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Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_4458_Библиотеки_им_академика_М_И_Перельмана
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Radiological Imaging inRhinology
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AndrewS.McQueen andJoannaK.Dixon
14
Introduction
The evolution of radiology in the last few decades
has revolutionised assessment of the nose and
sinuses. The emergence of widely available, high
resolution, three-dimensional imaging has established a key role for imaging in the diagnosis and
management of sinonasal pathology. In addition
to pre-operative planning, modern imaging can
be rapidly acquired and is regularly fused with
intra-operative endoscopy by navigation software, enabling increasingly accurate imageguided surgery (IGS) to reduce operative time
and complications.
This chapter provides a concise overview of
nose and paranasal sinus imaging: a foundation
to help the reader appreciate the role of radiology
within each clinical rhinology chapter.
Radiological anatomy is highlighted, with reference to clinically relevant anatomic variants,
imaging pitfalls and the communication of ndings to enable accurate diagnosis and appropriate
management (the radiology report). Sinonasal
imaging techniques are described with the
strengths and limitations of each different modality discussed in the context of common clinical
scenarios. Finally, in an area of constant change
A. S. McQueen (*) · J. K. Dixon
Department of Radiology, Freeman Hospital,
Newcastle upon Tyne Hospitals NHS Foundation
Trust, Newcastle upon Tyne, UK
e-mail: andrew.mcqueen1@nhs.net
and development, future trends in clinical imaging will be considered.
Clinically Applied Imaging Anatomy
Key Anatomic Findings andNormal
Variants
The following section aims to highlight some of
the key, surgically relevant anatomical structures
of the sinonasal cavity and their common variants,
which when present may impair sinus drainage or
increase the risk of complication associated with
functional endoscopic sinus surgery (FESS) [1–8].
The terminology used within the body of this section is that recommended by the 2014 European
Position Paper on Anatomical Terminology of the
Internal Nose and Paranasal Sinuses [9], with reference also made to the International Frontal Sinus
Anatomy Classication (IFAC) [10].
Basic Anatomy oftheNasal Cavity
The nasal septum divides the nasal cavity in the
sagittal plane. Varying degrees of septal deviation, septal spurs and adhesions may be present
and posteriorly the septum may be pneumatised
from the sphenoid sinuses (Fig.14.1). The turbinates (inferior, middle, superior and occasionally
supreme) divide the nasal cavity in the axial
plane into their respective meatus and may be
paradoxical or pneumatised (Fig. 14.2a–g).
© The Author(s), under exclusive license to Springer Nature Switzerland AG 2023
A. C. Swift et al. (eds.), Contemporary Rhinology: Science and Practice,
https://doi.org/10.1007/978-3-031-28690-2_14
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A. S. McQueen and J. K. Dixon
a
c
Incisive
foramen
Severe septal
deviation
Cartilaginous
Septum
Perpendicular Plate
of Ethmoid
Maxillary crest
Vomer
b
Cartilaginous
Septum
Bony
Septum
d
e
Pneumatisation of the
posterior nasal septum
Fig. 14.1 The nasal septum. (a, b) Sagittal and axial CT
images demonstrating the anatomy of the nasal septum.
(c) Coronal CT showing severe septal deviation to the left.
Deviation is often accompanied by enlargement of the
Deviation/dislocation at
junction of maxillary crest
and quadrilateral cartilage
contralateral turbinates and ethmoid bulla. (d) Deviation/
dislocation at the chondrovomeral junction. (e)
Pneumatisation of the posterior septum, which usually
occurs from the sphenoid sinuses
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Appreciation of their complex attachments
requires image review in multiple planes
(Fig.14.3). The basal lamella of the middle turbinate is an important surgical and radiological
landmark as it forms the boundary between anterior and posterior ethmoid cells and therefore
separates the anterior from posterior sinus drainage pathways (Fig.14.4). These pathways will be
considered separately below.
