Instrumentation considerations in spectral imaging for tissue demarcation: comparing three methods of spectral resolution

Abstract

Multiple methodologies exist to implement spectral imaging for tissue demarcation and disease diagnosis. In this paper, benchtop acousto-optic tunable filter (AOTF), liquid-crystal tunable filter (LCTF) and Fourier interferometric spectral imaging systems were quantitatively compared in terms of imaging speed of soft tissue autofluorescence. Optical throughput, image signal-to-noise ratio (SNR), and collagen autofluorescence imaging in chicken breast were assessed. Within this comparison, the Fourier system possessed the largest optical throughput (~50%) relative to the tunable-filter imaging systems; however, its throughput advantage failed to correlate to improved image SNR over the LCTF system. Further, while the autofluorescence imaging capability of the Fourier system exceeded that of the LCTF system for comparable total image integration times, the LCTF is capable of producing equivalent autofluorescence SNR with superior SNR when interrogations at only a few wavelengths are required and the random access filter tuning of the LCTF can be exploited. Therefore, the simple, rugged design and random-access filter-tuning capability of LCTF-based spectral imaging makes it best-suited for clinical development of soft tissue autofluorescence imaging.

A Portable System for On-Site Medical Spectral Imaging: Pre-Clinical Development and Early Evaluation

“…Recently, LCTF-based systems have received attention in various medical application [14,15,16]. Rapid nonmechanical filter adjustment makes LCTF best suited technology for clinical development, optical imaging and characterization of biological composition tissues [17,18,2].…”

“…In surgical procedures concerning tumors, the physician aims to remove the tumor mass with a sufficient margin of normal tissue. Even under the high magnification, however, it is challenging to differentiate regions between the tumor and the healthy tissue, resulting in incomplete removal of the disease or in excision of negative margins [1,2].…”

Spectral Video in Image-Guided Microsurgical Applications: Integrating Imaging Technology into the Clinical Environment and Ergonomic Considerations

“…Real-time contrast enhancement, in particular, allows to reveal probable regions and thus, increases the probability of the complete tumor removal [4,5]. Spectral imaging (SI) and specifically non-ionizing real-time contrast enhancement is promising tool to guide the surgery and increase a likelihood of complete tumor removal [6,7].…”

Effect due to down-tapering on the hybrid mode power confinement in liquid crystal optical fiber

“…Exploiting the special characteristic features of these in sensing applications can be mentioned as another motivation both in frequency and time domains [1][2][3]. Radial and azimuthal orientations in liquid crystal complex molecular structures would alter some critical parameters like refractive index (RI), permittivity, conductivity and many others, and also, the ambient environment would reshuffle the liquid crystal molecular orientation [4][5][6][7].…”