Pediatric Cataract Surgery Suresh K Pandey, Frank A Billson, Elie Dahan, Howard V Gimbel
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1Step by Step: Pediatric Cataract Surgery
2Step by Step: Pediatric Cataract Surgery
Editors Suresh K Pandey MD • Achievement Awardee American Academy of Ophthalmology (2003) • Intraocular Implant Unit Sydney Hospital & Sydney Eye Hospital Macquarie St, Sydney 2001, Australia • Scholar of the University of Sydney Save Sight Institute and Discipline of Ophthalmology, Sydney, NSW, Australia 2001 • Assistant Professor John A. Moran Eye Center Department of Ophthalmology & Visual Sciences University of Utah, 50 North Medical Drive Salt Lake City, Utah-84132, USA • Formerly Postdoctoral Fellow Department of Ophthalmology Albert Florens Storm Eye Institute Medical University of South Carolina Charleston, SC-29425, USA Frank A Billson AO, FRANZCO, FRACS, FRCS (Lon), FRCOphth, FACS Founding Professor of Ophthalmology Founding Director Save Sight Institute Centre for Ophthalmology and Visual Sciences Head of Discipline of Ophthalmology University of Sydney Campus of Sydney Hospital & Sydney Eye Hospital 8 Maquarie Street Sydney, Australia Special Contributing Editors Elie Dahan MD MMed Ophth Professor of Ophthalmology Director- Oxford Eye Center University of the Witwatersrand Johannesburg South Africa Howard V Gimbel MD, MPH, FRCSC, FACS Director, Gimbel Eye Centre Calgary, Alberta, Canada Professor and Chairman Department of Ophthalmology Loma Linda University, Loma Linda, California Clinical Professor, Department of Ophthalmology University of California, San Francisco, USA
3Published by
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Step by Step Pediatric Cataract Surgery
© 2005, Editors
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This book has been published in good faith that the material provided by contributors is original. Every effort is made to ensure accuracy of material, but the publisher, printer and editors will not be held responsible for any inadvertent error(s). In case of any dispute, all legal matters are to be settled under Delhi jurisdiction only.
First Edition: 2005
9788180614477
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4
5Foreword
The contributions in this multi-authored handbook are in the mainstream of current thinking in pediatric cataract surgery and intraocular lens implantation. The Editors Suresh K. Pandey and Frank A. Billson have succeeded in bringing together different viewpoints to produce a text of even consistency focussed through the recognition of common underlying principles. The addition of key references exceeds the usual expectation one has for a book of this nature. The opinions expressed in this book reflect the different backgrounds of the authors highlighted by the differences of those coming from a major background in adult cataract surgery as opposed to those whose practice is predominantly in the pediatric age group. Those involved with a particular interest in intraocular lens design add a further dimension to the quality of the discourse. What emerges is clear agreement of the principles of cataract surgery and the place of intraocular lens implantation in the pediatric age group, particularly after the age of two.
Where opinions are most divided is in the first two years of life with increasing divergence about intraocular lens implantation in early infancy perhaps being greatest at birth. This is not unexpected as this is the period of the 6most rapid change in ocular and visual development with dramatic alterations in anatomical structure during the most crucial and vulnerable period of the maturing visual system. The infant as an organism is evolving with particular structural changes in the cardio-pulmonary system and sensitivities of the hypothalamus and autonomic nervous system to associated reflexes creating special problems that emphasize the need for specialized training and interest in pediatric anesthesia. Problems inherent in operating in very early infancy are highlighted by the contrast between the resources available for managing pediatric cataract in developed countries as opposed to those in developing countries where not only is there limitation in human and material resources but have the added problem of late presentation from communities whose expectations are less than those in the developed world.
The book will be useful not only for ophthalmologists in training but also for general ophthalmologists, pediatricians and health professionals who seek to keep touch with the latest thinking in respect to management of pediatric cataract and intraocular lens implantation in early childhood. Drs Pandey and Billson, and all contributors are to be congratulated for bringing out well-focussed and timely book that will be welcomed not only for its contents but also for its size that fits easily into a coat pocket.
