Ebook Office-Based rhinology: Principles and techniques (Part 1)

Office-Based Rhinology
Principles and Techniques



Office-Based Rhinology
Principles and Techniques

Zara M. Patel, MD
Sarah K. Wise, MD, MSCR
John M. DelGaudio, MD, FACS
Division of Rhinology
Department of Otolaryngology-Head and Neck Surgery
Emory University of School of Medicine


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NOTICE TO THE READER
Care has been taken to confirm the accuracy of the indications, procedures, drug dosages, and diagnosis and
remediation protocols presented in this book and to ensure that they conform to the practices of the general medical and health services communities. However, the authors, editors, and publisher are not responsible for errors
or omissions or for any consequences from application of the information in this book and make no warranty,
expressed or implied, with respect to the currency, completeness, or accuracy of the contents of the publication.
The diagnostic and remediation protocols and the medications described do not necessarily have specific approval
by the Food and Drug administration for use in the disorders and/or diseases and dosages for which they are
recommended. Application of this information in a particular situation remains the professional responsibility of
the practitioner. Because standards of practice and usage change, it is the responsibility of the practitioner to keep
abreast of revised recommendations, dosages, and procedures.
Every attempt has been made to contact the copyright holders for material originally printed in another source. If any
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Library of Congress Cataloging-in-Publication Data
Office-based rhinology : principles and techniques / Zara M. Patel, co-editor, Sarah K. Wise, co-editor, John M.
DelGaudio, co-editor.
p. ; cm.
Includes bibliographical references and index.
ISBN-13: 978-1-59756-475-5 (alk. paper)
ISBN-10: 1-59756-475-3 (alk. paper)
I. Patel, Zara M. II. Wise, Sarah K. III. DelGaudio, John M.
[DNLM: 1. Nose Diseases — surgery. 2. Ambulatory Surgical Procedures — methods. 3. Nasal Surgical
Procedures — methods. 4. Nose--surgery. WV 300]
617.5'23 — dc23

2012042898


Contents
Introductionvii

Contributorsix

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15

History of Nasal Endoscopy

4

Endoscopic Anatomy for Office-Based Rhinology Procedures

5

Radiology of the Nose and Paranasal Sinuses

15

Room Setup and Equipment for Office Procedures

37

Patient Selection and Informed Consent for Office-Based Procedures

45

Nasal and Sinus Anesthesia for Office Procedures

49

Basic Nasal Endoscopy and Biopsy

61

In-Office Treatment of Post-Endoscopic Sinus Surgery Issues

67

Office-Based Inferior Turbinate Reduction

77

Office-Based Management of Septal Pathologies

89

Office-Based Nasal Polypectomy

101

Office-Based Management of Mucoceles

109

Epistaxis:  Office-Based Management

117

Nasal Fractures:  Closed Reduction in the Office Setting

129

Office-Based Evaluation and Treatment of Epiphora

137

Index145



Introduction
As otolaryngology has moved toward minimally invasive procedures in every subspecialty, there has been a parallel trend to
perform these procedures in the office setting,
when possible.
Physicians and patients alike can derive
benefits from moving procedures from the hospital operating room to the office exam room.
Physicians have more flexibility in scheduling,
delays associated with staff shift changes and

equipment turnover are eliminated, time can
be used more efficiently, and more patients
can be seen. Patients are more comfortable in
a familiar environment, require less time away
from their regular schedules, have decreased
anesthesia requirements, are not exposed to
hospital acquired infectious organisms, and
often have a lower insurance copay for officebased procedures.
In this text, we cover the foundation of
knowledge a surgeon must have to prepare for

office-based procedures, including anatomy,
radiology, and basic endoscopic skills. We
review the basic preparatory steps involved
such as proper patient selection, room setup,
and local anesthetic techniques, and then present multiple rhinologic procedures that can be
performed in the office setting.
We have asked expert rhinologists across
the subspecialty to share their techniques in
this text, and we thank them for their excellent contributions. We have also compiled a
DVD of selected surgical procedures to help
the reader obtain a more complete and thorough understanding of these procedures.
We hope this book will educate surgeons
at all stages of their career, whether otolaryngology residents or those who have been
practicing for many years, and allow them to
develop a new and fulfilling aspect of their
practice as otolaryngologists.
Zara M. Patel
Sarah K. Wise
John M. DelGaudio

Department of Otolaryngology—
  Head and Neck Surgery
Emory University School of Medicine



Contributors
Robert T. Adelson, MD
Department of Otolaryngology-Head and
Neck Surgery
University of Pennsylvania School of Medicine
Philadelphia, Pennsylvania
Chapter 8
Kristen Lloyd Baugnon, MD
Department of Radiology
Emory University School of Medicine
Atlanta, Georgia
Chapter 3
John M. DelGaudio, MD, FACS
Division of Rhinology
Department of Otolaryngology-Head and
Neck Surgery
Emory University of School of Medicine
Atlanta, Georgia
Chapters 1, 2, 9, 11, 12, and 15
Praveen Duggal, MD
Department of Otolaryngology-Head and
Neck Surgery
Emory University School of Medicine
Atlanta, Georgia

