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Spectral and Angle-Resolved Magneto-Optical Characterization of Photonic Nanostructures
Published on: November 21, 2019
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Spatial effect of conical angle on optical-thermal distribution for circumferential photocoagulation
Van Gia Truong1,2, Suhyun Park3,2, Van Nam Tran1
1Interdisciplinary Program of Marine-Bio, Electrical & Mechanical Engineering, Pukyong National University, Busan, South Korea.
Biomedical Optics Express
|January 4, 2018
Summary
Optimizing laser treatment for tubular tissues requires uniform light delivery. A 25° conical angle for diffuser tips ensures consistent light emission and effective thermal tissue coagulation, improving photothermal therapy outcomes.
Area of Science:
- Biomedical Engineering
- Optical Physics
- Surgical Technology
Background:
- Uniform light distribution is crucial for effective laser treatment of tubular tissues.
- Current laser applicators may lack consistent radial light emission, impacting therapeutic outcomes.
- Optimizing diffuser tip geometry is key to enhancing photothermal therapy precision.
Purpose of the Study:
- To investigate the impact of conical diffuser tip angles on light emission uniformity.
- To quantitatively assess the thermal effects and tissue coagulation achieved with different diffuser angles.
- To identify an optimal conical angle for uniform light distribution in tubular tissue laser treatment.
Main Methods:
- Utilized a customized goniometer to measure spatial light propagation uniformity.
- Developed an ex vivo model to evaluate temperature development in tissues.
- Quantitatively analyzed irreversible tissue coagulation resulting from laser treatment.
Main Results:
- A 10-mm diffuser tip with a 25° conical angle demonstrated highly uniform longitudinal intensity profiles (0.90 ± 0.07).
- Consistent thermal denaturation was observed on the ex vivo tissue samples treated with the 25° diffuser tip.
- The 25° angle significantly improved radial light uniformity compared to other tested angles.
Conclusions:
- The 25° conical angle is optimal for achieving uniform light distribution from laser diffuser tips in tubular tissue applications.
- This optimized angle enhances the consistency and efficacy of photothermal treatments.
- The findings provide critical insights for designing advanced laser applicators for precise tissue ablation.
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