Creig S Hoyt md
Theresa M and Wayne M Caygill, MD, Endowed Chair
Professor and Chairman
Department of Ophthalmology
University of California, San Francisco, CA, USA
Editor-in-Chief, British Journal of Ophthalmology
7Preface
This handbook on Pediatric Cataract Surgery includes total of 14 chapters contributed by 28 different authors. The views expressed in this book reflect the different backgrounds of the authors highlighted by the differences of those coming from a major background of pediatric ophthalmology and cataract surgery in the pediatric age group as opposed to those whose practice is predominantly in adult cataract surgery with an interest in surgical management of pediatric cataract. The practical aspect of the removal of the lens and intraocular lens insertion is shared equally between the pediatric ophthalmologists and adult cataract surgeon with interest in pediatric cataracts. Those involved with a particular interest in intraocular lens design add a further dimension to the quality of the contribution. What emerges is clear agreement of the principles of cataract surgery and the place of intraocular lens implantation in the pediatric age group, particularly after the age of two.
The art of medicine does not always lie in single answer to problems. Opinions, controversy in medicine only occurs when there is room the responsibility to difference if we could reconcile differences in opinions through recognizing fundamental underlying principles. We have sought to seek a rational approach ‘Step-by-Step’ management of pediatric cataracts, to recognizing for different opinion, where is insufficient information for certainty. As Principal Editors, we had to determine what is clinical certainty, and what is not to debate and conclude a reasonable approach in response to the challenge for 8optimal cataract surgery and optical corrections for the management of dense cataract, present at birth. We take full responsibility for any editorial errors and/or omissions and at the same time acknowledge the advice and experience of Dr. Elie Dahan and Dr. Howard V. Gimbel during the development of the book. We acknowledge the support of our colleague, Dr. E. John Milverton, Chairman, Intraocular Implant Unit, Sydney Eye Hospital, Sydney, Australia.
It is a particular pleasure to acknowledge Dr. Creig S Hoyt, who has written the Foreword to this book. Creig, a long-time friend and colleague, a former fellow, but more importantly, a founding academic at the time of the appointment of the Foundation Professor of Ophthalmology in 1977 at University of Sydney, Department of Ophthalmology, sited on the campus of Sydney Eye Hospital. Creig now heads the Department of Ophthalmology at the University of California, San Francisco, USA. He is remembered for his seminal work in the early management of monocular cataract and neurophysiology, which has been stimulus to improve visual outcome in pediatric cataract surgery.
This work had truly been a team effort. It has been our intention from the outset to contribute to the understanding of cataract surgery in the presence of an immature visual system. We have been particularly interested in the first 2 years of life, where controversy and surgical difficulty are compounded due to the continued and changing morphology and anatomical dimension and optics of the eyes with development. If this book helps clarify what is known, and what is unknown and needs to be resolved, so that young people are encouraged to participate in finding answers and developing skills to relieve this form of blindness, our mission will be complete.9
The publisher of this book—Jaypee Brothers Medical Publishers (P) Ltd., New Delhi, India has become a leading name in the field of medical publication in a short period of 1 decade. We readily acknowledge the interest, and cooperation of Shri Jitendar P Vij, Chairman and Managing Director and appreciate his invitation to Edit this book. We thank all the staff, particularly, Mr Tarun Duneja, General Manager (Publishing), Mr PS Ghuman, Senior Production Manager, Ms Sunita Katla, Layout Designer and Ms Seema Dogra, Graphic Designer in assisting our participation in this Step by Step series on Pediatric Cataract Surgery. Finally we acknowledge the support of our families and their encouragement that has allowed us to meet deadlines and to complete this work.