Chapter 9
Richard J. Harvey, MD
Australian School of Advanced Medicine
Macquarie University
Faculty of Medicine
University of New South Wales
Sydney, Australia
Chapter 6
Oswaldo A. Henriquez, MD
Department of Otolaryngology-Head and
Neck Surgery

Emory University School of Medicine
Atlanta, Georgia
Chapter 11
Elizabeth K. Hoddeson, MD
Department of Otolaryngology-Head and
Neck Surgery
Emory University School of Medicine
Atlanta, Georgia
Chapter 1
Peter H. Hwang, MD
Department of Otolaryngology-Head and
Neck Surgery
Stanford University School of Medicine
Stanford, California
Chapter 10
H. Joon Kim, MD
Department of Ophthalmology
Emory University School of Medicine

Atlanta, Georgia
Chapter 15
Todd T. Kingdom, MD
Department of Otolaryngology-Head and
Neck Surgery
University of Colorado School of
Medicine
Denver, Colorado
Chapter 4
Adrienne Laury, MD
Department of Otolaryngology-Head and
Neck Surgery
Emory University School of Medicine
Atlanta, Georgia
Chapter 12


x  Office-Based Rhinology:  Principles and Techniques

Michael D. Lupa, MD
Department of Otolaryngology-Head and
Neck Surgery
Emory University School of Medicine
Atlanta, Georgia
Chapter 7

Anita Sethna, MD
Department of Otolaryngology-Head and
Neck Surgery
Emory University School of Medicine

Atlanta, Georgia
Chapter 14

James N. Palmer, MD
Department of Otolaryngology-Head and
Neck Surgery
University of Pennsylvania School of
Medicine
Philadelphia, Pennsylvania
Chapter 8

Kornkiat Snidvongs, MD
Department of Otolaryngology
Faculty of Medicine
Chulalongkorn University
Thailand
Chapter 6

Zara M. Patel, MD
Division of Rhinology
Department of Otolaryngology-Head and
Neck Surgery
Emory University of School of Medicine
Atlanta, Georgia
Chapters 5 and 7
Alkis James Psaltis, MD, PhD, FRACS
Department of Otolaryngology-Head and
Neck Surgery
Medical University of South Carolina
Charleston, South Carolina

Chapter 13
Vijay R. Ramakrishnan, MD
Department of Otolaryngology-Head and
Neck Surgery
University of Colorado School of Medicine
Denver, Colorado
Chapter 4
Rodney J. Schlosser, MD
Department of Otolaryngology-Head and
Neck Surgery
Medical University of South Carolina
Charleston, South Carolina
Chapter 13

Ethan Soudry, MD
Department of Otolaryngology-Head and
Neck Surgery
Stanford University School of Medicine
Stanford, California
Chapter 10
Reza Vaezeafshar, MD
Department of Otolaryngology-Head and
Neck Surgery
Stanford University School of Medicine
Stanford, California
Chapter 10
Craig Villari, MD
Department of Otolaryngology-Head and
Neck Surgery
Emory University School of Medicine

Atlanta, Georgia
Chapter 2
Sarah K. Wise, MD, MSCR
Division of Rhinology
Department of Otolaryngology-Head and
Neck Surgery
Emory University of School of Medicine
Atlanta, Georgia
Chapters 1, 2, and 5


To my wonderful parents, Marzban and Shireen Patel, my amazing sister, Cheherazade
Patel, and my incredible partner, André Rivard. Thank you all for your unwavering
love and support throughout the years, I owe so much to each of you.
—Zara M. Patel
To my husband and son, Justin and Bryson, who brighten every day while still keeping me
grounded. And to Ray and Ginny Miller, my remarkable parents, whose encouragement
and guidance have made me strong. I cannot thank you enough for your support.
—Sarah K. Wise
To my children, Rachel and Michael, the lights of my life. You make every day special.
And to my co-editors, Sarah and Zara. I could not ask for better partners and colleagues.
—John M. DelGaudio 



Chapter

1
History of Nasal Endoscopy
Elizabeth K. Hoddeson

Sarah K. Wise
John M. DelGaudio

History of the Endoscope
The history of minimally invasive surgery
extends back in time far beyond the current
century. Phillip Bozzini (1773–1809), a young
German obstetrician, first elucidated the prospect of minimally invasive surgery by essentially creating the foundation upon which the
principles of modern endoscopy originated;
he invented an instrument, the Lichtleiter,
which was a tool that could be introduced into
the body to solve the problem of inadequate
illumination during physical examination.1
However, he never tested his invention on a
human patient, and during his short lifetime
his device never gained widespread acceptance.1 Antoine Jean Desormeaux (1815–
1894) of France is credited as the “father of
endoscopy,” as he was the first to apply the
lichtleiter in patient care.2 He utilized a system of mirrors, lenses, and flames burning
alcohol and turpentine to provide illumination for urological procedures.2 He presented
the term “endoscope” at the Academy in Paris
in 1865.2 Thomas Edison’s landmark invention, the electric light bulb, was first utilized

