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Fig. 14.23 A 56-year-old female with unilateral nasal
obstruction and past history of inverted papilloma resection. Thin slice, 3D volume acquisition of post-contrast
T1 weighted, fat-suppressed MRI (left) reveals a mass lling the sphenoid sinuses and posterior left nasal cavity
(asterisk). The anteroposterior extent of the mass (dotted
Fig. 14.24 A 9-year-old girl with unilateral nasal
obstruction and facial pain. Contrast-enhanced MRI (left)
demonstrates an extensive enhancing mass centred on the
right masticator space and maxilla (asterisk). 18F-FDG
PET/CT (right) shows avid uptake within the mass—note
arrow) and inltration through the planum sphenoidale to
abut the dura (arrows) are delineated using isotropic
(equal resolution) sagittal and coronal reconstructions
from a single MRI sequence. Diagnosis=squamous cell
carcinoma
the physiological, lower uptake in the adjacent, benign
adenoid lymphoid tissue despite similar MRI enhancement (dotted arrow). PET/CT also revealed multifocal
skeletal lesions (red arrows). Diagnosis = metastatic
rhabdomyosarcoma
grade (adenoid cystic carcinoma) to intense
(sinonasal undifferentiated carcinoma, lymphoma). In addition, benign conditions such as
inverted papilloma can demonstrate moderate
FDG uptake; therefore, the specicity of PET-CT
to identify malignancy is limited. In the authors’
institution, PET-CT is reserved for specic neoplastic scenarios and interpreted in the context of
high-quality anatomic imaging, endoscopic and
biopsy ndings (Fig.14.24).
Catheter angiography plays an important role
in the scenario of a vascular tumour or malforma-
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A. S. McQueen and J. K. Dixon
Fig. 14.25 A 14-year-old male, unilateral nasal obstruction and epistaxis. MRI shows an avidly enhancing mass
at the right posterior choana with involvement of the pterygoid plates (yellow arrow). Digital subtraction angiography of the right internal maxillary artery shows immediate
tion in the nose and sinuses. Angiography of the
internal and external carotid arteries is the gold
standard for determining feeding vessel origin
and vascular outow and can be combined with
pre-operative arterial embolisation to reduce
perioperative bleeding (Fig.14.25).
Plain radiographs for sinonasal disease are
now largely obsolete and their use is not recommended [38, 39]. The sensitivity and specicity
are poor whilst the evolution of MDCT and
CBCT has largely obviated the benet of plain
radiography as easy-access, low-dose imaging.
arteriole lling within the lesion (dotted arrow) and
tumour blush (red arrow). Coil embolisation (dotted black
arrow) via micro-catheter was performed with subsequent
uneventful endoscopic resection. Diagnosis = juvenile
nasopharyngeal angiobroma
Future Developments inRhinology
Imaging
Evolution ofImage-Guided Surgery
(IGS) andIntra-operative Imaging
Image-guided surgery (IGS) for the sinuses and
skull base emerged in the late 1980s and is utilised in an expanding range of primary and revision surgical settings [31]. Advances in radiologic
imaging have facilitated increasingly accurate
and innovative IGS: in particular, high spatial
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Fig. 14.26 Image-guided FESS using MDCT for realtime navigation. Note the colour-coded display of sinus
and bony anatomy, providing virtual reality (VR) feed-
resolution CT (both MDCT and CBCT) and MRI
data creates detailed 3D volumes that can be registered with 2D endoscopic imaging with high
accuracy (Fig 14.26). As IGS use continues to
grow, progressively more personalised preoperative planning is feasible, desirable to the
surgeon and can be utilised in novel ways.
