Multispectral Optoacoustic Tomography (MSOT) of Human Breast Cancer

Abstract

In a pilot study, we introduce fast handheld multispectral optoacoustic tomography (MSOT) of the breast at 28 wavelengths, aiming to identify high-resolution optoacoustic (photoacoustic) patterns of breast cancer and noncancerous breast tissue. We imaged 10 female patients ages 48-81 years with malignant nonspecific breast cancer or invasive lobular carcinoma. Three healthy volunteers ages 31-36 years were also imaged. Fast-MSOT was based on unique single-frame-per-pulse (SFPP) image acquisition employed to improve the accuracy of spectral differentiation over using a small number of wavelengths. Breast tissue was illuminated at the 700-970 nm spectral range over 0.56 seconds total scan time. MSOT data were guided by ultrasonography and X-ray mammography or MRI. The extended spectral range allowed the computation of oxygenated hemoglobin (HBO), deoxygenated hemoglobin (HB), total blood volume (TBV), lipid, and water contributions, allowing first insights into high-resolution breast tissue MSOT cancer patterns. TBV and Hb/HBO images resolved marked differences between cancer and control tissue, manifested as a vessel-rich tumor periphery with highly heterogeneous spatial appearance compared with healthy tissue. We observe significant TBV variations between different tumors and between tumors over healthy tissues. Water and fat lipid layers appear disrupted in cancer versus healthy tissue; however, offer weaker contrast compared with TBV images. In contrast to optical methods, MSOT resolves physiologic cancer features with high resolution and revealed patterns not offered by other radiologic modalities. The new features relate to personalized and precision medicine potential. .

Bedside 3D Visualization of Lymphatic Vessels with a Handheld Multispectral Optoacoustic Tomography Device

“…Our pilot study describes the first results of lymphatic vessel visualization by handheld 3D multispectral optoacoustic tomography. While MSOT has been applied in cancer, vascular and inflammatory imaging [4,7,11,18], its use in other fields is still emerging [19]. In addition, MSOT has been shown to provide investigator-independent, consistent and reproducible functional soft tissue characterization [20].…”

Real-time spectroscopic photoacoustic/ultrasound (PAUS) scanning with simultaneous fluence compensation and motion correction for quantitative molecular imaging

“…In particular, PA spectroscopy has produced functional images in the brain and heart [10,[18][19][20], and molecular images using the unique spectra of nanoengineered contrast agents [16,[20][21][22]. These tools have been extended to clinical breast cancer screening [23][24][25][26], skin lesion diagnosis [27,28], biopsy guidance [29,30], gastrointestinal imaging [31], and tumor metastases and lymph node screening [32].…”

Photoacoustic imaging resolves species-specific differences in haemoglobin concentration and oxygenation

“…The relative concentrations of these respective chromophores can then be calculated by spectroscopic inversion 3 . PAI measures of THb (HbR+HbO2) and SO2 (HbO2/THb) have been widely exploited to characterize tissues in the context of different pathologies, for example in breast cancer [4][5][6] , melanomas 7,8 , prostate cancer [9][10][11] , nodal lesions of the head and neck 12 , vascular diseases [13][14][15] and colitis 16 .…”