Ophthalmic Pathology: An Illustrated Guide for Clinicians

278 Pages·2005·29.454 MB·English

Ophthalmic
Pathology
An illustrated guide
for clinicians
Ophthalmic
Pathology
An illustrated guide
for clinicians
K Weng Sehu
Tennent Institute of Ophthalmology, University of Glasgow, UK
William R Lee
Tennent Institute of Ophthalmology, University of Glasgow, UK
© 2005 K.W. Sehu and W. R. Weng
Published by Blackwell Publishing Ltd
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First published in 2005
Library of Congress Cataloging-in-Publication Data
Sehu, K. Weng
Ophthalmic pathology: an illustrated guide for clinicians/K. Weng Sehu, William R. Lee
p.; cm.
includes index.
ISBN-13: 978 072791779 9 (alk. paper)
ISBN-10: 072791779 X (alk. paper)
1. Eye—Disease—Atlases 2. Eye—Diseases.
[DNLM: 1. Eye Diseases—pathology—Atlases.] I. Lee, William R., 1932– II. Title.
RE71.S44 2005
617.7—dc22
2005001742
A catalogue record for this title is available from the British Library
ISBN-13: 978 072791779 9
ISBN-10: 072791779 X
Set in Chennai, India by Newgen Imaging Systems (P) Ltd
Printed and bound in Haryana, India by Replika Press PVT Ltd.
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v
Contents
Preface,vii
Acknowledgements,ix
1 Basics,1
2 Eyelid and lacrimal sac,17
3 Conjunctiva,39
4 Cornea,61
5 Orbit and optic nerve,93
6 Development and malformation,121
7 Glaucoma,135
8 Inflammation,157
9 Wound healing and trauma,183
10 Retina:vascular diseases,degenerations,and dystrophies,203
11 Intraocular tumours,243
Index,269
vii
Preface
Our original purpose in writing this book was to make available illustrations of the common pathological
entities encountered in routine practice for junior colleagues who are undertaking postgraduate training.
In so doing, we have attempted to provide an understanding of the basic processes involved in oph-
thalmic disease and thus this book should also be of interest to qualified ophthalmologists. Computer
technology has advanced to such a level that it has enabled us to derive and modify images collected
over a period of 40 years. A CD ROM has been created as it provides the highest quality annotated illus-
trations that are easily accessible with the additional facility to remove the annotations for self-testing.
The electronic images allow viewing of screen illustrations at much higher magnifications than would be
possible in a printed textbook. An illustrated text has also been prepared for portable convenience.
Basic clinical and management sections have been added into each chapter to provide relevant back-
ground to the pathology presented. As a result, we hope that this book will also be of value to those
pathologists with an interest in ophthalmic pathology by helping to bridge the gap between laboratory
and clinical practice.
Weng Sehu
William Lee
ix
Acknowledgements
It is our pleasure to acknowledge the help and advice we have received from Dr Fiona Roberts,
DrRidia Lim, Professor Peter McCluskey, and Dr Harald Schilling.
Dedication
To our respective families.
Ophthalmic Pathology: An illustrated guide for clinicians
K Weng Sehu, William R Lee
Copyright © 2005 by K. W. Sehu and W. R. Weng
1
Chapter 1
Basics
2 CHAPTER 1
In order to achieve a better understanding of disease the optic nerve and at the edge of the cornea to avoid trau-
processes occurring in different regions of the eye, this matic artefact to the main axial structures. After paraffin pro-
section describes the technology currently employed by cessing, the microtomist cuts into the centre of the eye. The
the histopathologist in the examination of tissue speci- orientation of the extraocular muscles on the posterior
mens referred by ophthalmologists. It is important to be aspect of the globe allows the pathologist to identify the side
aware of the range of laboratory services locally available. from which the globe was enucleated (Figure 1.6).