Displaying 3D imaging anatomy alongside realtime, operative appearances presents the surgeon
with a virtual reality (VR) of detailed diagnostic
information regarding key anatomic features and
patterns of obstruction to improve surgical efciency and reduce the risk of complication in
endoscopic sinus surgery (ESS) [40]. Recent
developments in VR include the fusion of MRI
and CT to combine soft tissue and bony detail to
assist tumour delineation and surgical decisionmaking in sinonasal tumour resection; multimodality IGS better harnesses the value of diagnostic
imaging in this setting. The more recent innovation of augmented reality (AR) involves the direct
overlay of pre-operative imaging volumes onto
endoscopic data to fundamentally alter the visual
display and integrated surgical experience. The
benets and potential drawbacks of AR ESS are
beyond the scope of this chapter, but there is evi-
back to the operating surgeon. Images courtesy of
Brainlab AG, Olof-Palme-Straße 9, 81829 Munich,
Germany
dence of a positive effect on clinical outcomes,
training experience and surgical opinions [41,
42]. The evolution of IGS will continue to build
on the strengths of modern radiology with
increasingly novel methods of presenting
personalised imaging information, to the benet
of both the surgeon and the patient.
A discrete application of IGS is the acquisition of real-time radiology during sinonasal procedures—intra-operative imaging (IoI). The key
benet of IoI is to present imaging anatomy
obtained during the surgical procedure rather
than from a pre-operative time point, demonstrating temporal and operative changes to the surgeon in real time. IoI use in selected sinonasal
procedures is endorsed [43], but practical issues
with imaging hardware—particularly time constraints and safety (e.g. MRI)—have limited
large-scale use. More recently, technical development of smaller imaging systems with faster
acquisition times makes wider IoI use increasingly feasible. As an example, the practical ease
of cone beam imaging (either with a CBCT scanner or C arm uoroscopy) within the operating
room environment has been shown to be feasible
for complex or revision ESS and skull base sur-
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A. S. McQueen and J. K. Dixon
gery [44, 45]. Outside of sinonasal surgery, the
safe and effective use of intra-procedural cone
beam anatomic imaging in maxillofacial [46] and
spinal surgery [47] is further evidence to support
the wider use of sinonasal IoI in the future.
Emerging Applications ofArticial
Intelligence (AI)
Of all the technical developments in modern
imaging considered in this chapter, the integration of articial intelligence (AI) into sinonasal
radiology may lead to the greatest changes in
clinical practice. The potential for AI to support
human image analysis and decision-making
within otorhinolaryngology is the subject of
extensive research with new applications and
clinical tools emerging at a rapid pace [48].
Radiology AI is multifaceted and fast moving;
however, automated detection and interpretation
of imaging ndings are of particular relevance to
rhinology. Machine Learning (ML) and Deep
Learning (DL) via convolutional neural networks
(CNN) are the principal techniques being studied
and require large volumes of dened data to train
and validate accuracy. The anatomy of the nose
and sinuses and the modalities used in rhinology
imaging provide an attractive AI environment:
detailed, standardised imaging that can be
labelled, segmented and categorised to provide
the necessary substrate for ML and DL
applications.
Several authors have recently described a role
for AI in the automated detection of important
anatomic ndings on paranasal sinus
MDCT. Using 675 coronal MDCT images, a
CNN (Google Inception-V3) was trained to recognise the position of the anterior ethmoid artery.
This DL technique then correctly identied the
artery with 82.7% accuracy on a set of validation
cases [49]. The presence of middle turbinate
pneumatisation was studied with the same CNN
and demonstrated 81% accuracy for correct identication of concha bullosa on MDCT [50]. In
addition to anatomic variant detection, accurate
identication of disease patterns with AI is
increasingly reported—in one study, osteomeatal
complex occlusion on MDCT was accurately
identied using a CNN and subtype of DL called
Transfer Learning [51]. The area under the curve
of 0.87 demonstrated good to excellent classication of this single nding; however, the authors
rightly noted the limitations of AI in this setting;
in particular, the results were based on single 2D
image interpretation rather than 3D volume (due
to current limits of CNN application) and therefore do not directly compare to human analysis in
clinical radiology practice. What these early
studies do indicate is the strong potential for AI
to provide an automated support tool for the
reporting radiologist, especially within the template/checklist framework of sinonasal MDCT
and CBCT reporting.
