique uses total internal reflection of the cornea?
Sclerotic Scatter
What is the purpose of Indirect Illumination?
Indirect illumination produces a “softer” illumination to give better detection and definition, it is the 2nd most common and important technique.
Why do you use the specular reflection illumination technique? In other words, which structures can you study using specular reflection?
For cornea endothelium, anterior and posterior lens capsules.
Which illumination technique uses snelle’s law?
Specular reflection
What are the landmarks of the lens you can see when you are using optic section?
(Anterior to posterior)
Anterior capsule, cortex, adult nucleous, infantile nucleous, fetal nucleous, embryonal nucleous, cortex and then posterior capsule. (embryonic nucleous is at the center)
You are focused on the ant capsule. What must you then do to focus on the post capsule?
Tilt the joystick towards the pt.
You are doing retro-illumination of the lens. If the lens has lenticular opacities (such as cortical cataracts and PSCs), what color will theses opacities be?
The lenticular opacities on retro-illumination of the lens will appear as darkened areas.
