Related Experiment Videos
In vitro flow properties of glaucoma implant devices
D L Eisenberg1, E Y Koo, G Hafner
1New England Eye Center, Tufts University School of Medicine, Boston, MA 02111, USA.
Ophthalmic Surgery and Lasers
|October 3, 1999
Summary
This study developed a new protocol to test glaucoma implant devices. The Ahmed glaucoma valve showed consistent performance, but no device fully explained clinical failures.
Area of Science:
- Ophthalmology
- Biomedical Engineering
- Medical Device Testing
Background:
- Glaucoma drainage devices are crucial for managing intraocular pressure.
- Standardized testing protocols are needed to evaluate the performance of these implants.
- Existing devices exhibit variable performance characteristics.
Purpose of the Study:
- To establish a reliable protocol for testing glaucoma implant devices.
- To characterize the performance of currently available glaucoma implant devices using the developed protocol.
Main Methods:
- Utilized an open-manometer system for real-time pressure monitoring during fluid perfusion.
- Tested five different glaucoma implant devices: Ahmed, Baerveldt, Krupin, Joseph, and OptiMed.
- Measured pressure per unit time over a 10-minute interval with constant fluid flow, averaging four runs per device.
Main Results:
- Ahmed devices demonstrated consistent valve performance (opening pressure: 13.65 mm Hg).
- Baerveldt and OptiMed devices showed very high facility of flow.
- Joseph and Krupin devices exhibited variable performance; only Ahmed showed consistent valve behavior.
Conclusions:
- A robust objective test protocol for glaucoma implant devices was successfully demonstrated.
- All tested devices exhibited high facility of flow, with Ahmed being the only one with consistent valve action.
- The study suggests that device resistance alone does not fully explain long-term clinical failures in glaucoma drainage surgery.