The use of AI to characterise pathological
imaging ndings, assist management planning
and even detect prognostic features is referred to
as Radiomics. Sinonasal neoplasms present a set
of clinical challenges (benign vs malignant, optimal management, surgical vs non-surgical therapy) where radiomics might add signicant
clinical value and this area has been the subject of
several recent studies. An example is the detection of squamous cell carcinoma development in
patients with inverted papilloma, where analysis
of anatomic imaging is challenging. In this setting, radiomic MR image interpretation (texture
analysis) produced a similar level of performance
to an experienced head-and-neck radiologist in a
study of 46 patients [52]. The imaging information used by the ML algorithm in this study goes
beyond the human eye, comparing multiple
intrinsic quantitative features and identifying patterns to characterise malignant risk. Using imaging from patients with squamous cell carcinoma,
characterisation of radiomic MRI features has
recently been studied to identify predictors of
treatment success and failure [53]. Using multiparametric MR image interrogation (which
included diffusion and perfusion parameters,
lesion morphology and intratumour image analysis), the ML-based prediction of local control and
recurrence was highly accurate, albeit in a small
patient group. The potential for radiomics to
improve clinical outcomes in patients with sinonasal disease is increasingly apparent and the
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future utility of AI to assist—and potentially
replace—human roles is both exciting and
controversial.
Key Learning Points
• CT (multidetector and cone beam) and MRI
are widely used in the nose and sinuses and
provide superb detail of bone and soft tissue
anatomy, respectively.
• To fully appreciate the complex 3D anatomy
of the nose and sinuses, images should routinely be reviewed in all three planes (axial,
coronal and sagittal).
• Standardised radiology reporting has perceived
benets and risks but will become more widely
used in the future, with the aim of increasing
clarity of reporting and reducing error.
• High-resolution imaging enables increasingly
accurate image-guided surgery (IGS) to
reduce operative time and complications, with
wider use of intra-operative imaging (IoI)
anticipated.
• There is an emerging role for articial intelligence (AI) in sinonasal radiology to support
human image analysis and assist patient
management.
Acknowledgement The authors would like to thank
Tony Hulbert from Hulbert Dental ICT for his advice and
expertise regarding cone beam CT.
References
1. Vaid S, Vaid N.Normal anatomy and anatomical variants of the paranasal sinuses on computed tomography. Neuroimaging Clin N Am. 2015;25:527–48.
2. Beale TJ, Madani G, Morley SJ. Imaging of the
paranasal sinuses and nasal cavity: normal anatomy
and clinically relevant anatomical variants. Semin
Ultrasound CT MRI. 2009;30(1):2–16.
3. Iida E, Anzai Y. Imaging of paranasal sinuses and
anterior skull base and relevant anatomic variations.
Radiol Clin North Am. 2017;55:31–52.
4. Shpilberg KA, Daniel SC, Doshi AH, Lawson W,
Som PM. CT of anatomic variants of the paranasal sinuses and nasal cavity: poor correlation with
radiologically signicant rhinosinusitis but importance in surgical planning. Am J Roentgenol.
2015;204:1255–60.
5. Vaid S, Vaid N, Rawat S, Ahuja AT. An imaging
checklist for pre-FESS CT: framing a surgically relevant report. Clin Radiol. 2011;66:459–70.
6. Anusha B, Baharudin A, Philip R, Harvinder S, Mohd
Shafe B. Anatomical variations of the sphenoid
sinus and its adjacent structures: a review of existing
literature. Surg Radiol Anat. 2014;36:419–27.
7. Daniels DL, Mafee MF, Smith MM, Smith TL,
Naidich TP, Brown WD, Bolger WE, Mark LP,
Ulmer JL, Hacein-Bay L, Strottman JM.The frontal
sinus drainage pathway and related structures. Am J
Neuroradiol. 2003;24(8):1618–27.
8. O’Brien WT, Hamelin S, Weitzel EK.The preoperative sinus CT: avoiding a “CLOSE” call with surgical
complications. Radiology. 2016;281(1):10–21.
