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S. Taşar and R. Savaş
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2. Soboleski D, Theriault C, Acker A, Dagnone V, Manson D.Unnecessary irradiation to nonthoracic structures during pediatric chest radiography. Pediatr Radiol. 2006;36(1):22–5.
https://doi.org/10.1007/s00247- 005- 0016- y.
3. Ayşe E, Aslan T, Kiper N. ÇOCUK GÖĞÜS HASTALIKLARINDA TANI YÖNTEMLERİ.
4. Chest radiology: the essentials. Google Kitaplar. https://books.google.com.tr/books?id=RZBT
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q&f=false.
5. Moore ADA, Godwin JD, Dietrich PA, Verschakelen JA, Henderson WR.Swyer-James syndrome: CT ndings in eight patients. Am J Roentgenol. 1992;158(6):1211–5. www.ajron-
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6. Rambhia SH, D’Agostino CA, Noor A, Villani R, Naidich JJ, Pellerito JS.Thoracic ultrasound: technique, applications, and interpretation. In: Current problems in diagnostic radiology, vol. 46. Mosby Inc.; 2017. p.305–16.
7. Mayo JR, Aldrich J, Müller NL.Radiation exposure at chest CT: a statement of the eischner
society. Radiology. 2003;228(1):15–21.
8. Kim JE, Newman B. Evaluation of a radiation dose reduction strategy for pediatric chest
CT.Am J Roentgenol. 2010;194(5):1188–93.
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2004;233(2):515–22.
10. Lee CH, Goo JM, Lee HJ, Ye SJ, Park CM, Chun EJ, etal. Radiation dose modulation techniques in the multidetector CT era: from basics to practice. Radiographics. 2008;28(5):1451–9.
11. Pauls S, Aschoff AJ, Wahl J, Brambs HJ, Fleiter TR.Multi-detector row CT: is prospective
electrocardiographic triggering improving the detection of small pulmonary tumors? Acad
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Airways in the Pediatric Population. Radiology. 2003;229(3):641–50.
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14. Lee EY, Boiselle PM.Tracheobronchomalacia in infants and children: multidetector CT evaluation. Radiology. 2009;252(1):7–22.
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16. Yedururi S, Paul Guillerman R, Chung T, Braverman RM, Dishop MK, Giannoni CM,
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2008;28(3):1–75.
Fundamentals ofUpper Respiratory
Tract Endoscopy
SemihAk, NurayBayar Muluk, andSheng-PoHao
13.1 Introduction
The upper aerodigestive tract must be evaluated endoscopically for a correct diagnosis. Laryngoscopes, bronchoscopes, and esophagoscopes, both rigid and exible,
are among the tools at your disposal. The surgeon now has access to a wide range of
procedures for collecting data for an accurate diagnosis and, in some situations, for
implementing a therapeutic intervention, many of which can be done in an outpatient setting. A precise diagnosis, tumor staging, and the exclusion of concomitant
lesions are all possible by surgical endoscopy. The gold standard is to examine
thoroughly and biopsy a lesion while the patient is under general anesthesia. A sufcient biopsy specimen must be acquired regardless of the endoscopic approach
employed for a histologic diagnosis.
The purpose of an endoscopic examination of the equine upper airway is to
detect any anatomical or functional abnormalities in the nasal passages, nasal septum, turbinates, maxillary aperture, pharynx, guttural pouches (sometimes called
auditory tube diverticulum), larynx, or palate. Endoscopic examination of the nasal
and pharyngeal airways [1] requires a thorough understanding of normal nasopharyngeal anatomy.
13
S. Ak
Mehmet Akif İnan Training and Research Hospital, Şanlıurfa, Turkey
N. Bayar Muluk (*)
Department of Otorhinolaryngology, Faculty of Medicine, Kırıkkale University,
Kırıkkale, Turkey
S.-P. Hao
Department of Otorhinolaryngology, Shin Kong Wu Ho-Su Memorial Hospital, and Fu Jen
Catholic University, Taipei, Taiwan
© The Author(s), under exclusive license to Springer Nature
Switzerland AG 2024
H. Yüksel et al. (eds.), Pediatric Airway Diseases, Comprehensive ENT,
https://doi.org/10.1007/978-3-031-74853-0_13
177
178
S. Ak et al.
13.2 Nasal Diagnostic Procedures
A head and neck surgeon can view the nasal vault through a nasal speculum using
light sources that offer illumination and coaxial vision. Paying close attention to
mucosal color, edema, and discharge, as well as the effect of vasoconstriction, is
done both before and after nasal decongestion. The nasal septum, turbinates, and
vault can be partially seen using this method [2], but only under certain conditions.
