97th DOG Annual Meeting 1999
IN VIVO TEMPERATURE MEASURING DURING PHACO-EMULSIFICATION
J. M. Heisler, S. Schumacher, H. Wirt, D. von Domarus
Based on our experience of in vitro measurements of temperature in the anterior chamber in 1994 we designed a new spatula with an integrated probe that enabled us to measure temperature continuously during phacoemulsification without any additional surgical expense.
Methods: We measured temperature in the anterior chamber during 75 phacoemulsifications. Depending on indication we used different energy modes (0 to 100%) and pulsemodi ranging from 3 to 10 pulses per second or continuous ultrasonic output. Different viscoelastic substances were used.
Results: The average temperature in the anterior chamber is 29.5ºC. It adapts to the temperature of the irrigation fluid within seconds as soon as irrigation is started. During phacoemulsification each ultrasonic output causes an increase of temperature. In case of continous mode the average rise of temperature is 2ºC. When pulsemode is used the temperature increases by 1.5ºC. It is important to note that one single pulse may increase the temperature by 0.8ºC close to the phacotip.
The rise of temperature correlates with the type of viscosity of the viscoelastic substance used.
Conclusions: The new probe proved to be a practical device to monitor temperature in the anterior chamber during phacoemulsification. Up to now we did not encounter any critical degrees of temperature. In spite of that we should be aware that a functional irrigation unit, the use of pulsemode or permanent ultrasonic output and in particular the type of viscoelastic material used are important parameters influencing the rise of temperature during phacoemulsification. We will proceed in reporting about new results and use of the new probe.
Augenklinik des AK Barmbek, Hamburg