|LETTER TO THE EDITOR
|Year : 2022 | Volume
| Issue : 2 | Page : 260
Widefield examination of the fundus with the portable slit lamp
Jagdeep Singh Gandhi
JSG,Worcester Royal Eye Unit, Worcestershire Royal Hospital, Worcester, United Kingdom
|Date of Submission||10-Mar-2022|
|Date of Decision||13-Apr-2022|
|Date of Acceptance||13-May-2022|
|Date of Web Publication||29-Jun-2022|
Dr. Jagdeep Singh Gandhi
Worcester Royal Eye Unit, Worcestershire Royal Hospital, Worcester
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Gandhi JS. Widefield examination of the fundus with the portable slit lamp. Oman J Ophthalmol 2022;15:260
To the Editor,
Periodically, a doctor has to see a patient who is not examinable at the slit lamp. It may be that the patient cannot reach the slit lamp. It may be that the patient is unwell and bedbound. Hence the resort is equipment of the portable variety. The portable slit lamp allows viewing of the anterior eye, but a survey of the fundus is variable, relying as it does on indirect ophthalmoscopy.
The mobile phone has led to a variation on the theme, whereby a smartphone, on video setting, peers into the eye with a 20D lens and photographs the fundus. The drawback, though, is that the fundus sampling is partial, the view being the posterior pole and some extramacular fundus, a capture of about 30°–60°. Furthermore, whether it is used with a smartphone or an indirect ophthalmoscope, the 20D lens may only show glimpses of the peripheral fundus. Also, when a light is shone into the eye through a 20/28D lens, the brightness may be too uncomfortable. The fundal view can thus be limited, and a failure to see peripheral retina leads to a missing of pathology.
Over the years, I have found the above routine to be inadequate for wheelchaired patients or for those located outside the ophthalmic department. Necessity is the mother of invention, and so I have devised a method to improve the view of the fundus when using portable kit. The method, while helpful, is suited largely to the examination of adult patients. It employs of a portable slit lamp combined with a widefield contact lens. The widefield lenses are readily available in eye services and designed for a lasering of the peripheral fundus. Examples include Super Quad 160 and the Mainster 165. After dilating the pupil, the lens is rested on the cornea with gel, and the lens should be tolerable if a doctor is gentle and speaks kindly. It is seen that, with such a lens, the fundal view is both stable and extensive (160°–180°).
For the wheelchaired patient, the head is rested back on a pillow that is held by another person. Once the widefield lens is applied the slit-lamp hovers over the eye until the fundus sweeps into sight. As at other times, where the portable slit lamp is used, the issue is the weight of the slit-lamp as it is held in the hand. Since the lamp is heavy, and held in mid-air, the result is a tremor, so that the view of the eye is not stationary.
The unsteadiness of the slit lamp is solved by using an arm-sling, like the one that cradles a broken arm, so that, as the lamp is held, the forearm is steady and supported. A comfortable doctor is better able to perform an inspection of the fundus. Lightweight slit lamps, shaped like a mini-torch, are in fact on the market, but these are not common place. Finally, adjustable arm-slings are cheap and worth buying to optimize a portable set-up for examining the eye.
| References|| |
Haddock LJ, Kim DY, Mukai S. Simple, inexpensive technique for high-quality smartphone fundus photography in human and animal eyes. J Ophthalmol 2013;2013:518479.