Nose endoscopy is a procedure in which the nose and sinus passages are examined under direct, high-quality visual observation. As an objective diagnostic technique, otolaryngologists routinely use it to assess nasal mucosa, sinonasal
architecture, and nasal disease. A rigid endoscope or a exible beroptic endoscope
can be used to perform a nasal endoscopy. Flexible and inexible endoscopies are
generally well tolerated [3] when performed by trained professionals.
Rigid nasal endoscopes have different lens angles (0, 60, and 90°), making it
possible to see hidden features during conventional anterior rhinoscopy. To see
deeper structures or those off-axis from the nasal aperture [2], rigid nasal endoscopy
is an excellent tool for your disposal.
The rigid endoscope allows the endoscopist to see more clearly, take tissue samples, prevent epistaxis, and even do minor surgeries [4, 5]. The nasal cavity and
sinuses can be viewed in detail with the help of a rigid endoscope, which ranges in
diameter from 2.7 to 4mm and has angled tips (often between 0 and 70°) [3].
The advantages of nasal endoscopy for diagnostic purposes include enhanced
lighting, increased magnication, and pinpoint navigation to diseased regions. As a
result, doctors have a better chance of making a correct diagnosis. In one research,
nearly 40% of patients with routine exams on anterior rhinoscopy had nasal pathology revealed by rigid nasal endoscopy [6]. Patients with sinonasal symptoms often
benet from endoscopic evaluation before and after surgery and during medicinal
treatment [3].
13.2.1 Indications
Patients presenting to an otolaryngologist’s clinic should be evaluated with nasal
endoscopy because of its apparent involvement in diagnosing sinonasal illness.
• Intra-nasal examination: If you have an endoscopy, you can thoroughly check the
patients’ nasal passages and sinuses [3]
• The evaluation of the patient’s response to medical treatment (e.g., resolution of
polyps, purulent secretions, or mucosal edema and inammation after treatment
with topical nasal steroids, antibiotics, oral steroids, and antihistamines)
• Evaluate the patient’s response to unilateral disease (e.g., resolution of polyps,
purulent secretions, mucosal edema, and inammation after treatment with…
• Evaluation and biopsy of nasal masses or lesions
• Examination of the Nasopharynx for Lymphoid Hyperplasia, Eustachian Tube
Dysfunction, and Nasal Obstruction
13 Fundamentals ofUpper Respiratory Tract Endoscopy
• Diagnosis and Management of Epistaxis
• Diagnosis and Management of Cerebrospinal Fluid (CSF) Leak
• Diagnosis and Management of Hyposmia or Anosmia
• Evaluation of Cerebrospinal Fluid (CSF) Leak
• Foreign body evaluation and management in the nose.
179
13.2.2 Contraindications
There are no guaranteed risks associated with nasal endoscopy. However, some
patient groups should avoid it. It is essential to take extra precautions while performing nasal endoscopy on individuals using anticoagulants or having a history of
bleeding disorders. A vasovagal episode [3] can also occur in a nervous patient or a
patient with cardiovascular illness.
13.2.3 Anatomical Features
The septum is a bony and cartilaginous partition running along the middle of the
nose, creating two equal chambers on either side. The superior, middle, and inferior
conchas produce the superior, middle, and inferior meatus on the lateral nasal wall,
leading to the paranasal sinuses. The superior meatus is the drainage area for the
posterior ethmoid cells and the sphenoid sinus. The maxillary and frontal sinuses, as
well as the anterior ethmoid, drain through the middle meatus. The nasolacrimal
duct is exhausted through the inferior meatus [3].