The Anterior Paranasal Sinus Drainage
Pathway: Maxillary Sinus
andOsteomeatal Complex
The maxillary, frontal and anterior ethmoid sinus
cells all drain via the osteomeatal complex into
the nasopharynx (Fig. 14.5a). The osteomeatal
a
Paradoxical
superior
turbinate
b
complex is a functional unit comprising bony
structures (uncinate process, middle turbinate
and ethmoid bulla) and the anatomical spaces
that lie between them (maxillary ostium, ethmoid
infundibulum, semilunar hiatus and middle
meatus). Variations in any of these components
may lead to impaired sinus drainage (Fig.14.5b).
The anterior attachment of the uncinate process is variable, attaching either to the lamina
papyracea, anterior skull base or middle turbinate
and is of particular interest, as its position alters
the drainage pathway of the frontal sinus
(Fig. 14.6a–c). It has a free posterior border,
which parallels the anterior margin of the ethmoid bulla, usually the largest anterior ethmoid
cell. The crescent-shaped opening between the
Pneumatised superior
turbinate
Middle
Superior,
middle and
inferior
meatus
turbinate
Inferior
turbinate
c
Bilateral paradoxical
middle turbinates
Fig. 14.2 Anatomical variations of the nasal turbinates.
(a) Paradoxical superior turbinates, (b) pneumatised superior turbinates, (c) bilateral paradoxical middle turbinates.
Pneumatisation of the middle turbinate may involve the
turbinate itself (concha bullosa), the lamella only (d), or
may extend to involve both (e). Note that in this nal case
the pneumatised cell extends to the ethmoid roof
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A. S. McQueen and J. K. Dixon
d
Pneumatisation of
the middle
turbinate lamella
Fig. 14.2 (continued)
a
Left middle
concha bullosa
b
e
Pneumatisation of
the middle
turbinate and its
lamella
c
d
Fig. 14.3 Attachments of the middle turbinate are most
easily appreciated in the imaging plane perpendicular to
their long axis. Due to the complex conguration and
attachments of the middle turbinate, image review in all
three planes is required. (a–d) Anterior coronal, axial,
sagittal and posterior coronal images demonstrating the
two structures is the semilunar hiatus, which
forms the superior entrance to the ethmoidal
infundibulum. The uncinate process may be
pneumatised, everted, paradoxical or lateralised
and variations may lead to narrowing of the adjacent ethmoid infundibulum, the space formed
between the uncinate process medially and lamina papyracea laterally (Fig.14.6d–f).
anterior attachment that lies in the sagittal plan (green),
the middle attachment (basal lamella) that lies in the coronal plane (yellow), and the posterior attachment that lies
in the axial plane (red). In this example, due to the undulating nature of the basal lamella, it is represented several
times on this single axial image
The degree of pneumatisation of the maxillary
sinus is variable (Fig.14.7a). The sinus ostium
opens on the medial wall between the attachment
of the uncinate process and lamina papyracea and
drains into the ethmoid infundibulum. The position of the maxillary ostium is usually aligned
with the lamina papyracea on coronal images but
can be variable depending on the extent of sinus
ab
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Fig. 14.4 Anterior and posterior paranasal sinus drainage
pathways. (a) Parasagittal image showing the basal
lamella of the middle turbinate separating anterior and
posterior ethmoid cells and forming the boundary between
anterior and posterior drainage pathways. The anterior
drainage pathway is labelled. (b) Image from the same
patient showing the sphenoid sinus ostium opening into
the sphenoethmoidal recess, and posterior ethmoid cells
opening into the superior meatus, forming the posterior
drainage pathway
ab
Fig. 14.5 The osteomeatal complex (a) is a functional
unit that comprises the uncinate process (UP), semilunar
hiatus (yellow dotted line), maxillary ostium (white dot),
middle meatus (red dotted line), ethmoidal infundibulum
(blue dotted line) and ethmoid bulla. (b) Pneumatisation
of the middle turbinate and a large infraorbital (Haller)
cell causes distortion of the left osteomeatal complex,
although ethmoidal infundibulum remains patent. Note in
this example the maxillary ostium is more medially
located than usual in relation to the lamina papyracea
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A. S. McQueen and J. K. Dixon
a
Uncinate process
attachment to the
lamina papyracea
Uncinateprocess
attachment to the
middle turbinate
e
Uncinate process
pneumasaon
Fig. 14.6 Variations of the uncinate process. The anterior
attachment of the uncinate process (yellow line) determines the route of frontal sinus drainage (red dotted line):
(a) attachment to the lamina papyracea, with frontal sinus
drainage directly to the middle meatus, (b and c) attachment to the middle turbinate and anterior skull base with
frontal sinus drainage to the ethmoid infundibulum. The
cb
Uncinate process
attachment to the
anterior skull base
Everteduncinate
process
uncinate processes may be pneumatised (d), everted (e),
or laterally displaced (f). The lateral displacement results
in narrowing or occlusion of the ethmoid infundibulum.