9. Lund VJ, Stammberger H, Fokkens WJ, Beale
T, Bernal-Sprekelsen M, Eloy P, Georgalas C,
Gerstenberger C, Hellings PW, Herman P, Hosemann
WG, Jankowski R, Jones N, Jorissen M, Leunig A,
Onerci M, Rimmer J, Rombaux P, Simmen D, Tomazic
PV, Tschabitscher M, Welge-Luessen A. European
position paper on the anatomical terminology of the
internal nose and paranasal sinuses. Rhinol Suppl.
2014;24:1–34.
10. Wormald PJ, Hoseman W, Callejas C, Weber RK,
Kennedy DW, Citardi MJ, Senior BA, Smith TL,
Hwang PH, Orlandi RR, Kaschke O, Siow JK,
Scczygielski K, Goessler U, Khan M, BernalSprekelsen M, Kuehnel T, Psaltis A.The International
Frontal Sinus Anatomy Classication (IFAC) and
classication of the extent of endoscopic frontal
sinus surgery (EFSS). Int Forum Allergy Rhinol.
2016;XX:1–19.
11. Huang BY, Lloyd KM, DelGaudio JM, Jablonowski
E, Hudgins PA. Failed endoscopic sinus surgery:
spectrum of CT ndings in the frontal recess.
Radiographics. 2009;29:177–95.
12. Rudmik L, Smith TL.Evaluation of the ethmoid skull
base height prior to endoscopic sinus surgery: a preoperative CT evaluation technique. Int Forum Allergy
Rhinol. 2012;2:151–4.
13. Deutschmann MW, Yeung J, Bosch M, Lysack JT,
Kingstone M, Kilty SJ, Rudmik LR. Radiologic
reporting for paranasal sinus computed tomography: a
multi-institutional review for content and consistency.
Laryngoscope. 2013;123:1100–5.
14. European Society of Radiology. ESR paper on
structured reporting in radiology. Insights Imaging.
2018;9:1–7.
15. Mamlouk MD, Chang PC, Saket RR. Contextual
radiology reporting: a new approach to neuroradiology structured templates. Am J Neuroradiol.
2018;39(8):1406–14.
16. Johnson AJ, Chen MY, Shannon Swan J, Applegate
KE, Littenberg B.Cohort study of structured reporting compared with conventional dictation. Radiology.
2009;253:74–80.
17. Gunderman RB, McNeive LR.Is structured reporting
the answer? Radiology. 2014;273:7–9.
184
https://t.me/medicina_free
A. S. McQueen and J. K. Dixon
18. Kahn CE, Langlotz CP, Burnside ES, Channin DS,
Hovsepian DM, Rubin DL.Toward best practices in
radiology reporting. Radiology. 2009;252(3):852–6.
19. Schwartz LH, Panicek DM, Berk AR, Li Y, Hricak
H. Improving communication of diagnostic radiology ndings through structured reporting. Radiology.
2011;260:174–81.
20. Becker SS, O’Malley BB.Evaluation of sinus computed tomography scans: a collaborative approach
between radiology and otolaryngology. Curr Opin
Otolaryngol Head Neck Surg. 2013;21:69–73.
21. Heye T, Gysin V, Boll DT, Merkle EM. Structured
reporting: the voice of the customer in an ongoing
debate about the future of radiology reporting. Am J
Roentgenol. 2018;211:964–70.
22. Larson DB, Towbin AJ, Pryor RM, Donnelly
LF. Improving consistency in radiology reporting
through the use of department-wide standardized
structured reporting. Radiology. 2013;267(1):240–50.
23. Larson DB. Strategies for implementing a standardised structured radiology reporting program.
Radiographics. 2018;38:1705–16.
24. Trinh TW, Shinagare AB, Glazer DI, DiPiro PJ,
Mandell JC, Boland G, Khorasani R. Radiology
report template optimization at an academic medical
center. Am J Roentgenol. 2019;213:1108–014.
25. Huang BY, Senior BA, Castillo M. Current trends
in sinonasal imaging. Neuroimaging Clin N Am.
2015;25(4):507–25.
26. Flohr TG, Schaller S, Stierstorfer K, Bruder H,
Ohnesorge BM, etal. Multi-detector row CT systems
and image-reconstruction techniques. Radiology.
2005;235(3):756–73.
