Photoacoustic detection and optical spectroscopy of high-intensity focused ultrasound-induced thermal lesions in biologic tissue

Abstract

Using a PA approach, HIFU-treated tissues interrogated at 720 and 845 nm optical wavelengths can be differentiated from untreated tissues. Based on the authors' spectroscopic investigation, the authors conclude that the observed PA contrast between HIFU-induced thermal lesions and untreated tissue is due, in part, to the increase in the optical absorption coefficient, the reduced scattering coefficient and, therefore, the deposited laser energy fluence in HIFU-treated tissues.

Thermometry and ablation monitoring with ultrasound

“…The authors attribute the reduced signal to a “reduced concentration of blood, tissue dehydration, denaturation of proteins and porphyrins, and reduction of thermoacoustic efficiency in the thermally treated tissue.” However, other researchers have reported an increased PA signal in images acquired at 720 and 845 nm in HIFU-induced thermal lesions in chicken breast (192). …”

Electromagnetic–Acoustic Sensing for Biomedical Applications

“…), in which heat is used to ablate abnormal tissue such as tumors. During the process of thermotherapy, to ensure only the cancerous cells are destroyed while leaving surrounding healthy tissue unaffected, such thermometry or dosimetry with deep penetration is of particular importance [ 102 , 103 ].…”

Diffuse reflectance spectroscopy for identification of carcinogen transformation stages in skin tissue

“…Various types of optical spectroscopy have been investigated as methods for assessment of tissue pathology [7]. All of these methods have one basic principle in common: the optical spectrum of tissue contains information about the biochemical composition and/or the structure of the tissue, and that information conveys diagnostic information [8].…”