The upper lateral cartilage, septum, nasal oor, and anterior head of the inferior
turbinate form the boundaries of the internal nasal valve. This is the most constricted part of the nasal passage in a leptorrhine [3].
13.2.4 Technical Considerations
Objective methods for diagnosing chronic rhinosinusitis (CRS) include nasal endoscopy and imaging [7]. Endoscopy provides a variety of preoperative and postoperative applications in the care of patients with sinonasal symptoms [3].
The presence of polyps, discharge, edema, scarring, or adhesions and crusting
are all factors that are taken into account by the Lund-Kennedy endoscopic grading
system to determine the severity of nasal and paranasal sinus pathology [8]. Bilateral
endoscopic staging is performed before diagnosis, surgery, and at suggested followup intervals of 3, 6, 12, 24, and 36months.
Between 0 and 20, the Lund-Kennedy scale measures how likely someone is to
take action. Absence (zero points), presence (one point), and presence (three points)
of polyps in the middle meatus are recorded. There are three levels of discharge
severity: nil (0), minimal (1), and severe (2). Edema, scarring, and crusting are each
evaluated as absence (0), mild (1), or severe (2). Interrater agreement studies
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S. Ak et al.
assessing the reliability of the Lund-Kennedy endoscopic scoring system reveal
that, in many cases, two independent observers agree on the examination ndings.
Adding nasal endoscopy to treating patients with CRS has led to more precise diagnoses [9]. Endoscopic ndings enhance the specicity, positive predictive value,
and negative predictive value of assessment for CRS when used with established
symptom criteria [7, 10] [11]. This development shows that the use of diagnostic
endoscopy may assist in lessening the requirement for computed tomography (CT)
and reduce expenditures and radiation exposure [3].
The authors of a best-practice article published by a triological society on nasal
endoscopy’s involvement in the diagnosis of CRS determined that the test alone has
low sensitivity but has repeatedly proven reasonable specicity in identifying CRS,
making it a helpful conrmatory test. High diagnosis accuracy of nasal endoscopy
was also identied in patients meeting both symptom criteria and favorable endoscopic results. In these cases [12], a diagnosis of CRS can be obtained without
resorting to more advanced imaging techniques.
In addition, a 2012 study conducted by Ferguson etal. indicated that nasal endoscopy has a sensitivity of 24% and a specicity of 100%, with mucopurulence only
present in patients with positive CRS on CT [13]. Staging of allergic fungal sinusitis
(AFS) has been shown to benet extensively using diagnostic endoscopy. Based on
nasal endoscopic results, Kupferberg-Kuhn classied AFS into four stages of the
disease [14]. Endoscopy is the gold standard for collecting tissue samples and cultures and provides an objective inspection measure. However, study results have
documented a greater than 90% correlation between endoscopically obtained cultures and maxillary sinus aspirates, making endoscopically guided cultures the current criterion standard. Historically, inferior meatal puncture was the diagnostic
method used to identify pathogens in sinusitis [15, 16].
Researchers found that 90% of nasal endoscopy specimens yielded cultures with
two or fewer bacterial isolates, while 55% lost a culture with a single isolate when
used for microbiologic diagnosis [17]. These ndings are more promising than those
from a nasopharyngeal swab. Endoscopy plays a crucial function in the postoperative
phase by allowing prompt debridement and monitoring for disease recurrence [3].
13.2.5 Technique
The nasal canals are numbed, and a decongestant is sprayed before the endoscope is
inserted. Antifog solution is applied to a 3mm 4mm 0, or 30° scopes before insertion into the nasal cavity [3].
Then, the examiner makes three independent passages with the scope within
each nostril (shown in the lms below) [5, 18, 19]. The nasal mucosa and nasal cav-
ity structures are inspected with each sweep. In particular, the examiner takes note
of the nasal mucosa’s color (pale vs. hyperemic), inammation or hypertrophy of
the mucosa, the presence of nasal polyps or secretions (purulent, thick, or thin), and
the presence of any visible anatomic abnormalities (e.g., a septal deviation or spur,
concha bullosa, or accessory ostia) [3].
