Clinical Presentation and Treatment of Cataracts
Clinical Presentation
Cataracts present with painless, progressive blurring of vision and visual glare, with symptoms varying by anatomical type and location of lens opacity. 1
Core Visual Symptoms
- Decreased visual acuity at distance and/or near that fails to improve with refraction is the hallmark symptom 2
- Visual glare, particularly problematic in bright lighting conditions or while driving at night, especially with cortical and posterior subcapsular cataracts 3, 2
- Reduced contrast sensitivity affecting daily activities like reading, recognizing faces, and navigating stairs 3, 2
- Monocular diplopia or ghosting from impaired optical quality 3
- Halos and starbursts at night, particularly affecting nighttime driving 3
Cataract Type-Specific Presentations
- Nuclear cataracts cause central lens opacification with slow progression, affecting distance vision more than near vision, and may cause a myopic shift 2
- Cortical cataracts appear as opaque spokes or oil droplets and commonly produce severe glare symptoms 2
- Posterior subcapsular cataracts (PSCs) located just inside the posterior lens capsule cause substantial visual impairment with glare and poor vision in bright light, affecting near vision more than distance 2
Functional Impact Assessment
Visual acuity testing alone significantly underestimates the functional problems experienced by patients in real-life situations. 3 The comprehensive evaluation must include:
- Distance and near visual acuity with current correction documented 3
- Glare testing to reveal functional disability greater than Snellen acuity alone suggests, particularly useful as cataracts may cause severe disability in bright conditions while showing normal acuity in darkened exam rooms 3, 2
- Contrast sensitivity testing to demonstrate loss of visual function not appreciated by Snellen testing alone 3, 2
- Patient-reported outcome measures (PROMs) using vision-specific questionnaires like VF-14, NEI-VFQ, or Catquest-9SF, which correlate more strongly with postoperative improvement than general health measures 3
Diagnostic Examination Components
The comprehensive ophthalmic evaluation must include 3:
- Patient history assessing functional status, pertinent medical conditions (diabetes, immunosuppressive conditions), and medications (systemic alpha-1 antagonists like tamsulosin) that affect surgical planning 3
- Refraction and corrected distance visual acuity in both eyes 3
- Pupil size and function assessment 3
- Slit-lamp biomicroscopy of cornea, anterior chamber, iris, lens, vitreous, macula, peripheral retina, and optic nerve through dilated pupil to classify opacities by anatomical distribution 3
- Indirect ophthalmoscopy to identify comorbid retinal pathology that may limit postoperative visual potential 3
Critical Diagnostic Pitfall
Always rule out other causes of vision loss before attributing symptoms solely to cataracts. 2 Patients may present with visual symptoms disproportionate to the degree of cataract formation, requiring correlation between slit-lamp findings and specific symptoms to establish cataract as the primary etiology 3.
Treatment
Surgery to remove the cataract and implant a permanent intraocular lens is indicated when visual impairment from cataracts affects activities of daily living despite optimal correction. 2, 1
Surgical Indications
The decision to recommend cataract surgery should not be made solely on the basis of Snellen visual acuity. 3 Surgery is indicated when:
- Visual function decline no longer meets the patient's visual needs and surgery provides reasonable likelihood of improvement 2
- Functional impairment affects activities of daily living including eating, dressing, shopping, personal finances, medication management, reading, fine handiwork, poor night vision, and difficulty recognizing people 3, 2
- Safety concerns arise from night vision difficulties and glare symptoms increasing fall and accident risk 2
Surgical Technique and Outcomes
- Phacoemulsification with intraocular lens (IOL) implantation is the standard of care and produces excellent outcomes 2, 4
- Most procedures use topical anesthesia, eliminating the need for preoperative general medical testing such as bloodwork or electrocardiogram 1
- Patients do not need to discontinue anticoagulants for cataract surgery 1
- Systemic α1-adrenergic antagonists (tamsulosin for benign prostatic hyperplasia) increase surgical complication risk; some ophthalmologists temporarily discontinue preoperatively 1
- Intraocular antibiotics (moxifloxacin or cefuroxime) delivered intraoperatively have reduced sight-threatening postsurgical endophthalmitis rates from 0.07% to 0.02% 1
Expected Benefits
Cataract surgery provides substantial improvements in 3:
- Improved distance-corrected visual acuity 3
- Increased ability to read or do near work 3
- Reduced glare 3
- Improved ability to function in dim light 3
- Improved depth perception and binocular vision by eliminating anisometropia 3
- Improved color vision 3
- Improved peripheral vision 3
Quality of Life and Safety Outcomes
Cataract surgery is associated with lower rates of falls (>30%) and dementia (20%-30%), with patients less likely to be in serious car crashes as the driver. 3, 1 The surgery enhances:
- Physical function, mental health, and emotional well-being 3
- Cognitive abilities in the very elderly 3
- Driving performance during day and night 3
- Self-care activities 3
Advanced Technology Options
Advanced technology IOL designs, such as multifocal IOLs, can reduce dependence on eyeglasses but are associated with increased costs not covered by medical insurance. 1 These optional refractive benefits should be discussed with patients seeking reduced spectacle dependence 1.
Postoperative Expectations
The majority of very elderly patients live at least 1 year following surgery, and many live much longer, with poor preoperative visual acuity correlating with greater postoperative functional improvement. 3 Up to 90% of patients note improvement in functional status following surgery 5.