Integrated Photoacoustic Ophthalmoscopy and Spectral-domain Optical Coherence Tomography

The overall goal of this procedure is to demonstrate the integration of Photoacoustic Ophthalmoscopy with spectral domain optical coherence tomography for simultaneous in vivo imaging of the retina in small animals. This is accomplished by first preparing an anesthetized animal by dilating the pupil and paralyzing the iris sphincter muscle. Then real-time S-D-O-C-T cross-section imaging is used to locate the retinal region of interest and to optimize the optical parameters.

A needle ultrasonic transducer placed in contact with the animal's eyelid detects the laser induced photoacoustic signals, and optimizes the position of the ultrasonic transducer for maximal signal amplitude. The final steps are to set the scanning parameters and acquire S-D-O-C-T and PAOM images simultaneously. Ultimately, the optical absorption contrast and optical scattering contrast from the collected images can reveal minute functional variations in the retinal circulation and pigment epithelium together with detailed retinal anatomy.