Pediatric Cataract: For Every Ophthalmologist

Description

The book covers all clinical aspects of pediatric cataract surgery. Chapters cover basic sciences, etiology, pre-operative evaluation, choice of intraocular lenses, steps of surgery, complications, considerations in traumatic cataract and post-operative rehabilitation. It includes photographs, diagrams, flow charts and tables for easy memorization and understanding. Multiple choice questions at the end of each chapter help to evaluate the understanding and reinforce important concepts. The book aims to encourage ophthalmic surgeons to successfully treat children with cataract as all of them perform adult cataract surgeries but usually avoid managing pediatric cases. This hesitation is primarily due to exhaustive pre-operative evaluation and long term follow up. As a result the back log of this disease in the developing world is significant and many such children are unable to receive timely intervention during their crucial period of visual development. The chapters primarily focus on the clinically relevant issues to keep the reader interested. The book includes contributions from some of the most talented and experienced pediatric cataract surgeons. The book is relevant for ophthalmologists not commonly practicing pediatric cataract surgery and post graduate students. Foreword Preface Notice Contents Editor and Contributors About the Editor Contributors 1: The Pediatric Eye 1.1 Introduction 1.2 The Developing Eye 1.3 The Intra-uterine Phase 1.3.1 Formation of the Germ Layers 1.3.2 Formation of Neural Tube 1.3.3 Formation of the Eye 1.3.4 Development and Differentiation of Ocular Structures 1.3.4.1 Cornea and Anterior Chamber 1.3.4.2 Crystalline Lens 1.3.4.3 Uvea and Sclera 1.3.4.4 Trabecular Meshwork 1.3.4.5 Retina and Vitreous 1.3.4.6 Optic Nerve 1.3.4.7 Intra-ocular Blood Supply 1.4 The Phases of Postnatal Growth, Emmetropization and Visual Maturation 1.4.1 Ocular Dimensions 1.4.2 Orbit 1.4.3 Extra-Ocular Muscles and Movements 1.4.4 Cornea 1.4.5 Sclera 1.4.6 Iris and Pupil 1.4.7 Anterior Chamber 1.4.8 Intra-ocular Pressure 1.4.9 Crystalline Lens 1.4.10 Retina 1.5 Visual Functions 1.5.1 Visual Acuity 1.5.2 Colour Vision and Contrast Sensitivity 1.5.3 Depth Perception 1.6 Emmetropization 1.7 Development of Binocular Single Vision 1.8 Amblyopia 1.9 Congenital Abnormalities 1.10 Summary References 2: Etiology of Pediatric Cataract 2.1 Introduction 2.2 Epidemiology 2.3 Pathophysiology 2.4 Genetics 2.5 Etiology 2.5.1 Idiopathic 2.5.2 Maternal Infections 2.5.3 Metabolic and Systemic Disorders 2.5.4 Ocular Malformations 2.5.5 Chromosomal Abnormalities 2.5.6 Isolated Hereditary (Familial) Cataract 2.5.7 Traumatic Cataract 2.5.8 Secondary and Iatrogenic Cataracts 2.5.9 Cataract in Prematurity 2.6 Abnormalities in Structure and Position of the Crystalline Lens 2.6.1 Structural Abnormalities 2.6.2 Positional Anomalies 2.7 Summary References 3: Preoperative Evaluation of Pediatric Cataract 3.1 Introduction 3.2 History 3.3 Examination 3.3.1 Vision Assessment in Children 3.3.2 Ocular Movements 3.3.3 Oculo-digital Phenomenon 3.3.4 Pupils 3.3.5 Red Reflex Test 3.3.6 Anterior Segment Examination 3.3.7 Lens Examination 3.3.8 Posterior Segment Examination 3.4 Syndromic Associations 3.5 Investigations 3.6 Surgical Planning 3.7 Parent Counselling 3.8 Summary References 4: Intraocular Lenses in Pediatric Patients 4.1 Introduction 4.2 Challenges in IOL Implantation in Children 4.3 Selecting the Appropriate Patient 4.3.1 IOL Implantation in Unilateral Developmental Cataract 4.3.2 IOL Implantation in Bilateral Developmental Cataracts 4.4 IOL Power Determination in Pediatric Eyes 4.4.1 Biometry 4.4.2 Target Postoperative Refraction 4.5 IOL Material, Type, and Size 4.6 Additional Tips for IOL Implantation in Pediatric Cataract Surgery 4.6.1 Preferred Site of IOL Implantation 4.6.2 Optic Capture of IOL 4.6.3 Toric and Multifocal IOLs 4.6.4 Secondary IOL Implantation 4.7 Summary References 5: Pediatric Cataract Surgery 5.1 Introduction 5.2 Challenges with Pediatric Cataract Surgery 5.2.1 Need for General Anaesthesia 5.2.2 Decreased Scleral Rigidity 5.2.3 Lesser Space in Anterior Chamber and Capsular Bag 5.2.4 Capsular Elasticity 5.2.5 Anterior Chamber Instability 5.2.6 Lens Aspiration Only 5.2.7 Increased Inflammation 5.2.8 The Growing Globe 5.2.9 Visual Axis Opacification 5.3 Preoperative Planning 5.3.1 When to Operate? 