title: In vivo assessment of liver fibrosis using diffuse reflectance and fluorescence spectroscopy: a proof of concept.
abstract: A novel application of diffuse reflectance and fluorescence spectroscopy in the assessment of liver fibrosis is here reported. To induce different stages of liver fibrosis, a sufficient number of male Wistar rats were differentially exposed to chronic administration with carbon tetrachloride. Then, diffuse reflectance and fluorescence spectra were in vivo measured from the liver surface of each animal by a minimal invasive laparoscopic procedure. The liver fibrosis degree was conventionally determined by means of histological examination using the Mason's Trichrome stain, accompanied by hepatic expression of α-sma, and evaluation of the ALT/AST serum levels. The liver from rats exhibiting higher grades of fibrosis showed a significant increase in diffuse reflectance and fluorescence intensity when compared with control animals. At 365 nm, the diffuse reflectance spectrum exhibited an increase of 4 and 3-fold in mild and advanced fibrotic rats, respectively, when compared to the control group. Similarly, the fluorescence emission at 493 nm was 2-fold higher in fibrotic animals than in controls. By using fluorescence intensity, discrimination algorithms indicated 73% sensitivity and 94% specificity for recognition of hepatic fibrosis, while for diffuse reflectance, these values increased up to 85% and 100%, respectively. Taking into consideration there is a special need for developing new diagnostic approaches focused on detecting different stages of liver fibrosis with minimal invasiveness, these results suggest that diffuse reflectance and fluorescence spectroscopy could be worthy of further exploration in patients with liver disease.
authors.affiliation: Laboratorio de Láseres, SEPI-ESIME, Instituto Politécnico Nacional, Unidad Profesional Adolfo López Mateos Zacatenco, México D.F. 07738, Mexico.
authors.forename: Diego
authors.initials: D
authors.lastname: Fabila
authors.forename: José Manuel
authors.initials: JM
authors.lastname: de la Rosa
authors.forename: Suren
authors.initials: S
authors.lastname: Stolik
authors.forename: Edgard
authors.initials: E
authors.lastname: Moreno
authors.forename: Karina
authors.initials: K
authors.lastname: Suárez-Álvarez
authors.forename: Giuliana
authors.initials: G
authors.lastname: López-Navarrete
authors.forename: Carolina
authors.initials: C
authors.lastname: Guzmán
authors.forename: Jesús
authors.initials: J
authors.lastname: Aguirre-García
authors.forename: Christian
authors.initials: C
authors.lastname: Acevedo-García
authors.forename: David
authors.initials: D
authors.lastname: Kershenobich
authors.forename: Galileo
authors.initials: G
authors.lastname: Escobedo
mesh_terms: D000199:Actins / Q000096:biosynthesis; D000818:Animals; D002251:Carbon Tetrachloride / Q000633:toxicity; D010535:Laparoscopy / Q000379:methods; D008099:Liver / Q000473:pathology*; D008103:Liver Cirrhosis / Q000139:chemically induced / Q000473:pathology*; D008111:Liver Function Tests; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D000199:Actins; D002251:Carbon Tetrachloride; C498862:Acta2 protein, rat