biometry A-scan
Ultrasonic measurement technique to determine axial length and other ocular dimensions for IOL power calculation in pediatric patients.
Full Definition
A-scan biometry is a crucial diagnostic procedure in pediatric ophthalmology that uses ultrasonic waves to measure ocular dimensions, particularly axial length, anterior chamber depth, and lens thickness. In children, this measurement is essential for IOL power calculations during cataract surgery and for monitoring eye growth in various conditions. The procedure can be challenging in pediatric patients due to cooperation requirements and the need for precise probe positioning. Immersion A-scan techniques are preferred over contact methods for greater accuracy. Results must be interpreted considering normal pediatric growth patterns, as axial length increases significantly during the first few years of life.
Usage
Usage note: Specify immersion vs. contact technique; document cooperation level in pediatric patients.
In Context
- "Biometry A-scan revealed an axial length of 19.2 mm, appropriate for the child's age and refractive error." — Pre-operative measurement report
- "Serial A-scan biometry demonstrated normal axial growth patterns following congenital cataract surgery." — Follow-up examination notes