Diagnosis
2
Table 2. Types of Cataracts
Nuclear • Central opacification or discoloration
• Accompanied by brunescence, opalescence, or both
• Progress slowly
• Affect distance vision more than near vision
• May induce myopia or a reduction in hyperopia
Cortical • Central or peripheral
• Spoke-like or nummular appearance
• Patients commonly complain of glare
• Sometimes best visualized by retroillumination or
retinoscopy
Posterior subcapsular
cataracts (PSCs)
• Can cause substantial visual impairment if they involve the
axial region of the lens
• More frequent in younger patients than either nuclear or
cortical cataracts
• Patients often have glare and poor vision in bright light,
and near vision is typically more affected than distance due
to miosis with near accommodation
Î Each type of cataract has its own anatomical location, pathology, and
risk factors for development. Several systems are available to classify
and grade lens opacities, but variations in grading systems make
comparing prevalence rates between studies difficult.
