Principles of Laser Therapy

  • Hatem Krema


Since its inception, laser has been increasingly used for treatment of multiple ocular conditions. Stimulated emission of photons in a lasing medium produces laser beams that vary in their energy according to their wavelength. Ophthalmic lasers could produce thermal, chemical, or mechanical effects on ocular tissues. The factors that determine the laser effects include the degree of absorption of a specific laser wavelength by the tissue pigments, laser power, the size of laser spot on the target tissue, the duration of application, and media clarity.

Ophthalmic lasers are delivered through slit lamp, indirect ophthalmoscope, or fiber-optic probe. Advanced delivery systems enabled more tolerable, precise, and shorter treatment sessions that can be monitored on a wide screen.

Techniques of ophthalmic laser therapy include laser photocoagulation, transpupillary thermotherapy, and photodynamic therapy. These techniques are employed in ophthalmic oncology to treat a variety of intraocular and periocular tumors. Laser is used as a primary or adjuvant treatment and as a treatment for some radiation-induced toxicities.


Laser Physics Wavelength Photodynamic Photocoagulation Thermotherapy 


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Hatem Krema
    • 1
  1. 1.Ocular Oncology Service, Princess Margaret Cancer Center/University Health NetworkTorontoCanada

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