Premium
Retinal fluorescence lifetime imaging ophthalmoscopy measures depend on the severity of Alzheimer's disease
Author(s) -
Jentsch Susanne,
Schweitzer Dietrich,
Schmidtke KaiUwe,
Peters Sven,
Dawczynski Jens,
Bär KarlJürgen,
Hammer Martin
Publication year - 2015
Publication title -
acta ophthalmologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.534
H-Index - 87
eISSN - 1755-3768
pISSN - 1755-375X
DOI - 10.1111/aos.12609
Subject(s) - ophthalmoscopy , retinal , medicine , ophthalmology , disease , optometry , pathology
Purpose To determine alterations in the retina of patients with Alzheimer's disease ( AD ) by the newly developed technique of fluorescence lifetime imaging ophthalmoscopy ( FLIO ) in a pilot study. Methods FLIO set‐up uses a scanning laser ophthalmoscope ( HRA 2, Heidelberg Engineering, Germany), which was modified by the use of an excitation pulse laser BLD 440 (Becker&Hickl, Berlin, Germany) and detection of fluorescence lifetime by time‐correlated single photon counting ( TCSPC ; Becker&Hickl) in two spectral channels (channel 1: 490–560 nm, channel 2: 560–700 nm). Least square fit of three exponential functions was used for fluorescence decay analysis. That resulted in three fluorescent components with lifetimes τ i , amplitudes α i and relative contributions Q i . 16 patients with AD (mean age 77.2 ± 7.0 years) were investigated. After regular ophthalmic investigation, FLIO examination and OCT examination were performed. Alzheimer‐specific clinical data were collected ( MMSE , cerebrospinal fluid ( CSF ) concentration of amyloid‐ β (1‐42), total‐tau and phosphorylated tau181 (p‐tau181) protein). Results The FLIO parameters of the second fluorescent component α 2 and Q 2 (channel 2) correlated significantly with MMSE score (Q 2 , R = −0.757, p = 0.007; α 2 , R = −0.618, p = 0.043) as well as p‐tau181‐protein concentration in CSF (Q 2 , R = 0.919, p = 0.009; α 2 , R = 0.881, p = 0.020) in patients with AD . OCT measurements of retinal nerve fibre layer thickness, optic disc excavation and macular thickness neither correlated with Alzheimer‐specific CSF data nor MMSE score. Conclusions Unlike conventional techniques, such as OCT , the new technique of FLIO revealed changes in the retina of patients with AD in relation to Alzheimer‐specific markers in this pilot study.