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54
P. Nicolai et al.
a
Fig. 5.15 a,b. Partial medial maxillectomy with ethmoidectomy
and/or the medial wall of the maxillary sinus. In many
benign lesions, the operation can also be performed
transnasally with a microendoscopic approach, but for
most malignant lesions an external approach is still
the option of choice. Medial maxillectomy has been
traditionally performed through a lateral rhinotomy
approach (Fig. 5.16), but in recent years a common
tendency to resort to midfacial degloving (Casson et
al. 1974) has been observed. This surgical technique is
characterized by the association of sublabial and rhinoplastic incisions, with or without osteotomies at the
level of nasal bones and the frontal process of the maxilla (Fig. 5.17).
Fig. 5.16. Lateral rhinotomy incision
b
The fi rst step is a bilateral intercartilaginous incision at the level of the nasal vestibulum; the procedure
then proceeds with nasal soft tissue dissection from
lateral cartilages and nasal septum by means of an incision that divides it from the columella. The intercartilaginous incisions go on bilaterally until the fl oor of
the vestibulum, joining together with the septal incision. The second step is another incision at the level
of mucosa of the superior buccal vestibulum extended
to the third molar bilaterally, followed by a subperiosteal dissection which exposes the anterior wall of both
maxilla, the inferolateral margins of the pyriform fossa,
and the infraorbital nerves up to the inferior frame of
the orbits. At this point, the nasal-maxillary cavity is
entered by entirely resecting the anterior wall of the
maxillary sinus. In the case of benign lesions or of malignant lesions not involving the anterior wall, it can be
temporarily removed and fi xed back at the end of the
operation with microplates in titanium or in reabsorbable material.
Midfacial degloving, which currently represents
the gold standard for the surgical treatment also of
neoplasms of the nasopharynx (i.e., juvenile angiofi broma) not amenable to microendoscopic surgery, has
the advantage of avoiding evident scars and of maintaining good vascularization of the facial fl ap. Major
limitations are, however, an anterior extension of the
neoplasm with involvement of the nasal bones, lacrimal
pathways, and/or pre-maxillary soft tissues, a superior
growth into the frontal sinus, and all the situations in
which the inferior and/or the medial walls of the orbit
are eroded by the lesion and a careful dissection from
the periorbit is therefore required. In all these situations a lateral rhinotomy approach, with or without
Endonasal and Open Surgery: Key Concepts 55
Fig. 5.17. Midfacial degloving
superior lip splitting (Fig. 5.16), which gives an excellent exposure of the surgical fi eld and ensures a good
control of the dissection along the inferior and medial
orbital walls, is still indicated.
The same access is recommended for radical maxillectomy (Fig. 5.18) and extended radical maxillectomies, which may require the association of an infratemporal approach or a frontal craniotomy whenever
the lesion extends far posteriorly or superiorly to invade the skull base, respectively.
The goal of modern oncologic surgery of the sinonasal tract is not only to provide a radical extirpation
of the lesion, but also to preserve to the best possible
extent functions such chewing, eating, and speaking, as
well as aesthetic appearance. Different techniques can
be employed principally in relation to the entity of the
ablative procedure.
A prosthetic obturator is a simple s olution for a small
defect after inferior maxillectomy. A clasp-retained
obturator can later be substituted by a more stable one
based on bone-anchored implants. Problems of prosthetic stability derive from excision of more than half
the palate. In such cases, a tripod-like stabilization of
the obturator can be obtained by means of bone graft
or, even better, with one of the more reliable revascularized free osseous fl aps (from scapula, iliac crest, fi bula, or radium) (Funk et al. 1998). In toothless patients,
soft tissue fl aps can be suffi cient to separate the sinonasal tract from the oral cavity. For less than half-palate
defects, a pedicled temporalis muscle fl ap can still be
considered an option, particularly when in combination with total or extended maxillectomy; it is easy to
harvest and the risk of failure is very low (Colmenero
et al. 1991). On the other hand, larger palatal excision
b
a
Fig. 5.18 a,b. Radical maxillectomy
56
P. Nicolai et al.
without need of dental rehabilitation should be closed
by a radial free fl ap or with the muscular portion of
other composite fl aps (scapular, fi bular, or iliac crest).
