Confocal scanning in ophthalmology refers to imaging methods that use a confocal optical system to obtain high-resolution, thin optical sections of ocular structures. It is commonly applied to the cornea and retina.
Principles
A confocal setup uses pinholes to reject out-of-focus light, improving contrast and axial resolution. By scanning across the tissue and at different depths, it builds up detailed en face or three-dimensional images.
- Corneal confocal microscopy visualises cells and nerves at near histological resolution
- Scanning laser ophthalmoscopy provides sharp retinal images with reduced scatter
- Techniques may be contact or non-contact depending on the application
- Images can be recorded for longitudinal comparison
Clinical Uses
Confocal imaging assists in diagnosing corneal infections, dystrophies, and neuropathies, and in studying retinal diseases and optic nerve head structure. It is also an important research tool in ocular surface and retinal neuroscience.
- Allows in vivo assessment of corneal nerve density and morphology
- Helps detect organisms such as acanthamoeba or fungi within the cornea
- Provides high-contrast views of microstructures not visible with standard microscopy
- Interpretation requires familiarity with normal and pathological patterns