Pressure changes within the obstructed maxillary sinus
may ultimately result in reduction in volume of the sinus
and depression of the orbital oor, known as Silent Sinus
Syndrome
Lateralised/atelectac
uncinate process
pneumatisation (Fig.14.5b). Haller (infraorbital)
cells are anterior ethmoid cells that extend inferior to the orbit, which may contribute to narrowing of the ethmoid infundibulum (Fig. 14.5b).
Accessory ostia are often present along the
medial wall of the sinus, posterior to the true
ostium (Fig.14.7b). The position of the infraorbital nerve canal may vary from its usual location
at the roof of the maxillary sinus, passing through
the sinus on a bony mesentery (Fig.14.7c–d).
The Anterior Paranasal Sinus Drainage
Pathway: Frontal Sinus, Frontal Sinus
Drainage Pathway (FSDP) andAnterior
Ethmoid Cells
The degree of frontal sinus pneumatisation is
variable and may directly involve the crista galli.
Diploic veins may traverse the sinus and—as
they are valveless—can provide a direct route for
spread of infection to the cavernous sinuses
(Fig.14.8a–d).
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a
b
cde
Fig. 14.7 Variations of the maxillary sinus. (a)
Pneumatisation of the maxillary sinuses is variable, in this
case there is pneumatisation medially between the nasal
cavity oor and hard palate (red arrows). (b) In the same
patient, bilateral accessory ostia are noted posterior to the
The frontal beak indicates the level of the
frontal sinus ostium, which separates the sinus
above from the FSDP below (Fig. 14.9a). The
anatomy of the FSDP is complex as it depends on
both the anterior attachment of the uncinate process (as discussed above) and the conguration
of the adjacent anterior ethmoid cells, which
form its walls. The anterior wall of the FSDP is
formed by the agger nasi cell, the most anterior
ethmoid cell and rst to be encountered on coro-
true ostia (green arrows). (c, d) The infraorbital nerve is
suspended within the maxillary sinus on a bony mesentery
putting it at risk of iatrogenic injury (yellow arrows). (e)
Infraorbital (Haller) cells (blue arrows) in this case are
seen extending up to the infraorbital nerve canal
nal imaging. The ethmoid bulla, usually the largest anterior ethmoid cell, forms the posterior wall
(along with suprabullar cells when present). The
medial wall is dependent on the uncinate attachment and may comprise the middle turbinate or
uncinate itself, whilst the lateral wall is formed
by the lamina papyracea or agger nasi cell
(Fig.14.6a–c). Enlargement of any of these cells
may lead to displacement and narrowing of the
FSDP.To appreciate the complex anatomy in this
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ab
A. S. McQueen and J. K. Dixon
Fig. 14.8 The frontal sinus. (a, b) The degree of frontal
sinus pneumatisation is variable and may involve the
crista galli (asterisk). (c, d) Diploic veins, which can
sometimes be seen to traverse the sinus, provide a direct
route for the spread of infection to the dural venous
sinuses, which puts the patient at risk of cavernous sinus
thrombosis (arrows)
abc
Fig. 14.9 The frontal sinus drainage pathway (FSDP).
(a) The frontal beak marks the level of the frontal sinus
ostium, inferior to which the frontal sinus drainage pathway is formed. (b) When enlarged, the agger nasi cell
(AN) and ethmoid bulla (EB) can narrow the frontal sinus
area, images must be reviewed in all planes
(Fig.14.9b–c).