Iliac crest, scapula, and fi bula, if appropriately harvested and oriented, can be even used to adequately
restore the anterior maxillary contour and three-dimensional projection of the face when the anterior
wall of the maxillary and zygomatic bones have been
removed.
When more than half of the orbital fl oor needs to
be resected, reconstruction with split calvarial bone
is mandatory to prevent sequelae such as diplopia or
enophthalmos. Moreover, the membranous portion of
cranial bones like the parietal one, seems to be reabsorbed less frequently than the endochondral bones
previously used (rib and iliac crest), even during radiotherapy (Zins and Whitaker 1993). However, me-
ticulous coverage of the graft by soft tissues should be
always obtained.
In the case of extended maxillectomies, a number
of different situations can be encountered depending
on the specifi c structures removed. Large cheek or
scalp defects can be closed by free fl aps (radial, rectus abdominis or parascapular) with the appropriate
bulk. External nose and auricular defects are usually
restored by prostheses; pedicled or free fl aps simply
play the role of cover for the surgical wound to prepare tissues for prosthesis retention. Orbital exenteration usually poses more challenging problems. A pure
soft lining of the orbital cavity can be achieved by the
temporalis muscle, over which a prosthesis will be later
positioned (Turner et al. 1999). The orbit can be alternatively fi lled by soft tissue transfer if an adjacent
skull base defect demands it or when ocular prosthesis
is not desired.
the pericranium to leave the pericranium adherent to
the underlying bone, so as to maintain an adequate
vascularization to the bone. With the help of a template of the frontal sinus, obtained from a Caldwell
view the superior margin of the sinus is identifi ed and
a cut is made in the bone along this margin with an
oscillating saw (Fig. 5.20). Using a chisel, the bony fl ap
is gently down-fractured attached to the pericranium
Fig. 5.19. Different incisions for osteoplastic frontal sinusotomy: coronal incision (broken red line) and “butterfl y” or
“seagull” incision (solid red line)
5.3.2
Osteoplastic Flap Sinusotomy
This operation is currently considered the gold standard whenever an external approach to the frontal
sinus is required after failure of previous endonasal
procedures or when the disease cannot be adequately
reached transnasally. The anterior wall of the frontal sinus may be exposed through a coronal incision,
which is carried out far posteriorly to be hidden by the
hair line, or a “butterfl y” or “seagull” incision, which is
performed along the superior border of the eyebrows
(Fig. 5.19). Our preference is for coronal incision, since
the latter may leave the patient with a visible scar and
some numbness of the forehead. Soft tissue dissection
is then carried along the plane between the galea and
Fig. 5.20. A skin-galeal frontal fl ap has been dissected and
downward refl ected. With the help of a template, a bony fl ap
is created and down-fractured
Endonasal and Open Surgery: Key Concepts 57
and the frontal sinus is entirely exposed. The original
technique includes careful removal of the disease (i.e.,
mucocele, osteoma) together with all the mucosa lining the sinus, plugging of both frontal infundibula with
cartilage and/or muscle, and obliteration of the sinus
with fat obtained through a small incision made in the
abdominal wall. In our experience, in selected patients
who have an extremely localized disease not involving
the infundibulum area in an otherwise well ventilated
sinus, obliteration of the sinus may be avoided.
A coronal approach is routinely indicated for osteomyelitis of the frontal bone, which usually complicates
an acute frontal rhinosinusitis. The entit y of bony resection must be tailored to the extent of the osteomyelitic
process. If the anterior wall is involved, obliteration of
the sinus with fat is obtained and reconstruction of the
bony wall is secondarily performed, when there will be
clear clinical and radiological signs that the infl ammatory process has been controlled. When osteomyelitis
affects the posterior wall of the frontal sinus, this needs
to be resected; cranialization of the sinus is performed
after sealing both frontal infundibula with cartilage or
muscle to prevent any contamination from the nasal
cavities.
