Second harmonic generation imaging of the pig lamina cribrosa using a scanning laser ophthalmoscope-based microscope.
We describe a novel scanning laser ophthalmoscope (SLO)-based on a video-rate second harmonic generation imaging microscope. A titanium:sapphire femtosecond laser was coupled to a modified SLO. The laser beam was scanned over the sample, and the light produced by second harmonic generation (SHG) was collected for imaging at video-speed. The device was used for imaging the lamina cribrosa (LC) of enucleated pig eyes. A resolution comparable to that of commercial multiphoton microscopes was reached. The SHG images were used for determining the average pore size of the LC determined from the images; the pressure dependence of the pore size was studied by the artificial increasing of the hydrostatic pressure in the eye. A pressure increase of 44.3 mmHg enlarged the average pore size of 62 analyzed pores by a statistically significant amount. The relative pore growth was measured at four different pressure levels in 25 pores. The pressure was increased in 15 mmHg steps. A general tendency for monothonic growth was observed, although single pores grew by no means linearly.
Agopov
M
M
Kirchhoff-Institut für Physik, INF 227, Heidelberg, Germany. mikael.agopov@iki.fi
Lomb
L
L
La Schiazza
O
O
Bille
J F
JF
D000818:Animals; D007091:Image Processing, Computer-Assisted; D007429:Intraocular Pressure; D018613:Microscopy, Confocal / Q000295:instrumentation / Q000379:methods; D023421:Models, Animal; D019721:Ophthalmoscopes; D009887:Ophthalmoscopy / Q000379:methods*; D009898:Optic Disk / Q000033:anatomy & histology* / Q000502:physiology; D034421:Sus scrofa / Q000033:anatomy & histology*