Eye Diagnostics & Pharmacokinetics

Diagnosing physiological conditions via the eye

Lein is applying its experience in optics, ophthalmology and medical devices to develop new technologies that can examine physical attributes of the body. The primary advantage is that the method used is non-invasive and there is no need to draw blood to take a measurement - so there is no pain for the patient and greater ease of use for the point of care professional.

Lein’s technology works by first shining a low power beam of light into the eye then by analysing the reflected signal. This gives direct information on the structure of the eye but also on the health of the body. The eye, often called the "window to the soul", is in practice the window to your health.

Pharmacokinetics

Pharmacokinetics is the measurement of the absolute level of, and the diffusion characteristics of, pharmaceutical drugs within the body. Lein’s technology has the potential to make these measurements non-invasively and this is of great interest to the pharmaceutical industry.

Lein has put together a collaboration with Durham University, who have expertise in optical measurements on the body, Strathclyde University, who have expertise in pharmacokinetics via the eye, and a large US pharmaceutical company who wish to use the technology to gain a better understanding of their drug’s performance.

An EPSRC CASE award studentship has been set up at Durham University with the aim of adapting Lein’s technology to the detection and monitoring of pharmaceutical drugs non-invasively, in the anterior segment of the eye.

The team at Durham University have built an instrument capable of tracking the diffusion of fluorescent drugs in the eye. The instrument is based on a confocal fluorescent scanning microscope and is a design adapted from one of Lein's instruments.

The focus of a laser (λ = 405nm) is scanned through the anterior chamber along the optical axis. Fluorescent light within a specific wavelength range excited by the laser is returned from the eye and recorded and analysed by the instrument.

The instrument, which has already been evaluated in-vitro, is extremely sensitive and can detect Fluorescein concentrations lower than 10nM / L. It is also fast with data being acquired at a speed of up to 1kHz. These in vitro tests have demonstrated the ability of the meter to track the diffusion of a drop of Fluorescein with an axial resolution of 200 µm. The next step is to evaluate the instrument’s performance on perfused bovine eyes followed by clinical trials on human volunteers