27. Reiss-Zimmermann M, Schulz T, Kahn T, Hofer
M.Imaging of the sinuses for functional sinus surgery
using navigational guidance. Laryngorhinootologie.
2012;91(3):160–6.
28. Nauer CB, Eichenberger A, Dubach P, Gralla J,
Caversaccio M. CT radiation dose for computerassisted endoscopic sinus surgery: dose survey and
determination of dose-reduction limits. AJNR Am J
Neuroradiol. 2009;30:617–22.
29. Schulz B, Beeres M, Bodelle R, Bauer R, Al-Butmeh
F, et al. Performance of iterative image reconstruction in CT of the paranasal sinuses: a phantom study.
AJNR Am J Neuroradiol. 2013;34(5):1072–6.
30. Hoxworth JM, Lal D, Fletcher GP, Patel AC, He M,
etal. Radiation dose reduction in paranasal sinus CT
using model-based iterative reconstruction. AJNR Am
J Neuroradiol. 2014;35(4):644–9.
31. Schmale IL, Vandelaar LJ, Luong AU, Citardi MJ,
Yao WC. Image-guided surgery and intraoperative
imaging in rhinology: clinical update and current
state of the art. Ear Nose Throat J. 2020; https://doi.
org/10.1177/0145561320928202.
32. Miracle AC, Mukherji SK.Conebeam CT of the head
and neck, part 1: physical principles. AJNR Am J
Neuroradiol. 2009;30(6):1088–95.
33. Nardi C, Talamonti C, Pallotta S, Saletti P, Calistri L,
etal. Head and neck effective dose and quantitative
assessment of image quality: a study to compare cone
beam CT and multislice spiral CT.Dentomaxillofac
Radiol. 2017;46:20170030.
34. Almashraqu AA, Ahmed EA, Mohamed NS,
Barngkgei IH, Elsherbini NA, et al. Evaluation
of different low-dose multidetector CT and cone
beam CT protocols in maxillary sinus imaging:
part I-an in vitro study. Dentomaxillofac Radiol.
2017;46:20160323i.
35. Veldhoen S, Schöllchen M, Hanken H, Precht C,
Henes FO, etal. Performance of cone-beam computed
tomography and multidetector computed tomography
in diagnostic imaging of the midface: a comparative study on Phantom and cadaver head scans. Eur
Radiol. 2016;27(2):790–800.
36. Pulickal GG, Navaratnam AV, Nguyen T, Dragan AD,
Dziedzic M, et al. Imaging sinonasal disease with
MRI: Providing insight over and above CT. Eur J
Radiol. 2018;102:157–68.
37. Ozturk K, Gawande R, Gencturk M, Boegel K,
Caicedo-Granados E, etal. Imaging features of sinonasal tumors on positron emission tomography and
magnetic resonance imaging including diffusion
weighted imaging: a pictorial review. Clin Imaging.
2018;51:217–28.
38. Royal College of Radiologists. iRefer guidelines:
making the best use of clinical radiology; 2017.
https://www.irefer.org.uk/. Accessed 02 Feb 2021.
39. Kirsch CFE, Bykowski J, Aulino JM, Berger
KL, Choudhri AF, et al. ACR appropriateness
criteria sinonasal disease. J Am Coll Radiol.
2017;14(11S):S550–9.
40. Dalgorf DM, Sacks R, Wormald PJ, Naidoo Y, Panizza
B, etal. Image-guided surgery inuences perioperative morbidity from endoscopic sinus surgery: a systematic review and meta-analysis. Otolaryngol Head
Neck Surg. 2013;149(1):17–29.
41. Linxweiler M, Pillong L, Kopanga D, Kühn JP,
Wagenpfeil S, et al. Augmented reality-enhanced
navigation in endoscopic sinus surgery: a prospective, randomized, controlled clinical trial. Laryngosc
Investig Otolaryngol. 2020;5:621–9.
42. Agbetoba A, Luong A, Siow JK, Senior B, Callejas
C, etal. Education utility of advanced 3-dimensional
virtual imaging in evaluating the anatomical conguration of the frontal recess. Int Forum Allergy Rhinol.
