Purpose: A newly developed high-penetration Doppler optical coherence angiography (HP-OCA) with a 1-μm probe beam for non-invasive investigation of vascular pathology of exudative macular diseases is introduced. A descriptive case series is presented to discuss the clinical utility of HP-OCA. Methods: Eleven eyes of 10 subjects with exudative macular disease, including 2 eyes with myopic choroidal neovascularization (mCNV), 4 eyes with age-related macular degeneration (AMD) and 5 eyes with polypoidal choroidal vasculopathy (PCV), were investigated. Two Doppler scanning modes (bi-directional and high-sensitive) of HP-OCA were used for the investigation. HP-OCA provides depth resolved and en face angiograms and a ...

Retinal and choroidal vascular imaging is a key to the better understanding and diagnosis of eye diseases. To achieve comprehensive three-dimensional capillary imaging, we used an enhanced vascular imaging technique, so called adaptive optics optical coherence angiography (AO-OCA). AO-OCA enables in vivo high-resolution and high-contrast micro-vascular imaging by detecting Doppler frequency shifts. Using this technique, the retinal and choroidal vasculatures of healthy subjects were imaged. The results show that both intensity and Doppler power images have sufficient contrast to discriminate almost all vasculatures from the static tissue. However, the choriocapillaris, pre-arterioles, and post-venules in the Sattler layer were more contrasted ...

Purpose: To investigate the tissue properties of keratoconic corneas and normal control in vivo by using polarization-sensitive optical coherence tomography (PS-OCT) and evaluate early keratoconus by the area under the receiver-operating curve and Mahalanobis distances analysis. Methods: Thirty one eyes of 20 patients with keratoconus, seven eyes of four patients with keratoconus suspect, and 25 eyes of 25 normal subjects were investigated by PS-OCT and corneal and anterior segment (CAS)-OCT. Average of en face phase retardation of the posterior surface of the cornea, curvature, videokeratographic parameters, regular and irregular astigmatism, pachymetry map, and elevation were measured. The AROC of ...

Purpose:To evaluate the absolute blood flow rate in a single choroidal vessel using Doppler optical coherence tomography (OCT). Methods:Three choroidal vessels were selected in the right eye of three normal subjects, and were measured with Doppler OCT at a 1,020-nm probe wavelength. The pulsatile change of the blood flow was obtained from synchronized measurement of Doppler OCT and plethysmography. Absolute blood flow rates in choroidal vessels were calculated from Doppler OCT volume data. Results:The cyclic change of the blood flow was quantitatively obtained. Absolute blood flow velocities and blood flow rates at peak systole [mean (SD ...

Purpose To investigate a relationship between birefringence and elasticity of porcine sclera ex vivo using polarization-sensitive optical coherence tomography (PS-OCT). Methods Elastic parameters and birefringence of 19 porcine eyes were measured. Four pieces of scleral strips which were parallel to the limbus, with a width of 4 mm, were dissected from the optic nerve head to the temporal side of each porcine eye. Birefringence of the sclera was measured with a prototype PS-OCT. The strain and force were measured with a uniaxial material tester as the sample was stretched with a speed of 1.8 mm/min after preconditioning. A ...

We present a fiber based multifunctional Jones matrix swept source optical coherence tomography (SS-OCT) system for Doppler and polarization imaging. Jones matrix measurement without using active components such as electro-optic modulators is realized by incident polarization multiplexing based on independent delay of two orthogonal polarization states and polarization diversity detection. In addition to polarization sensitivity, this system measures Doppler flow without extra hardware for phase stabilized SS-OCT detection. An eighth-wave plate was measured to demonstrate the polarization detection accuracy. The optic nerve head of a retina was measured in vivo. Detailed vasculature and birefringent structures were investigated simultaneously.

An office based Doppler and polarization sensitive swept-source optical coherence tomography (Doppler-PS-SS-OCT) was developed for diagnosis and evaluation of abnormalities of anterior eye segment in clinic. A healthy eye was measured in vivo by the Doppler PS-OCT. The results showed that the Doppler PS-OCT may have potential to identify blood vessels and discriminate fibrous tissues in abnormalities, such as scarring in bleb, and scleral inflammation.

A polarization sensitive optical coherence tomography based automated algorithm for segmentation of the chorio-scleral interface is presented. The algorithm employs a two-step segmentation approach. At first, local birefringence based segmentation with low precision is performed to roughly distinguish the choroid and sclera. Successively, a depth oriented slope fitting to phase retardation is applied in both the choroid and sclera. The interface is determined as the cross-point of the two phase retardation slope lines. The algorithm shows potential for functional, objective, and volumetric choroid thickness measurement

An automated chorio-scleral interface (CSI) detection algorithm based on polarization sensitive optical coherence tomography (PS-OCT) is presented. This algorithm employs a two-step scheme based on the phase retardation variation detected by PS-OCT. In the first step, a rough CSI segmentation is implemented to distinguish the choroid and sclera by using depth-oriented second derivative of the phase retardation. Second, the CSI is further finely defined as the intersection of lines fitted to the phase retardation in the choroid and sclera. This algorithm challenges the current back-scattering intensity based CSI segmentation approaches that are not fully based on anatomical and morphological evidence ...