Three common acquisition examples illustrate the breadth of Photoacoustic Image applications:
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Photoacoustic Standalone Image - a study with multiple optical wavelength images acquired over time. No complementary modality images are acquired.
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Photoacoustic/Ultrasound Coupled Acquisition - a study with multiple optical wavelength images and ultrasound images acquired over time.
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Stationary tomographic 3D Photoacoustic/Ultrasound Coupled Acquisition - a study with multiple optical wavelength images and ultrasound images acquired over time where the transducer is mounted on a tomographic frame.
As illustrated in Section AAAAA.3.1, Section AAAAA.3.2 and Section AAAAA.3.3, the acquisition examples focus on the application of the Dimension Index.
The following is a non-comprehensive illustration of an encoding of Photoacoustic data captured without a conventional ultrasound system in either handheld or stationary acquisition mode.
At each of M Temporal Positions, N optical excitation wavelengths are applied in rapid succession and images acquired for each wavelength (in this example, N=2). Although the images at each Temporal Position are separated by some milliseconds, they are nominally at the same temporal position.
A Photoacoustic single wavelength standalone image would be a sub-case of Example 1 (Figure AAAAA.3.1.1-1). In a Photoacoustic Microscopy example, Photoacoustic Image frames are produced by raster-scanning an object at one Temporal Position. One complete acquisition sequence produces a single 2D or 3D image. A repetition of the bespoke scanning sequence in stationary mode capturing a new time point of the same imaged object will increment the Temporal Position Time Offset only.
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Figure AAAAA.3.1.1-1. Example 1 Subcase: Photoacoustic (PA) Single Wavelength Standalone Acquisition
The encoding examples in Section AAAAA.3.1, Section AAAAA.3.2 and Section AAAAA.3.3 follow the same Dimension Index Sequence structures. For brevity, the generic structure is illustrated in this section to be applied in each example. The Dimension Index Sequence for all Photoacoustic files in the examples is described in Table AAAAA.3.1.2-1.
In this encoding of the example shown in Figure AAAAA.3.1-1, the first frame of the image is shown for two optical wavelength images (Table AAAAA.3.1.3-1 and Table AAAAA.3.1.3-2). For brevity, examples of Photoacoustic attributes are provided in Section AAAAA.3.4.
Table AAAAA.3.1.3-1. Photoacoustic Standalone Example, Wavelength 1, Frame 1
Table AAAAA.3.1.3-2. Photoacoustic Standalone Example, Wavelength 2, Frame 1