High-resolution acoustic-radiation-force-impulse imaging for assessing corneal sclerosis

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Medical Imaging

Background:

• Corneal biomechanical properties are crucial for diagnosing pathologies like keratoconus and assessing surgical recovery.
• Noninvasive, high-resolution estimation of corneal stiffness is vital for ophthalmic diagnosis.

Purpose of the Study:

• To establish a high-resolution acoustic-radiation-force-impulse (ARFI) imaging method for assessing corneal stiffness distribution.
• To evaluate the potential of ARFI imaging for detecting corneal sclerosis.

Main Methods:

• Utilized a dual-frequency confocal transducer with an 11-MHz pushing element and a 48-MHz imaging element.
• Employed mechanical B/D scans to correlate tissue displacement with elastic properties for stiffness mapping.
• Verified the system using tissue-mimicking phantoms and ex vivo porcine corneas with induced sclerosis.

Main Results:

• ARFI imaging clearly visualized stiffness distributions in phantoms.
• Measured lateral and axial resolutions were 177 μm and 153 μm, respectively.
• Successfully distinguished localized corneal sclerosis in ex vivo experiments.

Conclusions:

• High-resolution ARFI imaging provides accurate corneal stiffness mapping.
• The developed ARFI method shows significant potential for clinical diagnosis of corneal sclerosis.