in an instrument created to provide surgical
illumination for urological procedures by
Maximilian Nitze (1848–1906), the “father
or urology,” who also is credited with taking
the first endoscopic photographs.3,4 The German urologist was credited with two major
contributions: magnifying the image through
lenses and illuminating the organs by using an

internal rather than an external light.3
The turn of the century showed sweeping advances in the implementation of these
pioneering principles for surgical procedures.
In 1910, Hans Christian Jacobaeus (1879–
1937) described his original procedure, the
“laparathorakoskopie,” in addition to performing the first thoracoscopy in the same
year.5 Also in 1910, Victor Darwin Lespinasse (1878–1946), in spite of being a urologist from Chicago and not a neurosurgeon,
performed the first intraventricular endoscopy
and coagulation of the choroid plexus for the
treatment of hydrocephalus in two children.3
Laparascopy became much more functional with the contribution of Otto Goetze,
a diagnostic radiologist of Germany. He
invented a needle that could be used to create
a pneumoperitoneum, and had the foresight


2  Office-Based Rhinology:  Principles and Techniques

to describe its potential applications to facilitate minimally invasive surgery.6 In its early
stages, the pneumoperitoneum was not without serious complications; Raoul Palmer, a
gynecologist, stressed the importance of the
Trendelenburg position to allow the insufflated
air to fill the pelvis, rather than compressing
the chest cavity, and stressed the need for continuous monitoring of abdominal pressure to
facilitate early detection of complications.6
The genius and creativity of many men
further contributed to the principles of modern endoscopy. In 1929 Heinz Kalk invented a
135-degree lens system as well as an approach
to the peritoneum utilizing two trocars. He
was the first to use laparoscopy to diagnose

liver and gallbladder disease.6 In the era of
World War II, many people suffered the ravages of Mycobacterium tuberculosis; Janos Veress saw the need for better treatments, and
invented the spring-loaded needle in 1938
with the purpose of draining air or fluid from
body cavities, although he did not ever suggest
its use in laparoscopy.6 Harold H. Hopkins, a
mathematician and physicist, is credited with
the development of the zoom lens system
(1948), the rod-lens system, and fiberoptics
(1960).3 His inventions provided greater light
transmission, a wider view, improved image
quality, and permitted a smaller diameter lens.
Modern endoscopic instrumentation was rapidly materializing.
Despite the amazing medical potential of
the inventions by these revolutionary physicians, all of their advances were met with a
certain level of resistance. In 1966 Kurt Semm
invented the automatic insufflator.6 He utilized
his improved visualization to attempt an appendectomy during a routine laparoscopic gynecological exam.6 He was almost removed from the
German Society of Physicians for his unorthodox medical decision.6 The first successful laparoscopic cholecystectomy was performed on a
human in 1987 by Phillip Mouret.7

One of the major advantages acknowledged for endoscopic procedures is their
minimally invasive nature, which decreases
postoperative discomfort and speeds recovery
time. However, the mini-laparotomy incision for laparoscopic surgery was not even
described until 1971 by H.M. Hasson.6
The increasing acceptance of endoscopic
surgery as a standard of patient care was exhibited in 1981, when the American College of
Obstetrics and Gynecology instituted training in laparoscopic surgery as an integral part
of each of its residency training programs.8

Since that time, minimally invasive surgical techniques have emerged as the standard
and preferred techniques in general, urologic,
orthopedic, and otolaryngologic surgical fields.

History of Endoscopy of the
Nose and Paranasal Sinuses
In 1901 Hirschmann, a German otolaryngologist, used a modified cystoscope to examine the maxillary sinuses, and is consequently
credited as the pioneer of endoscopic paranasal sinus surgery.3,9 However, reports by Spiess
detail routine use of anterior rhinoscopy since
1868, albeit limited by extreme difficulty in
exploring the different meatuses and cavities
of the sinonasal region.10 Early endoscopic
diagnostic interest focused on the Eustachian
tube orifice and maxillary sinus antrum, but
the techniques failed to gain popular acceptance, often looked upon as superfluous,
providing results that were more simply and
equally obtained using more direct means.3,10
In 1902, Reichert performed the first sinus
surgery on a maxillary sinus via an oroantral
fistula as well as the first successful ethmoid
surgery by removing the middle turbinate, but
technical challenges limited widespread acceptance of the technique.10–12


History of Nasal Endoscopy  3

After Hopkins’ revolutionary improvements to the optical components of endoscopes, which resulted in enhanced light
delivery and superior optical quality, the
techniques were extended to investigate all
paranasal sinus cavities, with the goals of