Whenever the lesion is in close contact with the skull
base, but there are no radiologic and intraoperative
signs of bony involvement, the procedure can be carried out extradurally and the dissection superiorly
includes the cribriform plate and the fovea ethmoidalis. Those lesions eroding the skull base and possibly
infi ltrating the dura dictate instead a wide resection
of the dura. The ablative part of the operation must
be further extended to include a variable amount of
brain parenchyma when the lesion is clearly in contact or even infi ltrates the frontal lobe(s). Dura defects
require multiple-layer duraplasty which can be performed with different autologous and/or homologous
materials. An anteriorly-pedicled pericranium fl ap
down-folded and fi xed posteriorly to the planum sphenoidale is commonly used to reinforce the duraplasty
and to offer a nicely vascularized barrier, which divides
the sinonasal tract from the cranium.
5.3.3
Anterior Craniofacial Resection
Even though anecdotal examples of operative techniques anticipating the concept of anterior craniofacial
resection were published in the 1940s (Dandy 1941)
and 1950s (Malecki 1959), Ketcham et al. (1963)
must be credited with the fi rst results on a group of
19 patients with malignant tumors, most originating
from the sinonasal tract, who had received anterior
craniofacial resection. This surgical technique can be
considered the major innovative procedure among the
external approaches of the last four decades, since it
has markedly contributed to improving the prognosis
of malignant tumors encroaching the anterior skull
base. The basic concept of the operation is to obtain
additional exposure of the tumor from above and to
ensure even superiorly a free margin of resection. This
is usually achieved through a coronal incision and a
frontal craniotomy, which, accoording to Raveh et
al. (1993), is harvested as low as possible to obtain a
good view on the anterior skull base without undue
retraction of the frontal lobes (Fig. 5.21). A midfacial
degloving, a lateral rhinotomy approach, or even in
selected cases a transnasal microendoscopic approach
(Thaler et al. 1999) is associated to perform the dissection of the inferior part of the surgical specimen.
a
b
Fig. 5.21. a Access to the anterior cranial fossa through a coro-
nal incision (red line, frontal craniotomy). b Posteriorly the
resection reaches the planum sphenoidale
58
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Bolger WE, Keyes AS, Lanza DC (1999) Use of the superior meatus
and superior turbinate in the endoscopic approach to the
sphenoid sinus. Otolaryngol Head Neck Surg 120:308-313
Casson PR, Bonanno PC, Converse JM (1974) The midfacial
degloving procedure. Plast Reconstr Surg 53:102-113
Colmenero C, Martorell V, Colmenero B et al (1991) Tempora-
lis myofascial fl ap for maxillofacial reconstruction. J Oral
Maxillofac Surg 49:1067-1073
Dandy WE (1941) Orbital tumors. Oskar Priest Publications,
New York
Draf W (1991) Endonasal micro-endoscopic frontal sinus sur-
gery, the Fulda concept. Op Tech Otolaryngol Head Neck
Surg 2:234-240
Draf W, Weber R, Keerl R et al (2000) Endonasal and external
micro-endoscopic surgery of the frontal sinus. In: Stamm
A, Draf W (eds) Microendoscopic surgery of the paranasal
sinuses and the skull base. Springer-Verlag, Berlin Heidelberg New York, pp 257–278
Draf W, Weber R (1993) Endonasal pansinus operation in
chronic sinusitis. I: Indication and operation technique.
Am J Otolaryngol 14:394-398
Funk GF, Arcuri MR, Frodel JL (1998) Functional dental reha-
bilitation of massive palatomaxillary defects: cases requiring free tissue transfer and osseointegrated implants. Head
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Goffart Y, Jorissen M, Daele J et al (2000) Minimally invasive
endoscopic management of malignant sinonasal tumors.
Acta Otorhinolaryngol Belg 54:221-232
Gross CW, Gross WE, Becker DG (1995) Modifi ed transnasal
endoscopic Lothrop procedure: frontal drillout. Op Tech
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Heermann H (1958) Endonasal surgery with the use of the
binocular Zeiss operating microscope. Arch Klin Exp
Ohren Nasen Kehlkopfheilkd 171:295-297
Ketcham AS, Wilkins RH, van Buren JM et al (1963) A com-
bined intracranial facial approach to the paranasal sinuses.