When there is a suspicion of infection, the relevant spe- Orientation of the specimen is vital if the correct plane of cut
cialist (bacteriologist/mycologist/virologist) should be is to be made.
consulted for advice concerning appropriate transport
media and therapy. The value of an accurate and concise
history cannot be overestimated and good collaboration Microscopic features
will be rewarding to both clinicians and laboratory spe-
cialists. These are described wherever relevant to pathology in the
corresponding chapters and are therefore only illustrated
briefly in this chapter. The histological features of each of
Examination of the enucleated eye the following tissues are annotated in detail:
• cornea (Figure1.7)
A formalin-fixed enucleated globe bears little resemblance • chamber angle (Figure1.8)
to the in vivoappearance due to opacification of the cornea, • iris (Figures1.8, 1.9)
lens, vitreous, and retina. Previous intervention, for example • ciliary body (Figures1.8, 1.10, 1.11)
removal of keratoplasty tissue, can produce secondary • lens (Figures1.9, 1.11)
damage to the anterior segment tissues (Figure1.1). In rou- • retina and choroid (Figure1.12)
tine practice, it is unwise to try to cut across the lens • optic disc (Figure1.13).
because this produces damage to the anterior segment but Features for identification of the age of a patient (in this
occasionally a suitable illustration can be provided case a child):
(Figure1.2). By dividing the globe in the coronal plane, the • thin Descemet’s membrane
pathologist has the advantage of examination of the lens • “finger-like ciliary processes”
and ciliary body from the posterior aspect (Figure1.3) and • intact, non-hyalinised ciliary muscle
the retina from the anterior aspect (Figure1.4). For demon- • absence of proliferations in the pars plana epithelium
stration purposes, it is possible to divide the optic nerve and • absence of sub-RPE (retinal pigment epithelium)
the lens (Figure1.5). In general, the globe is divided above deposits (for example drusen).
Basics - Normal eye
edge of trephine
Anterior Segment
anterior chamber
opaque lens iris sphincter muscle
posterior chamber
zonules
chamber
angle limbus
ciliary trabecular
body meshwork
LENS
underlying iris damage
opaque cor neal stroma pars plicata
Basics - Normal eye pars plana (ciliary processes) ciliary
Anterior Segment / Autopsy eye - Donor Cornea VITREOUS muscle
ora serrata
Figure 1.1 Figure 1.2
Figure 1.1 In the current litigious climate, the only normal autopsy material Figure 1.2 The anatomical features of the anterior segment are easily
available for study will be that used for donor keratoplasty. In this example, recognised. Note that formalin fixation leads to opacification of those tissues
formalin fixation accounts for opacification in the cornea and lens. Damage to (cornea, lens, zonules, and vitreous) which are normally transparent.
the iris is the result of the trephine.
BASICS 3
Basics - Normal eye Basics - Normal eye
Lens & ciliary body - Posterior view Posterior segment
ora serrata
fragmentation of blood
column in vascular arcade
pars plana
LENS
autolytic swelling
pars of macula
plicata
(ciliary
processes) radial opacities
RPE adenoma?
posterior
subcapsular macula lutea optic disc
cataract
Figure 1.3 Figure 1.4
Basics - Normal eye Basics - Normal eye
Horizontal section / Left eye lateral rectus macula Posterior view / Left eye superior obliuqe m.
insertion of superior vortex meninges
inferior obliuqe TEMPORAL SIDE veins
muscle superior rectus m. optic nerve with
central retinal artery
and veins
optic long posterior
disc vessels
lateral
rectus m.
medial
rectus m.
myelinated inferior ciliary branches
NASAL SIDE nerve fibres oblique m. of ophthalmic
artery
lamina cribrosa inferior rectus m.
medial rectus inferior vortex veins
Figure 1.5 Figure 1.6
Basics - Normal / Cornea corneal epithelium
Figure 1.3 Dividing the eye in the coronal plane provides the opportunity to
Bowman’s
layer examine the ciliary body and lens in detail. In this case, there is a subcapsular
cataract. The radial linear opacities in the lens substance are a common
degenerative feature in the elderly globe. Note that in the pars plicata, there are
ridges and troughs which explain the differing appearance of the ciliary
processes in Figures1.10 and 1.11.
Figure 1.4 In a globe removed at autopsy, there is often autolytic swelling of the
stroma macula due to delayed fixation. The opacification of the retina is the result of
formalin fixation. After cessation of blood flow, the blood columns in the vessels
tend to fragment (“cattle-trucking”).
