<prompt> Polychromatic luster is a feature ofNuclear cataractCortical cataractZonular cataractComplicated cataract  <response>: Ans. d Complicated cataract Ref. Basaks ophthalmology 2nd ed., 181COMPLICATED CATARACTS It is a complication of any protracted intraocular inflammation, especially heterochromia, chronic iridocyclitis, retinal vasculitis, and retinitis pigmentosa. Complicated cataract results from a disturbance of the lens metabolism due to inflammatory or degenerative diseases. The result is a pumice-like posterior subcapsular cataract that progresses axially toward the nucleus. Vision is much impaired even in early stage, due to position of the opacity near nodal point of eye. The opacity usually commences in posterior cortex in the axial plane posterior cortical cataract. The opacity appears grayish with bread-crumb appearance in oblique illumination. This form of cataract produces extreme light scattering. On slit lamp, the opacity shows a characteristic rainbow display of colors, the polychromatic luster. Rx: Operative and visual prognosis in complicated cataract is usually poor.Note: Riders spoke wheel are seen in lamellar cataract, which is the most common type of congenital cataract. 