cryotherapy in ophthalmology

1. CRYOTHERAPY

2. INTRODUCTION
• Different methods to create chorioretinal
adhesion.
• Adhesion produced by all treatment is
between the retina and pigment epithelium,
but referred to as chorioretinal adhesion.

3. CRYOTHERAPY
• Scholer; Freezing creates inflammation in
the area of application.
• Linde instrument employed CO2 or N2O
as cryogenic agents.
• Works on Joule-Thompson principal.

4. Effects on the tissue
• Cryo causes dissolution of cellular
membrane.Intracellular ice causes
mechanical damage with rupture of
cellular membrane.
• Strength of adhesion between retina and
RPE is proprotional to the intensity of
application.
*Light - Barely perceptible
*Medium - Faintly grey
*Heavy - Opaque lesion

5. Development of adhesion over time
• Gains strength rapidly after second day to
reach maximum on 10-12 days
• Heavy burns-1175mg

6. Uses
• Prophylactic treatment of breaks.
• Localized area of detachment.
• Prophylactic treatment of areas of
abnormal vitreoretinal adhesion.
• Anterior retinal cryopexy.

7. Advantages & Disadvantages
• Can be applied through full thickness
sclera.
• Can be applied through hazy media.
• Can be safetly used over LPCN&Art.
• Has little effect on sclera.
• Break down of BRB.
• Greater intravitreal dispersion of RPE.
• CME is more