Introduction
Certain long-term medications, such as Hydroxychloroquine, Tamoxifen, and Letrozole, are essential for managing conditions like autoimmune diseases and breast cancer. However, prolonged use of these drugs can pose risks to retinal health, potentially leading to irreversible vision loss if not monitored effectively.
At The Retina Clinic London, we provide the most advanced drug toxicity screening services available, allowing for early detection and precise monitoring of retinal changes. Our comprehensive approach, led by Professor Paulo Stanga and his expert team, combines cutting-edge imaging, functional vision tests, and personalised follow-up care to protect your vision while you continue your essential treatments.
Why Drug Toxicity Screening is Essential
Some medications accumulate in the retina over time, leading to progressive toxicity. Without routine screening, vision loss may go unnoticed until irreversible damage occurs.
At The Retina Clinic London, we ensure:
Early Detection: We use state-of-the-art diagnostic tools to detect the earliest signs of retinal toxicity, often before symptoms appear.
Personalised Risk Assessments: Screening schedules are tailored to each patient’s medication history, dosage, and individual risk factors.
Comprehensive Monitoring: Our advanced imaging and functional testing help track subtle changes in retinal structure and function over time.
Medications We Monitor & Associated Retinal Risks
1. Hydroxychloroquine Retinopathy
What is it?
Hydroxychloroquine, commonly prescribed for lupus and rheumatoid arthritis, can accumulate in the retinal pigment epithelium (RPE) and photoreceptor layers, leading to permanent vision loss if undetected.
Risk Factors for Toxicity:
- Use beyond five years
- Higher cumulative dosage (>5g total exposure)
- Reduced kidney or liver function
- Pre-existing retinal conditions
Symptoms of Toxicity:
- Blurred or patchy central vision
- Difficulty reading
- Loss of colour vision
- Bull’s Eye Maculopathy (a characteristic ring of damage on imaging)
2. Tamoxifen Retinopathy
What is it?
Tamoxifen is a hormonal therapy for hormone-receptor-positive breast cancer. Long-term exposure can cause crystalline deposits in the macula, leading to progressive vision impairment.
Risk Factors for Toxicity:
- Use beyond five years
- Higher cumulative dosage
- Pre-existing retinal conditions
Symptoms of Toxicity:
- Blurred or distorted central vision
- Difficulty reading or recognising faces
- Changes in colour perception
- Sensitivity to light
3. Letrozole & Retinal Toxicity
What is it?
Letrozole is an aromatase inhibitor used in postmenopausal breast cancer treatment. While less frequently associated with retinal toxicity, long-term use may disrupt retinal blood flow, leading to vascular changes.
Risk Factors for Toxicity:
- Long-term therapy
- Pre-existing vascular or retinal conditions
Symptoms of Toxicity:
- Blurred or hazy vision
- Increased difficulty in low light
- Subtle distortions in visual perception
Our Comprehensive Screening Approach
At The Retina Clinic London, we use a multimodal diagnostic approach, combining advanced imaging and functional vision tests to assess retinal health at the earliest stages of toxicity.
State-of-the-Art Diagnostic Tests:
1. High-Resolution Optical Coherence Tomography (OCT) & Ultra-Widefield OCT
Provides detailed cross-sectional imaging of the retina and macula
Essential for detecting early Hydroxychloroquine toxicity
Identifies macular oedema and crystalline deposits from Tamoxifen
2. Fundus Autofluorescence (FAF)
Detects early metabolic stress in the retina, often before structural damage occurs
Identifies bull’s eye maculopathy in Hydroxychloroquine toxicity
Monitors Tamoxifen-induced retinal changes
3. Visual Field Testing (Static Perimetry)
Assesses loss of sensitivity in central and peripheral vision
Detects functional deficits before structural changes are visible
4. Multifocal Electroretinography (mfERG)
Measures photoreceptor function across different retinal regions
Highly sensitive for detecting early Hydroxychloroquine toxicity
5. Microperimetry
Precisely maps retinal sensitivity, showing how vision is affected at different locations
Helps identify subtle visual changes that may not appear in standard tests
6. Adaptive Optics Imaging
Provides cellular-level imaging of individual photoreceptors
Detects microscopic damage from toxicity before vision is impacted
7. Colour Vision Testing
Identifies early colour perception changes, which are often an early sign of toxicity
8. Ultra-Widefield Fundus Imaging
Documents retinal structure and crystalline deposits for long-term monitoring
Recommended Screening Timelines
We follow the latest international guidelines to ensure regular and effective monitoring:
Hydroxychloroquine: Baseline screening within the first year of use, then annual screenings after five years (earlier for high-risk patients).
Tamoxifen: Baseline screening, then annual follow-ups after five years (or sooner if symptoms develop).
Letrozole: Baseline assessment within the first year, with follow-up based on individual risk factors.
For high-risk patients (pre-existing retinal conditions, high cumulative drug exposure, or impaired kidney/liver function), more frequent monitoring may be required.
Why Choose The Retina Clinic London?
At The Retina Clinic London, we provide the most comprehensive drug toxicity screening service available, ensuring early detection, precise monitoring, and expert-led management.
Led by World-Renowned Experts. Professor Paulo Stanga and his team are leaders in retinal disease management and drug toxicity monitoring.
The Most Advanced Imaging Technology. We use ultra-high-resolution OCT, microperimetry, adaptive optics, and AI-assisted analysis to detect early toxicity changes.
Personalised Screening Plans. Each patient’s screening frequency and follow-up schedule is tailored to their specific medication history and risk factors.
Comprehensive Reporting. We provide detailed reports for patients and referring physicians, ensuring seamless care integration.
What to Expect from Your Screening at The Retina Clinic London
Initial Consultation. Discussion of your medication history, health status, and any visual symptoms.
Advanced Retinal Imaging & Functional Testing. Non-invasive tests to detect any early changes in retinal structure and function.
Expert Review. Professor Stanga and his team personally analyse all imaging and test results.
Personalised Recommendations. Tailored follow-up screening and management plan based on your individual risk level and test findings.
Book Your Drug Toxicity Screening
If you are taking Hydroxychloroquine, Tamoxifen, or Letrozole, regular screening is essential to safeguard your vision.
Call us today on: +44 (0)20 4548 5310
Email us at: info@theretinacliniclondon.com
At The Retina Clinic London, your eye health is our priority. Schedule your comprehensive drug toxicity screening and ensure early detection, precise monitoring, and expert care for your vision.