Fluid temperature at the corneal endothelium during phacoemulsification: comparison of an ophthalmic viscosurgical device and balanced salt solution using the finite element method.
OBJECTIVE
The purpose of this study was to estimate and compare the temperatures of two different anterior chamber solutions at the corneal endothelial level during phacoemulsification. An ophthalmic viscosurgical device (OVD) and balanced salt solution (BSS) were compared using the finite element method (FEM).


METHODS
The thermal properties of an OVD (IAL-F) and BSS were studied in an experimental setting. A computer-aided design model of ocular anatomy was created in two dimensions. The phaco needle was considered to be the only source of heat generation. Then, the FEM was used to demonstrate the transient temperature distribution in the two ocular models at 10, 20, 30, 40, 50 and 60 s. In these models, the anterior chamber was filled with IAL-F (IAL-F model) or BSS (BSS model).


RESULTS
The heat generation rate of the phaco needle was 0.0004 cal/s/mm(2). The maximum corneal endothelial temperatures for the two models at 60 s were 52.67 and 41.57 degrees C, respectively. The experimental IAL-F model showed fewer changes in temperature for any given time and location. At larger distances from the heat source, less temperature variation was detected.


CONCLUSIONS
Phacoemulsification is a potential heat-generating procedure performed between the delicate anterior chamber structures. During this procedure, IAL-F protects the endothelium against heat better than BSS.
Reepolmaha
Somporn
S
Department of Ophthalmology, Faculty of Medicine, Srinakharinwirot University, Bangkok, Thailand. sommpornr@swu.ac.th
Limtrakarn
Wiroj
W
Uthaisang-Tanechpongtamb
Wanlaya
W
Dechaumphai
Pramote
P
D000085:Acetates / Q000737:chemistry*; D001831:Body Temperature; D003198:Computer Simulation; D004338:Drug Combinations; D004728:Endothelium, Corneal / Q000378:metabolism*; D020342:Finite Element Analysis; D006358:Hot Temperature; D006801:Humans; D008903:Minerals / Q000737:chemistry*; D009883:Ophthalmic Solutions / Q000737:chemistry*; D018918:Phacoemulsification; D012965:Sodium Chloride / Q000737:chemistry*; D055682:Viscoelastic Substances / Q000737:chemistry*
D000085:Acetates; C030660:BSS solution; D004338:Drug Combinations; D008903:Minerals; D009883:Ophthalmic Solutions; D055682:Viscoelastic Substances; D012965:Sodium Chloride