Design and Development of Eye Mould for Netra Tarpana Therapy

Abstract

Netra Tarpana, a classical Ayurvedic ocular therapy, requires medicated ghee to be maintained within a therapeutic range of 35–40?°C, yet traditional dough dams lack reproducibility and temperature control. To address this limitation, a temperature-controlled silicone mould was developed using a nichrome wire heating element with a diameter of 0.19 mm and a length of 65 cm. Heating was applied at fixed voltages of 6V, 8V, and 9V, with ghee temperatures measured manually using a calibrated thermometer at an ambient room temperature of 28?°C. The initial ghee temperatures were 38?°C (6V), 36.5?°C (8V), and 35.5?°C (9V). Results showed that at 6V, ghee rose gradually to 40?°C over 30 minutes, providing stable heating suitable for long duration therapy at 8V, ghee reached 42?°C in ~11 minutes, balancing heating speed and stability for shorter sessions; and at 9V, ghee overshot to 45?°C within 15 minutes, demonstrating uncontrolled heating without feedback and posing clinical risk. Electrical calculations confirmed a wire resistance of 25.2??, with power dissipation values of 1.43?W (6V), 2.54?W (8V), and 3.21?W (9V). These findings highlight that voltage selection directly influences heating rate and stability, and that silicone-insulated nichrome moulds can reproducibly maintain ghee within therapeutic limits, supporting modernisation of Netra Tarpana therapy.

Introduction

The study focuses on improving Netra Tarpana—an Ayurvedic eye therapy that uses warm medicated ghee to nourish and rejuvenate ocular tissues. Traditional practice faces challenges because ghee solidifies below 35 °C, requiring frequent reheating, which reduces treatment consistency and increases contamination risk. To address this, the researchers designed a temperature-controlled eye mould that integrates biomedical engineering principles.

The mould is made of food-grade silicone for biocompatibility, flexibility, and thermal insulation. A 0.19 mm, 65 cm nichrome wire embedded within the silicone serves as the heating element, arranged to ensure uniform heat distribution. Heating performance was tested at 6V, 8V, and 9V without feedback control to study baseline thermal behaviour.

Results showed that 6V provided slow, stable heating, keeping ghee near 40 °C and suitable for long treatments; 8V heated faster, reaching 42 °C in about 11 minutes, making it useful for shorter sessions; 9V caused rapid temperature rise and overshoot to 45 °C, indicating safety risks without advanced control. These findings confirm that silicone insulation combined with nichrome heating can effectively maintain therapeutic temperatures but require careful voltage selection.

The discussion emphasizes the need for closed-loop control systems—such as PWM circuits and integrated sensors—to ensure safety and precision in future versions. Incorporating real-time temperature feedback will improve clinical reliability and keep the ghee consistently within the therapeutic range of 35–40 °C.

Conclusion

This research presents a novel engineering solution to the limitations of traditional Netra Tarpana therapy. The developed silicone mould, powered by a nichrome heating element, demonstrated that voltage selection directly dictates heating outcomes. The 6V input ($1.43\\, W$) offered the most stable therapeutic heating, while higher voltages required active regulation to prevent overshoot. By validating the use of biocompatible silicone and resistive heating, this work lays the foundation for a reproducible, hygienic, and patient-friendly ocular therapy device. Future work will integrate sensor-based feedback and safety cut-offs to fully modernise this Ayurvedic practice.

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Copyright

Copyright © 2025 Basavaraj Endigeri, Pushpavati Policepatil, Basavaraj Katti, Madhura Benakanalli, Shivaprasad Saradar, Vaishnavi Mathapati. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.