Adaptive-optics ultrahigh-resolution optical coherence tomography.
Merging of ultrahigh-resolution optical coherence tomography (UHR OCT) and adaptive optics (AO), resulting in high axial (3 microm) and improved transverse resolution (5-10 microm) is demonstrated for the first time to our knowledge in in vivo retinal imaging. A compact (300 mm x 300 mm) closed-loop AO system, based on a real-time Hartmann-Shack wave-front sensor operating at 30 Hz and a 37-actuator membrane deformable mirror, is interfaced to an UHR OCT system, based on a commercial OCT instrument, employing a compact Ti:sapphire laser with 130-nm bandwidth. Closed-loop correction of both ocular and system aberrations results in a residual uncorrected wave-front rms of 0.1 microm for a 3.68-mm pupil diameter. When this level of correction is achieved, OCT images are obtained under a static mirror configuration. By use of AO, an improvement of the transverse resolution of two to three times, compared with UHR OCT systems used so far, is obtained. A significant signal-to-noise ratio improvement of up to 9 dB in corrected compared with uncorrected OCT tomograms is also achieved.
Hermann
B
B
Department of Medical Physics, Christian Doppler Laboratory, Medical University of Vienna, Austria.
Fernández
E J
EJ
Unterhuber
A
A
Sattmann
H
H
Fercher
A F
AF
Drexler
W
W
Prieto
P M
PM
Artal
P
P
D004867:Equipment Design; D019544:Equipment Failure Analysis; D005246:Feedback; D006801:Humans; D019721:Ophthalmoscopes; D009887:Ophthalmoscopy / Q000379:methods; D012160:Retina / Q000473:pathology*; D041623:Tomography, Optical Coherence / Q000295:instrumentation* / Q000379:methods