Familial Congenital Megalocornea and Spherophakia: A Case Series

Background

Megalocornea is a rare, nonprogressive, congenital defect characterized by enlargement of the corneal diameter greater than 13 mm at birth. The involvement is typically bilateral but can be asymmetric. The anterior segment is widened at the expense of the vitreous length and the intraocular pressure is normal. The defect falls into the category of anterior segment dysgenesis and may be associated with several other conditions, including arcus lipoides, mosaic corneal dystrophy, or iris atrophy and transillumination. The disease is generally asymptomatic in childhood, although the astigmatism due to the large cornea can lead to blurred vision. Nevertheless, patients with megalocornea are prone to zonular deficiencies and subluxation of the lens. Adults may experience premature nuclear sclerotic cataract formation, typically between the ages of 30 and 50 [1], [2].

Megalocornea was first described in 1869, but the genetic basis of this disease has only been elucidated in the past decade. In 90% of the cases, males are affected, since the observed inheritance pattern is predominantly x-linked [3]. In early childhood its differentiation from glaucoma-associated buphthalmos can be challenging [4], [5]. In some patients, megalocornea may also be associated with different congenital syndromes such as Marfan syndrome, or Neuhauser syndrome (megalocornea-mental retardation syndrome) [2], [6].

Publication History

Received: 01 July 2020

Accepted: 06 January 2021

Article published online:
22 February 2021

• References

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