title: Multimodal photoacoustic and optical coherence tomography scanner using an all optical detection scheme for 3D morphological skin imaging.
abstract: 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 mm(2). 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.
authors.forename: Edward Z
authors.initials: EZ
authors.lastname: Zhang
authors.forename: Boris
authors.initials: B
authors.lastname: Povazay
authors.forename: Jan
authors.initials: J
authors.lastname: Laufer
authors.forename: Aneesh
authors.initials: A
authors.lastname: Alex
authors.forename: Bernd
authors.initials: B
authors.lastname: Hofer
authors.forename: Barbara
authors.initials: B
authors.lastname: Pedley
authors.forename: Carl
authors.initials: C
authors.lastname: Glittenberg
authors.forename: Bradley
authors.initials: B
authors.lastname: Treeby
authors.forename: Ben
authors.initials: B
authors.lastname: Cox
authors.forename: Paul
authors.initials: P
authors.lastname: Beard
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Drexler