reducing unnecessary and unnecessarily invasive surgery.3,10,11 Walter Messerklinger was
able to use these endoscopes, both zero and
30-degree, to study sinonasal anatomy and
mucociliary clearance in cadavers and thereby
produce his landmark book on sinonasal
endoscopic anatomy and diagnosis.10,11
Early applications of endoscopic techniques to the paranasal sinuses were hindered
by technical feasibility. Adequate instrumentation had to be developed to facilitate even
exploring the possibilities of these revolutionary techniques. Upon request, Karl Storz
designed and built endoscopes with 0, 30, 70,
90, and 120 degrees of deflection to facilitate
diagnosis and operative therapy.10 The first
instruments used in sinus surgery were orthopedic grasping instruments designed for cartilage removal, which were modified by Carl
Reiner from Vienna such that they could be
inserted into the nose parallel to the endoscope shaft.10,11 Following these postsurgical
patients endoscopically in the office permitted these surgeon pioneers to recognize the
detrimental effects of stripping mucosa and
leaving exposed bone on the healing process,
and finer nasal instruments designed to cut
through bone and mucosa were developed.10
Functional endoscopic sinus surgery
(FESS), was coined by David Kennedy to
stress the importance of preserving mucosa
and mucociliary drainage pathways during
surgical intervention.3 David Kennedy, Heinz
Stammberger, and Wolfgang Draf are some
of the otolarynologists who popularized these
techniques, and ultimately helped change the
standard of care for management of paranasal
sinus pathology.3

Prior to the popularization of FESS,
the majority of ethmoid procedures were
performed via external incisions or with a
headlight intranasally, but more often surgery
was only directed at the maxillary and frontal sinuses.11,14 The operating microscope was
suggested as a means of performing ethmoidectomies; however, despite providing a magnified image, its utility was limited as the small
nasal aperture precludes a consistent binocular view.11 The endoscope provides a magnified view in addition to deflected angles of
view, allowing surgeons to overcome previous
impediments to addressing areas not directly
within the line of sight.11
Sinonasal endoscopy and FESS have
revolutionized the field of rhinology, altering our understanding of both anatomy and
physiology of the paranasal sinuses in addition
to changing our medical and surgical management of paranasal sinus pathology. Due to its
portability, the endoscope has become an
invaluable tool in the office setting for diagnosis and postoperative care, and as outlined
in this text, has allowed increasingly complex
interventions to take place in the office setting
as well.11

References
1.  Rathert P, Lutzeyer W, Goddwin WE. Philipp
Bozzini (1773–1809) and the lichtleiter. Urology. 1974;3:113–118.
2. Saxena AK. History of endoscopic sinus surgery. In: Saxena AK, Hollworth ME, eds. Essentials of Pediatric Endoscopic Surgery. Springer,
Berlin; 2009:3–16.
3. Doglietto F, Prevedello DM, Jane JA Jr, Han
J, Laws ER Jr. A brief history of endoscopic
transsphenoidal surgery — from Philipp
Bozzini to the First World Congress of Endoscopic Skull Base Surgery. Neurosurg Focus.

2005;19(6):1–6.


4  Office-Based Rhinology:  Principles and Techniques
4. Reuter M. The historical development of endophotography. World J Urol. 2000;18:299–
302.
5. Mouton WG, Bessell JR, Madderns GJ. Looking back to the advent of modern endoscopy:
150th birthday of Maximilian Nitze. World J
Surg. 1998;22:1256–1258.
6. Nezhat C. The glory days of endoscopy. In:
Nezhat’s History of Endoscopy. 2005: http://
laparoscopy.blogs.com/endoscopyhistory/
7. Mouret P. How I developed laparoscopic cholecystectomy. Ann Acad Med Singapore. 1996;​
25:744–747.
8. Satava RM. Surgical robotics: the early chronicles. Surg Laparosc, Endosc Percutan Tech.
2003;12:6–16.

9.Draf W. Endoscopy of the Paranasal Sinuses.
Berlin: Springer-Verlag; 1983:4–9.
10. Messerklinger W. Background and evolution
of endoscopic sinus surgery. ENT Journal.
1994;73(7):449–450.
11. Kennedy DW. Functional endoscopic sinus
surgery: technique. Arch Otolaryngol. 1985;​
111:​643–649.
12. Pownell PH, Minoli JJ, Rohrich RJ. Diagnostic nasal endoscopy. Plast Reconstr Surg. 1997;​
99:​1451–1458.
13. Messerklinger W. Endoscopy of the Nose. Baltimore, MD: Urban & Schwarzenberg; 1978.
14. Schaefer SD. An anatomic approach to endoscopic intranasal ethmoidectomy. Laryngoscope. 1998;108:1628–1634.

Chapter

2
Endoscopic Anatomy for Office-Based
Rhinology Procedures
Sarah K. Wise
Craig Villari
John M. DelGaudio

Introduction
Endoscopic paranasal sinus surgeons must
have a solid understanding of the complex
anatomic relationships of the nose and paranasal sinuses in order to appropriately care
for patients with disease in this area. This
knowledge of paranasal sinus anatomy and
pathophysiology is often translated to planning procedural approaches to the nose and
paranasal sinuses in the office and operating
room. This chapter reviews the anatomy of the
nose and paranasal sinuses, with special attention to endoscopic anatomy for office-based
rhinology procedures.

