This lid growth calls for external photography. External photography documents abnormalities of the eye's outer structures. An eyelid tumor is the classic example. These findings do not need high magnification to be seen. A plain picture of the lid records the size, the color, and the exact spot. That image gives the surgeon a clear before picture to compare with the lid after surgery.
The gear is simple. External photography needs only a digital camera with a close-up lens and an electronic flash attachment. Nothing touches the eye, and no eyedrops are required. Match the method to the structure. Slit-lamp photography is for the cornea, angle structures, iris, and lens, because the slit lamp supplies the high magnification those parts need. Fundus photography is for the retina and optic nerve, and it needs dilating drops first. External photography covers everything you can see on the surface: lids, lashes, the white of the eye, and the position of the eyes. Before you shoot, note which eye you are photographing, because the chart needs the correct eye labeled.
Ask one question before you pick a camera. How much magnification does this finding need? A lid lump needs almost none, so photograph it externally. Deeper or smaller targets need the slit lamp or the fundus camera. Include a view of the whole face or both eyes, so a later reader can see where the growth sat. Choosing the right camera for the right structure is part of the COA ophthalmic imaging content area.
Incorrect Answers
- A. Fundus photography images the back of the eye through a dilated pupil. It cannot record a growth sitting on the skin of the eyelid.
- B. Slit-lamp photography is aimed at the front structures of the eye, such as the cornea and iris. It gives far more magnification than this lid lump needs.
- C. Specular microscopy photographs the cells lining the inside of the cornea at very high power. It says nothing about an eyelid growth.
Testing Pearls
- External photography documents the outer structures, such as an eyelid tumor.
- It needs only a digital camera with a close-up lens and flash.
- Slit-lamp photography covers cornea, angle, iris, and lens.
- Fundus photography covers the retina and optic nerve and needs dilation.
- Specular microscopy photographs the cornea's endothelial cells so they can be counted.
References
- American Academy of Ophthalmology. Ophthalmic Medical Assisting: An Independent Study Course. Chapter 10, Adjunctive Tests and Procedures.