Am J Surg 106:698-703
Malecki J (1959) New trends in frontal sinus surgery. Acta Oto-
laryngol (Stockh) 50:137-140
Messerklinger W (1972) Technik und Möglichkeiten der
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Messerklinger W (1978) Endoscopy of the nose. Urban and
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Nicolai P, Berlucchi M, Tomenzoli D et al (2003) Endoscopic
surgery for juvenile angiofi broma: when and how. Laryngoscope 113:775-782
Orlandi RR, Lanza DC, Bolger WE et al (1999) The forgotten
turbinate: the role of the superior turbinate in endoscopic
sinus surgery. Am J Rhinol 13:251-259
Raveh J, Leadrach K, Speiter M et al (1993). The subcranial
approach for fronto-orbital and anteroposterior skull-base
tumors. Arch Otolaryngol Head Neck Surg 119: 385-393
Roger G, Tran Ba Huy P, Froehlich P et al (2002) Exclusively
endoscopic removal of juvenile nasopharyngeal angiofi broma: trends and limits. Arch Otolaryngol Head Neck
Surg 128:928-935
Roh HJ, Batza PS, Citazdi, MJ et al (2004) Endoscopic resec-
tion of sinonasal malignancies: a preliminary report. Am
J Rhinol 18:239-248
Schick B, Steigerwald C, el Tahan R et al (2001) The role of
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Stamm AC, Draf W (2000) Micro-endoscopic surgery of the
paranasal sinuses and the skull base. Springer, Berlin Heidelberg New York
Stammberger H (1986a) Endoscopic endonasal surgery-con-
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Stammberger H (1986b) Endoscopic endonasal surgery-con-
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Stammberger H, Anderhuber W, Walch C et al (1999) Possi-
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and paranasal sinus malignancies. Acta Otorhinolaryngol
Belg 53:199-205
Thaler ER, Kotapka M, Lanza DC et al (1999) Endoscopically
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tumors. Am J Rhinol 13:303-310
Tomenzoli D, Castelnuovo P, Pagella F et al (2004) Differ-
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47 cases. Laryngoscope 114:193–200
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Infl ammatory Lesions 59
6 Infl ammatory Lesions
CONTENTS
6.2 Acute Rhinosinusitis and Its Complications 59
6.2.1 Defi nition, Epidemiology, Pathophysiology,
and Etiology 59
6.2.2 Clinical and Endoscopic Findings 60
6.2.3 Treatment Guidelines 61
6.2.4 Key Information to Be Provided by Imaging 62
6.2.5 Imaging Findings 62
6.3 Chronic Rhinosinusitis and Polyposis 65
6.3.1 Defi nition, Epidemiology, Pattern of Growth 65
6.3.2 Clinical and Endoscopic Findings 66
6.3.3 Treatment Guidelines 67
6.3.4 Key Information to Be Provided by Imaging 68
6.3.5 Imaging Findings 68
6.3.5.1 Infundibular Pattern 68
6.3.5.2 Ostiomeatal Unit Pattern 68
6.3.5.3 Sphenoethmoid Recess Pattern 69
6.3.5.4 Pattern of Nasal Polyposis 69
6.3.5.5 Sporadic Pattern 71
6.3.5.6 Chronic Rhinosinusitis: Staging Systems 72
6.4 Fungal Rhinosinusitis 72
6.4.1 Defi nition, Epidemiology, and Pathophysiology 72
6.4.2 Clinical and Endoscopic Findings 73
6.4.3 Treatment Guidelines 74
6.4.4 Key Information to Be Provided by Imaging 75
6.4.5 Imaging Findings 75
6.5 Aggressive Granulomatous Lesions 77
6.5.1 Wegener Granulomatosis 77
6.5.1.1 Defi nition and Epidemiology 77
6.5.1.2 Clinical and Endoscopic Findings 78
6.5.1.3 Treatment Guidelines 79
6.5.1.4 Key Information to Be Provided by Imaging 80
6.5.2 Cocaine Induced Destructive Lesions 80
6.5.2.1 Defi nition and Epidemiology 80
6.5.2.2 Clinical and Endoscopic Findings 80
6.5.2.3 Treatment Guidelines 81
6.5.2.4 Key Information to Be Provided by Imaging 81
D. Fari na, MD
Department of Radiology, University of Brescia, Piazzale
Spedali Civili 1, Brescia, BS, 25123, Italy
D. Tomenzoli, M D
Department of Otorhinolaryngology, University of Brescia,
Piazzale Spedali Civili 1, Brescia, BS, 25123, Italy
A. Borghesi, MD
Department of Radiology, University of Brescia, Piazzale
Spedali Civili 1, Brescia, BS, 25123, Italy
D. Lombardi, MD
Department of Otorhinolaryngology, University of Brescia,
Piazzale Spedali Civili 1, Brescia, BS, 25123, Italy
Davide Farina, Davide Tomenzoli, Andrea Borghesi, and Davide Lombardi
6.5.3 Sarcoidosis 81
6.5.3.1 Defi nition and Epidemiology 81
6.5.3.2 Clinical and Endoscopic Findings 82
6.5.3.3 Treatment Guidelines 82
6.5.3.4 Key Information to Be Provided by Imaging 83
6.5.4 Imaging Findings 83
References
88
6.2
Acute Rhinosinusitis and Its Complications
6.2.1
Defi nition, Epidemiology, Pathophysiology,
and Etiology
Rhinosinusitis is defi ned as an infl ammation of the
mucosa of the nose and paranasal sinuses. It is classifi ed as acute, subacute, and chronic according to
whether the duration of symptoms persists as long
as 4 weeks, between 4 and 12 weeks, and more than
12 weeks, respectively (Brook et al. 2000). More
than $2 billion is spent annually in the United States
for over-the-counter medications for rhinosinusitis
(National Center for Health Stati st ics 1994).