Structural Framework of
the Paranasal Sinuses and
Nasal Cavity
The paranasal sinus and nasal cavity structure
has contributions from eight major bones of
the face and skull. These include the maxilla,
and the ethmoid, sphenoid, and frontal bones,

which contribute to the overall shape and aerated structure of the paranasal sinus cavities.
The nasal bones, lacrimal bones, zygomatic
bones, and vomer are also important in completing the bony framework of the nasal and
paranasal sinus cavities. The remainder of the
nasal cavity structure anteriorly largely comes
from the upper lateral cartilage and lower
lateral cartilage of the external nose and the
quadrangular cartilage of the nasal septum.
The most anterior of the nasal cavity,
or vestibule, is the region in which the squamous epithelial surface of the facial skin transitions to the moist respiratory mucosa of the
nasal and paranasal sinus cavities. On initial
endoscopic inspection of the nasal cavity, the
most prominent structures will be the inferior
turbinate laterally, the nasal septum medially,
and the middle turbinate a bit more posteriorly (Figure 2–1). The turbinates are bony
structures that emanate from the sidewalls
of the nose (inferior turbinates) or skull base
(medial, superior, and supreme turbinates) and
are essentially covered by a mucosal surface on
all sides, except at their bony attachment sites.
The middle and superior turbinates are especially important landmarks for endoscopic


6  Office-Based Rhinology:  Principles and Techniques

Figure 2–1. Endoscopic view of the left
nasal cavity in a patient who has not had
prior sinus surgery. The nasal septum (NS),
left middle turbinate (MT), and left inferior
turbinate (IT) are labeled.

procedures in rhinology. The middle turbinate
assists in directing the surgeon to the middle
meatus, maxillary sinus ostium, anterior ethmoid cavity, and frontal recess. The superior
turbinate is quite helpful in identifying the
natural ostium of the sphenoid sinus. The
nasal septum divides the right and left sides
of the nasal cavity and is composed of the
quadrangular cartilage at its anterior aspect,
maxillary crest and vomer inferiorly, and perpendicular plate of the ethmoid bone superiorly as it attaches to the skull base. Finally, the
right and left choanae denote the most posterior aspect of the nasal cavities, beyond which
the nasopharynx and eustachian tube orifices
can be visualized.

Middle Meatus and
Associated Structures
Middle Turbinate
As stated previously the middle turbinate
serves as an important landmark for endo-

scopic sinus dissections within the anterior
ethmoid cavity and frontal recess. Most surgeons performing endoscopic paranasal sinus
procedures are familiar with seeing the anterior free edge of the middle turbinate bordering the entrance to the middle meatus.
This middle turbinate free edge exists in the
parasaggital plane. The intricate structure of
the middle turbinate also has components
that occur in the semicoronal and semiaxial
planes, as the turbinate attaches to the skull
base, lamina papyracea, and lateral nasal wall.
These semicoronal and semiaxial components

of the middle turbinate comprise the vertical
and horizontal aspects of the middle turbinate
basal lamella, respectively. The middle turbinate basal lamella divides the anterior and posterior ethmoid cavities (Figure 2–2).
Pneumatization of the middle turbinate
occurs with some frequency.1–3 Most commonly, we recognize pneumatization of the
free, parasaggital portion of the middle turbinate, which is denoted as a middle turbinate
concha bullosa (Figure 2–3). However, pneumatization of the vertical portion of the middle turbinate may also occur; this is termed an
intralamellar cell.

Uncinate Process
The uncinate process extends from the lateral
nasal wall and forms a hook-shaped structure with vertical and horizontal portions.
The vertical portion of the uncinate process
attaches to the maxilla near the lacrimal bone,
and its free edge extends posteriorly from this
region.4 The superior attachment of the vertical portion of the uncinate process is variable
and thus affects the drainage pattern of the
frontal sinus.3,4 The most common configuration seen is that the superior aspect of the
uncinate process attaches to the lamina papyracea, with the frontal sinus draining medial
to this attachment, into the middle meatus.


Endoscopic Anatomy for Office-Based Rhinology Procedures  7

Figure 2–2. Endoscopic view of the left
paranasal sinus cavities in a patient who
has undergone left maxillary antrostomy
and anterior ethmoidectomy. The middle
turbinate is medialized, and the leading
edge of the parasaggital portion of the

middle turbinate is labeled MT. The vertical
and horizontal portions of the middle
turbinate basal lamella are labeled V and
H, respectively. This picture shows all
three portions of the left middle turbinate,
which is often difficult to conceptualize. The
posterior ethmoid cavity lies posterior to
the middle turbinate basal lamella. (LNW =
lateral nasal wall)

Figure 2–3.  Coronal CT scan in bone
window algorithm demonstrating a large
right middle turbinate concha bullosa.

cess and laterally by the structures of the lateral
nasal wall and anterior ethmoid air cells. The
ethmoid infundibulum has as its borders the
lamina papyracea laterally, the uncinate process
anteriorly and medially, and the ethmoid bulla
posteriorly. The natural ostium of the maxillary sinus drains into the ethmoid infundibulum, as does the frontal sinus at times.

Agger Nasi Cells
The superior aspect of the uncinate process
may alternatively attach to the skull base or to
the middle turbinate, in which case the frontal
sinus would drain to the ethmoid infundibulum, lateral to the uncinate process.