Suresh K Pandey md
- Achievement Awardee
American Academy of Ophthalmology (2003)
- Intraocular Implant Unit
Sydney Hospital & Sydney Eye Hospital
Macquarie St, Sydney 2001, Australia
- Scholar of the University of Sydney
Save Sight Institute and Discipline of
Ophthalmology, Sydney, NSW, Australia 2001
- Assistant Professor
John A. Moran Eye Center
Department of Ophthalmology & Visual Sciences
University of Utah, 50 North Medical Drive
Salt Lake City, Utah-84132, USA
- Formerly Postdoctoral Fellow
Department of Ophthalmology
Albert Florens Storm Eye Institute
Medical University of South Carolina
Charleston, SC-29425, USA
Frank A Billson ao, franzco, fracs, frcs (lon), frcophth, facs
Founding Professor of Ophthalmology
Founding Director Save Sight Institute
Centre for Ophthalmology and Visual Sciences
Head of Discipline of Ophthalmology
University of Sydney
Campus of Sydney Hospital & Sydney Eye Hospital
8 Maquarie Street
Sydney, Australia
10
11Contributors 17Introduction
Cataract Surgery in Infancy and Childhood: Evolution, Principles and Practice
Frank A Billson
Suresh K Pandey18
 
CONVERGENCE OF TECHNOLOGIES
Small incision cataract surgery developed from pediatric cataract surgery whereas the evolution of intraocular lens (IOL) implantation has been driven from adult cataract surgery.– Historically, couching was the first described technique of adult cataract surgery (). presents an overview of evolution of cataract surgery in adults. Modern adult cataract surgery begins with the work of Jacques Daviel during the later 1800 described the principles of extracapsular cataract surgery ().
1A:
19
1B:
FIGURES 1A to C: Technique of couching to dislocate the cataractous lens into the vitreous. The couching may have been in ancient India by Susruta – “The father of Indian medicine” (800 BC). He was the first to practice and teach surgical principles. Susruta's life is placed well before the Hippocratic period. It is also known that couching was practiced by ancient Romans, Alexandrian Greeks, and Arabs before the time of Christ. It restored sight to numerous patients, although it was temporary due to a high rate of complications.
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Table 1   Evolution of techniques for adult cataract surgery
Technique
Year
Author/surgeon
Couching
800BC
Susutra
ECCE* (inferior incision)
1745
J Daviel
Discission needle
1811
Saunders
ECCE (superior incision)
1860
von Graefe
ICCE** (tumbling)
1880
H Smith
Zeigler's knife (looses AC)
1921
Zeigler
ECCE with PC-IOL***
1949
Harold Ridley
ECCE with AC-IOL****
1951
Strampelli
Phacoemulsification
1967
Charles Kelman
Discission needle (maintains AC)
1975
FA Billson
Foldable IOLs
1984
Mazzocco
Capsular Surgery
1992
DJ Apple
Accommodating IOLs
1997
Cummings/Kamman
Phakonit/Microphaco/MICS+
1998
A. Agarwal/RJ Olson/J Alio
Dye-enhanced Cataract Surgery
2000
S K Pandey/LWerner/DJ Apple
* ECCE: extracapsular cataract extraction;
** ICCE: intracapsular cataract extraction.
*** PC-IOL: posterior chamber intraocular lens;
**** AC-IOL: anterior chamber intraocular lens.
+ MICS: Microincision cataract surgery.
21
FIGURE 2: The First planned extraction of a cataractous lens was carried out by the French ophthalmologist Jacques Daviel.
His technique consisted of making an incision of the lower limbus. The capsule was then incised with a sharp needle. A spatula was inserted behind the iris and passed behind the lens. The lens was then expressed by gentle pressure
This required large limbal incision to deliver large hard nucleus of advanced cataract. In the middle of 20th century the advent of intracapsular cataract surgery (ICCE) demanded even larger incision to open the eyes and to deliver the lens.22
 
THE DISCIPLINE OF OCULAR MICROSURGERY
The later half of the 20th century saw a major advance in microsurgery for adult and pediatric cataract surgery. As the result of space ships and satellites new metals were developed making possible the advent of micro needles and miniaturization of eye surgical instruments and development of operating microscopes. The discipline of ocular microsurgery was born. Ocular microsurgery was the first microsurgery of the surgeries to involve suturing. Charles Kelman's, () development of phacoemulsification utilizing ultrasound to fragment the lens was a first step in facilitating the principal of safer small cataract incision surgery in adults and maintenance of intraocular relationship during the surgeries.
FIGURE 3: Charles D. Kelman
23
 
ARTIFICIAL LENS IMPLANTATION
Sir Harold Ridley () was the pioneer of IOL implantation but did not have control to fully solve the problem of continuous maintaining the anterior chamber throughout the surgery. Prior to Ridley's invention and during the years he struggled for its acceptance, cataract patients endured long hospital stays and then convalesced with heavy aphakic glasses that distorted their vision considerably.