Even though data regarding the incidence of rhinosinusitis in the world population are scarce in the
literature, every year approximately 16% of adults in
the United States receive a diagnosis of rhinosinusitis
(National Center for Health Stati stics 1994).
If the forms of rhinosinusitis exclusively arising in
a single paranasal sinus, such as the maxillary sinus, in
relation to tooth disease, facial trauma, or paranasal sinus neoplasms are excluded, the fi rst step in the pathophysiology of most rhinosinusitis is almost invariably
an infl ammation with edema of the mucosa which involves one or both “pre-chambers” (ostiomeatal complex, sphenoethmoidal recess). This causes an obstruction of the dependent sinus outfl ow and creates an ideal
environment for pathogen and saprophytic bacteria.
In acute rhinosinusitis, the most frequently isolated
bacteria are Streptococcus pneumoniae, Haemophilus
infl uenzae, and Moraxella catharralis in 41%, 35%,
and 7% of cultures, respectively (Wald 1998).
60
D. Farina et al.
Apart from the duration of symptoms, acute and
subacute rhinosinusitis may be regarded as the same
disease, since they share the same etiology (infectious), pathogenesis (obstruction of the sinus drainage), medical therapy, and complications. For this
reason, they will be discussed together under the
term acute rhinosinusitis.
Despite the widespread use of broad-spectrum antibiotics, complications of acute rhinosinusitis may
still be a fatal event in a percentage ranging from
1% to 3.7% (Patt and Manning 1991; Younis et
al. 2002a). Bradley et al. (1984) and Younis et al.
(2002b) reported the occurrence of complications
in 0.5% and 11% of patients admitted to their institutions for rhinosinusitis, respectively. Intraorbital
and intracranial complications are more frequently
reported, while osteomyelitis and toxic shock syndrome are rarely encountered (Lusk 1992; Younis et
al. 2002a,b).
Orbital complications may be subdivided into fi ve
groups (Chandler et al. 1970):
Group 1. Preseptal cellulitis. Edema of the eyelids
without tenderness and with no associated visual
loss or limitation of extraocular motility
Group 2. Orbital cellulitis without abscess. Diffuse
edema of the adipose tissue in the orbit with no
abscess formation
Group 3. Orbital cellulitis with subperiosteal
abscess. Abscess formation between the orbital
periosteum and orbital bone; the abscess displaces
the globe, usually down and laterally; if the pro-
ptosis is severe, it will be associated with limita-
tion of ocular motility and perhaps decreased
visual acuity
Group 4. Orbital cellulitis with abscess within
the orbital fat. Proptosis may be purely frontally
directed and not laterally or inferiorly displaced
as in subperiosteal abscess; severe limitation of
extraocular motility results and visual loss due to
optic neuropathy may ensue
Group 5. Cavernous sinus thrombosis. Orbital
phlebitis extends into the cavernous sinus and
across the basilar venous plexus to the opposite
side, resulting in bilateral disease
In decreasing order of frequency, intracranial
complications are: subdural empyema, intracerebral
abscess, extradural abscess, meningitis, and, more
rarely, cavernous and superior sagittal sinus thrombosis (Jones et al. 2002).