Hiatus Semilunaris and
Ethmoid Infundibulum
The hiatus semilunaris is the two-dimensional

“doorway” that forms the entrance to the threedimensional “space” of the ethmoid infundibulum. The hiatus semilunaris is bordered medially
by the posterior free edge of the uncinate pro-

The most anterior of all ethmoid cells is the
agger nasi cell. Agger nasi cells and the agger
nasi region are most commonly discussed due
do their importance in endoscopic frontal
sinus dissections and appropriate drainage of
the frontal sinus outflow tract. The agger nasi
cell is located near the confluence of the lacrimal bones, nasal bones, and maxilla. In considering frontal recess dissections, the agger
nasi region is anterior and lateral to the frontal
sinus drainage pathway. Incomplete removal
of agger nasi walls or septations may lead to
obstruction of appropriate frontal sinus drainage5 (Figure 2–4).


8  Office-Based Rhinology:  Principles and Techniques

Ethmoid Complex

A

B
Figure 2–4.  Coronal (A) and sagittal (B)
CT scans in bone window algorithm
demonstrating agger nasi cells (arrows).
On sagittal scan in particular, the potential
for the posterior aspect of the agger nasi
cell to narrow the frontal sinus drainage
pathway can be appreciated.

Ethmoid Bulla
The ethmoid bulla is typically the largest of
the anterior ethmoid cells. Upon dissection
of the anterior ethmoid cavity, the ethmoid
bulla is noted as a prominent protuberance
lying posterior to the vertical portion of the
uncinate process. The lateral attachment of
the ethmoid bulla is the lamina papyracea. It
is further bordered anteriorly by the ethmoid
infundibulum and posteriorly by the vertical
portion of the middle turbinate basal lamella
and the retrobullar recess.

Initiating its development by budding from
the middle meatus around 11 to 12 weeks
of fetal life, the ethmoid complex is the first
of the paranasal sinuses to develop embryologically.6,7 The ethmoid complex and lamina
papyracea are ossified by 20 to 24 weeks of
embryologic development.6,7 At birth, the ethmoid cells have reached their adult number,
but they are not fully developed in size. This
makes the ethmoid complex the most mature
of the paranasal sinuses at birth.8
Unlike the maxillary, frontal, and sphenoid sinuses, each of which consists of a large
cavity draining to a single ostium, the ethmoid
sinus is a complex of small ethmoid sinus cells.
The anterior and posterior ethmoid cavities
are separated by the basal lamella of the middle turbinate (see Figure 2–2). The anterior
ethmoid complex is bounded medially by the
parasaggital portion of the middle turbinate

and drains to the middle meatus. The posterior ethmoid complex is bounded medially by
the parasagittal portion of the superior turbinate and drains to the superior meatus.
Two notable anterior ethmoid sinus cells
have already been discussed: the ethmoid bulla
and the agger nasi cell. Another ethmoid sinus
cell of significant importance is the infraorbital
ethmoid cell, previously known as the Haller
cell, which pneumatizes along the medial
inferior orbit and may narrow the maxillary
sinus drainage pathway into the infundibulum. Named cells emanating from the anterior ethmoid complex may also play a role in
anatomic narrowing of the frontal recess. For
example, the supraorbital ethmoid cell pneumatizes from the ethmoid cavity superiorly and
laterally over the bony orbit and has an ostium
that drains posteriorly and laterally to the true
frontal sinus ostium (Figure 2–5).
As stated previously, the vertical portion
of the basal lamella forms the anterior boundary of the posterior ethmoid complex, and the


Endoscopic Anatomy for Office-Based Rhinology Procedures  9

proximity of the optic nerve as it transitions
from the optic chiasm and progresses toward
the orbital apex. In fact, with good pneumatization, the bony impression of the optic
nerve and carotid artery may often be seen as
impressions on the walls of sphenoethmoid
cells. Sphenoethmoid cells may occur in as
many as 30% of patients and are important
to recognize to ensure appropriately thorough
and safe endoscopic dissections.9

A

B
Figure 2–5.  Coronal (A) and axial (B) CT
scans in bone window algorithm showing
supraorbital ethmoid cells (arrows), which
drain posteriorly and laterally to the true
frontal sinus ostium.

superior turbinate forms the medial boundary
of the posterior ethmoid complex. Superiorly,
the posterior ethmoid region is bounded by
the skull base, and laterally by the lamina
papyracea. In number, the posterior ethmoid
complex typically has fewer cells than the
anterior ethmoid complex.
One named posterior ethmoid cell is of
particular importance: the sphenoethmoid cell,
or Onodi cell. At times confused for a septated sphenoid sinus, a sphenoethmoid cell
is posterior ethmoid cell that is pneumatized
superiorly and laterally to the true sphenoid
sinus. The sphenoethmoid cell comes into

