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A noninvasive, multimodal photoacoustic and optical coherence tomography (PAT/OCT) scanner for three-dimensional in vivo (3D) skin imaging is described. The system employs an integrated, all optical detection scheme for both modalities in backward mode utilizing a shared 2D optical scanner with a field-of-view of ~13 × 13 mm2. The photoacoustic waves were detected using a Fabry Perot polymer film ultrasound sensor placed on the surface of the skin. The sensor is transparent in the spectral range 590-1200 nm. This permits the photoacoustic excitation beam (670-680 nm) and the OCT probe beam (1050 nm) to be transmitted through the sensor head and into the underlying tissue thus providing a backward mode imaging configuration. The respective OCT and PAT axial resolutions were 8 and 20 µm and the lateral resolutions were 18 and 50-100 µm. The system provides greater penetration depth than previous combined PA/OCT devices due to the longer wavelength of the OCT beam (1050 nm rather than 829-870 nm) and by operating in the tomographic rather than the optical resolution mode of photoacoustic imaging. Three-dimensional in vivo images of the vasculature and the surrounding tissue micro-morphology in murine and human skin were acquired. These studies demonstrated the complementary contrast and tissue information provided by each modality for high-resolution 3D imaging of vascular structures to depths of up to 5 mm. Potential applications include characterizing skin conditions such as tumors, vascular lesions, soft tissue damage such as burns and wounds, inflammatory conditions such as dermatitis and other superficial tissue abnormalities.

Intrasurgical spectral-domain optical coherence tomography evaluation is feasible using the tested system and may positively influence surgical decisions and techniques resulting in an improved patient outcome.

Frequency domain optical coherence tomography (FD-OCT), based on an all-reflective high-speed InGaAs spectrometer, operating in the 1050 nm wavelength region for retinal diagnostics, enables high-speed, volumetric imaging of retinal pathologies with greater penetration into choroidal tissue is compared to conventional 800 nm three-dimensional (3-D) ophthalmic FD-OCT systems. Furthermore, the lower scattering at this wavelength significantly improves imaging performance in cataract patients, thereby widening the clinical applicability of ophthalmic OCT. The clinical performance of two spectrometer-based ophthalmic 3-D OCT systems compared in respect to their clinical performance, one operating at 800 nm with 150 nm bandwidth (approximately 3 microm effective axial resolution) and the other at 1050 nm with 70 nm bandwidth (approximately 7 microm effective axial resolution). Results achieved with 3-D OCT at 1050 nm reveal, for the first time, decisive improvements in image quality for patients with retinal pathologies and clinically significant cataract.

AimsTo evaluate the outcome after two types of retinal pigment epithelium (RPE) transplantation techniques. Methods Fourteen consecutive patients with advanced exudative age-related macular degeneration (AMD) were randomly assigned to RPE-choroid sheet transplantation (group 1) or RPE cell-suspension transplantation (group 2). Outcome measures included best corrected distance and near visual acuity (BCVA), complication and recurrence rates, autofluorescence (AF), angiography, and time-domain and spectral-domain optical coherence tomography (TD-and SD-OCT).

Objective imaging of the optic nerve structure has become central to the management of patients with glaucoma. There is an urgent need in diagnosis and staging for reliable objective precursors and markers. Three-dimensional ultrahigh-resolution frequency domain optical coherence tomography (3D UHR OCT) holds particular promise in this respect since it enables volumetric assessment of intraretinal layers including tomographic data for the retinal nerve fiber layer (RNFL) and optic nerve head. The integrated analysis of this information and the resolution advantage has enabled the development of more informative indices of axonal damage in glaucoma compared with measurements of RNFL thickness and cup-to-disc ratio provided by commercial OCT devices. The potential for UHR OCT in enabling the combined analysis of tomographic and volumetric data on retinal structure is explored. A novel parameter was developed; the three-dimensional minimal distance as the optical correlate of true retinal nerve fiber layer thickness around the optic nerve head region. For the purposes of this pilot study, we present data from a normal subject and from two patients with characteristic optic nerve and retinal nerve fiber layer changes secondary to glaucoma.