BIO-HEAT TRANSFER SIMULATION OF SQUARE AND CIRCULAR ARRAY OF RETINAL LASER IRRADIATION

Pan Retinal photocoagulation (PRP), a retinal laser surgical process, is simulated using a three-dimensional bio-heat transfer numerical model. Spots of two different type of array, square array of 3 × 3 spots and a circular array of six spots surrounding a central spot, are sequentially irradiated. Pennes bio-heat transfer model is used as the governing equation. Finite volume method is applied to find the temperature distribution due to laser irradiation inside the human eye. Each spot is heated for 100ms and subsequently cooled for 100ms with an initial laser power of 0.2W. Based on the outcome of temperature distribution, the laser is pulsated in subsequent simulations to reduce the average peak temperature of spots to minimize the temperature induced cell damage. A method to reduce the laser power to attain the peak temperature towards photocoagulation temperature (60 ◦C) is also presented