A cataract is a common occurrence in an eye clinic. However, there are some unusual forms of lens opacification that are seen infrequently. One such type results in the formation of delicate, multi-colored crystals in the lens. It resembles a lighted christmas tree and is hence called a Christmas tree cataract.

These changes result from an accumulation of cystine or cholesterol in the lens material. Causes include myotonic dystrophy, gout, diabetes with poor control, and increased calcium levels. Occasionally, it can also be an idiopathic age-related change and may affect only one eye.

Recognition of this unusual type of lens change should alert the ophthalmologist to the presence of the aforementioned underlying causes. Relevant investigations are performed to look for and if present, treat the underlying conditions. When visually significant, the cataract is dealt with in the routine manner.