Keratoconus: Current and Future State-of-the-Art

Preface
Contents
1 Current Advances in Keratoconus Imaging
	1 Introduction
	2 Videokeratoscopy
	3 Scheimpflug Optical Scanning Tomography
		3.1 The Posterior Corneal Surface
		3.2 Corneal Pachymetry Progression
		3.3 Objective Indices to Diagnose Keratoconus Based on Anterior and Posterior Corneal Surfaces
	4 Optical Coherence Tomography
		4.1 Epithelial Maps
		4.2 Posterior Curvature and Aberrations
	5 Wavefront Sensing
	6 Biomechanics
		6.1 The Ocular Response Analyzer
		6.2 The Corvis ST
		6.3 Brillouin Microscopy
	7 Monitoring Keratoconus Progression
	8 Epilogue
	References
2 Tear Film and Ocular Surface in Keratoconus
	1 Introduction
	2 Tear Film- What is Normal?
	3 Ocular Surface and Tear Film in Keratoconus
	4 The Answer is in the Tear Film
	5 MMP Levels in KC
	6 Corneal Innervation in Keratoconus
	7 Floppy Eyelid Syndrome
	8 Managing Keratoconus by Modifying the Ocular Surface
	References
3 The Role of Biomarkers in Keratoconus Pathogenesis and Diagnosis
	1 Introduction
	2 Keratoconus Biomarkers
		2.1 Inflammatory factors
		2.2 ECM-Related Factors
		2.3 Genetic Risk Factors/Markers of Keratoconus
		2.4 Hormones
		2.5 Metabolic and Chemical Alterations
	3 Emerging Perspectives from Biomarker Studies
	4 Conclusion
	References
4 The Potential Roles of Genetic Testing and Biomechanical Evaluation in Keratoconus
	1 Introduction
	2 Genetics of Keratoconus
	3 Genome and Exome Studies
		3.1 Central Corneal Thickness (CCT)
		3.2 Polygenic Risk Scores (PRS)
	4 Biomechanical Properties Determined by Current Clinical Devices, Corneal Hysteresis (CH) and Corneal Resistance Factor (CRF)
		4.1 Gene Expression Linked to Biomechanical Properties
	5 Inflammatory Genes and Immunological Biomarkers Associated with KC
	6 Current and Future Devices to Evaluate the Structural Properties of the Cornea and Its Biomechanics
	7 Clinical Identification of Keratoconus
		7.1 Static Evaluation—Topographic, Tomographic and Pachymetric Assessment
		7.2 Dynamic Evaluation—‘Biomechanical’ Assessment
	8 New Technologies Under Development for Clinical Assessment of Biomechanical Abnormality
		8.1 Techniques Used to Spatially Map the Response of the Cornea to Fluctuations in IOP
		8.2 3-D Assessment Using Brillouin Spectroscopy
	References
5 Crosslinking in Children and Down Syndrome Patients
	1 Epidemiology of Keratoconus in Children
		1.1 Incidence and Prevalence of Keratoconus
		1.2 Impact of Keratoconus on Quality of Life in Children
	2 Diagnostic Challenges in Children and Patients with Down Syndrome
	3 Indication for Crosslinking in Children
		3.1 Prevent a Loss of Visual Acuity
		3.2 Prevent Dependencies of Visual Aids
		3.3 Prevent Surgery
			3.3.1 Indication for Crosslinking in Children Versus Adults
			3.3.2 The Factors That Determine Disease Progression
			3.3.3 The DUtch Crosslinking for Keratoconus (DUCK) Score
	4 Indication for Crosslinking in Down Syndrome
		4.1 Impact of Visual Acuity on QoL in Down Population
		4.2 Late Referrals
		4.3 Lack of Alternatives for Optimal Functioning
		4.4 Diagnostic Challenges
		4.5 Therapeutic Challenges
	5 Therapeutic Challenges in Children and Patients with Down Syndrome
		5.1 In-Office Preparations for Crosslinking in Children
