Ophthalmic Ultrasonography and Ultrasound Biomicroscopy: A Clinical Guide

By Rasha Abbas

This book provides a visual overview of how to master ultrasonography and ultrasound biomicroscopy techniques. Updated ultrasonic information is included in a simple brief way, featuring  didactic points, with a variety of documented scans and illustrated lines underneath for more clarification. Each pathology is accompanied with several scans of different findings to give more information of distinct detections.

Ophthalmic Ultrasonography and Ultrasound Biomicroscopy: A Clinical Guide examines many clinical complexities with possible solutions when performing and interpreting ultrasound while also breaking down information for easier intake. The clinical cases are from a specialist eye hospital where many complicated cases are treated, giving a unique insight for the reader to understand treatment for a variety of cases. The book also emphasises the importance of everyday cases with further explanation whilst utilising a diversity of pictures and labels.

• Language: English
• Publisher: Springer
• Release date: Jul 3, 2021
• ISBN: 9783030769796

Book preview

Rasha Abbas

Ophthalmic Ultrasonography and Ultrasound Biomicroscopy

A Clinical Guide

1st ed. 2021

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Rasha Abbas

Ultrasound Department, Watany Eye Hospital, Cairo, Egypt

ISBN 978-3-030-76978-9e-ISBN 978-3-030-76979-6

https://doi.org/10.1007/978-3-030-76979-6

© The Editor(s) (if applicable) and The Author(s), under exclusive license to Springer Nature Switzerland AG 2021

This work is subject to copyright. All rights are solely and exclusively licensed by the Publisher, whether the whole or part of the material is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in any other physical way, and transmission or information storage and retrieval, electronic adaptation, computer software, or by similar or dissimilar methodology now known or hereafter developed.

The use of general descriptive names, registered names, trademarks, service marks, etc. in this publication does not imply, even in the absence of a specific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use.

The publisher, the authors and the editors are safe to assume that the advice and information in this book are believed to be true and accurate at the date of publication. Neither the publisher nor the authors or the editors give a warranty, expressed or implied, with respect to the material contained herein or for any errors or omissions that may have been made. The publisher remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

This Springer imprint is published by the registered company Springer Nature Switzerland AG

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Preface

This book is designed to help ophthalmologists better understand ocular sonography and its invaluable importance in the different fields of ophthalmology.

It offers a comprehensive guide with detailed information on the major aspects of ocular sonography, illustrated throughout with examples to provide the specialists with an overview on the different topics.

It is intended to give guidance on the basics of ocular sonography, as well as the key manifestations of different ocular diseases.

It is my hope and expectation that this book will provide effective learning experience and referenced resource for all ophthalmologists.

Rasha Abbas

Cairo, Egypt

Acknowledgments

Writing this book has been a surreal journey. It was both internally challenging and rewarding. I would like to take this opportunity to thank each individual who helped to make this happen.

First and foremost, I have to start by thanking my family for their ongoing support. This book would not have been possible without the endless patience and continuous encouragement of my lovely husband Ayman.

I’m indebted to Watany Eye Hospital team for supporting and giving me the opportunity to reach my goal.

I’m eternally grateful to my friends and colleagues for their insightful feedback and enthusiastic support. The support of the publisher and the collaboration of the editorial staff are warmly acknowledged.

I would like to express my appreciation and gratitude to the late Prof. Dr. Riyad Fikry, a special thanks to Prof. Dr. Nader Fathy, and lastly a heartfelt thanks to Marwa Faried and Dr. Samar sherif for their appreciated assistance.

Contents

1 Introduction and Ultrasound Examination 1

1.​1 Physical Principles 1

1.​2 Instruments 2

1.​3 Clinical Application 2

1.​3.​1 Before Preforming B-Scan Examination 2

1.​3.​2 B-Scan Positioning and Examination 3

1.​3.​3 B-Scan Probe Orientation 3

1.​4 Diagnostic A-Scan:​ 9

1.​4.​1 Quantitative Echography 12

1.​4.​2 Kinetic Echography 16

References 17

2 UBM Examination 19

2.​1 Technique 19

2.​2 UBM Probe Positions 19

2.​2.​1 Axial Scan 19

2.​2.​2 Longitudinal Scan 20

2.​2.​3 Transverse Scan 21

2.​3 The 10 Parameters Defined by Pavlin Et Al Which Are Commonly Used for Image Analysis of UBM [6] (Fig.​ 2.​7) 25

