Navigating Keratoconus: A Comprehensive Guide for Optometrists
Keratoconus is a challenging condition that demands careful management and a nuanced understanding of its progression and treatment. This article, written by Professor Stephanie Watson and Himal Kandel, offers a comprehensive guide for optometrists, synthesizing clinical trial evidence, registry data, and consensus guidance. It aims to empower optometrists in effectively managing patients with keratoconus, focusing on early detection, progression management, visual rehabilitation, and long-term care.
Early Detection and Diagnosis
Recognizing keratoconus early is crucial. The condition is relatively common, with a global prevalence of 8.16 per 1,000 people and affecting one in 84 Australians aged 20. It often begins in childhood or young adulthood, making a high index of suspicion essential. Key signs include blurred or distorted vision, increased light sensitivity, and frequent refractive changes, particularly progressive astigmatism.
Risk factors include eye rubbing, atopy, family history, consanguinity, and conditions like trisomy 21 (Down's syndrome). Subjective refraction, noting pinhole vision compared to spectacle refraction, and astigmatism measurement (more than 2D) are crucial for diagnosis. Corneal imaging, using modern tomographers like Pentacam and Galilei, confirms the diagnosis.
Progression Management and Corneal Cross-Linking (CXL)
Steeper Kmax and younger age are significant predictors of keratoconus progression. Patients with Kmax >55D and younger than 21 years are at higher risk. Short waitlists for CXL are essential due to the potential for rapid progression.
CXL is the gold standard treatment for progressive keratoconus or high-risk patients. Its efficacy and safety in preventing progression and improving vision are well-established in clinical trials. Early referral is crucial, especially for younger patients, those with family history, and those showing progression.
Visual Rehabilitation
Visual rehabilitation aims to restore functional vision tailored to the patient's needs, not necessarily achieving 6/6 vision. Early keratoconus patients may manage with unaided vision, spectacle correction, or contact lenses. Soft contact lenses are suitable for functional vision, while hard contact lenses are necessary for irregular astigmatism.
Surgical Options and Long-Term Management
Corneal grafting, deep anterior lamellar keratoplasty (DALK), and various surgical options like laser, phakic intraocular lenses, and intrastromal ring segments are available. CXL can be performed before, during, or after these procedures.
Long-term management involves close follow-up, especially in children and adolescents, with intervals determined by progression risk. Eye rubbing increases progression risk, necessitating frequent monitoring.
Tracking and Benchmarking Outcomes
The Save Sight Keratoconus Registry is a valuable tool for tracking patient outcomes, benchmarking practices against national and international standards, and sharing data between ophthalmologists and optometrists. It facilitates accreditation for CPD requirements and contributes to research publications.
Patient-Reported Outcomes
The Keratoconus Outcomes Research Questionnaire (KORQ) captures patient-reported outcomes, providing valuable insights into the multifaceted impact of keratoconus on quality of life. This data complements clinical assessments, offering a comprehensive understanding of patient functioning and treatment benefits.
Conclusion
Managing keratoconus is rewarding, offering clinicians a range of treatment options to prevent progression and improve quality of life. The Save Sight Keratoconus Registry encourages real-world evidence collection, driving improvements in care through benchmarking and research. By embracing these comprehensive guidelines, optometrists can provide exceptional care to patients with keratoconus.
