2021–2022 BCSC Basic and Clinical Science Course™,Section 3: Clinical Optics

393 Pages·2022·11.333 MB·English

by  coll

3
Clinical Optics
Last major revision 2018–2019
2021–2022
BCSC
Basic and Clinical
Science Course™
Published after collaborative
review with the European Board
of Ophthalmology subcommittee
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tinuing Medical Education (ACCME) to provide continuing medical education for physicians.
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the extent of their participation in the activity.
Originally released June 2018; reviewed for currency August 2020; CME expiration date: June 1, 2022.
™
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BCSC® volumes are designed to increase the physician’s ophthalmic knowledge through study and
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strate appropriate knowledge and participation in the activity by taking the posttest for Section 3
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Basic and Clinical Science Course
Christopher J. Rapuano, MD, Philadelphia, Pennsylvania
Senior Secretary for Clinical Education
J. Timothy Stout, MD, PhD, MBA, Houston, Texas
Secretary for Lifelong Learning and Assessment
Colin A. McCannel, MD, Los Angeles, California
BCSC Course Chair
Section 3
Faculty for the Major Revision
Scott E. Brodie, MD, PhD
Thomas F. Mauger, MD
Chair
Columbus, Ohio
New York, New York
Pankaj C. Gupta, MD Leon Strauss, MD, PhD
Cleveland, Ohio Baltimore, Maryland
Kristina Irsch, PhD
Edmond H. Thall, MD
Baltimore, Maryland
Highland Heights, Ohio
and Paris, France
Mary Lou Jackson, MD Joshua A. Young, MD
Vancouver, Canada New York, New York
The Academy wishes to acknowledge the following committees for review of this edition:
Vision Rehabilitation Committee: Joseph L. Fontenot, MD, Mobile, Alabama
Practicing Ophthalmologists Advisory Committee for Education: Bradley D. Fouraker, MD,
Primary Reviewer, Tampa, Florida; Edward K. Isbey III, MD, Chair, Asheville, North
Carolina; Alice Bashinsky, MD, Asheville, North Carolina; David J. Browning, MD, PhD,
Charlotte, North Carolina; Steven J. Grosser, MD, Golden Valley, Minnesota; Stephen R.
Klapper, MD, Carmel, Indiana; James A. Savage, MD, Memphis, Tennessee; Michelle S.
Ying, MD, Ladson, South Carolina
European Board of Ophthalmology: Tero T. Kivelä, MD, EBO Chair, Helsinki, Finland;
Peter J. Ringens, MD, PhD, EBO Liaison, Maastricht, Netherlands; Jorge L. Alio, MD, PhD,
Alicante, Spain; Vytautas Jasinskas, MD, Kaunas, Lithuania; Eija T. Vesti, MD, Turku,
Finland
Financial Disclosures
Academy staff members who contributed to the development of this product state that
within the 12 months prior to their contributions to this CME activity and for the dura-
tion of development, they have had no financial interest in or other relationship with any
entity discussed in this course that produces, markets, resells, or distributes ophthalmic
health care goods or services consumed by or used in patients, or with any competing
commercial product or service.
The authors and reviewers state that within the 12 months prior to their contributions
to this CME activity and for the duration of development, they have had the following
financial relationships:*
Dr Alio: Akkolens (C, S), Bloss Group (L), Bluegreen Medical (O), Carevision (C, S), Carl
Zeiss Meditec (S), CSO Costruzione Strumenti Oftalmici (C), Dompé (S), Hanita Lenses (C),
International Ophthalmolgy Consulting (O), Jaypee Brothers (P), KeraMed (C, S),
Magrabi Hospital (C), Mediphacos (C), Novagali Pharmaceuticals (S), Oculentis (C, S),
Oftalcare Nutravision (O), Omeros (C), OPHTEC (L), Presbia (C), Schwind Eye Tech
Solutions (L, S), Tekia (P), Topcon (C)
Dr Brodie: Sanofi (L)
Dr Browning: Aerpio Therapeutics (S), Alcon Laboratories (S), Alimera Sciences (C),
Genentech (S), Novartis Pharmaceuticals (S), Ohr Pharmaceuticals (S), Pfizer (S), Regen-
eron Pharmaceuticals (S), Zeiss (O)
Dr Fouraker: Addition Technology (C, L), Alcon Laboratories (C, L), KeraVision (C, L),
OASIS Medical (C, L)
Dr Grosser: Injectsense (O), Ivantis (O)
Dr Isbey: Alcon Laboratories (S), Allscripts (C), Bausch + Lomb (S), Medflow (C), Oculos
Clinical Research (S)
Dr Jackson: Advanced Cell Technology (C), Astellas (C), Novartis Pharmaceuticals (C, L),
Visus Technology (C)
Dr Jasinskas: Alcon Laboratories (C)
Dr Vesti: Allergan (L), Santen (L), Thea (L)
The other authors and reviewers state that within the past 12 months prior to their contri-
butions to this CME activity and for the duration of development, they have had no finan-
cial interest in or other relationship with any entity discussed in this course that produces,
markets, resells, or distributes ophthalmic health care goods or services consumed by or
used in patients, or with any competing commercial product or service.
