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We recently reported on two new gadgets designed to fit onto the eyepiece of a slit lamp to allow the correct positioning of an iPhone 4S to capture stills and video footage of the eye under examination. The resolution of these modern phone cameras is excellent and so this option provides a cheap and flexible alternative to the dedicated slit-lamp anterior imaging systems currently in use.

For this series of images I used the EyePhoneDoc (Figure 1) and an LED positional backlighter which is flexible to position anywhere on a standard (that is, non-photographic) slit lamp (Figure 2). I downloaded an app called 'camera +' for less than £1. This enhances the autofocus and offers more options on light adjustment and focusing than the standard program included with the phone.

As I found before, it is worth spending a little time positioning the device as accurately as possible and then only a small circular image appears on the phone screen. Do not magnify at this stage as significant definition will be lost. Instead, focus and capture and then, in the camera + device, use the editing, brightness adjustment and cropping options to maximise the view of the image. Figure 3 shows an overview of an eye using simply the backlighter. Slit-lamp light here would cause local bleaching of the image. Figures 4a and 4b show early pinguecula and conjunctival hyperaemia (the patient had had a sleepless night prior to the examination). Figures 5a and b show with mixed success an attempt to capture the tear prism, either with a small known size light benchmark or without. Figure 6 a is simply a corneal section but underlines that the sensitivity of these cameras is actually rather good. Figure 6b is an attempt at capturing a van Herick view. Grading of a still image is much easier than on the live person. Figure 7 shows early lens brunescence. Any view behind the plane of the iris is best captured without the backlighter in place.

Figure 8a shows the search for anterior chamber activity. Despite peripheral reflections, the gap between the corneal reflection and the lens reflection is clear. Figure 8b shows an attempt at Smith's method whereby horizontal reflections from the beam set at 60 degrees temporal to the eye may be aligned and the height of the beam on alignment directly related to anterior chamber depth.

In the final gallery of smart phone images I will be showing staining assessment and Volk lens views. ●

● Further information on the EyePhotoDoc from www.eyephotodoc.com