Abstract
Purpose :
To quantitatively describe the temperature in the anterior and posterior chamber necessary for silicone intraocular lens (IOL) condensation to occur in a porcine eye undergoing air-fluid exchange, and to manipulate these conditions to delay IOL condensation.
Methods :
A porcine eye underwent vitrectomy and total lensectomy with anterior chamber implantation of a silicone IOL. Next, an air-fluid exchange with a 3-port 25-gauge pars plana vitrectomy was performed (Stellaris, Bausch & Lomb, St Louis, MO). A 23 gauge K-type thermoprobe was inserted through the pars plana to monitor intraocular temperature immediately posterior to the IOL plane. The porcine eye was suspended in a water bath to achieve 37°C intraocular temperature and the time to complete condensation (TTCC) was recorded. To manipulate intraocular temperature, dry ice was placed over the infusion line, and drops of room temperature balanced saline solution (rt-BSS) and iced balanced saline solution (i-BSS) were delivered over the porcine cornea. Temperature changes by the different techniques were measured and compared, and presence of IOL condensation was visually assessed.
Results :
Ambient room temperature was 23.7°C. Prior to application of dry ice on the infusion line or BSS to the cornea, the posterior chamber temperature was warmed to 37°C. When the intraocular temperature was increased to 37°C, rt-BSS was applied to the cornea and decreased intraocular temperature to 34°C for a mean of 2 minutes. i-BSS decreased the intraocular temperature to 27.8°C for a mean of 1 minute. Infusion line cooling alone caused no appreciable temperature change. When combining infusion line cooling and i-BSS, the temperature fell to 23°C and was sustained for up 4 minutes after a single application of i-BSS. IOL condensation was subjectively visually improved with the dry ice cooled infusion and iced BSS used in combination (but not with i-BSS or dry ice cooled infusion alone).
Conclusions :
Combined anterior segment cooling and icing the infusion line was an effective and inexpensive technique for prolonging induced intraocular temperature changes. With strict temperature control, the time until condensation can be potentiated.
This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.