Casualty First is now open on an appointment only basis, Monday to Friday 8am – 6pm and Saturday 12th/19th of December 8am – 6pm.
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We are offering Outpatient appointments. In many cases these can be conducted virtually. To make an appointment, please call: 0207 806 4060.
Do NOT visit the Hospital if you have any COVID-19 symptoms. Please visit the Track and Trace website.
A-scan ultrasound biometry is a routine diagnostic test, which provides data on the length of the eye (a major factor in many sight disorders).
In ophthalmology, the A-scan is most commonly used to determine eye length for intraocular lens power calculation.
When a cataract is removed, the lens is replaced by an artificial lens implant and by measuring the length of the eye as well as the power of the cornea (keratometry) your specialist can calculate the required power of the intraocular lens.
Another common use of the A-scan is determining the size and ultrasound characteristics of masses in the eye, from which the type of mass can be deduced.