According to some authors (Lang et al. 2001;
Noordzij et al. 2002; Younis et al. 2002a,b) complicated rhinosinusitis more frequently affects chil-
dren and adolescents, with a male/female ratio of 3:1
(Kraus and Tovi 1992).
Sinonasal infections reach the orbit and the intracranial cavity spreading through the neurovascular
foramina, congenital or acquired bony dehiscences,
or via a retrograde fl ow through the diploic valveless veins secondary to a thrombophlebitis. Since in
children the cranium has more diploic veins than in
adults, infections spread more deeply and more rapidly. This accounts for a higher incidence of severe
complications in children (Lusk 1992; Lang et al.
2001; Yo u n i s et al. 2002b).
6.2.2
Clinical and Endoscopic Findings
Patients with acute rhinosinusitis commonly complain of nasal obstruction, rhinorrhea, headache, facial pain, and dysosmia.
The occurrence of an orbital complication may be
suspected when fever, exacerbation of headache, and
ocular symptoms appear (Younis et al. 2002a). In the
presence of preseptal cellulitis, erythema and edema
of the eyelid without ophthalmoplegia or visual loss
are observed. When proptosis, chemosis, and impairment of extraocular movement occur, a subperiosteal
or intraorbital abscess must be suspected. When the
patient complains of a unilateral impairment or loss
of visual acuity, a compression of the optic nerve or
the ophthalmic artery or the small retinoic vessels
must be excluded. Acute headache, fever, and painful paresthesia in the distribution of the trigeminal
nerve are the early symptoms of cavernous sinus
thrombosis; they can be followed by afferent pupillary defect, extraocular motility palsy, and hyperesthesia of the cornea as a consequence of trigeminal
nerve infl ammation (Lusk 1992). An ominous sign
is the appearance of bilateral orbital involvement,
which indicates a propagation of the infection to the
opposite side through the cavernous sinus plexus
(Shahin et al. 1987).
Whenever an orbital complication is observed,
ophthalmologic consultation is mandatory to disclose
any possible sign (optic disc pallor, papilledema, decreased venous pulsation) suggesting an impairment
of blood fl ow.
In a patient with acute rhinosinusitis, the onset
of an acute or gradually worsening headache is the
most important symptom indicating an intracranial
complication. Nausea, vomiting, alteration of mental
status, affective changes, seizures, lethargy, and coma
may also be observed. If the frontal lobe is involved,
Infl ammatory Lesions 61
a very limited dissection aimed at restoring the
ventilation of the involved paranasal sinus(es), by
removing only those bony structures (i.e., uncinate process, ethmoid bulla, pneumatized middle
turbinate) which impair the outflow of secretions.
There is no need to perform any stripping of mucosa, which will revert to a normal status within
a short period.
Most orbital complications respond to intravenous broad-spectrum antibiotics within 48–72 h.
According to Younis et al. (2002a), surgery is required when at least one of the following fi ve circumstances is present:
CT evidence of abscess formation
20/60 (or worse) visual acuity on initial evalua-
tion
Severe orbital complications (i.e., blindness or an
Fig. 6.1. Acute bacterial rhinosinusitis. At nasal endoscopy (0°
rigid endoscope), whitish, purulent secretion covers the right
middle turbinate (MT). Nasal septum, NS; inferior turbinate, IT
afferent pupillary refl ex on initial evaluation)
Progression of orbital signs and symptoms despite
therapy
Lack of improvement within 48 h despite maxi-
mum medical therapy
signs and symptoms may be absent, with only mild
personality changes until the infection spreads.
Nasal endoscopy shows an infl amed, congested
mucosa covered by purulent secretions, fl owing
from the ostiomeatal complex and the sphenoethmoidal recess when the entire ethmoid is affected by
the infection (Fig. 6.1). Isolated involvement of the
anterior or posterior compartment of the ethmoid
is suggested by the presence of purulent discharge
into the middle or superior meatus, respectively.
Sometimes, a micropolyposis secondary to the infection can be appreciated. There are no peculiar
endoscopic fi ndings which differentiate an uncomplicated from a complicated acute rhinosinusitis;
therefore, only an accurate clinical evaluation may
alert the physician.
