title: Optical spectroscopy of the bladder washout fluid to optimize fluorescence cystoscopy with Hexvix®.
abstract: Fluorescence cystoscopy enhances detection of early bladder cancer. Water used to inflate thebladder during the procedure rapidly contains urine, which may contain fluorochromes. This frequently degradesfluorescence images. Samples of bladder washout fluid (BWF) or urine were collected (15 subjects). We studiedtheir fluorescence properties and assessed changes induced by pH (4 to 9) and temperature (15°C to 41°C).A typical fluorescence spectrum of BWF features a main peak (excitation/emission: 320∕420 nm, FWHM =50∕100 nm) and a weaker (5% to 20% of main peak intensity), secondary peak (excitation/emission: 455∕525 nm, FWHM = 80∕50 nm). Interpatient fluctuations of fluorescence intensity are observed. Fluorescence intensity decreases when temperature increases (max 30%) or pH values vary (max 25%). Neither approach is compatible with clinical settings. Fluorescence lifetime measurements suggest that 4-pyridoxic acid/riboflavin is the most likely molecule responsible for urine’s main/secondary fluorescence peak. Our measurements give an insight into the spectroscopy of the detrimental background fluorescence. This should be included in the optical design of fluorescence cystoscopes. We estimate that restricting the excitation range from 370–430 nm to 395–415 nm would reduce the BWF background by a factor 2.
authors.affiliation: Swiss Federal Institute of Technology (EPFL), Institute of Chemical Sciences and Engineering, Station 6, CH-1015 Lausanne, Switzerland.
authors.forename: Carla
authors.initials: C
authors.lastname: Martoccia
authors.affiliation: Swiss Federal Institute of Technology (EPFL), Institute of Chemical Sciences and Engineering, Station 6, CH-1015 Lausanne, Switzerland.
authors.forename: Matthieu
authors.initials: M
authors.lastname: Zellweger
authors.affiliation: Swiss Federal Institute of Technology (EPFL), Institute of Chemical Sciences and Engineering, Station 6, CH-1015 Lausanne, Switzerland.
authors.forename: Blaise
authors.initials: B
authors.lastname: Lovisa
authors.affiliation: University Hospital (CHUV), Department of Urology, BH-10, Rue du Bugnon 46, CH-1011 Lausanne, Switzerland.
authors.forename: Patrice
authors.initials: P
authors.lastname: Jichlinski
authors.affiliation: Swiss Federal Institute of Technology (EPFL), Institute of Chemical Sciences and Engineering, Station 6, CH-1015 Lausanne, Switzerland.
authors.forename: Hubert
authors.initials: H
authors.lastname: van den Bergh
authors.affiliation: Swiss Federal Institute of Technology (EPFL), Institute of Chemical Sciences and Engineering, Station 6, CH-1015 Lausanne, Switzerland.
authors.forename: Georges
authors.initials: G
authors.lastname: Wagnières
mesh_terms: D000328:Adult; D000368:Aged; D000622:Aminolevulinic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D003558:Cystoscopy / Q000379:methods*; D005260:Female; D005453:Fluorescence; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008875:Middle Aged; D013050:Spectrometry, Fluorescence / Q000379:methods*; D013696:Temperature; D001743:Urinary Bladder / Q000601:surgery*; D014556:Urine / Q000737:chemistry*
chemical_list: D000622:Aminolevulinic Acid; C419924:5-aminolevulinic acid hexyl ester