Zonular cataract Nuclear cataract 2010-05-28T11:34:45Z Yellowish cloudy centre of lens A nuclear cataract is an opacity or clouding that develops in the lens nucleus. That is, a nuclear cataract is one that is located in the center of the lens. The nucleus tends to darken changing from clear to yellow and sometimes brown. Yellowish cloudy center of lens HP:0007672 HP:0008024 HP:0007781 SNOMEDCT_US:53889007 HP:0100018 UMLS:C0392557