Abstract:
:A full-field speckle interferometry method for non-contact and prospectively high speed Photoacoustic Tomography is introduced and evaluated as proof of concept. Thermoelastic pressure induced changes of the objects topography are acquired in a repetitive mode without any physical contact to the object. In order to obtain high acquisition speed, the object surface is illuminated by laser pulses and imaged onto a high speed camera chip. In a repetitive triple pulse mode, surface displacements can be acquired with nanometre sensitivity and an adjustable sampling rate of e.g. 20 MHz with a total acquisition time far below one second using kHz repetition rate lasers. Due to recurring interferometric referencing, the method is insensitive to thermal drift of the object due to previous pulses or other motion. The size of the investigated area and the spatial and temporal resolution of the detection are scalable. In this study, the approach is validated by measuring a silicone phantom and a porcine skin phantom with embedded silicone absorbers. The reconstruction of the absorbers is presented in 2D and 3D. The sensitivity of the measurement with respect to the photoacoustic detection is discussed. Potentially, Photoacoustic Imaging can be brought a step closer towards non-anaesthetized in vivo imaging and new medical applications not allowing acoustic contact, such as neurosurgical monitoring or burnt skin investigation.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Horstmann J,Spahr H,Buj C,Münter M,Brinkmann Rdoi
10.1088/0031-9155/60/10/4045subject
Has Abstractpub_date
2015-05-21 00:00:00pages
4045-58issue
10eissn
0031-9155issn
1361-6560journal_volume
60pub_type
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