* C = consultant fee, paid advisory boards, or fees for attending a meeting; E = employed by or received
a W2 from a commercial company; L = lecture fees or honoraria, travel fees or reimbursements when
speaking at the invitation of a commercial company; O = equity ownership/stock options in publicly or
privately traded firms, excluding mutual funds; P = patents and/or royalties for intellectual property; S =
grant support or other financial support to the investigator from all sources, including research support
from government agencies, foundations, device manufacturers, and/or pharmaceutical companies
Recent Past Faculty
Dimitri T. Azar, MD
Nathalie F. Azar, MD
Kenneth J. Hoffer, MD
Tommy S. Korn, MD
In addition, the Academy gratefully acknowledges the contributions of numerous past
faculty and advisory committee members who have played an important role in the devel-
opment of previous editions of the Basic and Clinical Science Course.
American Academy of Ophthalmology Staff
Dale E. Fajardo, EdD, MBA, Vice President, Education
Beth Wilson, Director, Continuing Professional Development
Denise Evenson, Director, Brand & Creative
Ann McGuire, Acquisitions and Development Manager
Stephanie Tanaka, Publications Manager
Susan Malloy, Acquisitions Editor and Program Manager
Jasmine Chen, Manager of E-Learning
Lana Ip, Senior Designer
Beth Collins, Medical Editor
Eric Gerdes, Interactive Designer
Lynda Hanwella, Publications Specialist
American Academy of Ophthalmology
655 Beach Street
Box 7424
San Francisco, CA 94120-7424

Contents
Introduction to the BCSC . . . . . . . . . . . . . . . . . . . . . . xv
Objectives . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Introduction: Quick-Start Guide to Optics
and How to Refract . . . . . . . . . . . . . . . . . . . . . . . 3
Part 1: Introductory Optics . . . . . . . . . . . . . . . . . . . . . . 3
Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
The Tale of the Camera Obscura . . . . . . . . . . . . . . . . . . 4
Convex Lenses . . . . . . . . . . . . . . . . . . . . . . . . . . 8
Combining Lenses . . . . . . . . . . . . . . . . . . . . . . . . 9
Imaging Nearby Objects: Vergence and the Vergence
Equation . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Concave Lenses . . . . . . . . . . . . . . . . . . . . . . . . 11
Summary Thus Far . . . . . . . . . . . . . . . . . . . . . . . 11
Images in Denser Media . . . . . . . . . . . . . . . . . . . . . 12
A Very Much Simplified Model Eye . . . . . . . . . . . . . . . . 12
Astigmatism . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Astigmatic Refractive Errors . . . . . . . . . . . . . . . . . . . 19
Part 2: How to Refract . . . . . . . . . . . . . . . . . . . . . . . 20
Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Glossary . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Step 1: Perform the Preliminaries . . . . . . . . . . . . . . . . . 22
Step 2: Occlude 1 Eye . . . . . . . . . . . . . . . . . . . . . . 26
Step 3: Obtain Initial Estimate of the Refractive Error . . . . . . . . 27
Step 4: Refine Cylinder Axis and Power . . . . . . . . . . . . . . 29
Step 5: Refine Sphere Power . . . . . . . . . . . . . . . . . . . 33
Step 6: Occlude the Right Eye—Refract the Left Eye . . . . . . . . . 33
Step 7: Accommodative Control and Binocular Balance . . . . . . . 34
Step 8: Refraction at Near . . . . . . . . . . . . . . . . . . . . 36
Final Remarks . . . . . . . . . . . . . . . . . . . . . . . . . 38
1 Geometric Optics . . . . . . . . . . . . . . . . . . . . . . . 39
Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
vii
viii  Contents
Refractive Index . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Flat Refracting Surfaces—Snell’s Law . . . . . . . . . . . . . . . . . 44
Prisms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Prism Power . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Fresnel Prisms . . . . . . . . . . . . . . . . . . . . . . . . . 49
Critical Angle; Total Internal Reflection . . . . . . . . . . . . . . 50
Refraction by a Single Curved Surface . . . . . . . . . . . . . . . . . 51
Two-Sided Lenses . . . . . . . . . . . . . . . . . . . . . . . . . 54
Principal Planes . . . . . . . . . . . . . . . . . . . . . . . . 56
Depth of Focus and Depth of Field . . . . . . . . . . . . . . . . 57
General Refracting Systems . . . . . . . . . . . . . . . . . . . . . 58
Gaussian Optics . . . . . . . . . . . . . . . . . . . . . . . . 60
Real and Virtual Objects and Images . . . . . . . . . . . . . . . 60
Transverse Magnification . . . . . . . . . . . . . . . . . . . . 62
Axial (Longitudinal) Magnification . . . . . . . . . . . . . . . . 63
Conjugate Points . . . . . . . . . . . . . . . . . . . . . . . . 64