		5.2 Crosslinking Under Local Anesthesia: Choice of Treatment Modality
		5.3 Pain Management in Children
		5.4 Therapeutic Challenges in Down Syndrome
	6 Treatment Efficacy and Long-Term Follow-Up of Pediatric Crosslinking
		6.1 Various CXL Treatment Protocols
			6.1.1 Conventional Versus Modified CXL
		6.2 Topography-Guided CXL
			6.2.1 Long Term Results and Treatment Failure
			6.2.2 Strategies Towards Repeated CXL Treatment
		6.3 Pseudo-Progression Versus Real Progression
	Acknowledgements
	References
6 Accelerated Crosslinking: The New Epithelium-Off
	1 Theoretical Approach and in Vitro Evidence of Efficacy of Accelerated CXL
		1.1 Surgical Procedure
		1.2 Clinical Outcomes
		1.3 Complications and Side Effects of A-CXL
		1.4 Clinical Evaluation of Treatment Success
		1.5 Failure Rates of S-CXL and A-CXL
	References
7 Enhanced Trans-Epithelial Accelerated Crosslinking Protocols: The Way Out of Future CXL
	1 Introduction
	2 Enhanced Fluence Pulsed Light Iontophoresis Protocol (EFPL I-CXL)
		2.1 EFPL I-CXL Surgical Procedure
	3 Enhanced Fluence Pulsed Light M—Trans-Epithelial Crosslinking Protocol (EFPL-M-TECXL)
	4 Customized Trans-Epithelial Corneal Crosslinking with Supplemental Oxygen
	References
8 Corneal Cross-Linking at the Slit Lamp
	1 Bringing Surgical Procedures Out of the OR
	2 CXL ‘sterilizes’ the Cornea
	3 Adapting CXL for Keratoconus to the Slit Lamp
	4 Summary
	References
9 Corneal Cross-Linking in Ultrathin Corneas
	References
10 Corneal Allogenic Intrastromal Ring Segments C.A.I.R.S
	1 Introduction
	2 Classification of ICRS
	3 History
	4 Conclusion
	References
11 All Surface Laser Ablation and Crosslinking
	1 All Surface Laser Ablation
	2 Customized Treatments: The STARE-X Protocol for Corneal Regularization
	3 All Surface Laser Ablation with Cross-Linking (ASLA-XTRA) for the Treatment of Myopia
	References
12 IOL’S For Visual Rehabilitation in Stable Keratocounus
	1 Criteria of a Stable Keratoconus
		1.1 Duration of Stability Evaluation
		1.2 Corneal Biomechanics
		1.3 Epithelial Thickness
		1.4 Corneal Hysteresis
			1.4.1 Refraction
			1.4.2 Visual Acuity
	2 ICL in Keratoconus Patients
		2.1 The Choice of ICL
		2.2 How to Refract
		2.3 How to Measure ICL
			2.3.1 Novel Technologies for More Accurate WTW Measurement
	3 Cataract Surgery in Keratoconus Patients
		3.1 IOL Selection
		3.2 IOL Power Calculation
		3.3 Incision
		3.4 Particularities of Phacoemulsification
		3.5 Post Operative Considerations
		3.6 Innovations in IOLs Technology
	References
13 Femtosecond-Laser Assisted Deep Anterior Lamellar Keratoplasty (F-DALK)
	References
14 SLAK: Stromal Lanticule Addition Keratoplasty
	1 SLAK: Background and Rationale
	2 Surgical Technique
		2.1 Lenticule Preparation
		2.2 Lenticule Implantation Technique
	3 SLAK Results
		3.1 Ex-vivo Morphological Results
		3.2 Clinical Results in Humans
		3.3 In Vivo Confocal Microscopy Morphological Outcomes
	4 Future of SLAK
	References
15 Donor-Recipient Crosslinking-Assisted Manual Deep Anterior Lamellar Keratoplasty: DRXL-DALK
	1 Introduction
	2 Our DRXL-DALK Technique
	3 Repairing Descemet’s Ruptures
	4 Corneal Cross-Linking (CXL) as Adjuvant Treatment in DALK Surgery
	References
Index