From the Guidelines
Cataracts typically present with gradual, painless vision loss, increased glare sensitivity, and decreased contrast sensitivity, ultimately affecting a patient's quality of life and ability to perform daily activities. The clinical findings for cataract (lens opacity) can be diverse, including:
- Gradual, painless vision loss that may manifest as blurry, cloudy, or dim vision
- Increased glare sensitivity, especially when driving at night, and noticing halos around lights
- Decreased color perception, which often becomes dulled or yellowed as the lens opacity progresses
- Decreased contrast sensitivity, making it difficult to distinguish objects against similar backgrounds
- Monocular diplopia (double vision in one eye) due to lens changes
- Temporary improvement in near vision in early stages (second sight phenomenon) as the lens becomes more myopic These findings are supported by the most recent study from 2022, which emphasizes the importance of assessing the impact of cataract on a patient’s visual status and function, as well as the effect on quality of life 1.
The evaluation of visual impairment in cataract patients can be subjectively assessed by self-reported functional status or difficulty with vision, and objectively measured using tests that assess contrast sensitivity, glare disability, or visual acuity at near and distance 1. The Snellen visual acuity chart is an excellent tool for testing distance visual acuity in healthy eyes, but poor preoperative visual acuity correlates with greater postoperative functional improvement in many patients with cataract 1.
It is essential to consider the patient's overall quality of life and ability to perform daily activities when evaluating the clinical findings of cataract, as cataract development can make it difficult for patients to perform basic activities of daily living such as eating and dressing, shopping, personal finances, medication management, and driving 2. The decision to recommend cataract surgery should not be made solely on the basis of Snellen visual acuity, but rather on the patient's overall visual function and quality of life.
The primary indication for cataract surgery is a decline in visual function such that it no longer meets a patient’s visual needs and for which surgery provides a reasonable likelihood of improvement 3. Other indications for cataract removal include clinically significant anisometropia, lens opacity interfering with optimal diagnosis or management of posterior segment pathology, and lens-related glaucoma 3.
The most common types of cataracts are nuclear, cortical, and posterior subcapsular, each with distinct characteristics and effects on visual function 4. Optical testing, including glare testing and contrast sensitivity testing, can help determine the degree of visual impairment and indicate the need for cataract surgery 5.
In summary, the clinical findings for cataract (lens opacity) are diverse and can significantly impact a patient's quality of life and ability to perform daily activities. A comprehensive evaluation of visual impairment and overall quality of life is essential in determining the need for cataract surgery.
From the Research
Clinical Findings for Cataract (Lens Opacity)
The clinical findings for cataract, which is a partial or total opacification of the crystalline lens, can vary depending on the type and location of the opacity. Some common symptoms include:
- Loss of visual acuity 6
- Photophobia 6
- Monocular diplopia 6
- Myopic shift 6
- Change in color vision 6
- Blurred vision 7
- Glare 7
- Knitting the brow 7
- Strabismus 7
- Leukocoria 7
Diagnosis and Classification
Diagnosis of cataract is typically based on slit-lamp examination after pupillary dilation 6. The Lens Opacity Classification System III is currently the gold standard for cataract classification, but its clinical application is limited by its subjective nature 8. Recent advancements in imaging technology, such as Scheimpflug imaging and optical coherence tomography, have opened the possibility of objective assessment of lens structure 8.
Visual Acuity Measurement
Functional visual acuity (FVA) measurement has been reported to be an important method of determining 'masked impairment of visual function' and assessing visual acuity in detail 9. FVA measurement is an effective and noninvasive test that reflects the complaints of blurring/glare and postoperative satisfaction in patients with mild cataract 9. Other methods for predicting visual acuity after cataract surgery include the blue field entoptic test, clinical interferometers, and the Potential Acuity Meter 10.