Differentiation of malignant from benign thyroid nodules using photoacoustic spectral response: a preclinical study

Abstract

Thyroid nodule (TN), a discrete palpable swelling of the thyroid gland, is prevalent among 8% of the adult population. The important concern with these nodules is the differentiation between benign and malignant ones. Since conventional diagnostic techniques (e.g., ultrasound) are not accurate in diagnosis, clinical surgeons adopt to excision biopsy, a golden standard, which requires surgery and removal of the gland. We propose to apply Photoacoustic Spectral Response (PASR), a non-invasive and elasticity based diagnostic technique, onto TN for malignancy diagnosis. In this study, time domain photoacoustic signals were acquired through custom built experimental setup inside the surgical theatre and spectral information were obtained through signal processing. PA spectra could distinguish Follicular Variant of Papillary Thyroid Carcinoma (a thyroid cancer) from the other tissues with a high accuracy which an important challenge in conventional diagnostic techniques. Further, other tissue variants were also successfully differentiated through signal decomposition in a quantitative manner.

Photoacoustic Spectral Response using Ultrasound and Interferometric Sensors: A Correlation Study for a High Bandwidth Real-Time Blood Vasculature Monitoring Application in a Chick-Embryo Chorioallantoic Membrane (CAM) Model

“…41 Several clinical studies have been performed by acquiring the spectral information of the PA signal. 23,24 Compared to imaging, PA sensing can be fast, require a smaller number of system components, and provide additional information as it works on the rise and fall times of the PA signal.…”

“…The spectral information, a plot of amplitude versus frequency, provides information on the number of peaks and energy that can be used to accurately diagnose biological samples. [22][23][24] Yet, it is crucial to note that spectral parameters contain valuable mechano-biological information that can be extracted. By harnessing this information, the technique can not only serve as a screening tool but also provide vital insights from a diagnostic perspective [24][25][26] in a costeffective manner.…”

“…[22][23][24] Yet, it is crucial to note that spectral parameters contain valuable mechano-biological information that can be extracted. By harnessing this information, the technique can not only serve as a screening tool but also provide vital insights from a diagnostic perspective [24][25][26] in a costeffective manner. For instance, the relaxation time of the PA time-domain signal is associated with the elasticity of the sample.…”

Development of a cost-effective compact diode-laser-based photoacoustic sensing instrument for breast tissue diagnosis

“…Differentiate Biological Tissues The PASR and its analysis offer a promising sensing method to differentiate samples based on their mechanobiological properties. 23,24 The time-domain PA signal of the different tissue samples was acquired through an ultrasound transducer (OLYMPUS parametric NDT-V303 model, 3.5 MHz center frequency with 8 MHz bandwidth). Time averaging has been implemented to improve the signal-to-noise ratio (SNR) of the acquired signal.…”

Photoacoustic image-guided interventions

“…Applications of PAI in cancers include early detection, identifying the stages and metastasis, treatment planning and evaluation. 6–12 PAI is revealed to be successful in the diagnosis of breast, 13–19 prostate, 20–26 thyroid, 27–31 melanoma, 32–36 and ovarian 37–41 cancers. In stroke, PAI is utilized for imaging and understanding mechanical thrombolysis, 42 vessel segmentation, 43 and other vessel injuries that are caused by stroke in the brain.…”