Several exciting papers got published in the last few months. Details are below.

1.Altaf Hussain and co-authors reported a method to noninvasively measure the local optical fluence in optically inhomogeneous scattering media. Further, they combined this method with photoacoustic imaging for compensating the photoacoustic signals for fluence variations in optically inhomogeneous media. Since local optical fluence in biological tissue is of fundamental importance for biomedical optical techniques to achieve quantification, this work is of great importance. The authors describe their approach in : Mapping optical fluence variations in highly scattering media by measuring ultrasonically modulated backscattered light. Altaf Hussain, Khalid Daoudi, Erwin Hondebrink, and Wiendelt Steenbergen. Journal of Biomedical Optics (2014) Vol 19(6), 066002

2.Yolanda Villanueva and co-authors reported a method that uses an integrating sphere as a platform for photoacoustic measurement of the Grüneisen parameter (г) of absorbing liquids. They also derived a simple equation for determining г without the knowledge about detector sensitivity. Validation of the equation is done by determining г of ethanol at room temperature. This exciting method is described in: Photoacoustic measurement of the Grüneisen parameter using an integrating sphere. Yolanda Villanueva, Erwin Hondebrink, Wilma Petersen, and Wiendelt Steenbergen. Review of Scientific Instruments (2014) 85, 074904

3.Peter van Es and co-authors presented photoacoustic computed tomography (PACT) investigation on a healthy human finger, to image blood vessels with a focus on vascularity across the interphalangeal joints. These are the first reported in vivo PACT images showing the vascularization of the human index finger with such richness of detail. The results obtained indicated that the PA cross-sectional images might be used to detect vascular abnormalities such as those arising from angiogenesis associated with inflammatory rheumatic disease. The authors describe their system and results in: Initial results of finger imaging using photoacoustic computed tomography. Peter van Es, Samir K. Biswas, Hein J. Bernelot Moens, Wiendelt Steenbergen, and Srirang Manohar. Journal of Biomedical Optics (2014) Vol 19(6), 060501

4.Khalid Daoudi, Pim van den Berg, and co-authors presented and evaluated a compact and ergonomically designed handheld probe, connected to a portable ultrasound system for inexpensive, real-time dual modality ultrasound/photoacoustic imaging. This novel system is affordable, portable and thus undeniably a step towards clinically acceptable US/PA system. This work envisages a potential in visualizing rheumatoid arthritis using a point of care device. The authors describe their system and results in: Handheld probe integrating laser diode and ultrasound transducer array for ultrasound/photoacoustic dual modality imaging. K. Daoudi, P.J. van den Berg, O. Rabot, A. Kohl, S. Tisserand, P. Brands, and W. Steenbergen. Optics Express (2014) Vol 22 No. 21, 26365-26374