Senile Cataract Clinical Presentation

  • Author: Vicente Victor D Ocampo Jr, MD; Chief Editor: Hampton Roy Sr, MD   more...
 
Updated: Mar 9, 2012
 

History

Careful history taking is essential in determining the progression and functional impairment in vision resulting from the cataract and in identifying other possible causes for the lens opacity. A patient with senile cataract often presents with a history of gradual progressive deterioration and disturbance in vision. Such visual aberrations are varied depending on the type of cataract present in the patient.

Decreased visual acuity

Decreased visual acuity is the most common complaint of patients with senile cataract. The cataract is considered clinically relevant if visual acuity is affected significantly. Furthermore, different types of cataracts produce different effects on visual acuity.

For example, a mild degree of posterior subcapsular cataract can produce a severe reduction in visual acuity with near acuity affected more than distance vision, presumably as a result of accommodative miosis. However, nuclear sclerotic cataracts often are associated with decreased distance acuity and good near vision.

A cortical cataract generally is not clinically relevant until late in its progression when cortical spokes compromise the visual axis. However, instances exist when a solitary cortical spoke occasionally results in significant involvement of the visual axis.

Glare

Increased glare is another common complaint of patients with senile cataracts. This complaint may include an entire spectrum from a decrease in contrast sensitivity in brightly lit environments or disabling glare during the day to glare with oncoming headlights at night.

Such visual disturbances are prominent particularly with posterior subcapsular cataracts and, to a lesser degree, with cortical cataracts. It is associated less frequently with nuclear sclerosis. Many patients may tolerate moderate levels of glare without much difficulty, and, as such, glare by itself does not require surgical management.

Myopic shift

The progression of cataracts may frequently increase the diopteric power of the lens resulting in a mild-to-moderate degree of myopia or myopic shift. Consequently, presbyopic patients report an increase in their near vision and less need for reading glasses as they experience the so-called second sight. However, such occurrence is temporary, and, as the optical quality of the lens deteriorates, the second sight is eventually lost.

Typically, myopic shift and second sight are not seen in cortical and posterior subcapsular cataracts. Furthermore, asymmetric development of the lens-induced myopia may result in significant symptomatic anisometropia that may require surgical management.

Monocular diplopia

At times, the nuclear changes are concentrated in the inner layers of the lens, resulting in a refractile area in the center of the lens, which often is seen best within the red reflex by retinoscopy or direct ophthalmoscopy.

Such a phenomenon may lead to monocular diplopia that is not corrected with spectacles, prisms, or contact lenses.

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Physical

After a thorough history is taken, careful physical examination must be performed. The entire body habitus is checked for abnormalities that may point out systemic illnesses that affect the eye and cataract development.

A complete ocular examination must be performed beginning with visual acuity for both near and far distances. When the patient complains of glare, visual acuity should be tested in a brightly lit room. Contrast sensitivity also must be checked, especially if the history points to a possible problem.

Examination of the ocular adnexa and intraocular structures may provide clues to the patient's disease and eventual visual prognosis.

A very important test is the swinging flashlight test which detects for a Marcus Gunn pupil or a relative afferent pupillary defect (RAPD) indicative of optic nerve lesions or diffuse macular involvement. A patient with RAPD and a cataract is expected to have a very guarded visual prognosis after cataract extraction.

A patient with long-standing ptosis since childhood may have occlusion amblyopia, which may account more for the decreased visual acuity rather than the cataract. Similarly, checking for problems in ocular motility at all directions of gaze is important to rule out any other causes for the patient's visual symptoms.

Slit lamp examination should not only concentrate on evaluating the lens opacity but the other ocular structures as well (eg, conjunctiva, cornea, iris, anterior chamber). Corneal thickness and the presence of corneal opacities, such as corneal guttata, must be checked carefully. Appearance of the lens must be noted meticulously before and after pupillary dilation.

The visual significance of oil droplet nuclear cataracts and small posterior subcapsular cataracts is evaluated best with a normal-sized pupil to determine if the visual axis is obscured. However, exfoliation syndrome is appreciated with the pupil dilated, revealing exfoliative material on the anterior lens capsule.

After dilation, nuclear size and brunescence as indicators of cataract density can be determined prior to phacoemulsification surgery. The lens position and integrity of the zonular fibers also should be checked because lens subluxation may indicate previous eye trauma, metabolic disorders, or hypermature cataracts.

The importance of direct and indirect ophthalmoscopy in evaluating the integrity of the posterior pole must be underscored. Optic nerve and retinal problems may account for the visual disturbance experienced by the patient. Furthermore, the prognosis after lens extraction is affected significantly by detection of pathologies in the posterior pole preoperatively (eg, macular edema, age-related macular degeneration).

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Causes

Numerous studies have been conducted to identify risk factors for development of senile cataracts. Various culprits have been implicated, including environmental conditions, systemic diseases, diet, and age.

West and Valmadrid stated that age-related cataract is a multifactorial disease with different risk factors associated to the different cataract types.[14] In addition, they stated that cortical and posterior subcapsular cataracts were related closely to environmental stresses, such as ultraviolet (UV) exposure, diabetes, and drug ingestion. However, nuclear cataracts seem to have a correlation with smoking. Alcohol has been associated with all cataract types.