Frontoethmoid cells are a subset of anterior
ethmoid cells that extend superiorly beyond the
frontal beak into the frontal sinus, for which
classication systems have been described [11].
Inconsistent use of terminology within the literature makes communication of imaging ndings relating to the anterior ethmoid cells
particularly challenging. In response to this, the
drainage pathway. Care must be taken to review imaging
in all planes, as the FSDP may appear narrowed in one
plane, but be displaced and widely patent when reviewed
in other planes (c)
2014 European Position Paper [9] advocates
anatomical description of the frontoethmoid
cell location relative to the FSDP (anterior, posterior, medial or lateral), rather than the use of
other classication systems. Whilst this gives a
general idea of the related anatomy, more detail
may be preferable in order to accurately dene
surgical procedures, educate trainees and report
outcomes. With this in mind, the International
Frontal Sinus Anatomy Classication (IFAC)
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a
SAC
SBC
ANC
FSDP
EB
def
SOEC
b
SBFC
SBC
EB
FSDP
Anterior
ethmoidal artery
SOEC
c
FSC
SAC
ANC
SOEC
ANC
FSDP
Fig. 14.10 Examples from the International Frontal
Sinus Anatomy Classication (IFAC) [10]. This classication system separates the anterior ethmoid cells that surround the FSDP into an anterior group (which push the
FSDP medially, posteriorly or posteromedially—highlighted in red), a posterior group (which push the FSDP
anteriorly—highlighted in green) and a medial group
(which push the FSDP laterally—highlighted in yellow).
The anterior group include the agger nasi cell (ANC),
supra agger cell (SAC) and the supra agger frontal cell
was published [10]. Some examples are
included below (Fig. 14.10a–f), the reader is
directed to the original paper for additional
detail.
The anterior ethmoidal artery, a branch of the
ophthalmic artery, is located by the presence of a
small notch at the superomedial orbital wall on
coronal imaging. It may travel along the ethmoid
(SAFC). The posterior group includes the suprabullar cell
(SBC), suprabullar frontal cell (SBFC) and supraorbital
ethmoid cell (SOEC). The medial group comprises frontal
septal cells (FSC). Images a–c show the relationship of
these cells to the FSDP. Images d–f are from the same
patient, showing the anatomical relationships of a large
supraorbital ethmoid cell, note should be made of the relatively exposed position of the anterior ethmoidal artery as
it traverses the cell
roof or, when there is a pneumatised cell extending above it, be suspended within the sinuses on
a bony or brous mesentery exposing it to injury
during endoscopic surgery (Fig. 14.11a–c).
Defects in the lamina papyracea, either traumatic
or developmental, are important to recognise as
orbital contents may prolapse into the ethmoid
sinuses (Fig.14.11d).
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A. S. McQueen and J. K. Dixon
a
Anterior
ethmoidalartery
*
c
Left anterior ethmoidal artery
exposed due to frontal sinus
pneumatisation above the
artery
*
b
d
Rightanterior ethmoidal
artery exposed within
anterior ethmoidal cell
Medial displacemento
the lamina papyracea
with prolapse of orbital
fat into the ethmoid
cells
Fig. 14.11 (a) The anterior ethmoidal artery is located by
the presence of a small notch at the superior aspect of the
lamina papyracea (asterisk), which is best appreciated on
coronal imaging. Where there is pneumatised sinus extending above the artery it becomes exposed, putting it at
increased risk of iatrogenic injury. Pneumatisation is com-
The Anterior Skull Base
The height of the anterior skull base relative to
the orbits is variable and a standardised method
for measurement has been described [12]. The
widely used Keros classication describes the
monly from a supraorbital ethmoid cell (SOEC) (b) but can
also be due to posterior pneumatisation of the frontal sinus
(c). As seen in this case, the two cell types cannot be differentiated on a single coronal image. (d) Medial displacement
or dehiscence of the lamina papyracea, either congenital or
relating to previous injury should be recognised
depth of the olfactory fossa (Fig.14.12a–d), with
a deeper fossa leaving the thin lateral lamella
exposed to injury. Anterior skull base asymmetry
or areas of bone dehiscence at the ethmoid roof
are important to communicate.
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