Pediatric Cataract: For Every Ophthalmologist

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