5.3.2 Informed Consent 5.3.3 Intraocular Lens 5.3.4 Surgical Options 5.4 Preoperative Preparation 5.5 General Anaesthesia 5.5.1 Preoperative Assessment 5.5.2 Special Considerations in Pediatric Patients 5.5.3 Examination Under Anaesthesia 5.6 Surgical Steps 5.6.1 Instrumentation and Draping 5.6.2 Incisions 5.6.3 Anterior Capsulorhexis 5.6.4 Hydrodissection and Lens Aspiration 5.6.5 Posterior Capsule Management 5.6.6 Anterior Vitrectomy 5.6.7 Pars Plana Vitrectomy with Lensectomy 5.6.8 IOL Implantation 5.6.9 Optic Capture 5.6.10 Viscoelastic Aspiration, Peripheral Iridectomy and Incision Closure 5.6.11 Subconjunctival/Subtenon Injections 5.6.12 Post-operative Medications 5.7 Common Per-operative Complications and Their Management 5.8 Considerations in Concurrent Ocular Comorbidities 5.8.1 Microphthalmos 5.8.2 Lenticonus 5.8.3 Lens Coloboma/Subluxated and Dislocated Cataract 5.8.4 Buphthalmos 5.8.5 Persistent Fetal Vasculature 5.8.6 Uveitis 5.9 Prognosis 5.10 Summary Annexure 1: Consent for Pediatric Cataract Surgery A.1 Introduction A.2 Post-operative Care A.3 Post-operative Course and Possible Complications A.4 Patient Consent (to Be Signed by Legal Guardian in Children) Annexure 2: Checklist for Receiving a Pediatric Cataract Patient in the Operating Room References 6: Pediatric Cataract Surgery: Post-operative Complications and Their Management 6.1 Introduction 6.2 Early Post-operative Complications (within 4 weeks of surgery) 6.2.1 Inflammation 6.2.1.1 Prevention: Pre-operative 6.2.1.2 Prevention: Intraoperative 6.2.1.3 Prevention: Post-operative 6.2.1.4 Management of Fibrinous Membranes 6.2.1.5 Toxic Anterior Segment Syndrome (TASS) 6.2.2 Endophthalmitis 6.2.3 Wound-Related Problems 6.2.4 IOL-Related Complications 6.2.5 Post-operative IOP Spike and Early-Onset Glaucoma 6.3 Late Post-operative Complications (after 4 weeks of surgery) 6.3.1 Visual Axis Opacification 6.3.1.1 Prevention 6.3.1.2 Management Neodymium-YAG Laser Capsulotomy Secondary Surgical Membranectomy 6.3.2 Refractive Error 6.3.2.1 Contact Lens and Spectacles for Aphakia 6.3.2.2 Primary IOL Implantation 6.3.2.3 Secondary IOL Implantation 6.3.2.4 Involving the Parents in Decision-Making 6.3.2.5 Refractive Surprise and Myopic Shift Myopic Shift Optimal Target Refraction for Primary IOL Implantation Management 6.3.2.6 Loss of Accommodation 6.3.3 Corneal Complications 6.3.3.1 Surgically Induced Astigmatism 6.3.3.2 Corneal Endothelial Cell Loss and Decompensation 6.3.4 Retinal Detachment 6.3.5 Glaucoma 6.3.5.1 Is Insertion of an IOL Protective? 6.3.5.2 Monitoring and Diagnosis 6.3.5.3 Treatment 6.4 Summary References 7: Considerations in Traumatic Cataract in Children 7.1 Introduction 7.2 Epidemiology and Significance of Traumatic Cataract in Children 7.3 Classification of Ocular Trauma 7.3.1 Closed Globe Trauma 7.3.2 Open Globe Trauma 7.4 Traumatic Cataract 7.5 Clinical Evaluation 7.5.1 History of Injury 7.5.2 Examination 7.6 Investigations 7.7 Preoperative Counselling 7.8 Surgical Decision-Making 7.8.1 Optical Correction 7.8.2 Timing of Surgery 7.8.3 Choice of Anaesthesia 7.8.4 Incision and Tunnel 7.8.5 Synechiolysis 7.8.6 Pupil Expansion Devices 7.8.7 Repair of Iris and Pupil 7.8.8 Anterior Capsule Management 7.8.9 Hydro Procedures 7.8.10 Nucleus Management 7.8.11 Posterior Capsule 7.8.12 Vitrectomy 7.8.13 Placement and Choice of Intraocular Lens 7.9 Complications 7.9.1 Endophthalmitis 7.9.2 Visual Axis Opacification 7.9.3 IOL Capture and Decentration 7.9.4 Amblyopia 7.10 Follow-Up Examinations 7.11 Prognosis 7.12 Summary References 8: Post-operative Rehabilitation After Cataract Surgery in Children 8.1 Introduction 8.2 Post-operative Follow-Ups 8.3 Optical Rehabilitation 8.3.1 Visual Acuity Assessment and Refraction 8.3.2 Optical Correction 8.3.2.1 Pseudophakic Children 8.3.2.2 Aphakic Children 8.4 Visual Axis Opacification 8.5 Anisometropia 8.6 Amblyopia 8.7 Comorbid Conditions 8.8 Considering Refractive Procedures 8.9 Parent and Child Counselling 8.10 Low Vision Rehabilitation 8.11 Summary References