Wavefront sensorless adaptive optics ophthalmoscopy in the human eye

• Published in: Optics express Vol. 19; no. 15; pp. 14160 - 14171
• Main Authors: Hofer, Heidi, Sredar, Nripun, Queener, Hope, Li, Chaohong, Porter, Jason
• Format: Journal Article
• Language: English
• Published: United States Optical Society of America 18.07.2011
• Subjects: Adaptation, Ocular - physiology; Adult; Algorithms; Eye - anatomy & histology; Humans; Image Processing, Computer-Assisted; Ophthalmoscopes; Ophthalmoscopy - methods; Optical Phenomena; Photoreceptor Cells, Vertebrate - cytology; Retina - anatomy & histology
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.19.014160

Wavefront sensor noise and fidelity place a fundamental limit on achievable image quality in current adaptive optics ophthalmoscopes. Additionally, the wavefront sensor 'beacon' can interfere with visual experiments. We demonstrate real-time (25 Hz), wavefront sensorless adaptive optics imaging in the living human eye with image quality rivaling that of wavefront sensor based control in the same system. A stochastic parallel gradient descent algorithm directly optimized the mean intensity in retinal image frames acquired with a confocal adaptive optics scanning laser ophthalmoscope (AOSLO). When imaging through natural, undilated pupils, both control methods resulted in comparable mean image intensities. However, when imaging through dilated pupils, image intensity was generally higher following wavefront sensor-based control. Despite the typically reduced intensity, image contrast was higher, on average, with sensorless control. Wavefront sensorless control is a viable option for imaging the living human eye and future refinements of this technique may result in even greater optical gains.