Assessment of rat and mouse RGC apoptosis imaging in vivo with different scanning laser ophthalmoscopes.
OBJECTIVE
We have recently described a novel way of imaging apoptosing retinal ganglion cells in vivo in the rat. This study investigated if this technique could be used in the mouse, and whether the Heidelberg Retina Angiograph II (HRAII) was appropriate.


METHODS
Retinal ganglion cell (RGC) death was induced by intravitreal injections in rat and mouse eyes using staurosporine. Fluorescent-labeled apoptosing cells were detected by imaging with both the HRAII and a prototype Zeiss confocal scanning laser ophthalmoscope (cSLO). Averaged in vivo images were analyzed and results compared with histologic analysis.


RESULTS
Fluorescent points (FPs) used as a measure of RGC apoptosis in vivo were detected in the mouse eye but only with the HRAII and not the Zeiss cSLO. The HRAII was able to detect 62% more FPs in rat than the Zeiss cSLO. Both cSLOs showed peak FP counts at the 5- to 10-microm range in rat and mouse. Maximal FP counts were detected in the superior and superior temporal regions in the rat, with no obvious pattern of distribution in the mouse. The HRAII was found to have more FP correspondence with histologically identified apoptosing RGCs.


CONCLUSIONS
To our knowledge, this is the first demonstration of visualized apoptosing RGC in vivo in a mouse. The improved image quality achieved with the HRAII compared with the Zeiss cSLO was validated by histology. This together with its enhanced maneuverability and the fact that it is already commercially available make the HRAII a potential tool for the early detection and diagnosis of glaucomatous disease in patients.
Maass
Annelie
A
Glaucoma & Retinal Neurodegeneration Research Group, Institute of Ophthalmology, University College London, London, United Kingdom.
von Leithner
Peter Lundh
PL
Luong
Vy
V
Guo
Li
L
Salt
Thomas E
TE
Fitzke
Frederick W
FW
Cordeiro
M Francesca
MF
D000792:Angiography / Q000295:instrumentation; D000818:Animals; D017209:Apoptosis; D005453:Fluorescence; D051379:Mice / Q000502:physiology*; D018613:Microscopy, Confocal / Q000295:instrumentation*; D019721:Ophthalmoscopes / Q000145:classification*; D051381:Rats / Q000502:physiology*; D015203:Reproducibility of Results; D012160:Retina / Q000000981:diagnostic imaging; D012165:Retinal Ganglion Cells / Q000502:physiology*; D012542:Scattering, Radiation