This patient's clinical presentation is consistent with a senile cataract, or opacification of the lens due to age.
Senile cataracts are the leading cause of visual impairment worldwide, affecting approximately 17% of people older than 40 years and 50% of people over the age of 75 years. Senile cataracts are due to the denaturation of lens proteins, leading to opacification of the lens. Although it is a natural phenomenon that occurs as the lens ages, the rate of formation of cataracts can be increased by systemic diseases, such as diabetes and hypertension, as well as environmental factors, such as UV light and radiation exposure. Although age-related cataracts are most common, they can also be caused by corticosteroid use, certain genetic diseases, and trauma.
Pelletier et al. review visual loss in elderly patients. They state that people over the age of 65 years should be screened for visual problems every 1 to 2 years, as 40-50% of the causes of visual impairment can be treated or prevented. They state that cataracts can be followed by a primary care doctor if they are not visually significant, but should be evaluated by an ophthalmologist if they become visually impairing.
Alio et al. review the treatment of catarcts with phacoemulsification with intraocular lens (IOL) implantation surgery. They state that the primary goal of surgery is to achieve emmetropia (a refractive outcome that does not require correction). Emmetropia has been found to be achieved in only approximately 55% of eyes. They explain that the residual refractive error can be corrected by LASIK surgery, as well as other procedures.
Figure A shows a magnified view of the eye as seen through a slit-lamp. Through the pupil, a clouding of the lens can be seen. Illustration A depicts an algorithm for evaluating elderly patients with visual loss.
Answer 1: Retinal detachment typically presents unilaterally with flashes of light, floaters, followed by visual loss.
Answer 2: Age-Related Macular Degeneration (AMD) is differentiated into wet and dry AMD. Wet AMD is due to neovascularization and dry is characterized by drusens between the retina and choroid. AMD leads to gradual visual loss, decreased color vision, and increased risk for retinal detachment. This patient's presentation and exam is more consistent with cataracts than with AMD.
Answer 3: Diabetic retinopathy is a common disease that leads to blurred vision and blindness. This patient is does not have a history of diabetes.
Answer 5: Cataracts are due to opacification of the lens, not the cornea.
Pelletier AL, Thomas J, Shaw FR. Vision loss in older persons. Am Fam Physician. 2009 Jun 1;79(11):963-70. PubMed PMID: 19514694.
PMID:19514694. (Link to Abstract)
Alio JL, Abdelghany AA, Fernández-Buenaga R. Management of residual refractive error after cataract surgery. Curr Opin Ophthalmol. 2014 Jul;25(4):291-7. doi: 10.1097/ICU.0000000000000067. Review. PubMed PMID: 24865171.
PMID:24865171 (Link to Abstract)