aCase 12 Answers

by Dr.Chua

A 53-year-old man complained of decreased left vision for the past 12 months. Examination showed right vision 6/12 and left 6/24. Nuclear sclerosis were seen in both eyes more on the right than the left. The following was the appearance of the left eye after pupil dilatation (Figure 1)
 

Figure 1.

a. What is the diagnosis?

Left lens coloboma.

Coloboma of the lens is not a true coloboma.  Instead the notch in the equator resulted from an absence of zonular fibers from an underlying colobomatous ciliary body. This absence results in a lack of tension on the lens capsule in that region. The lens tissue is not missing. 

b.Is systemic association common with this condition?

This condition is usually isolated. The majority of lens coloboma occurs  in the inferior nasal quadrant (“typical” area of coloboma) and may be associated with iridic or other colobomas along the old fetal fissure pathway. Other authors believe coloboma of the lens is an incomplete form of ectopia lentis. There are reports of lens coloboma in patients with Marfan's syndrome.

Reference:

1. Ilsen PF, Patel S. Coloboma of the crystalline lens. Optometry. 2003 Dec;74(12):765-74.

2. Mehrotra AS, Solanki N, Sabharwal KK. Bilateral coloboma of lens in Marfan's syndrome. Indian J Ophthalmol. 1985 May-Jun;33(3):201-2.