Fig. 19. Cyclocryotherapy. A. Calipers mark a point on the bulbar conjunctiva 4 mm from the limbus. B. A Linde unit 2.3-mm probe straddles the mark made in A. Inset. Probe temperature is lowered to -60°C and maintained in contact with sclera for 30 seconds after a 6-mm iceball forms. C. The 2.3-mm probe creates and maintains a 6-mm iceball at -60°C. A 1-mm clear area is left proximal to the limbus to prevent freezing the cornea. D. A probe is applied to the superior half of the globe so that an area of approximately 200 degrees is treated by overlapping iceballs. |