Maxillary Sinus
The infundibulum that will eventually lead to
the maxillary sinus cavity begins to develop
around 14 to 16 weeks of fetal development,
as an invagination into the maxillary bone.6 At
17 to 18 weeks gestation, the cavity that will
become the maxillary sinus air space can be

seen.10 By birth, the maxillary sinus is 10 mm
in its maximum dimension, and it continues
to aerate until it reaches its adult dimensions
around age 12.8
Often, one of the initial steps in endoscopic sinus surgery is identification of the
natural ostium of the maxillary sinus as it
drains into the ethmoid infundibulum. Opening this natural maxillary sinus ostium allows
the endoscopic surgeon to view the maxillary
sinus cavity, which is volumetrically the largest of the paranasal sinuses (Figure 2–6). The
maxillary sinus has as its borders the alveolar
portion of the maxillary bone anteriorly, the
zygoma laterally, the pterygopalatine fossa
and infratemporal fossa posteriorly, the lateral nasal wall medially, and the orbital floor
superiorly.1
It is important to note that the natural
ostium of the maxillary sinus will be located
within the ethmoid infundibulum, covered by
the uncinate process in an unoperated patient,
and out of view during routine nasal endoscopy. Accessory ostia may be visible at the
anterior or posterior fontanelles in as many


10  Office-Based Rhinology:  Principles and Techniques

on the ipsilateral side, and extreme care must
be taken in dissecting around the natural maxillary sinus ostium to avoid orbital injury. This
is especially true in the setting of office-based
rhinology procedures, which do not offer the
option of general anesthesia or muscle relaxation to ensure that the patient is completely
still during dissection of the paranasal sinuses.

Frontal Sinus
Figure 2–6. Endoscopic view of left para­
nasal sinus cavities following endoscopic
sinus surgery. The left maxillary sinus ostium
is widely patent, and the large volume of
the maxillary sinus can be appreciated.

as 23% of patients.11 These anterior and posterior fontanelles are found along the lateral
nasal wall (medial wall of the maxillary sinus)
in areas where the bone, connective tissue, and
mucosa are deficient, resulting in accessory
maxillary sinus ostia.
Infraorbital ethmoid cells, or Haller cells,
have already been discussed. These are generally anterior ethmoid cells that are found along
the medial inferior orbit and may narrow the
maxillary sinus drainage pathway. Most commonly, infraorbital ethmoid cells originate
from the anterior ethmoid cavity, but they
may originate from the posterior ethmoid cavity in as many as 12% of cases.2,12
Alterations in the expected adult volume
of the maxillary sinus may occur in certain
cases. Such instances include cases of maxillary silent sinus syndrome or negative pressure
phenomena and cystic fibrosis, among others.
Likewise, younger children have underdeveloped paranasal sinus cavities with substantially less aeration than a fully developed adult.
In these cases, the maxillary sinus volume is
smaller with respect to the orbital volume

As the last of the paranasal sinuses to develop,
the frontal sinus is typically not aerated at
birth. Around the age of 4 years, the frontal

sinus is 11 to 19 mm in width.8 The frontal
sinus reaches its tetrahedral shape around age
12, and continues aeration into early adulthood.8 The borders of the frontal sinus include
the anterior and posterior tables of the frontal bone. The bony interfrontal sinus septum
is located medially. Laterally, the floor of the
frontal sinus is composed of the orbital roof.
The frontal sinus outflow tract and frontal
recess are known amongst rhinologic surgeons
as challenging regions for surgical dissection
and areas where stenosis and recurrence of
disease often occurs. The frontal recess forms
an hourglass shape where the contents of the
frontal sinus contents drain into the ethmoid
infundibulum or middle meatus.2 The frontal
recess has as its boundaries: the frontal sinus
superiorly, the nasal cavity inferiorly, the agger
nasi region anteriorly, the ethmoid bulla posteriorly, the middle turbinate medially, and
the lamina papyracea laterally (Figure 2–7).
The anatomy of the frontal recess is
highly variable from patient to patient, with
a number of named cells and other unnamed
anatomic variants often playing a role. The
focus of this text on office-based rhinologic
procedures does not lend itself to an extensive description of frontal recess anatomy for
endoscopic dissection. However, some of the


Endoscopic Anatomy for Office-Based Rhinology Procedures  11

Figure 2–7. Endoscopic view of the left

frontal sinus ostium (white arrow) following
endoscopic sinus surgery. The anterior
ethmoid artery can be seen traveling
just posterior to the frontal recess, in a
posterior-lateral to anterior-medial direction
(black arrow).

more common anatomic variants will be mentioned for the sake of completeness.
Two main types of frontal recess cells are
located in an anterior-lateral position with
respect to the true frontal sinus ostium: agger
nasi cells and frontal cells. Agger nasi cells have
already been discussed. Agger nasi are the most
anterior of all ethmoid cells, pneumatizing just
superior to the lacrimal region and encroaching on the frontal sinus drainage pathway
from an anterior and lateral direction (see
Figure 2–4). Second, types 1 through 4 frontal
cells which pneumatize superior to the agger
nasi cells. Dependent on their classification,
frontal cells may or may not pneumatize into
the frontal sinus itself.13,14 The type 1 frontal
cell is a solitary anterior ethmoid cell located
superior to the agger nasi cell, which does
not aerate into the frontal sinus. The type 2
frontal cell is defined as multiple “stacked”
cells located superior to the agger nasi cell,
which may or may not aerate into the frontal
sinus. The type 3 frontal cell is a solitary large

