Optical spectroscopic determination of human meniscus composition

Abstract

This study investigates the correlation between the composition of human meniscus and its absorption spectrum in the visible (VIS) and near infrared (NIR) spectral range. Meniscus samples (n ¼ 24) were obtained from nonarthritic knees of human cadavers with no history of joint diseases. Specimens (n ¼ 72) were obtained from three distinct sections of the meniscus, namely; anterior, center, posterior. Absorption spectra were acquired from each specimen in the VIS and NIR spectral range (400-1,100 nm). Following spectroscopic probing, the specimens were subjected to biochemical analyses to determine the matrix composition, that is water, hydroxyproline, and uronic acid contents. Multivariate analytical techniques, including principal component analysis (PCA) and partial least squares (PLS) regression, were then used to investigate the correlation between the matrix composition and it spectral response. Our results indicate that the optical absorption of meniscus matrix is related to its composition, and this relationship is optimal in the NIR spectral range (750-1,100 nm). High correlations (R 2 uronic ¼ 86.9%, R 2 water ¼ 83.8%, R 2 hydroxyproline ¼ 81.7%, p < 0.0001) were obtained between the spectral predicted and measured meniscus composition, thus suggesting that spectral data in the NIR range can be utilized for estimating the matrix composition of human meniscus. In conclusion, optical spectroscopy, particularly in the NIR spectral range, is a potential method for evaluating the composition of human meniscus. This presents a promising technique for rapid and nondestructive evaluation of meniscus integrity in real-time during arthroscopic surgery. ß

Fiber development and matrix production in tissue-engineered menisci using bovine mesenchymal stem cells and fibrochondrocytes

“…50/50 co-culture and MSC mono-culture showed an increase in production of hydroxyproline compared to FCC mono-culture, however this increase was not significant (Figure 6D, p>0.05). Tissue engineered menisci when seeded with MSCs have ~30 % of the GAG (μg)/ww(mg) and 40% hypro(μg)/ww(mg) content of human native menisci, while tissue engineered constructs seeded with FCCs have ~12% and 31% respectively (wet weights presented in Supplemental Figure 2)(58). Seeding constructs with MSCs improved the biochemical content to better resemble native values.…”

Ultrasound Assessment of Human Meniscus

“…Furthermore, due to highly organized layered structure of the meniscus, the quantitative ultrasound parameters related to bulk properties of the tissue may not reflect accurately the integrity of the complex tissue, and thus, more sophisticated techniques for analyzing depth dependent ultrasound scattering are needed. In previous studies, multivariate partial least squares (PLS) regression analysis has been applied for analysis of near infrared spectroscopy and optical coherence tomography data measured from articular cartilage and meniscus (Afara et al 2015;Ala-Myllymäki et al 2016;Puhakka et al 2015).…”

“…PLS regression analysis is commonly used to detect relations between noisy predictor variables and one or more response variables. PLS analysis has also been used to correlate the light backscattering with the composition and mechanical properties of cartilage and menisci (Ala-Myllymäki et al 2016;Puhakka et al 2015). However, the applicability of PLS regression analysis of ultrasound backscattering for the determination of structural and compositional parameters from the meniscus is unknown.…”

Optical spectroscopic characterization of human meniscus biomechanical properties

“…32 In the present study, the potential of light in the visible (VIS) region for assessing human meniscus biomechanical properties was also investigated. 33 The motivation for this is based on existing literature where the potential of light in the VIS spectral region for characterizing articular cartilage was demonstrated. 29,34 Recently, we demonstrated the capacity of NIR spectroscopy to predict the composition of the human meniscus.…”

“…29,34 Recently, we demonstrated the capacity of NIR spectroscopy to predict the composition of the human meniscus. 33 Since the meniscus has similar composition as articular cartilage, 11,12 we hypothesize that there is a relationship between the biomechanical properties of human meniscus and its NIR optical response. The motivation behind this hypothesis is a combination of the structure (composition)function relationship of meniscus and the correlation between the spectral response and the composition of meniscus, established in our recent study.…”