The Oscillation of Crystalline and Intraocular Lenses

The crystalline lens of the human eye helps to sharpen vision. There can be issues with the support/stability of the lens. This could be seen with the naked eye of an external observer or with the use of a slit lamp. Certain eye conditions can predispose to issues with lens stability. If patients have stability issues with their natural lens- this would be termed as "phakodonesis". However, in patients who have had prior cataract surgery with implantation of an artificial lens (IOL)- this would be termed as "pseudophakodonesis". Eye conditions such as pseudoexfoliation or Marfan-syndrome can lead to unstable lens support- this can be detected if there are advanced stability issues. However, small instability in the eye's would not be detected with present descriptive methods. The authors have designed a high-speed camera which is able to detect stability of the lens, especially during eye movements. The high-speed camera can detect variation in the change of light reflex from the lens and calculate the amount of lens instability/oscillation. The results (in normal eyes) of this high-speed camera has already been published in a peer-review journal. It is non-contact and measures lens movement. The test lasts less than 5 minutes. Further research is required to assess the amount of lens oscillation (wobbling) in different eye populations - patients with previous cataract surgery (an artificial implant is used to replace the lens) or eye conditions (such as pseudoexfoliation, Marfan syndrome). The amount of lens stability has a role in the planning of further intraocular surgery - especially cataract extraction - however, at present, there is no approved quantitative measurement for this. Participants will be recruited through Anglia Ruskin University (educational establishment), local community groups, and through Southend University Hospital eye clinics (NHS organisation). Participants' data will remain anonymous.