Abstract
Purpose: :
The biomechanical properties of lens and corneal tissue are linked to a number of ocular problems, such as corneal ectasia and presbyopia. Brillouin optical microscopy is a novel technique for probing the mechanical properties of a sample with three-dimensional resolution. Here, we report the first-in-human optical Brillouin-scattering measurement of the anterior segment of the eye.
Methods: :
Brillouin optical microscopy is based on Brillouin light scattering where the interaction between light and tissue gives rise to a small spectral shift that is proportional to the hypersonic elastic modulus. Brillouin optical microscopy measures the Brillouin frequency shift with an ultrahigh-resolution spectrometer in combination with a laser-scanning confocal microscope.
Results: :
We constructed a Brillouin optical scanner safe for human use by employing continuous-wave laser light at 780 nm, low power of 0.7 mW and pixel acquisition time as low as 0.2 s. The instrument featured transverse resolution of less than 5 μm and axial resolution of about 60 μm. With this instrument, we have obtained axial profiles of the Brillouin modulus in the cornea and crystalline lens of healthy human volunteers.
Conclusions: :
We have developed a clinical prototype of Brillouin microscopy and obtained the first-in-human data. Brillouin imaging can quantitatively and safely assess the biomechanical properties of the cornea and lens tissue in human. The work demonstrates the potential of Brillouin microscopy for clinical diagnostics and treatment monitoring.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • laser • anterior segment