References 26

3 Vitreoretinal Disease 29

3.​1 Vitreous 29

3.​1.​1 Asteroid Hyalosis 29

3.​1.​2 Vitreous Hemorrhage 31

3.​1.​3 Subhyaloid Hge 33

3.​2 Retina 36

3.​2.​1 Rhegmatogenous Retinal Detachment 37

3.​2.​2 Retinal Tears 39

3.​2.​3 Traction Retinal Detachment 41

3.​2.​4 Exudative Retinal Detachment 44

3.​2.​5 Differential Diagnosis:​ 45

3.​2.​6 Funnel Retinal Detachment:​ Long-standing Detachments 48

3.​3 Choroid 48

3.​3.​1 Choroidal Detachment:​ 48

3.​4 Intraocular Silicone 56

References 60

4 Ocular Trauma 63

4.​1 Anterior Segment 63

4.​1.​1 Angle Recession 63

4.​1.​2 Cyclodialysis 63

4.​1.​3 Iridodialysis 65

4.​1.​4 Traumatic Lens and IOL Disorders 69

4.​1.​5 Foreign Bodies (F.​B) 73

4.​2 Posterior Segment 78

References 109

5 Congenital Anomalies and Pediatric Eye Diseases 111

5.​1 Limbal Dermoid 111

5.​2 Peter’s Anomly 115

5.​3 Axenfeld-Rieger Syndrome 119

5.​4 Aniridia 120

5.​5 Posterior Lenticonus 122

5.​6 Persistent Fetal Vasculature (PFV) 124

5.​7 Retinopathy of Prematurity (ROP) 130

5.​8 Coats Disease 136

5.​9 Retinoblastoma 138

5.​10 Coloboma 144

References 150

6 Ocular Tumors 153

6.​1 Anterior Segment Tumors 153

6.​1.​1 Iris Lesions 153

6.​1.​2 Ciliary Body Tumors 156

6.​2 Choroidal Melanoma 158

6.​2.​1 Shape and Reflectivity 158

6.​2.​2 Sound Attenuation 159

6.​2.​3 Choroidal Excavation 159

6.​2.​4 Posterior Scleral Bowing 159

6.​2.​5 Exudative Retinal Detachment 159

6.​2.​6 Extrascleral Extension 159

6.​2.​7 Measurement of the Tumor 164

6.​3 Choroidal Hemangioma 167

6.​3.​1 Circumscribed Hemangioma 167

6.​3.​2 Diffuse Hemangioma 168

6.​4 Metastsis 169

6.​5 Choroidal Nevus 172

6.​6 Choroidal Osteoma 172

6.​6.​1 Sclerochoroidal Calcification 173

References 177

7 Inflammatory Diseases of the Eye 181

7.​1 Anterior Uveitis 181

7.​2 Intermediate Uveitis 183

7.​3 Posterior Uveitis 187

7.​4 Endophthalmitis 187

7.​5 Vogt-Koyanagi-Harada 188

7.​6 Toxocariasis 192

7.​7 Cysticercosis 198

7.​8 Lens and IOL Induced Uveitis 198

7.​9 Scleritis 199

7.​9.​1 Diffuse Scleritis 201

7.​9.​2 Nodular and Necrotic Scleritis 207

References 209

8 Glaucoma 213

8.​1 Angle Closure Glaucoma 213

8.​1.​1 Pupillary Block 213

8.​1.​2 Plateau Iris 218

8.​1.​3 Malignant Glaucoma 219

8.​2 Open Angle Glaucoma 221

8.​2.​1 Pigment Dispersion Syndrome 221

8.​3 UBM in Assessing Efficacy of Therapy 223

8.​3.​1 Laser Peripheral Iridotomy 223

8.​3.​2 Surgical Iridectomy 224

8.​3.​3 Post-Glaucoma Surgery 224

8.​3.​4 Glaucoma Implants (Tubes, Tube Shunts, Valves) 231

8.​4 Secondary Glaucoma 233

8.​5 Congenital Glaucoma 238

References 247

9 Optic Nerve Diseases 251

9.​1 Optic Nerve Enlargement 251

9.​2 Optic Nerve Lesions 259

9.​2.​1 Optic Nerve Glioma 259

9.​2.​2 Melanocytoma 260

9.​3 Optic Disc Drusen 262

9.​4 Optic Nerve Cupping 263

9.​5 Coloboma 263

9.​5.​1 Morning Glory Disc Anomaly 263

References 265

Contributors

Sherif N. EmbabiM.D., Ph.D.

Professer of Ophthalmology Ain Shams University, Vitreoretinal Consultant Watany Eye Hospital, Cairo, Egypt

Terese KamalM.D., FRCS

Uveitis Consultant, Watany Eye Hospital, Cairo, Egypt

Fathy Fawzy MorkosM.Sc., FRCS, FRCO.

Professor of Ophthalmology in Military Medical Academy (Subspecialty: Anterior Segment Reconstruction, Cataract and Refractive Surgery), Chairman and Co-Founder of Watany Eye Hospital, Cairo, Egypt

© The Author(s), under exclusive license to Springer Nature Switzerland AG 2021

R. AbbasOphthalmic Ultrasonography and Ultrasound Biomicroscopyhttps://doi.org/10.1007/978-3-030-76979-6_1

1. Introduction and Ultrasound Examination

Rasha Abbas¹  

(1)

Ultrasound Department, Watany Eye Hospital, Cairo, Egypt

1.1 Physical Principles

Echoes: Echoes are produced by acoustic interfaces created at the junction of two media that have different acoustic impedance.