2017;7(2):143–8.
43. Intra-Operative Use of Computer Aided Surgery.
American Academy of Otolaryngology-Head and
Neck Surgery; 2011. http://www.entnet.org/Practice/
policyIntraOperative Surgery.cfm
44. Daly MJ, Siewerdsen JH, Moseley DJ, Jaffray DA,
Irish JC. Intraoperative cone-beam CT for guidance
of head and neck surgery: assessment of dose and
image quality using a C-arm prototype. Med Phys.
2006;33(10):3767–80.
14 Radiological Imaging inRhinology
https://t.me/medicina_free
185
45. Lee S, Gallia GL, Reh DD, Schafer S, Uneri A, etal.
Intraoperative C-arm cone-beam CT: quantitative
analysis of surgical performance in skull base surgery.
Laryngoscope. 2012;122(9):1925–32.
46. Assouline SL, Meyer C, Weber E, Chatelain B,
Barrabe A, etal. How useful is intraoperative cone
beam computed tomography in maxillofacial surgery? An overview of the current literature. Int J Oral
Maxillofac Surg. 2020;50(2):198–204.
47. Tonetti J, Boudissa M, Kerschbaumer G, Seurat
O. Role of 3D intraoperative imaging in orthopaedic and trauma surgery. Orthop Traumatol Surg Res.
2020;106(1S):S19–25.
48. Tama BA, Kim DH, Kim G, Kim SW, Lee S.Recent
advances in the application of articial intelligence in
otorhinolaryngology-head and neck surgery. Clin Exp
Otorhinolaryngol. 2020;13(4):326–39.
49. Huang J, Habib AR, Mendis D, Chong J, Smith M,
Duvnjak M, etal. An articial intelligence algorithm
that differentiates anterior ethmoidal artery location
on sinus computed tomography scans. J Laryngol
Otol. 2020;134(1):52–5.
50. Parmar P, Habib AR, Mendis D, Daniel A, Duvnjak
M, Ho J, et al. An articial intelligence algorithm
that identies middle turbinate pneumatisation (concha bullosa) on sinus computed tomography scans. J
Laryngol Otol. 2020;134(4):328–31.
51. Chowdhury NI, Smith TL, Chandra RK, Turner
JH.Automated classication of osteomeatal complex
inammation on CT using convolutional neural networks. Int Forum Allergy Rhinol. 2019;9(1):46–52.
52. Ramkumar S, Ranjbar S, Ning S, Lal D, Zwart CM,
etal. MRI-based texture analysis to differentiate sinonasal squamous cell carcinoma from inverted papilloma. Am J Neuroradiol. 2017;38:1019–25.
53. Fujima N, Shimizu Y, Yoshida D, Kano S, Mizumachi
T, et al. Machine-learning-based prediction of
treatment outcomes using MR imaging-derived
quantitative tumor information in patients with
sinonasal squamous cell carcinomas: a preliminary
study. Cancers. 2019;11:800. https://doi.org/10.3390/
cancers11060800.
Section III
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Paediatric Sinonasal Disorders
Congenital Sinonasal Disorders
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GraceCKhong andRaymondW.Clarke
15
Introduction
Babies are obligate nasal breathers and any
obstruction to nasal airow at birth will cause
severe hypoxaemia, only relieved when the baby
breathes through the mouth. Nasal obstruction in
the newborn is an emergency requiring urgent
referral and treatment [1].
Embryology oftheNose
andMidface
The skeletal structures of the midface develop by
fusion of the frontonasal prominence, the maxillary prominences and the mandibular prominences. Aberrant fusion of these processes can
give rise to orofacial clefting, of which the commonest varieties are cleft lip (CL) and cleft palate
(CP), often with some nasal involvement.
The nasal cavities and the paranasal sinuses
develop from the primitive foregut. Two epithelial elevations (nasal placodes) appear at about
the fourth intra-uterine week. They fuse to form
the lateral nasal walls, and the midline septum
extends dorsally to separate the nose into the two
nasal cavities, each closed behind by the ‘bucco-
nasal membrane’. A persistent bucco-nasal membrane presents as choanal atresia.
