Abnormalities of the optic lens are recognized in:

A, B, C i.e. Hypoparathyroidism, Homocystinuria, Congenital rubella - Microspherophakia is usually presence of small, relatively spherical lens with increased A-P thickness and steeper A-P curvatues. It is usually bilateral and may be caused by mesodermal defect, such as Marfan syndrome, WeillMarchesani syndrome and hyperlysinaemia and congenital rubellaQ. It may be a/w Peters anomaly and familial ectopia lentis et pupillae. Microspherophakia causes lenticular myopia and may l/t lens dislocation (usually downward) and pupillary-block. - Abnormalities of central lens curvature include lenticonus (conical) 'and lentiglobus (spherical), and may be anterior or posterior. It may be a/w Alpo's syndrome (familial hemorrhagic nephritis) or Lowe's oculocerebral syndrome (causes posterior lenticonus)Q. They cause lenticular myopia with irregular astigmatism. Lens umblication is depression in the lens surface (usually posteriorly). - Lens coloboma is notching (d/t segmental agenesis) at the inferior equator with corresponding absence of zonular fibers. Cataract is seen in congenital rubella (with salt pepper retinopathy), hypoparathyroidism (with optic disc edema), Wilsons disease (sunflower type) and myotic dystrophyQ.