Christmas tree cataract.

A sixty-year-old female presented for a routine eye check-up. Her best corrected visual acuity was 6/6 in both eyes. Slit lamp examination after pupillary dilatation displayed vivid multi-coloured glistening opacities in the otherwise clear lens of her left eye (Fig. 1A). A magnified view using direct focal illumination revealed a spectacular array of polychromatic needle shaped crystals traversing all directions and cutting across the natural limits of the lens fibres, located in the deep cortex and anterior nucleus of the lens, giving the appearance of coloured lights decorating the branches as on a Christmas tree (Fig. 1B). The colours of the crystals varied according to the angle of the incident light. In retroillumination only a dim outline of the cataract was seen. The right eye examination was unremarkable. The patient had no other notable ocular or systemic abnormality. A diagnosis of uniocular “Christmas tree” cataract was made. In view of the excellent visual acuity, the patient was advised regular follow-up.

Figure 1

(A) Glistening opacities visible in the lens of the left eye on diffuse illumination. (B) A magnified view using direct focal illumination showed multiple polychromatic needle shaped crystals traversing all directions, cutting across the natural limits of the lens fibres.

Comment

A Christmas tree cataract is a rare age-related change resulting from accelerated breakdown of membrane-associated denatured proteins induced by elevated calcium levels. The peptides and amino acids accumulate in the lumen of the reticular meshwork, and cysteine is concentrated beyond the level of crystallisation causing the formation of needles, that impart the fascinating appearance of a Christmas tree in the eye.1, 2 Christmas tree cataracts have also been seen in patients with myotonic dystrophy. This striking appearance can surprise an ophthalmologist, when picked up on routine eye examination.

Conflict of interest

The author declares that there is no conflict of interest.