Research Focus

Optical and thermal interactions of laser light with tissue, medical applications of lasers.

Research Interests

Dr. Welch is involved in the general field of Medical Optics. His speciality is the optical and thermal response of tissue to laser radiation. Basic science investigations of light and heat propagation in tissue form the bases for evaluating present and future therapeutic and diagnostic applications of lasers.Dr. Welch's projects include the following:   

  • The development of a non-invasive method for imaging blood vessels to create a technology for customizing the treatment of Port Wine Stain. The location, depth and blood flow of enlarged blood vessels associated with Port Wine Stain will be imaged using Optical Coherence Tomography (OCT). This information will be placed in an optical-thermal model to obtain laser dosimetry for treatment of the enlarged vessels.
  • Dr. Welch's group has discovered that the application of hyperosmotic agents to tissue reduces light scattering. This will enhance both light board diagnostic and therapeutic procedures.
  • Working with the FEL facility at Stanford, Dr. Welch is investigating short pulse ablation.

Selected Publications

  •  Rylander, C.G., Digant P. Dave, Taner Akkin, Thomas E. Milner, Kenneth R. Diller, and A. J. Welch, "Quantitative phase-contrast imaging of cells with phase-sensitive optical coherence microscopy," Optics Letters: 29(13), 1509-1511, July 1, 2004.
  •  Simanovskii, D. M., H. a. Schwettman, H. Lee, A. J. Welch, "Midinfrared Optical Breakdown in Transparent Dielectrics," Physical Review Letters: 91(10), September 5, 2003.
  •  Lee, H., R. Tres Ryan, Joel M. H. Teichman, Jeehyun Kim, Bernard Choi, Navanit V. Arakeri, A. J. Welch, "Stone Retropulsion During Holmium: YAG Lithotripsy," J. of Urology: 169, 881-885, March 2003.
  •  Lee, H., Robert T. Ryan, Joel M. H. Teichman, Jaime Landman, Ralph V. Clayman, M.D., Thomas E. Milner, A. J. Welch, "Effect of Lithotripsy on Holmium: YAG Optical Beam Profile," J. of Endourology: 17(2), 63-67, March 2003.