13 Fundamentals ofUpper Respiratory Tract Endoscopy
181
13.2.5.1 First Pass
With the patient’s head exed, the scope is advanced along the oor of the nasal
cavity and into the nasopharynx. The nasolacrimal duct and the inferior turbinates,
where they drain, are inspected. The possibility of mucus or purulence draining into
the nasopharynx is considered as the scope is moved posteriorly into the nasopharynx. The nasopharynx, including the eustachian tube openings and the fossa of
Rosenmüller [3], is thoroughly inspected.
13.2.5.2 Second Pass
The second time around, the endoscope is inserted between the middle and inferior
turbinates to look at the fontanelles and the inferior part of the middle meatus for
supplementary maxillary Ostia. Next, the scope is advanced medially and posteriorly to the middle turbinate to investigate the sphenoethmoid depression lying
medial to the middle and superior turbinates. During this passage, the superior turbinate can be used to see the oval or slit-shaped ostia of the sphenoid sinus [3].
The infundibulum, uncinate, and ethmoid bulla can be seen by withdrawing the
scope and rotating it laterally under the middle turbinate. To insert the scope into the
middle meatus, you may need to provide gentle medial pressure to the middle turbinate [3].
13.2.5.3 Third Pass
The third attempt typically calls for a 30° endoscope or a change in head position.
The doctor can examine the olfactory cleft and detect any polyps or lesions. Due to
the septum’s curvature, it is usually only possible to thoroughly explore one side of
the nose at a time [3].
13.2.6 Problems During theProcedure
In most cases, a rigid nasal endoscopy can be performed with minimal danger to the
patient. Possible side effects of the surgery include sensitivity to the local anesthetic or
decongestant, pain, discomfort, epistaxis, and vasovagal episodes. It is essential to conrm that the patient has no known allergies to the topical drugs before using them [3].
It is essential to exercise caution since nasal hemorrhage related to mucosal
trauma can occur, especially in individuals at a higher risk for bleeding (such as
those with a personal or familial history of bleeding disorders or who are presently
using anticoagulants). Nasal biopsies taken from these patients also risk causing
severe bleeding [3].
13.3 Flexible Laryngoscopy
The nasal cavity, sinuses, pharynx, and larynx can all be viewed using exible
laryngoscopy, which is becoming increasingly popular. The method requires a relatively modest diameter exible endoscope and can be carried out in a doctor’s ofce.
182
The nasal cavity is numbed and decongested beforehand for better visibility and
comfort during the operation. In the technique, the examiner threads the end of the
scope through the nasal opening down the oor of the nasal cavity. The examiner
can see the inside of the nasal cavity to check for growths or lesions when the scope
is inserted further. Direct visibility of the whole pharynx and larynx [2] is achieved
by directing the scope inferiorly and advancing it gently as it nears the nasopharynx.
The beroptic telescope can be bent and swiveled in any number of directions,
making it ideal for gaining insight into otherwise inaccessible spaces. However,
exible endoscopy is more challenging because it requires two hands to manipulate
the equipment. Digital exible endoscopes [3] have addressed the historical limitation of exible endoscopy: poor visibility.
S. Ak et al.
13.4 Direct Laryngoscopy
One of the benets of direct laryngoscopy is that it can be used for diagnosis and
treatment. General anesthesia is a subset of intubated anesthesia. The therapy provides a plain view of the pharynx and the larynx and permits the surgeon to do
biopsies and remove tiny lesions. Simultaneously, the surgeon can palpate the oral
cavity, oropharynx, and hypopharynx, which are difcult to palpate in a conscious
patient [2].
The laryngoscope can be placed on a Mayo stand attached to the table (for handsfree use), and a microscope can be brought into focus to provide a more detailed
view of the glottis and subglottis. Small lesions or topological anomalies can be
better described and, if so desired, eliminated with a microscopic direct laryngoscopy. Vocal cord polyps, leukoplakia, intubation granulomas, contact ulcers, webs,
nodules, hematomas, and papillomatosis are all lesions that can be diagnosed with
a direct laryngoscopy. Furthermore, technological advancements make microlaryngoscopic examination of the vocal cords and CO2 laser ablation or excision of
small malignant tumors [2] possible.