6.2.3
Treatment Guidelines
The treatment of choice of acute rhinosinusitis is
antibiotic therapy. The most frequently used antibiotics for non-complicated rhinosinusitis are
amoxicillin-clavulanate and second generation
cephalosporins for at least 10 days. If the patient
does not improve within 72 h, an alternative antibiotic should be used. In the very rare event medical
therapy fails, microendoscopic surgery, based on a
preoperative CT, is indicated. This may encompass
While in the past orbital complications have
been routinely treated through external procedures, in the last decades microendoscopic surgery
has emerged as the surgical modality of choice for
acute rhinosinusitis with an orbital complication,
particularly in case of subperiosteal or intraorbital abscesses with a medial location (Lusk 1992;
Noordzij et al. 2002; Sobol et al. 2002). Surgical
steps include uncinectomy, anterior and posterior
ethmoidotomy, followed by subtotal removal of the
lamina papyracea to drain the abscess. Conversely,
abscesses located laterally in the orbit require an
external approach. For cavernous sinus thrombophlebitis, other than intravenous broad-spectrum
antibiotics, steroids, and drainage of the sinonasal area infected (generally the sphenoid or the
ethmoid sinus), anticoagulants may be indicated
(Amran et al. 2002).
Treatment of intracranial complications consists
of broad-spectrum intravenous antibiotics crossing
the blood–brain barrier. Surgical treatment is indicated if no improvement is noted within 48 h, provided the patient’s neurologic condition is stable.
Microendoscopic surgery may be employed, apart
from the patients who have obvious CT signs of osteomyelitis of the frontal bone. In this circumstance,
a coronal approach with wide resection of diseased
bone is mandatory. When the posterior wall of the
frontal sinus is also involved and needs to be removed, cranialization is required.
62
6.2.4
Key Information to Be Provided by Imaging
Extent of the disease
Presence of anatomic variants altering the physi-
ologic drainage of paranasal sinuses and favoring
the occurrence of an acute infection
Presence of anatomic variants which may increase
the risk of intraoperative complications
Presence of resorption of sinusal walls, particu-
larly the lamina papyracea and the anterior skull
base fl oor
Presence of abundant scar tissue due to previous
sinus surgery
Identifi cation of complications and assessment of
their extent
6.2.5
Imaging Findings
Acute rhinosinusitis does not require a radiologic study
of the paranasal sinuses because the symptoms reported
by the patient in association with the endoscopic examination are the only diagnostic steps required for making
a correct diagnosis (Phillips 1997).
When an orbital complication is suspected, generally secondary to acute ethmoiditis, CT permits differentiation between edema, phleg mon, and abscess, and
precise identifi cation of the site of the lesion, which is
necessary for proper treatment planning (Hähnel et
al. 1999). CT may discriminate between preseptal cellulitis, subperiosteal infl ammation, and intraorbital
(extra- or intraconal) spread. Involvement of orbital
muscles and posterior extension of the infl ammatory collection towards orbital fi ssures are additional
critical issues, the latter entailing an obvious risk of
intracranial spread.
Preseptal cellulitis (Group 1 according to Chandler
et al. 1970) is confi ned to the anterior compartment
of the orbit (eyelid, periorbital soft tissues). CT shows
thickening of the orbital septum, increased density
of orbital septum and periorbital soft tissues without
involvement of the orbital cavity or exophthalmos
(Oliverio et al. 1995).
Increased density of intraorbital fat tissue is the
hallmark of orbital cellulitis (Group 2 according to
Chandler et al. 1970). It is often observed at the level
of the retrobulbar space amid muscles and optic nerve.
Subperiosteal abscess is located between the inner
surface of the orbital walls and the periorbita (Group
3 according to Chandler et al. 1970) (Fig. 6.2). Both
CT and MR may demonstrate a fl uid collection with
D. Farina et al.
a
b
Fig. 6.2 a,b. Complicated acute rhinosinusitis: subperiosteal
abscess. Axial CT after contrast administration. a Fluid in-
fl ammatory material occupies the left ethmoid labyrinth (as-
terisk). Thickening and increased density of periorbital soft
tissues at the level of medial orbital angle, eyelid, and nasal
pyramid: preseptal edema (arrows). An infl ammatory collection is detected between the lamina papyracea and the medial rectus muscle (arrowheads). b The small gas bubbles in
the upper section contained in the collection is bordered by
a thin hypodense line, probably the periorbita (arrowheads):
subperiosteal abscess. Thickening of the prenasal tissue (black
arrows)
a peripheral enhancing rim. CT better depicts subtle defects of the bony walls adjacent to the abscess
(Yousem 1993). Gas bubbles within the collection
herald the presence of anaerobic agents or indicate
fi stulization from contiguous paranasal cavities.
