Quantitative analysis of angle-resolved scattering properties of ovarian tissue using optical coherence tomography

Abstract

Angle-resolved optical scattering properties of ovarian tissue, on different optical coherence tomography (OCT) imaging planes, were quantitatively measured by fitting the compounded OCT A-lines into a single scattering model. Higher cross correlation value of angle-resolved scattering coefficients between different OCT imaging planes was found in normal ovaries than was present in malignant ovaries. The mean cross correlation coefficient (MCC) was introduced in this pilot study to characterize and differentiate normal, n=6, and malignant, n=4, ovaries. A specificity of 100 percent and a sensitivity of 100 percent were achieved by setting MCC threshold at 0.6. Collagen properties, within the OCT imaging penetration depth, were also qualitatively studied in terms of their content, structure and directivity. The homogeneous three-dimensional collagen fiber network, observed in the normal ovary, effectively explains the stronger cross correlation of angle-resolved scattering properties on different imaging planes while the heterogeneity, observed in the malignant ovary, suggests a weaker correlation.

Fig. 1

Experimental imaging configuration of angle-resolved OCT measurements at 5 different angles of 18 different imaging planes.

Fig. 2

Top: plots of angle-resolved scattering coefficients on 18 different OCT imaging planes from (a) normal ovarian tissue and (b) malignant ovarian tissue. Bottom: OCT images and picrosirius red histology images of normal ovarian tissue (c and d) and malignant ovarian tissue (e and f).

Fig. 3

(a) Scatter plot of mean cross correlation coefficient (MCC) of each ovary for normal and malignant ovary groups. (b) Statistics of normal ($\text{mean}\pm \mathrm{std}$: $0.78\pm 0.11$, $n=6$) and malignant groups ($\text{mean}\pm \mathrm{std}$: $0.42\pm 0.15$, $n=4$).