A similar analysis was completed by Miglior et al.[15] They found that cortical cataracts were associated with the presence of diabetes for more than 5 years and increased serum potassium and sodium levels. A history of surgery under general anesthesia and the use of sedative drugs were associated with reduced risks of senile cortical cataracts. Posterior subcapsular cataracts were associated with steroid use and diabetes, while nuclear cataracts had significant correlations with calcitonin and milk intake. Mixed cataracts were linked with a history of surgery under general anesthesia.

Systemic diseases and senile cataract

Senile cataracts have been associated with a lot of systemic illnesses, to include the following: cholelithiasis, allergy, pneumonia, coronary disease and heart insufficiency, hypotension, hypertension, mental retardation, and diabetes.

Systemic hypertension was found to significantly increase the risk for posterior subcapsular cataracts. In a related study by Jahn et al, hypertriglyceridemia, hyperglycemia, and obesity was found to favor the formation of posterior subcapsular cataracts at an early age.[16]

A possible pathway for the role of hypertension and glaucoma in senile cataract formation was proposed with induced changes in the protein conformational structures in the lens capsules, subsequently causing alterations in membrane transport and permeability of ions, and, finally, increasing intraocular pressure resulting in the exacerbation of cataract formation.

UV light and senile cataract

The association of UV light and development of senile cataract has generated much interest. One hypothesis implies that senile cataracts, particularly cortical opacities, may be the result of thermal damage to the lens.

An animal model by Al-Ghadyan and Cotlier documented an increase in the temperature of the posterior chamber and lens of rabbits after exposure to sunlight due to an ambient temperature effect through the cornea and to increased body temperature.[17]

In related studies, people living in areas with greater UV exposure were more likely to develop senile cataracts and to develop them earlier than people residing in places with less UV exposure.

Other risk factors

Significant associations with senile cataract were noted with increasing age, female sex, social class, and myopia. Consistent evidence from the study of West and Valmadrid suggested that the prevalence of all cataract types was lower among those with higher education.[14] Workers exposed to infrared radiation also were found to have a higher incidence of senile cataract development.

Although myopia has been implicated as a risk factor, it was shown that persons with myopia who had worn eyeglasses for at least 20 years underwent cataract extraction at a significantly older age than emmetropes, implying a protective effect of the eyeglasses to solar UV radiation.

The role of nutritional deficiencies in senile cataract has not been proven or established. However, a high intake of the 18-carbon polyunsaturated fatty acids linoleic acid and linolenic acid reportedly may result in an increased risk of developing age-related nuclear opacity.

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Contributor Information and Disclosures
Author

Vicente Victor D Ocampo Jr, MD  Head, Uveitis and Ocular Immunology Service, Veterans Memorial Medical Center, Philippines; Head, Uveitis and Ocular Immunology Service, Ospital ng Makati Medical Center, Philippines; Consulting Staff, Department of Ophthalmology, Asian Hospital and Medical Center, Philippines

Vicente Victor D Ocampo Jr, MD is a member of the following medical societies: American Academy of Ophthalmology, Philippine Academy of Ophthalmology, and Philippine Ocular Inflammation Society

Disclosure: Nothing to disclose.

Coauthor(s)

C Stephen Foster, MD, FACS, FACR, FAAO  Clinical Professor of Ophthalmology, Harvard Medical School; Consulting Staff, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary; Founder and President, Ocular Immunology and Uveitis Foundation, Massachusetts Eye Research and Surgery Institution

C Stephen Foster, MD, FACS, FACR, FAAO is a member of the following medical societies: Alpha Omega Alpha, American Academy of Ophthalmology, American Association of Immunologists, American College of Rheumatology, American College of Surgeons, American Federation for Clinical Research, American Medical Association, American Society for Microbiology, American Uveitis Society, Association for Research in Vision and Ophthalmology, Massachusetts Medical Society, Royal Society of Medicine, and Sigma Xi

Disclosure: Nothing to disclose.

Specialty Editor Board

Richard W Allinson, MD  Associate Professor, Department of Ophthalmology, Texas A&M University Health Science Center; Senior Staff Ophthalmologist, Scott and White Clinic

Richard W Allinson, MD, is a member of the following medical societies: American Academy of Ophthalmology, American Medical Association, and Texas Medical Association

Disclosure: Nothing to disclose.

Simon K Law, MD, PharmD  Associate Professor of Ophthalmology, Jules Stein Eye Institute, University of California, Los Angeles, David Geffen School of Medicine

Simon K Law, MD, PharmD is a member of the following medical societies: American Academy of Ophthalmology, American Glaucoma Society, and Association for Research in Vision and Ophthalmology

Disclosure: Nothing to disclose.

J James Rowsey, MD  Former Director of Corneal Services, St Luke's Cataract and Laser Institute

J James Rowsey, MD is a member of the following medical societies: American Academy of Ophthalmology, American Association for the Advancement of Science, American Medical Association, Association for Research in Vision and Ophthalmology, Florida Medical Association, Pan-American Association of Ophthalmology, Sigma Xi, and Southern Medical Association

Disclosure: Nothing to disclose.

Lance L Brown, OD, MD  Ophthalmologist, Affiliated With Freeman Hospital and St John's Hospital, Regional Eye Center, Joplin, Missouri

Disclosure: Nothing to disclose.

Chief Editor

Hampton Roy Sr, MD  Associate Clinical Professor, Department of Ophthalmology, University of Arkansas for Medical Sciences

Hampton Roy Sr, MD is a member of the following medical societies: American Academy of Ophthalmology, American College of Surgeons, and Pan-American Association of Ophthalmology

Disclosure: Nothing to disclose.

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