Abstract: Systems and methods for relaying electrical signals representing acoustic response of a volume of tissue to light and ultrasound stimulation. In an embodiment, a plurality of ultrasound transducers receive acoustic energy from the volume and generate electrical energy, which is transmitted via an electrical path to a relay system. The ultrasound transducers are operated at a wide band frequency of at least 1 MHz to 5 MHz to receive acoustic energy from the volume of tissue responsive to light stimulation and at a narrower band frequency to receive acoustic energy from the volume of tissue responsive to acoustic stimulation. The relay system relays the electrical signals to an optoacoustic system or an ultrasound instrument for further processing depending on whether the electrical signals resulted from ultrasound or light stimulation. In an embodiment, optoacoustic, ultrasound, or other images are generated from the electrical signals and may be coregistered, overlayed, or displayed.

Abstract: A method is disclosed for generating sinograms by sampling transducers acoustically coupled with a surface of a volume after a pulse of light, each transducer being associated with a channel in an optoacoustic imaging system, and processing at least two multi-channel sinograms, each corresponding to a different one of the at least two different predominant wavelengths, to create at least two processed sinograms. The processing step includes a step of sub-band acoustic compensation. Image reconstruction is performed based upon the processed sinograms to generate at least two optoacoustic images. Image post processing is performed on the optoacoustic images to generate post-processed images. A parametric map is generated based upon information contained in the post-processed images, and an ultrasound image is generated using the transducers. The parametric map and the ultrasound image are co-registered and a co-registered image is displayed.

Abstract: The quality of a parametric map is improved based upon information contained in optoacoustic images. Frames are acquired by a multi-wavelength optoacoustic imaging system. A first sub-set including uncorrelated frames from a first wavelength is generated. A first interframe artifact estimate is generated. The first artifact estimate is applied to a frame from a first wavelength to mitigate the interframe persistent artifact in the frame, creating a first processed frame. A second sub-set including uncorrelated frames from a second wavelength is generated. A second interframe artifact estimate is generated. The second artifact estimate is applied to a frame from the second wavelength to mitigate the artifact in the frame from the second wavelength, creating a second processed frame. A parametric map is generated from information in the first processed frame and information in the second processed frame.

Abstract: Electromagnetic energy is deposited into a volume, an acoustic return signal from energy deposited in the volume is measured, and a parametric map that estimates values of at least one parameter as spatially represented in the volume is computed. A reference level of a region of interest is determined, and upper and lower color map limits are specified, with at least one of them being determined in relation to the reference level. The parametric map is then rendered in the palette of a color map by mapping the estimated values of the parametric map onto the color map according to the color map limits. Two wavelengths of energy can be applied to the volume, and the parametric map computation can be adapted by applying an implicit or explicit model of, or theoretical basis for, distribution of electromagnetic energy fluence within the volume pertaining to the two wavelengths.

Abstract: An optoacoustic imaging system includes a handheld probe and first and second pulsed light sources having a common output. The first and second light sources generate pulses of light at first and second predominant wavelengths, respectively. The handheld probe includes an ultrasound transducer array having an active end located at the distal end of the handheld probe for receiving an optoacoustic return signal. A sensor measures a portion of the light transmitted along the light path. A data acquisition samples the ultrasound transducer array during a predetermined period of time after a pulse of light from the first light source and during a predetermined period of time after a pulse of light from the second light source. The sampled data is stored.

Abstract: A system and method are provided for normalizing range in an optoacoustic imaging system. In an embodiment, the system includes adjustable amplifiers and a probe having an array of transducer elements, each of the adjustable amplifiers being associated with one or more of the transducer elements. The transducer elements are acoustically coupled with a surface of a volume. The gain on the adjustable amplifiers is changed as a function of the passage of time during a predetermined period of time after a pulse of light. A sinogram is recorded by sampling the adjustably amplified plurality of transducer elements for the predetermined period of time. The sinogram is processed by substantially reversing the changing step mathematically, and storing the results in an expanded dynamic range sinogram. The expanded dynamic range sinogram provides sufficient numeric precision to permit the reversal of the changing step without materially decreasing the dynamic range of the information in the sinogram.

Abstract: An optoacoustic imaging system includes a hand-held imaging probe having a light emitting portion and an array of ultrasonic transducers. The probe includes an acoustic lens having an optically reflective material that operates to avoid image artifacts associated with light interactions with the acoustic lens. The optically reflective material may be a thin, highly optically reflective metallic layer. The acoustic lens may be formed from a material such as silicon rubber filled with titanium dioxide or barium sulfate that allows it to reflect and scatter light from illumination components with substantially no absorption of such light, and yet be optically opaque. The probe may include a housing that provides hypo-echoic encapsulation of the probe. An assembly of the array of ultrasonic transducers may include a hypo-echoic material. The probe may include optical windows, each comprising one or more anti-reflection-coated plates with acoustic impedance matching that of tissues to be imaged.

