The Foundation of Every Contact Lens Fit
A thorough patient history is the first and arguably most important step in the contact lens fitting process. Before any measurements are taken or lenses are tried, you need to understand who the patient is, what they need, and whether contact lenses are appropriate for them. The history guides every subsequent decision, from lens type selection to wearing schedule recommendations.
Key History Components
Occupation and Work Environment
Understanding the patient's occupation helps you select the right lens type and wearing schedule:
- Computer and office work: Extended screen time reduces blink rate, increasing dryness. Consider lenses with high moisture retention and recommend scheduled blinking breaks
- Dusty or industrial environments: Particles can get trapped under lenses. Daily disposables may be preferred to avoid deposit buildup. Safety eyewear requirements may also apply
- Healthcare workers: Frequent handwashing and potential chemical exposure. Good lens hygiene awareness is typically high in this group
- Outdoor occupations: Wind and UV exposure. Consider UV-blocking lens materials
- Shift workers: Irregular schedules may affect wearing time and sleep patterns, impacting corneal recovery
Hobbies and Activities
Recreational activities significantly influence lens selection:
- Sports: Contact lenses provide better peripheral vision than spectacles. Daily disposables work well for occasional sport use. Contact sports may benefit from soft over rigid lenses due to dislodgement risk
- Swimming: Lenses should not be worn in water without protective goggles due to infection risk (particularly Acanthamoeba). If worn, daily disposables discarded immediately after are the safest option
- Water sports: Similar concerns to swimming, with added UV exposure considerations
Motivation
Understanding why the patient wants contact lenses helps set appropriate expectations:
- Cosmetic: Wants to avoid wearing glasses for appearance. May be less tolerant of discomfort if motivation is purely cosmetic
- Sports and activities: Functional motivation, often very committed to making lenses work
- Convenience: Dislikes the hassle of glasses. May prefer the simplicity of daily disposables
- Vision quality: Some prescriptions (high myopia, anisometropia) provide better vision with contact lenses than spectacles
A patient who wants contacts primarily for a single activity (such as weekend sports) may be best served by daily disposable lenses for part-time wear, while a patient who wants full-time correction needs a lens and modality suited for extended daily wearing hours.
Medical and Ocular History
Systemic Conditions
Several systemic conditions can affect contact lens success:
- Diabetes: Can reduce corneal sensitivity, delay epithelial healing, and increase infection risk
- Autoimmune diseases (rheumatoid arthritis, lupus, Sjogren's syndrome): Often associated with dry eye, making lens wear more challenging
- Thyroid disease: May affect lid position and tear film quality
- Pregnancy: Hormonal changes can alter corneal curvature and tear production. Refraction may be unstable
Medications
Certain medications can significantly impact contact lens comfort and safety:
- Antihistamines: Reduce tear production, causing dryness
- Oral contraceptives: May affect tear film quality and quantity
- Beta-blockers: Can reduce tear secretion
- Isotretinoin (Accutane): Severely reduces meibomian gland secretion, often making contact lens wear intolerable
- Diuretics: Can cause systemic dehydration affecting tear volume
- Antidepressants (tricyclic): Have anticholinergic effects that reduce tear production
When a patient reports taking multiple medications that affect tear production (such as antihistamines plus an antidepressant), the cumulative effect on the tear film is often greater than either medication alone. These patients are at higher risk for contact lens-related dryness and may benefit from daily disposable lenses, rewetting drops, or supplemental artificial tears.
Contraindications to Contact Lens Wear
Absolute contraindications (contact lenses should not be fitted):
- Active eye infection (bacterial, viral, or fungal keratitis)
- Severe, uncontrolled dry eye that does not respond to treatment
- Inability to handle or care for lenses (due to dexterity limitations, cognitive issues, or lack of motivation for hygiene)
- Active corneal disease that would be worsened by lens wear
Relative contraindications (proceed with caution and careful monitoring):
- Chronic allergies with significant papillary response
- Mild to moderate dry eye (may be managed with lens type selection and supplemental tears)
- Recurrent corneal erosion (lens may help in some cases, worsen in others)
- Environmental factors (extremely dusty or chemical-laden workplaces)
- Medications that reduce tear production
Failing to ask about medication use during the contact lens history. Many systemic medications reduce tear production or quality, and patients may not think to mention them unless specifically asked. Always include a thorough medication review in your prefitting history.
Previous Contact Lens Experience
For patients who have worn contact lenses previously, gather details about:
- Lens type, brand, and parameters previously worn
- Wearing schedule (daily wear vs. extended wear, hours per day)
- Care system used and compliance level
- Reasons for discontinuation or desire to change
- Any previous complications (infections, discomfort, dry eye)
This information helps you avoid repeating unsuccessful approaches and build on what has worked well in the past.
Key Takeaways
- Patient history should cover occupation, hobbies, motivation, medical history, medications, and previous lens experience
- Antihistamines, oral contraceptives, beta-blockers, and isotretinoin are common medications that affect tear film
- Active infections, severe dry eye, and inability to maintain hygiene are absolute contraindications
- Patient motivation and lifestyle drive lens type and modality selection
- Previous contact lens experience provides valuable guidance for current fitting decisions
- Multiple drying medications have a cumulative negative effect on tear production