13.5 Video Laryngoscopy
Direct laryngoscopy is different from the indirect laryngoscopy used in the clinic.
Transnasal or transoral insertion of a beroptic or digital laryngoscope allows for
vision of the larynx [20–22]. The movies below [20] show the distinction between
direct and indirect laryngoscopy.
Images captured during video laryngoscopy can be viewed in real-time on a
monitor by the doctor, patient, and other observers or saved for later review.
Displaying images at a larger size on the screen enables a thorough inspection of the
larynx. Fiberoptic intubation is predicated on video laryngoscopy [20].
Fiberoptic intubation includes threading an endotracheal (ET) tube over the shaft
of a exible beroptic scope. The patient’s mouth or nose is used to insert the scope
into the pharynx, and then the scope is advanced past the vocal folds and into the
13 Fundamentals ofUpper Respiratory Tract Endoscopy
183
trachea. The ET tube is moved across the ber optic cable into the patient’s airway
after visual conrmation of tracheal rings and carina. As soon as the tube is in position, the scope can be taken out, and the patient can begin to get ventilation [20].
The endoscopist will typically look via the scope’s eyepiece as they execute a
beroptic intubation. Hooking it up to a screen would be best to get the most out of
the area. Showing the process to others in the room is a great learning tool [23, 24].
Video laryngoscopy is also utilized with stiff transoral laryngoscopy. Rigid laryngoscopes with built-in digital cameras are becoming increasingly common, with famous
examples being the Airtraq laryngoscope (Prodol Meditec, Spain), the GlideScope
(Verathon, Bothell, WA), and the Pentax-AWS (Pentax, Tokyo, Japan). Video laryngoscopy using a rigid laryngoscope, such as the GlideScope, has been found to provide
a better image of the larynx than traditional laryngoscopy alone [25, 26].
13.5.1 Indications
Fiberoptic intubation can be performed on any patient who ts the intubation
requirements. However, most doctors save beroptic intubation for patients with a
challenging airway due to the specialized equipment required. The following conditions and patient types are more likely to have an unstable airway [27–30]:
• Micrognathia
• Mandibular fracture
• Partially obstructing laryngeal lesions such as papilloma or supraglottis
• A necessity for awake intubation
• Cervical spine injuries or cervical instability
• Rheumatoid arthritis (or patients unable to extend the neck)
• A history of head and neck radiation
• Trismus
• Craniofacial abnormalities
In January 2019, recommendations for intubation and extubation in the intensive
care unit (ICU) were issued by the French Society of Anesthesia and Intensive Care
Medicine (SFAR) and the French-Speaking Intensive Care Society (SRLF) [31].
For tracheal intubation guidance in patients with COVID-19, video laryngoscopy has been argued to be better than direct laryngoscopy [32, 33].
13.5.2 Contraindications
Airway (Cancer) (Highly Obstructive Pulmonary Disease (HNPPD) is a disease in
which the lungs become obstructed with cancerous tissue). Patients with laryngeal
trauma, especially those with a possible cricotracheal separation, are likewise advised
against using it. In patients with craniofacial trauma actively bleeding into the oropharynx, beroptic intubation is relatively contraindicated and may be dangerous [20].
184
S. Ak et al.
13.5.3 Outcomes
Blair etal. used medium-delity human simulators to simulate challenging airway
scenarios (cervical spine immobilization and trismus) and found that video laryngoscopy signicantly improved glottic exposure compared with direct laryngoscopy (97% Cormack-Lehane grade I or II vs. 51%) [34].
Lewis etal. conducted a Cochrane review comparing video laryngoscopy and
direct laryngoscopy for adult tracheal intubation. They found that video laryngoscopy has several advantages over direct laryngoscopy, including a better glottic
view and a decreased risk of laryngeal/airway trauma, especially in patients with a
difcult airway [35]. Lowering the incidence of complication during a video bronchoscopy (bronchoscopy) (20%) and lowering the incidence of complication during
a video bronchoscopy (20%).