Acoustic impedance: The difference between the strength of the returning echoes from tissue boundaries with abrupt changes in acoustic properties. For example the anterior lens surface produces a stronger echo when bordered with aqueous than with hyphema because the difference between the lens and aqueous is greater than the difference in impedance between the lens and the blood.

Angle of incidence: The angle at which the sound beam strikes an interface is an important factor in the strength of the returning echoes. The more perpendicular the beam, the stronger is the returning echo.

Pulse echo system: The basic unit which includes a piezoelectric transducer to generate the ultrasonic wave, a receiver which processes the returning waves and a display screen.

Frequency: It is used in ophthalmic ultrasound ranging between 8–80 MHz [5, 10] compared to 2–6 MHz used in other fields of diagnostic ultrasound.

Resolution: The ability to distinguish between adjacent echoes, both axial(distance between two reflectors distinguishable from each other along the direction of acoustic propagation) and lateral (ability to distinguish the two reflectors positioned next to each other with respect to the ultrasound beam axis). This is enhanced by the use of a focused sound beam [6].

Gain: This is the procedure of increasing or decreasing the amplitude of echoes that are displayed on the screen.

Absorption: Ultrasound wave is absorbed by every medium through which it passes. The more dense the medium, the more absorption of the wave [2].

Display of signals: The received ultrasound signal can be displayed in three ways: A mode, B mode or a combination of both. Other modifications include the three-dimensional ultrasound, which uses a rotating transducer rather than the oscillating one used in the conventional ultrasound system and a combination of color Doppler with the B scan.

1.2 Instruments

A scan:

A-scan is a one-dimensional display of echo strength over time, There are two types of ultrasound A-scans: Biometric A-scan and standardized A-scan.

Biometric A-scan: used primarily for axial length measurement, using a probe with 10–12 MHz and a linear amplification curve.

Standardized A-scan: Pioneered by Ossoining, standardized A-scan was developed as a diagnostic tool in ophthalmology, It incorporate the S-shaped amplitude, which provide the benefit of the wide range of logarithmic amplification and the high sensitivity of linear amplification. Standardized A-scan utilizes an operating frequency of 8 MHz [1, 7, 8, 15].

B-scan:

B-scan is a two-dimensional brightness display, where the strength of the returning echo is displayed as a dot on the screen. The brightness intensity is proportional to the echo amplitude [6, 9, 11, 13, 18].

1.3 Clinical Application

1.3.1 Before Preforming B-Scan Examination

History taking and clinical examination of the eye are crucial initial steps before performing ophthalmic ultrasonography. History taking traditionally includes the presenting complaint, previous investigations or treatment related to the complaint, previous ocular surgeries, ocular traumas; as well as significant systemic illness and family history.

1.3.2 B-Scan Positioning and Examination

*Ultrasound examination is performed in the supine or sitting position.

*The probe is placed directly over the conjunctiva or cornea or placed over closed lids. The former has the advantage of reducing the sound attenuation caused by the lids; sterilization of the probe between procedures is mandatory [17].

*In cases of congenital anomalies and tumors, Examination of the other eye is mandatory.

*In cases of congenital anomalies, developmental glaucomas and trauma, comparing axial length measurements is recommended.

1.3.3 B-Scan Probe Orientation

The three basic probe orientation that are commonly used are axial, transverse and longitudinal scans.

A) Axial scan:

The Probe is directly applied to the cornea with the patient fixating in the primary gaze, The lens and optic nerve are displayed at the center of the scan.

In Vertical axial scan, the marker is placed in the superior position to examine the retina above and below the optic disc (Fig. 1.1).

In Horizontal axial scan, the marker is placed towards the patient nose which place the macular area below the optic disc (Fig. 1.2).

In Oblique axial scan, the marker is placed towards the upper of the two meridian examined (Fig. 1.3).

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Fig. 1.1

Vertical axial B-scan, a the patient’s eye in the primary gaze, and the probe is placed on the cornea, with the probe marker directed superiorly (black arrow), b B-scan showing the lens anteriorly and the optic nerve posteriorly with the upper part of the scan representing the superior portion of the globe (12 o’clock) and the lower part of the scan representing the inferior portion of the globe (6 o’clock). O.N: optic nerve

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Fig. 1.2

Horizontal axial B-scan: a the patient’s eye is in the primary gaze, the probe is placed on the cornea with the marker oriented nasally, b axial B-scan showing the lens anteriorly and the optic nerve posteriorly with the upper part of the scan representing the nasal portion of the globe (3 o’clock) and the lower