Figure 1.5 This normal globe is part of an exenteration and is fixed in
keratocytes
Descemet’s gluteraldehyde. For demonstration purposes, the section passes through the
membrane centre of the optic nerve, the lens, and the pupil (left). The macula is located on
the temporal side of the optic nerve, which is confirmed by the adjacent scleral
insertion of the inferior oblique muscle. The distance from the optic nerve to the
ora is greater on the temporal side than on the nasal side. A higher
corneal endothelium
magnification of the posterior pole of the globe is shown on the right. Myelination
Figure 1.7
of the axons in the optic nerve ends at the lamina cribrosa.
Figure 1.6 The orientation of the extraocular muscles in relation to the optic
nerve reveals that this specimen is a left globe.
Figure 1.7 A full thickness section of the cornea (left) demonstrates
the relative thinness of the epithelium and endothelium in relation to
the stroma. Both cell layers are shown in higher magnification (upper
right and lower right). Note the artefactual separation of the
corneal lamellae.
4 CHAPTER 1
Basics - Normal eye INFANT Basics - Normal eye stroma melanocytes sphincter
Anterior chamber angle Iris and lens clump cells pupillae
longitudinal fibres scleral spur crypt
of ciliary muscle artery ANTERIOR CHAMBER
Schlemm’s canal
hyalinisation
circular fibres
trabecular meshwork
bilayered iris pigment
thin“finger-like” dilator epithelium
ciliary processes pupillae
iris stroma POSTERIOR CHAMBER
dilator pupillae
epithelium anterior capsule
stubby
ciliary processes LENS
pigment epithelium
Figure 1.8 Figure 1.9
Basics - Normal eye Basics - Normal eye
Ciliary body Ciliary body and lens
outer pigmented layer
sclera conjunctiva continuous with RPE
inner
non-pigmented
layer continuous CILIARY PR OCESSES
with retina
VITREOUS
bilayered ciliary
epithelium
zonules
vitreal face
pars plana
chamber capsule
ciliary muscle angle epithelium
zonular fibres pars plicata
VITREOUS (ciliary processes) nuclear bow LENS
Figure 1.10 Figure 1.11
ILM Figure 1.8 Hyalinisation and atrophy of the circular and oblique components of the
NFL ciliary muscle is a feature of ageing, but the longitudinal fibres inserting into the
GCL
IPL scleral spur persist. In an infant (inset), the components of the ciliary muscle are
INL intact: note the thin ciliary processes.
Figure 1.9 In the pupillary portion of the iris, the sphincter pupillae is a prominent
OPL feature and the close relationship to the lens provides the opportunity to illustrate
ONL cones the anterior capsule and the epithelium of lens. The iris pigment epithelium
terminates at the pupillary rim in the normal eye.
OLM rods
Figure 1.10 In this illustration of the normal ciliary body, the relative absence of
PR IS
PR OS Bruch’s membrane hyalinisation in the ciliary muscle suggests the younger age of the patient. This
RPE choriocapillaris section passes through one of the troughs in the pars plicata.
Figure 1.11 The ciliary processes are lined by a two-layered epithelium
CHOROID
corresponding to the layers of the optic cup (see Chapter 6). The stroma of the
ciliary processes contains blood vessels. The equator of the lens contains the
nuclear bow. This section passes through a ridge in the pars plicata.
choroidal melanocytes
Figure 1.12 The normal histology of the retina, choroid, and sclera.
Basics - Normal eye SCLERA ILM(cid:2)inner limiting membrane, NFL(cid:2)nerve fibre layer, GCL(cid:2)ganglion cell
Retina and choroid layer, IPL(cid:2)inner plexiform layer, INL(cid:2)inner nuclear layer (bipolar cells),
Figure 1.12 OPL(cid:2)outer plexiform layer, ONL(cid:2)outer nuclear layer (photoreceptor
nuclei), PR(cid:2)photoreceptors in inner segment (IS) and outer segment (OS)
(cones have a distinctive pink inner segment), RPE(cid:2)retinal pigment
epithelium with underlying Bruch’s membrane and choriocapillaris. The
choroid contains blood vessels, nerves, fibroblasts, and melanocytes with
branching processes. The sclera is avascular and contains scattered scleral
fibroblasts.