Abscesses (Group 4 according to Chandler et al.
1970) secondary to ethmoid sinusitis are generally
observed along the lamina papyracea, displacing the
orbit anteriorly and laterally, whereas fl uid collections
complicating frontal sinusitis are located along the superior orbital wall and dislocate the ocular bulb anteriorly and inferiorly. A key point to be ruled out at CT
is intraconal extension of the abscess through a breach
Infl ammatory Lesions 63
of the periorbita. In this case, a precise assessment of
the relationships between the lesion, extrinsic muscles,
ocular bulb, and optic nerve is necessary (Fig. 6.3).
MR better demonstrates further vascular complications, such as superior ophthalmic vein or cavernous
sinus thrombosis (Group 5 according to Chandler
et al. 1970) (Yousem 1993; Oliverio et al. 1995).
The entity of bone changes – perfectly depicted
at CT – is widely variable: intraorbital spread of infl ammation in the absence of detectable defects of the
lamina papyracea can often be observed in pediatric
patients. More aggressive infl ammatory processes
may induce osteitis or osteomyelitis. Both CT and MR
may demonstrate irregular areas of sclerosis – indicating chronic osteitis – as well as bone destruction
with sequestration, typical of active osteomyelitis
(Fig. 6.4).
Overall, CT may provide a correct diagnosis of orbital complication in up to 91% of cases, being signifi cantly more accurate than clinical examination
alone (81%) (Younis et al. 2002c).
Intracranial complications are generally secondary to frontal sinusitis. They are observed even in the
absence of sinus wall defects, as they may be secondary to thrombophlebitis of valveless diploic veins
(Lerner et al. 1995). Imaging is mandatory, in order
to correctly assess the degree of involvement of in-
tracranial structures. In this setting, MR should be
considered the technique of choice, its accuracy being superior to CT, in particular in differentiating dural reaction from epidural/subdural or intracerebral
abscess, and in demonstrating thrombosis of sagittal
or cavernous sinus (Hähnel et al. 1999; Rao et al.
2001; Younis et al. 2002c).
CT fi ndings of meningitis may be unremarkable.
Early signs are represented by mild enlargement of
ventricles and subarachnoid spaces. Large amounts
of infl ammatory exudate may efface subarachnoid
spaces, inducing marked enhancement of the meninges. This is probably related to extravasation of
contrast agent from small vessels or to the presence
of granulation tissue. Dural enhancement is also
demonstrated at MR, on Gd-enhanced SE T1 images,
especially at the level of the falx, tentorium, and convexity (Younis et al. 2002c).
At CT, subdural/epidural abscess is detected as an
extracerebral hypodense fl uid collection with a convex shape, separated from the parenchyma by a thick
and enhancing rim (Fig. 6.5).
The CT appearance of brain abscesses is widely
variable in the different phases of evolution. During
the cerebritic phase, a focal hypodense area may
be observed, characterized by a superfi cially gyriform and deeply granular pattern of enhancement.
abc
Fig. 6.3a–c. Complicated acute rhinosinusitis: from subperiosteal to intraconal abscess. Plain CT scan on the axial plane (a,b);
contrast enhanced CT scan obtained 24 h after surgery (c). Acute rhinosinusitis: maxillary sinus and ethmoid labyrinth are
occupied by infl ammatory secretions. Preseptal edema (PE) and a subperiosteal abscess – bordered by medial rectus muscle
– (arrows) are demonstrated in (b). CT scan performed 24 h after surgery (c) shows a large residual cavity after partial eth-
moidotomy and a breach in the medial orbital wall. Though subperiosteal abscess has been drained, an intraconal infl ammatory
collection has developed behind the eyeball (arrowheads)
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