Product Description

Immersion A-scan is the accuracy standard for axial length, and the Prager Shell® is the piece that makes it practical chairside. First introduced by Thomas C. Prager, PhD, MPH in 1982 and later refined with Eye Surgical Instruments, the Prager Shell is now used in thousands of ophthalmology clinics worldwide. This P-103GS model is the version sized for a 14.9 mm probe — built for the Sonomed MV-4500 (Mastervue) and other A-scans that use a 14.9 mm probe diameter.

The design does the alignment for you. Internal guide rings hold the ultrasound probe perpendicular to the eye and are vented to keep fluid moving and prevent air bubbles from forming in the lower chamber — two of the most common sources of error in immersion scanning. The clear shell lets you see shell placement and fluid level directly, and because it’s an immersion technique, there’s no need for expensive ultrasound gel and the measurement isn’t limited by media density the way contact scanning can be.

It’s also built for real clinic hygiene and throughput. The shell is autoclavable for reuse, while a side Luer connection allows quick, simple replacement of the disposable tubing between patients to reduce the risk of cross-contamination. This kit includes 25 disposable tubes to get you started, and replacement tube kits keep the per-patient cost low. Immersion biometry with the Prager Shell is clinically equivalent in accuracy to optical biometry, making it a dependable option across your cataract and IOL-planning workflow.

Key features

• Immersion biometry shell for accurate, repeatable axial-length A-scan measurement
• Sized for a 14.9 mm probe — fits the Sonomed MV-4500 (Mastervue) and other 14.9 mm A-scans
• Internal guide rings keep the probe perpendicular; vented to prevent air bubbles
• Clear shell for direct view of placement and fluid level
• Gel-free immersion technique; not limited by media density
• Autoclavable shell; side Luer connection for quick tubing replacement
• Includes a 25-tube kit; low-cost replacement tubes available
• Accuracy clinically equivalent to optical biometry

Frequently Asked Questions

Which A-scan is the Prager Shell P-103GS compatible with?

The P-103GS is sized for a 14.9 mm probe. It fits the Sonomed MV-4500 (Mastervue) A-scan and other A-scan biometers that use a 14.9 mm probe diameter. If you’re unsure of your probe diameter, confirm it before ordering.

Why use an immersion shell instead of contact A-scan?

Immersion biometry avoids compressing the cornea, which improves axial-length accuracy, and it isn’t limited by media density the way contact scanning can be. The Prager Shell’s guide rings also keep the probe perpendicular for consistent, repeatable scans — with accuracy clinically equivalent to optical biometry.

Is the Prager Shell P-103GS autoclavable, and what’s included?

Yes, the shell is autoclavable for reuse. This kit includes 25 disposable tubes, which are replaced between patients via the side Luer connection to reduce the risk of cross-contamination. Replacement tube kits are available separately.

Does it require ultrasound gel?

No. The Prager Shell uses an immersion technique with fluid in the shell, so it does not require ultrasound gel. The clear shell lets you monitor fluid level and placement directly during the scan.

Is it in stock, and how do I order?

Yes, this kit is new and in stock. Add it to your cart to order. For questions on compatibility with your specific A-scan, contact Optimetrics at +1 (305) 542-7556 or sales@optimetrics.com.