FIGURE 4: Sir Harold Ridley
24
 
EVOLUTION OF PEDIATRIC CATARACT SURGERY
The history of cataract surgery in children was first performed early in the last century with small needle incision of the cornea. The needle having entered the anterior chamber, needled the cataract, to expose the lens fibers to aqueous humor and natural absorption of the lens fibers. The person seen to be the father of pediatric cataract surgery was Saunders of Moorefield eye hospital, whose name is perpetuated in the Saunders' needle. A variety of needles were subsequently developed but many including the Zeigler needle were wrong in the principle of their construction, the tapered shaft and a blade creating an incision that leaked with chamber loss on introduction of the needle. Other needles observed the construction principle that twice the diameter of the blade width creates an incision whose circumference tightly fitted the needle shaft so that needling could occur for up to 10 minutes without loss of the anterior chamber (AC) while the needling was carefully performed.
Aspiration of the cataract was in the 1960s with push pull technique introducing a blunt needle on a syringe at the 9 or 3 o'clock meridian depending on the side the eye was operated. Later the Simcoe needle for aspiration and infusion was developed. These simple devices were used with minor alterations until Connor O Malley developed the Ocutome (Vitrector). At the meeting in Hawaii in 1976 at a workshop was held to promote the instrumentation for vitrectomy. The instrumentation clearly 25also had potential to have application for pediatrics cataract surgery. The early experience was reported in 1981 and it remained applicable for young people up to the age of 30 years until the appearance of phacoemulsification. It remains the instrument of choice for many surgeons in the first two years of life.
 
IOL IMPLANTATION IN CHILDREN
Edward Epstein () of South Africa was first to use Ridley IOL in a child. Use of IOLs in children more than 2 years became standard of care since past few years.–
FIGURE 5: Edward Epstein
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Table 2   Evolution of pediatric cataract-IOL surgery
Advances
Year
Author(s)
First Implant in a Child for the Aphakic Correction
1958
E Epstein
Manual Aspiration of Congenital/Juvenile Cataract
1960
Scheie
Iridocapsular Implant
1969
C Binkhorst
Binkhorst Intraocular Lenses (IOLs)
1977–82
D Hiles
Posterior Chamber IOLs
1982
Hiles
Iris -Claw Lenses
1983
D Singh
Pathophysiology of Amblyopia
1977–85
Huebel/Weisel
Ocutome in vitrectomy
70s
O Malley
Ocutome in children
81
FA Billson
Posterior Chamber IOLs
83–93
R Sinskey/D Hiles
Posterior Capsulotomy/Anterior Vitrectomy
1983
M Parks
Epikeratophakia
1986
Morgan
27
Epilenticular IOL/Pars Plana Endocapsular Lensectomy
1988
Tablante
Retropseudophakic Vitrectomy via Limbus
1991
R Mackool/Chhatiawala
Retropseudophakic Vitrectomy+ Posterior Capsulectomy via Pars Plana
1993
E. Buckley
Primary Posterior Capsulorhexis/ Optic Capture
1994
HV Gimbel
IOL Biomaterials/Designs/Sizing in Children
1994
ME Wilson
Primary Posterior Capsulotomy & Ant. Vitrectomy
1994–96
BenEzra/Cohen Koch/Kohnen
Anterior Capsulotomy for Pediatric Cataract Surgery
1994
Wilson et al. (Vitrectorhexis) Auffarth et al.(Rabbit Model)
Heparin in BSS to Decrease Postoperative Inflammation
1995
Brady
Dyes for Pediatric Cataract Surgery
2000
Pandey/Wakabayashi/Jain
Foldable IOLs in children
2004
Pandey/Wilson/Apple
28
presents some of the milestones in the field of childhood cataract-IOL surgery since first pediatric IOL implantation performed by Edward Epstein. The drive to smaller and ultrasmaller incision surgery continues with development of foldable and microincision IOLs. More recently dividing the modalities and separating the irrigation from phacoemulsification for a bimanual system has reduced the size of phacoemulsification incision to 2 ultrasmall incisions.
