Quantitative Differentiation of Pneumonia from Normal Lungs: Diagnostic Assessment Using Photoacoustic Spectral Response

Abstract

Pneumonia is an acute lung infection that takes life of many young children in developing countries. Early stage (red hepatization) detection of pneumonia would be pragmatic to control mortality rate. Detection of this disease at early stages demands the knowledge of pathology, making it difficult to screen noninvasively. We propose photoacoustic spectral response (PASR), a noninvasive elasticity-dependent technique for early stage pneumonia detection. We report the quantitative red hepatization detection of pneumonia through median frequency, spectral energy, and variance. Significant contrast in spectral parameters due to change in sample elasticity is found. The tissue-mimicking phantom study illustrates a 39% increase in median frequency for 1.5 times the change in density. On applying to formalin-fixed pneumonia-affected goat lungs, it provides a distinct change in spectral parameters between pneumonia affected areas and normal lungs. The obtained PASR results were found to be highly correlating to standard histopathology. The proposed technique therefore has potential to be a regular diagnostic tool for early pneumonia detection.

Photoacoustic Spectral Sensing Technique for Diagnosis of Biological Tissue Coagulation: In-Vitro Study

“…Moreover, the proposed technique relies on changes in the elastic property of tissue that serves as a potential fingerprint in coagulated tissue study. Our approach has been previously adopted to diagnose different pathological conditions involving minute changes in elastic properties [15,33]. This exhibits the versatility and sensitivity of our PA spectral sensing technique.…”

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

“…Thus the density of follicular cells in the given region increases. Since the frequency spectra reflects the density, the change is reflected in the experimental results [13,21].…”

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.…”