The UV Burton lamp is a portable, hand-held, ultraviolet lamp used to examine the external ocular surface. It has a black rectangular plastic housing containing an optically ground and polished magnifying lens of +4D to +5D strength with dimensions of 10cm by 7cm providing a clear viewing area. In addition, it includes 2 white fluorescent bulbs and 2 ultraviolet (UV) bulbs to examine the eye under white light and UV light respectively.
USES OF THE UV BURTON LAMP
- Traditionally, this instrument is used for observing the fit of hard contact lenses using fluorescein dye instilled in the eye.
- Eye injuries are also observed under white light as well as UV light.
- Visual assessments of the ocular adnexa such as lids, lashes are easily facilitated by employing the UV Burton lamp.
- A huge advantage of the UV lamp is the large field of view of the magnifying lens that allows both eyes to be examined simultaneously. This helps to judge and observe asymmetries such as anisocoria, heterochromia, unilateral constant strabismus and alternating strabismus.
- Sometimes, it is difficult to fit contact lenses or examine the eyes of patients of extreme physical stature using a slit-lamp biomicroscope, especially when positioning these patients in the chin rest comfortably. The UV Burton lamp is amenable to the examination of infants, petite individuals and extremely burly adults.
- Children need to be examined efficiently and rapidly and this instrument assists in this regard significantly.
- This lamp can be used to measure and observe pupil size in dim illumination. The fluorescence of the crystalline lens, in ultraviolet light, makes the measurement of the pupils much easier when utilising the UV Burton lamp.
LIMITATIONS OF THE UV BURTON LAMP
- The major limitations of the lamp include the lack of variable illumination and magnification control that are present in slit-lamp biomicroscopes. Van Herick angle assessment is not possible and slit beam dimension controls are not present.
- It is an ineffective method of observing the fluorescein pattern of gas permeable materials with UV-absorbing properties. This is as a result of the decreased fluorescence that occurs when short-wavelength blue light is attenuated by the lens material, because the Burton lamp has its highest wavelength in the 300 to 400nm range.
The UV Burton lamp is an inexpensive and simple tool that allows a good overall view of eye and external ocular structures. In addition, it has a useful magnification lens and a large field of view.
- Sclafani LA. Fitting infants with contact lenses. Contact Lens Spectrum November 2004.
- Grosvenor TP. Primary Care Optometry. 5th ed. St Louis: Butterworth Heinemann, 2007, 122.