In a ray of hope for millions suffering from retinal disorders in the country, researchers at IIT Madras have developed a groundbreaking method to enhance drug delivery directly to the retina by utilising mild laser heating. The innovative approach promises to significantly improve the efficacy of treatments administered through eye injections.
Published in the peer-reviewed Wiley Heat Transfer journal, the research focuses on overcoming the challenges posed by the gel-like vitreous humour in the eye, which is often replaced by less viscous fluids after retinal laser surgery.
Traditional methods of drug delivery rely on slow natural diffusion, which can take hours or even days for drugs to reach effective levels at the target site.
Prof. Arunn Narasimhan, Department of Mechanical Engineering, IIT Madras, designed an experiment using a glass eye mimic geometrically similar to the human eye, water, and silicone oil for the vitreous liquid and a heater to simulate laser heating.
The researchers injected a dye as a drug mimic at specific points in the vitreous region of the eye, and measured concentrations at different retinal locations with and without heating the vitreous liquid.
Remarkably, while natural diffusion alone took 12 hours to achieve effective concentration, the application of mild heating reduced this time to just 12 minutes.
“While with natural diffusion alone, the drug mimic took 12 hours to achieve effective concentration at the target region of the retina, heating the vitreous liquid reduced it to just 12 minutes,” said Shirinvas Vibuthe, Graduate Student, at IIT Madras.
This research is particularly vital for the estimated 11 million individuals in India affected by retinal disorders. Since the retina is the region of the eye that contains blood vessels and nerves, such treatments must be performed carefully and with precision, the team said.
“Using glass-eye experiments and bioheat simulations to analyse invasive treatments in the human eye, we have shown that mild targeted heating can enhance drug delivery to the retina. The medical community needs to take this further and implement it in treatments of retinal diseases,” Narasimhan said.