 
PRINCIPLES AND PRACTICE OF PEDIATRIC CATARACT SURGERY
 
ANATOMICAL AND ANESTHETIC CONSIDERATION FROM BIRTH TO AGE 2
Cataract surgery is particularly important in first two years of life in an eye with changing anatomy. An immature visual system at this time implies the risks of amblyopia in the critical periods of development. At birth the axial length is approximately 17 mm increasing to 21 within the first two years of life. At birth the ora serrata abuts the ciliary body 2.2 mm from the limbus. The most rapid growth occurs in the first two years of life by the end of which the ora serrata is 7–8 mm from the limbus. The importance of this is that posterior approach to the lens in posterior segment at birth demands a pars ciliara approach. Not only is this a challenge but anesthesia is also occurring in an immature organism with a changing and vulnerable a cardiopulmonary system and changing physiology and 29pharmacological needs. A sensitive hypothalamus and changing autonomic nervous system including oculo-cardiac reflexes that can threaten cardiac arrest poor temperature control and threat of hypoglycaemia. These are but the background to the challenges to the anesthetist to intubate a small trachea and understand the possible risks of malignant hyperthermia. The advances in western society with better visual outcomes with early surgery in addition to skills and technology available to the surgeon owes a great deal to the skills of anesthetists who have additional training in pediatric anesthesia and are competent to give safe anesthetics to infants on the first day of life.
 
IOL SAFETY IN INFANTS AND CHILDREN
The USA Food and Drug Administration (FDA) has been slow to accept the use of IOL for use in children under the age of 18 years except in the cases of unilateral cataract uncorrected by contact lens or by other means. In spite of this academic departments in university hospitals who stood aside during the development of adult IOL and did not participate in research and controlled trials have shared in the necessary trials in order to establish the place of IOL implantation as part of the optical correction following cataract surgery in infancy. Academic departments including the university of Sydney, department of ophthalmology have played a part in the systematic solving of the technical and functional problems associated with this surgery. An important part of the research as been 30to the commitment to research in primates exploring the development of human eye, seeking to understand the implications of development in the first year of life. In Lambert's work the Monkey infant study continues to grow for first 6 months despite optical correction. From this Lambert predictions confirmed the later experience that the human infant eyes continue to grow for the first two years of life despite optical correction. This changing refraction has to be faced into choice of IOL implanted during early infancy.
The common surgical goals for treatment of adult and pediatric cataract with small incision surgery, maintenance of intraocular structural relationship, minimal damage to IOL structures, is now occurring, resulting in a valuable dialogue in relation to appropriate technology for optical correction following cataract surgery in all age groups.
As a result technology for cataract surgery and IOL implantation in children has become routine without the morbidity that attended the early history of adult cataract surgery and IOL implantation. Today in children over the age of 2 years and older children have had soft foldable lenses implanted in the interest of reduction of corneal wound size as a part of surgery. Enlarging the corneal wound runs conversely to underlying principle of small incisions for cataract surgery in children and accounted for some of the reluctance initially shown by pediatric ophthalmologists to IOLs.
Currently various designs and biomaterials are available for use in children. Experimental studies using postmortem human eyes suggest that modern rigid and foldable IOLs, designed for the adult population, can be implanted in the capsular bag of infants and children.31
FIGURE 6: Foldable single-piece hydrophobic acrylic IOL implanted in postmortem pediatric eye aged 6 months showing well-maintained configuration of the capsular bag.
However, a variable degree of ovaling of the capsulorhexis opening and capsular bag stretch was seen after implantation of the adult-sized rigid and foldable IOLs. Miyake-Apple posterior video technique confirmed the well-maintained configuration of the capsular bag (with minimal ovaling) after the implantation of the single-piece hydrophobic acrylic lens in infants and children due to its flexible haptic design (). Foldable lens can be inserted using with injector system utilizing sub 3 mm incision.32
 
CURRENT SURGICAL APPROACH FOR CATARACT SURGERY IN INFANCY AND CHILDHOOD
Details on pediatric cataract surgery are provided in other chapters of this book. Here we present pertinent points for cataract surgery in children.
