Christmas Tree Cataract
Christmas tree cataract is a rare type of lens opacification which is usually age-related, though several cases have been seen in patients with myotonic dystrophy. It consists of highly refractive multicoloured needle-shaped opacities within the deep cortex of the lens (1). The mechanism of crystals is not exactly known, but different theories have been proposed. Shun-Shin et al. postulated that the crystals were most likely of cystine due to an age-related aberrant breakdown of the lens, induced by elevated Ca++ levels (1). According to Anders and Wollensak, the crystals were cholesterol in nature and were the result of lens metabolism (2). A 64 years old female presented with reduced visual acuity in her right eye. Her best-corrected visual acuity (BCVA) in the right eye was 6/10 Snellen chart. Slit-lamp examination after pupillary dilatation revealed highly reflective, polychromatic, needle-shaped crystals in the temporal and inferior cortex of the right lens with associated nuclear sclerosis. This aspect of glittering multi-coloured opacities varying with the angle of light incidence resembles the coloured lights decorating the Christmas tree (Figure 1, Figure 2). As the visual acuity was significantly reduced and there were no other associated ocular pathologies, we decided for cataract surgery in the right eye. Since the crystals are highly refringent and change considerably the viewing of the surgeon during the procedure, an increased time of surgery should be avoided (3), (4). Uneventful extracapsular phacoemulsification of the lens with artificial monofocal lens implantation within the capsular bag was performed with very good results.
G. Adrien Shun-Shin* Gijs F. J. M. Vrensen, Nicholas P. Brown,* Ben Willekens,^. Morphologic Characteristics and Chemical Composition. Investigative Ophthalmology & Visual Science. December, 1993, Vol. 34, 13.
Anders N, Wollensak J. [Christmas tree ornament cataract--an indication for disordered lipid metabolism?]. Klin Monbl Augenheilkd. 1992, 201.
Larissa Rossana Souza Stival, Ricardo Henrique Goulart Bittar,Anelise Medeiros Lago,João Jorge Nassaralla Junior. Christmas tree cataract. Revista Brasileira de Oftalmologia. Sept/Oct, 2015, Vol. 74.