Another Cochrane review comparing the two methods in children (excluding
neonates) found that intubation took longer and intubation failure was more common when using video laryngoscopy compared to direct laryngoscopy. However,
the quality of the evidence could have been better [36]. No rm conclusions could
be drawn regarding the deleterious hemodynamic responses and other adverse
effects of intubation in this cohort or whether video laryngoscopy may lead to an
enhanced view of the vocal cords [20].
Video laryngoscopy did not improve intubation success rates over direct laryngoscopy in emergency and critically ill patients, according to a comprehensive
study and meta-analysis by Jiang etal. [37]
13.5.4 Equipment
Equipment required for video laryngoscopy includes the following [20]:
• Fiberoptic bronchoscope with a light source
• Camera with the monitor if intubation is to be projected to the screen
• Lidocaine 4%
• Nasal trumpets, 28 and 36 French
• Glycopyrrolate 0.2mg (to be administered intravenously (IV) before the start of
the procedure)
• Endotracheal (ET) tubes (see Treatment for additional information)
• Warmed saline
• Syringe, 12mL
• Oral airway
• Carbon dioxide detector
• Antifog solution or an alcohol pad
• Suction tubing
• Oxygen with cannula
13 Fundamentals ofUpper Respiratory Tract Endoscopy
185
13.5.5 Approach Considerations
Choosing the right endotracheal (ET) tube is crucial. The tube must snugly t over
the ber optic scope. The ET tube’s internal diameter should be 3mm more signicant than the scope’s [38]. A signicant distance between the scope and the tube can
make threading the tube over the beroptic shaft difcult and increase the risk of the
tube being entangled in the laryngeal tissues [38]. It is crucial to utilize an ET tube
that is small enough to t through the patient’s nasal cavity if nasal intubation is to
be conducted. A tube size of 7.0 or smaller is recommended for big males. When the
patient is awake during intubation, the most painful part of the process is moving the
tube through the nasal channel; therefore, getting the size right is crucial [20].
Fiberoptic intubation can be performed with the help of specialized ET tubes.
Standard nasal anatomy is accommodated with a prefabricated Ring–Adair–Elwyn
(RAE) tube (Covidien-Nellcor, Boulder, CO). To prevent damaging the beroptic
channels of the bronchoscope, it is recommended to soak the nasal RAE tube in
warm saline for 5min before intubation [20].
Intubation with a Flexi-Tip tube is another option. This tube makes intubation
and insertion of a bronchoscope into the airway much more straightforward than
with a traditional line. The arytenoid cartilage is less likely to become trapped on
the exible tip, which points toward the lumen’s center [39]. If the bronchoscope’s
tip mists over, touching the patient’s mucosal surface will clear it immediately. To
clean the tip, you could also ask the patient to swallow [20].
If the surgery needs to be done while the patient is awake, a thorough explanation
of what will happen and why is essential for the patient’s cooperation.
The arytenoids are a potential snare for the ET tube if the beroptic scope has
difculty passing through the vocal folds and into the airway. Repeat steps 20 and
21 with the ET tube retracted 1–2cm and rotated 90 or 180°.
To facilitate movement, the bronchoscope should be held taut at all times by the
bronchoscopist.
The larynx can be better seen if the patient moves their head or jaw forward [20].
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2. Jacobson AS.Urken ML, Teng MS.ACS surgery: principles and practice. Head and neck diagnostic procedures. Medscape. https://www.medscape.com/viewarticle/521712_7. Accessed 3
June 2023.
3. Mallen JR.Nasal endoscopy. In: Meyers AD, editor. Medscape. 2021. https://emedicine.med-
scape.com/article/1890999- overview. Accessed 3 June 2023.
4. Stammberger H.Functional endoscopic sinus surgery. Philadelphia: BC Decker; 1991.
5. Kennedy DW, Zinreich SJ, Rosenbaum AE, Johns ME.Functional endoscopic sinus surgery.
Theory and diagnostic evaluation. Arch Otolaryngol. 1985;111(9):576–82.
6. Levine HL.The ofce diagnosis of nasal and sinus disorders using rigid nasal endoscopy.
Otolaryngol Head Neck Surg. 1990;102(4):370–3.