cell, located superior to the agger nasi cell,

which aerates into the frontal sinus and communicates with the frontal recess. The type 4
frontal cell is a cell located entirely within the
frontal sinus, attached to the anterior table of
the frontal sinus.14
Certain ethmoid cells and recesses may
pneumatize into the frontal recess and are
located in a posterior position with respect
to the frontal sinus drainage pathway. The
supraorbital ethmoid cell has previously been
mentioned. This is an ethmoid cell pneumatizing superiorly and laterally over the orbit
and draining posteriorly and laterally in comparison to the drainage of the frontal sinus.
The suprabullar recess is located superior to the
ethmoid bulla when the ethmoid bulla does
not come into contact with the skull base. The
term suprabullar recess denotes an open space,
whereas the term suprabullar cell is used when
the space is closed and forms a true cell. Next,
the term frontal bulla cell is used when an
ethmoid cell pneumatizes along the posterior
table of the frontal sinus and into the frontal
recess. Like the suprabullar cell, the ostium of
the frontal bulla cell drains posterior to the
ostium of the true frontal sinus.
Finally, a frontal intersinus septal cell exists
when the frontal intersinus septum becomes
pneumatized. The frontal intersinus septal cell
drains into either the right or left frontal sinus.
The ostium of the frontal intersinus septal cell
will be located medially with respect to the
true frontal sinus ostium.

Sphenoid Sinus
Although the sphenoid sinus begins to develop
around the third to fourth month of fetal life,
at birth typically only the sphenoid sinus
ostium is evident.15,16 The sphenoid sinus
begins to pneumatize around age 1.15 And,
although there is some debate about the age at


12  Office-Based Rhinology:  Principles and Techniques

which the sphenoid sinus completes its aeration, certain authors note that the adult size
of the sphenoid sinus is achieved by approximately age 12.8,15
The boundaries of the sphenoid sinus
include the planum sphenoidale (a portion
of the posterior skull base) superiorly, and the
sphenoid floor and rostrum inferiorly. The
thin anterior wall of the sphenoid sinus is at
the posterior extent of the nasal cavity. The
posterior boundaries of the sphenoid sinus
include the sella turcica and clivus. The sphenoid intersinus septum divides the right and
left sphenoid sinuses. The sphenoid intersinus
septum is commonly oriented off-midline,
resulting in unequal volumes between the
right and left sphenoid sinus cavities.
Various landmarks are often used to identify the natural ostium of the sphenoid sinus.
Traditional teaching notes that the sphenoid
sinus ostium sits approximately 7 cm posterior
to the nasal spine, at a 30-degree angle superiorly. Endoscopically, the natural sphenoid

sinus ostium can be found 1 to 1.5 cm above
the superior aspect of the choana, between the
nasal septum and the superior turbinate.17
The sphenoid sinus is surrounded by
many vital structures, including the pituitary
gland superiorly and medially, the optic chiasm superior to the pituitary gland, the optic
nerves superiorly and laterally, and the carotid
arteries posteriorly and laterally. The cavernous sinus houses cranial nerves III, IV, V1, V2,
and VI and is located laterally with respect to
the pituitary gland. Due to these extremely
important structures, great care must be taken
in any manipulation of the sphenoid sinus in
any setting.

Skull Base
The skull base slopes from a more superior
position in the anterior lateral paranasal sinuses

to an inferior position in the medial and posterior aspects. The skull base also thins medially
around the attachment of the medial turbinate
to the skull base and cribriform plate, and has
been shown to be only 0.2 mm thick in certain locations.18 Use of the Keros classification
system to quantify the height of the olfactory
sulcus and determine potential risk for cerebrospinal fluid leak may help in planning for
endoscopic paranasal sinus procedures. Keros
type 1 signifies an olfactory sulcus depth from
1 to 3 mm, Keros type 2 denotes a depth of 4
to 7 mm, and Keros type 3 classifies those with
a depth from 8 to 16 mm. With increasing
Keros depth, the theoretical risk of iatrogenic

cerebrospinal fluid leak in the ethmoid region
increases. Solares and colleagues have noted
that the most common Keros depth is Keros
type 1, at approximately 83%.19
The ethmoid arteries, which emanate
from the carotid artery system, also run along
the ethmoid skull base. The anterior ethmoid
artery exits from the orbit, running in an anterior medial direction, and inserts medially
along the ethmoid roof at the lateral lamella
of the middle turbinate (see Figure 2–7). The
anterior ethmoid artery may be seen in a mesentery below the bony skull base at times, a
configuration that should be noted on imaging in order to prevent injury in this area.

Conclusions
The nasal and paranasal sinus anatomy is
complex and may be daunting to beginning
surgeons. However, with careful study of this
anatomy, the surgeon will gain comfort in
performing procedures in this region. Study
of the nasal and paranasal sinus anatomy is
essential to planning for procedures both in
the operating room and in the office, in order
to perform complete procedures and avoid
unnecessary complications.