Ray Tracing . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Nodal Points . . . . . . . . . . . . . . . . . . . . . . . . . . 66
The Reduced, or Equivalent, Optical System . . . . . . . . . . . . . . 67
Aberrations . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Point Spread Function . . . . . . . . . . . . . . . . . . . . . . 69
Wavefront Theory. . . . . . . . . . . . . . . . . . . . . . . . 70
Chromatic Aberration . . . . . . . . . . . . . . . . . . . . . . 74
Astigmatism . . . . . . . . . . . . . . . . . . . . . . . . . . 74
The Conoid of Sturm . . . . . . . . . . . . . . . . . . . . . . 76
The Spherical Equivalent . . . . . . . . . . . . . . . . . . . . 76
The Power Cross . . . . . . . . . . . . . . . . . . . . . . . . 77
Power-Versus-Meridian Graph . . . . . . . . . . . . . . . . . . 79
Jackson Cross Cylinder . . . . . . . . . . . . . . . . . . . . . 80
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80
Telescopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83
Appendix 1.1. . . . . . . . . . . . . . . . . . . . . . . . . . . . 85
Derivation of the Vergence Equation and the
Lensmaker’s Equations from Snell’s Law . . . . . . . . . . . . . 85
Appendix 1.2 . . . . . . . . . . . . . . . . . . . . . . . . . . . 86
Fermat’s Principle . . . . . . . . . . . . . . . . . . . . . . . . 86
Appendix 1.3 . . . . . . . . . . . . . . . . . . . . . . . . . . . 88
Derivation of the Vergence Equation for Mirrors . . . . . . . . . . 88
2 Physical Optics . . . . . . . . . . . . . . . . . . . . . . . . 91
Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92
What Is Light? . . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Visible Light . . . . . . . . . . . . . . . . . . . . . . . . . . 93
Wave or Particle? . . . . . . . . . . . . . . . . . . . . . . . . 94
Contents  ix
Quantum Electrodynamics: Unifying Theory of Light . . . . . . . . . . 96
Refraction and Reflection . . . . . . . . . . . . . . . . . . . . 96
Scattering . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Phenomena of Light . . . . . . . . . . . . . . . . . . . . . . . . 98
Polarization . . . . . . . . . . . . . . . . . . . . . . . . . . 98
Coherence and Interference . . . . . . . . . . . . . . . . . . . 99
Diffraction . . . . . . . . . . . . . . . . . . . . . . . . . 104
Measures of Light . . . . . . . . . . . . . . . . . . . . . . . . . 106
Radiometry . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Photometry . . . . . . . . . . . . . . . . . . . . . . . . . . 108
Conversion Between Radiometric and Photometric Outputs . . . . . 110
Light Sources: Lasers . . . . . . . . . . . . . . . . . . . . . . . . 110
Fundamentals . . . . . . . . . . . . . . . . . . . . . . . . . 110
Therapeutic Laser–Tissue Interactions . . . . . . . . . . . . . . . 112
Light Hazards . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Appendix 2.1 . . . . . . . . . . . . . . . . . . . . . . . . . . . 119
Reconciliation of Geometric Optics and Physical Optics . . . . . . . 119
Chapter Exercises . . . . . . . . . . . . . . . . . . . . . . . . . 120
Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
3 Optics of the Human Eye . . . . . . . . . . . . . . . . . 123
Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 123
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Schematic Eyes . . . . . . . . . . . . . . . . . . . . . . . . . . . 125
Important Axes of the Eye . . . . . . . . . . . . . . . . . . . . . . 128
Pupil Size and Its Effect on Visual Resolution . . . . . . . . . . . . . 129
Visual Acuity . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Contrast Sensitivity and the Contrast Sensitivity Function . . . . . . . . 134
Refractive States of the Eyes . . . . . . . . . . . . . . . . . . . . . 136
Binocular States of the Eyes . . . . . . . . . . . . . . . . . . . . . 139
Accommodation and Presbyopia . . . . . . . . . . . . . . . . . . . 140
Epidemiology of Refractive Errors . . . . . . . . . . . . . . . . . . 141
Developmental Myopia . . . . . . . . . . . . . . . . . . . . . . . 142
Developmental Hyperopia . . . . . . . . . . . . . . . . . . . . . . 143
Prevention of Refractive Errors . . . . . . . . . . . . . . . . . . . . 144
Chapter Exercises . . . . . . . . . . . . . . . . . . . . . . . . . 144
Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Answers . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
4 Clinical Refraction . . . . . . . . . . . . . . . . . . . . . 147
Highlights . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Glossary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 147
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . 148
Minus Cylinder and Plus Cylinder Terminology . . . . . . . . . . . . 148
Exam Room Length . . . . . . . . . . . . . . . . . . . . . . . . 149