Abstract: Described is system and method for detecting anomalous channels in an optoacoustic imaging system in which transducer elements are acoustically coupled with a portion of the surface of a volume of tissue and a pulse of light is directed onto an area of the surface, the pulse imparting less than a predetermined fluence upon the surface. A sinogram is recorded by sampling transducers acoustically coupled with the surface of the volume for a predetermined period of time after the pulse of light to record data reflecting the optoacoustic response of the volume of tissue to the pulse, the samples for each transducer corresponding to a channel. The sinogram is analyzed for the presence of one or more anomalous channels, and the sinogram samples corresponding with the anomalous channels are modified to reduce the affect of the anomalous channel on an image reconstructed from the sinogram.

Abstract: A method for controlling an optoacoustic imaging system includes the steps of analyzing sinogram data values to identify variations, storing information concerning the variations, generating first and second sinograms, and processing the sinograms to mitigate the effect of the variations. In the analyzing step, sinogram data values are analyzed to identify one or more variations that are related to performance of one or more of the discrete components of the optoacoustic imaging system. The identified variations are then stored. A first sinogram is generated by sampling transducer elements acoustically coupled with a surface of a volume for a predetermined period of time after delivery of a pulse of light having a first wavelength, the first sinogram containing one channel for each of the transducer elements.

Abstract: A method is disclosed for generating sinograms by sampling a plurality of transducers acoustically coupled with the surface of a volume of tissue over a period of time after a light pulse at one wavelength, and after another light pulse at a different wavelength, and for processing those sinograms, reconstructing at least two optoacoustic images from the two sinograms, processing the two optoacoustic images to generate two envelope images and generating a parametric map from information in the two envelope images. In an embodiment, motion and tracking are determined to align the envelope images. In an embodiment, at least a second parametric map is produced from information in the same two envelope images. In an embodiment an ultrasound image is also acquired, and the parametric map is coregistered with and overlayed upon the ultrasound image, and then displayed.

Abstract: A method is disclosed for creating and outputting a masked parametric map that reflects parameters in a first parametric map and second parametric map. First and second parametric maps are generated, and then a masked parametric map that reflects parameters in the first and second parametric maps is generated. The first parametric map may be based upon portions of two optoacoustic images created using differing wavelengths of light. The first parametric map is reflective of areas within the volume of tissue that have a differing response to the longer wavelength light event compared to the shorter one. The second parametric map is reflective of areas within the volume of tissue that have a stronger response to the longer and shorter wavelength light events than the surrounding areas. A masked parametric map is output which is reflective of a combination of information in the first and second parametric maps.

Abstract: A real-time imaging method that provides ultrasonic imaging and optoacoustic imaging coregistered through application of the same hand-held probe to generate and detect ultrasonic and optoacoustic signals. These signals are digitized, processed and used to reconstruct anatomical maps superimposed with maps of two functional parameters of blood hemoglobin index and blood oxygenation index. The blood hemoglobin index represents blood hemoglobin concentration changes in the areas of diagnostic interest relative to the background blood concentration. The blood oxygenation index represents blood oxygenation changes in the areas of diagnostic interest relative to the background level of blood oxygenation. These coregistered maps can be used to noninvasively differentiate malignant tumors from benign lumps and cysts.

Abstract: An optoacoustic imaging system includes a handheld probe and a computing subsystem. The probe includes an ultrasound transducer array, the array being capable of receiving an acoustic return signal. The system further includes a light source capable of generating pulses of light and delivering the pulses to the handheld probe. The computing subsystem generates images from the acoustic return signal, and the subsystem is configured to store raw data frames in a buffer. Upon actuation of a playback mode via the user input device, the computing subsystem is caused to switch from a live mode wherein images from the acoustic return signal are displayed substantially in real time to the playback mode wherein images are generated from the frames stored in the buffer.

Abstract: A real-time imaging system that provides ultrasonic imaging and optoacoustic imaging coregistered through application of the same hand-held probe to generate and detect ultrasonic and optoacoustic signals. These signals are digitized, processed and used to reconstruct anatomical maps superimposed with maps of two functional parameters of blood hemoglobin index and blood oxygenation index. The blood hemoglobin index represents blood hemoglobin concentration changes in the areas of diagnostic interest relative to the background blood concentration. The blood oxygenation index represents blood oxygenation changes in the areas of diagnostic interest relative to the background level of blood oxygenation. These coregistered maps can be used to noninvasively differentiate malignant tumors from benign lumps and cysts.