Quantitative photoacoustic tomography by stochastic search: direct recovery of the optical absorption field.

We present, perhaps for the first time, a stochastic search algorithm in quantitative photoacoustic tomography (QPAT) for a one-step recovery of the optical absorption map from time-resolved photoacoustic signals. Such a direct recovery is free of the numerical inaccuracies inherent in conventional two-step approaches that depend on an accurate estimation of the absorbed energy distribution. The absorption profile parameterized as a vector stochastic process is additively updated over time recursions so as to drive the measurement-prediction misfit to a zero-mean white noise.

Cost-utility of exercise therapy in patients with hip osteoarthritis in primary care.

Objective: To determine the cost-effectiveness (CE) of exercise therapy (intervention group) compared to 'general practitioner (GP) care' (control group) in patients with hip osteoarthritis (OA) in primary care.

Method: This cost-utility analysis was conducted with 120 GPs in the Netherlands from the societal and healthcare perspective. Data on direct medical costs, productivity costs and quality of life (QoL) was collected using standardised questionnaires which were sent to the patients at baseline and at 6, 13, 26, 39 and 52 weeks follow-up.

Effectiveness of exercise therapy added to general practitioner care in patients with hip osteoarthritis: a pragmatic randomized controlled trial.

Objective: To assess the effectiveness of exercise therapy added to general practitioner (GP) care compared with GP care alone, in patients with hip osteoarthritis (OA) during 12 months follow-up.

Methods: We performed a multi-center parallel pragmatic randomized controlled trial in 120 general practices in the Netherlands. 203 patients, aged ≥45 years, with a new episode of hip complaints, complying with the ACR criteria for hip OA were randomized to the intervention group (n = 101; GP care with additional exercise therapy) or the control group (n = 102; GP care only).

A Method for Delineation of Bone Surfaces in Photoacoustic Computed Tomography of the Finger.

Photoacoustic (PA) imaging of interphalangeal peripheral joints is of interest in the context of using the synovial membrane as a surrogate marker of rheumatoid arthritis. Previous work has shown that ultrasound (US) produced by absorption of light at the epidermis reflects on the bone surfaces within the finger. When the reflected signals are backprojected in the region of interest, artifacts are produced, confounding interpretation of the images.

Initial results of finger imaging using photoacoustic computed tomography.

We present a photoacoustic computed tomography investigation on a healthy human finger, to image blood vessels with a focus on vascularity across the interphalangeal joints. The cross-sectional images were acquired using an imager specifically developed for this purpose. The images show rich detail of the digital blood vessels with diameters between 100 μm and 1.