Fat emulsions as diffusive reference standards for tissue simulating phantoms?

Abstract

Intralipid 20% was recently suggested as a diffusive reference standard for tissue simulating phantoms. In this work, we extend previously obtained results to other fat emulsions, specifically Intralipid 10%, Intralipid 30%, Lipovenoes 10%, Lipovenoes 10% PhosphoLipid Reduced, Lipovenoes 20%, Lipofundin S 10%, and Lipofundin S 20%. Of particular importance for practical applications, our measurements carried out at a wavelength of 751 nm show the following features. First, these products show high stability and small batch-to-batch variations in their diffusive optical properties, similar to Intralipid 20%. Second, the absorption coefficient of Intralipid, Lipovenoes, and Lipofundin S are very similar and their measured values are within the experimental errors; moreover the reduced scattering coefficient of Intralipid 20%, Lipovenoes 20%, and Lipofundin S 20% are similar and their measured values are within 5%. Third, the reduced scattering coefficient of Intralipid 10% and Intralipid 30% can be scaled from that of Intralipid 20% with an error of 9% and 2%, respectively. A similar scaling property is valid for Lipovenoes and Lipofundin S. We have verified that this scaling property depends on the composition of the fat emulsions: If the ingredients exactly scale with the concentration then the reduced scattering coefficient almost exactly scale as well.

Dependence of optical scattering from Intralipid in gelatin-gel based tissue-mimicking phantoms on mixing temperature and time

“…1,3,11,12 When Intralipid is added to the bulk matrix, the resulting scattering coefficient μ s and the reduced scattering coefficient μ 0 s [μ 0 s ¼ μ s ð1 − gÞ] of the phantom have a linear dependency on the Intralipid concentration. 13,14 For example, at 751-nm wavelength, μ 0 s is measured to be around 100, 200, and 300 cm −1 for 10%, 20%, and 30% Intralipid solutions, respectively. 14 In addition, Intralipid has negligible absorption in the visible spectral region, 14,15 and a refractive index close to that of soft tissue.…”

“…13,14 For example, at 751-nm wavelength, μ 0 s is measured to be around 100, 200, and 300 cm −1 for 10%, 20%, and 30% Intralipid solutions, respectively. 14 In addition, Intralipid has negligible absorption in the visible spectral region, 14,15 and a refractive index close to that of soft tissue. 1,16 Further, the optical properties of Intralipid from different production batches or vendors have little variation.…”

“…1,16 Further, the optical properties of Intralipid from different production batches or vendors have little variation. 4,14,15,17 These features, together with its low cost and wide availability, have made Intralipid the chosen diffusive reference standard for many phantom studies. 14,15 As a common practice, Intralipidbased phantoms can be made to simulate the optical properties of different types of tissues by varying the concentrations of the scatterer-Intralipid and the absorber, such as India ink.…”

“…4,14,15,17 These features, together with its low cost and wide availability, have made Intralipid the chosen diffusive reference standard for many phantom studies. 14,15 As a common practice, Intralipidbased phantoms can be made to simulate the optical properties of different types of tissues by varying the concentrations of the scatterer-Intralipid and the absorber, such as India ink. 1,11 Intralipid phantoms exist as either aqueous solutions or hydrogels.…”

Dark-field circular depolarization optical coherence microscopy

“…2(a). The setup consists of 1% Lipofundin solution which mimics the scattering property of the soft biological tissues [23]. The scattering effect of the solution is in Fig.…”