Handling and maintenance
of ophthalmic screening cameras

An ophthalmic camera is a highly specialised optic instrument. The heart of this instrument is a very complex, expensive, and especially for the needs of ophthalmic photography designed lens system.

Since the front lens is the most exposed part and very close to the patient it is the cameras Achilles heel. This lens is especially coated to allow the best possible refraction for the light through the optic system. If the coating is damaged the image quality deteriorates. This will lead to ungradable or less reliable graded images especially in patients with cataracts.

Unfortunately this coating is very fragile and can easily be damaged. It requires a very sensible handling if it needs to be cleaned. The coating will be destroyed if it comes in contact with alcohol or other solvents. Therefore never ever use any solvents to clean the lens and always protect the lens with the lens cap if you clean the camera body and parts that come in contact with the patient.

If there is little dust on the lens always use a bellow and a fine soft brush, available from specialised photo shops. Do not try to blow it off, you could cover the lens with fine drops and these are hard to remove. If there are some spots on the lens you cannot get rid of with the bellow and brush use a special micro fibre cloth, also available from photo shops. Aspirate carefully on the lens and rub very gently with the cloth from the centre of the lens in growing circular movements around the centre of the lens towards its outside. Do not press the cloth too hard against the lens; again, this is a very fragile coating which also can be physically wiped off. If the first wipe wasn't enough repeat the cleaning carefully until a sufficient cleanliness is reached.

But, as one can assume, the less cleaning is necessary the better it is for the lens. So, a careful handling in the daily routine will ensure a low maintenance operation and lower the risk of any damage.

Here are some tips and tricks:

  • Always replace the lens cap between two patients.
  • Position the patient's head before you remove the lens cap.
  • Bring the camera from the outside towards the eye to be photographed;
    this avoids possible contact with the patient's nose.
  • If the patient takes his head off the chin rest pull the camera back to you;
    again, to avoid any possible nose contact.
  • Watch your hand if you replace the lens cap,
    if the lens cap doesn't hit the target your fingers will do it!

© Copyright 2008-2017. The Reading Centre, Moorfields Eye Hospital NHS Trust Foundation. All rights reserved.