  1. Cataract surgery for infants and young children is usually undertaken with general anesthesia in an intubated infant in the first year of life overseen by an anesthetist with pediatric anesthetic equipment and special training anesthesia.
  2. An anterior chamber (AC) maintainer is inserted obliquely into the AC. It ensures the flow of balanced salt solution is peripheral and circumferential in the AC and maintain a constant intraocular structural relationship.
  3. Two 0.9 mm insertions are made to allow insertion into the anterior chamber of the divided modalities, ocutome vitrector and irrigating needle.
  4. Over the age of two continuous capsulorhexis is possible. Under the age of 2 years the ocutome vitrector make it easier to cut an aperture with centered diameter of 5–6 mm.
  5. The cataract is then aspirated through the ocutome suction.
  6. The posterior capsule then is subjected to posterior capsulectomy using the cutting mode of the ocutome vitrector. This is the followed by anterior vitrectomy 33best done with the posterior ocutome with the aperture reduced in area and the cutting rate increased. Our experience with the anterior vitrector is that the larger aperture drawing more vitreous into the mouth of the ocutome can produce traction on the retina and small preretinal hemorrhages.
Postoperative complications are discussed in later chapters, however, 2 complications deserve comments:
  1. Fibrinous response into the anterior chamber. This appears to be part of the cascade of events related to healing and is readily reversed if recognized and managed with tissue thromboplastin activator. The susceptibility to fibrinous response appears to have a racial and genetic basis that may occur in a number of members of a particular family.
  2. Later onset secondary rise in intraocular pressure. Even in the microphthalmic eye the raised pressure can be controlled glaucoma surgery (e.g. with Molteno implants). Furthermore there is an incidence of aphakic glaucoma with a higher incidence in micro-ophthalmic eyes that occurs whether or not the eyes 34have been operated for cataract in those cases where the anterior chamber angle is open. There is now strong body opinion that suggests anomalies in the drainage angle associated with micro-ophthalmos are the basis for the glaucoma.
 
SUBSTRATE FOR DEVELOPMENT OF VISUAL SYSTEM IN INFANCY AND EARLY CHILDHOOD
What remains dramatically distinctive about cataract surgery in infancy is that surgery occurs in an immature visual system. Visual development may be threatened by cataract if clear imaging on the retina of each eye is threatened. Cataract if obstructing vision sufficiently may cause visual deprivation in each of the critical periods of visual development. Dense cataract at birth must be treated and optically corrected during the most critical period that is for pattern recognition if vision is to be normal. To have a chance of normal vision, vision must be restored before the primitive binocular vision pathway is initiated at 3 months.
The deviation of one eye because of association with cataract can be treated with occlusion of the straight or fixing eye once the cataract is removed and optical correction in place. The critical period for strabismic amblyopia may continue some months, but may be reversed with occlusion therapy. The misaligned eyes with an imperfect view of the objects regarded may be at risk 35of poor vision because of dominance of the fixing eye. Difference in refraction due to removal of the crystalline lens in unilateral cataract may lead to anisometropia.
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  1. Billson FA, Tarr KH. Closed system intraocular surgery in young people. Trans Ophthalmol Soc N Z 1981; 33: 71–76.
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  1. Pandey SK, Wilson ME, Trivedi RH, Izak A, Macky TA, Werner L, Apple DJ. Pediatric cataract surgery and intraocular lens implantation: Current techniques, complications and management. Int Ophthalmol Clin 2001, 41: 175–96.
  1. Wilson ME, Pandey SK, Thakur J. Pediatric cataract surgery in the developing world. Br J Ophthalmol 2003; 87: 16–19.
  1. Wilson ME. Intraocular lens implantation: Has it become the standard of care for children? (Editorial). Ophthalmology 1996; 103: 1719–20.
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  1. Hoyt CS. Monocular congenital cataract. J Pediatr Ophthalmol Strabismus 1982; 19: 127–128.
  1. 36 Lambert SR, Aiyer A, Grossniklaus H. Infantile lensectomy and intraocular lens implantation with long-term follow-up in a monkey model. J Pediatr Ophthalmol Strabismus 1999; 36: 271–278.
  1. Sengpiel F, Blakemore C. The neural basis of suppression and amblyopia in strabismus. Eye 1996; 10: 250–258.