Partial or complete agenesis of the nose
(arhinia) is a rare neonatal emergency requiring
immediate airway support (a Guedel airway, followed in many cases by a tracheostomy) before
denitive repair is undertaken.
The developing nose is closely related to the
primitive forebrain, from which it becomes separated by the bony structures of the anterior skull
base, including the cribriform plate. The developing brain may herniate into the nasal cavity, giving rise to a meningocele or an encephalocele,
which can then present as a nasal mass.
Choanal Atresia
Choanal atresia (CA) is a developmental structural anomaly caused by failure of canalization of
the posterior nasal apertures (choanae). The incidence is 1in 5000 to 1in 8000 live births [2]. The
atretic plate may be bony (29%), membranous or
mixed (71%) and unilateral or bilateral (ratio
2:1), with the latter presenting as an airway emergency at birth [3, 4].
G. C Khong · R. W. Clarke (*)
Department of Ear, Nose and Throat, Alder Hey
Children’s NHS Foundation Trust, Liverpool, UK
e-mail: grace.khong@alderhey.nhs.uk; Raymond.
Clarke@alderhey.nhs.uk
© 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_15
Clinical Presentation
Unilateral CA is usually an isolated occurrence
and can present in older children. In contrast,
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G. C Khong and R. W. Clarke
bilateral CA presents in neonates and may be
associated with a series of linked congenital
defects, referred to as the CHARGE association.
Some or all of the following—Coloboma, Heart
anomalies, Atresia of the choanae, Renal anomalies, Genital hypoplasia, Ear anomalies—may
accompany choanal atresia, and babies should
always be examined and screened by a paediatrician. Some children with CHARGE features are
now known to have a specic genetic cause
(CHARGE syndrome).
As neonates are obligate nasal breathers, a
baby affected by bilateral CA will classically
have ‘cyclical cyanosis’ due to hypoxaemia
except during mouth breathing, as occurs when
the baby cries. Hence, it becomes almost impossible to feed the child. If the diagnosis is suspected, the midwife or neonatologist will try to
gently pass a small suction catheter from the
anterior nares into the nasopharynx. If it fails to
pass bilaterally, a diagnosis of choanal atresia is
suspected, and a good conrmatory test is to
place a cold stainless steel spatula or mirror just
under the baby’s anterior nares during a breath
cycle to test for misting and condensation (mirror
test) (Fig.15.1). It is important to note that neonatal rhinitis (see below) and obstruction of the
nose due to secretions is commoner than choanal
atresia, and in many suspected cases, no true atresia is found.
Immediate Management
The rst step in management is to secure a safe
airway. A Guedel tube in the oral cavity may sufce to enable safe transfer to a paediatric centre,
but endotracheal intubation may be required,
especially as many of these children have associated medical conditions.
Denitive treatment is surgical and should be
undertaken as quickly as the baby is stable to
facilitate feeding. Delay may compromise breast
feeding, and if immediate treatment is not possible, an oro-gastric feeding tube will be needed.
Investigations
Imaging (CT scanning) helps to conrm the diagnosis and plan denitive treatment. A little nasal
suction and a few drops of a decongestant such as
0.5% ephedrine help to clear the nares and make
for a more helpful image. Classical features of
choanal atresia on CT scan in addition to bony
and/or membranous obstruction are an air-uid
level in one or both nasal cavities on axial scans,
thickening of the vomer and medialization of the
pterygoid plates (Fig.15.2).
As mentioned earlier, a multidisciplinary
approach with paediatricians, cardiologists and
ophthalmologists is needed to check for any of
the features of a possible CHARGE association.
Further investigations such as ECHO and ultrasound of the renal tract are undertaken, as dictated by the ndings.
Fig. 15.1 Nasal misting
Surgical Management
There are now a variety of surgical reconstructive
techniques available. Older techniques relied on
an open trans-palatal approach but improved
modern endoscopes—especially the 120° endoscope that permits a highly detailed view of the
posterior nares on a monitor to facilitate transnasal surgery under direct vision—have made
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