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Transcript of Ent Trends- Issue 1, July 2009
ISSUE 1 JULY 2009 VOLUME 1
ENT E– NEWSLETTER ON RECENT TRENDS IN ENT
Fungal sinusitis Issue 1
TRYST WITH HISTORY
ALLERGIC FUNGAL
RHINOSINUSITIS
FUNGAL SINUSITIS:
CURRENT TRENDS
RADIOLOGY OF
FUNGAL SINUSITIS
JOURNAL SCAN
QUIZ
� TRYST WITH HISTORY
� FUNGAL SINUSITIS: RECENT TRENDS
� QUIZ
© Dr. Pooja Kataria, New Delhi, July 2009
trends
ForewordForewordForewordForeword
Volume 1 Issue 1 July 2009 Pg2
Dear colleagues,
Being an academician for more than twenty years, I have witnessed
the ever changing scenario of teaching and acquiring knowledge. We
have come a long way from attending lectures, flocking the librar-
ies to now, virtually sitting at home and getting all the information
at click of a button. Shaking hands with the technological advance-
ment and to further our knowledge of Otorhinolaryngology, we have
decided to launch a newsletter. Each issue of this e- newsletter
will focus on a particular topic of clinical or academic importance
and will touch upon everything, from historical aspects to the re-
cent trends. The success of this endeavor will depend on your con-
tributions and feedback. This concept is originated by youngsters
and should be encouraged. I hope that this will receive all your
support and guidance. I wish the editors and authors the best of
luck and congratulate them for their effort.
DR. A. K. AGARWAL Dean and Director Professor ENT, Maulana Azad Medical College
ENT TODAY VOL. 1, ISSUE1. JULY 2009
E- NEWSLETTER ON RECENT
Modern practice of medicine offers vast information on every topic, but on the downside confuses us with multitude of treatment options. Experience coupled with our knowledge on a particular topic gathered from our institutions or otherwise, guides us through the proper management. Keeping abreast with the ongoing research and ever changing thera-peutic guidelines, we have taken upon us the task to compile a newsletter. Our attempt will be to outline the national and international treatment guidelines along with the recent trends on a particular disease, in each issue. Through this e-newsletter, our humble effort is to interact with as many ENT surgeons and expand our knowledge pool with their feedback.
We hope you enjoy reading this issue as much as we did compil-ing it. This issue focuses on the controversial topic of fungal sinusitis and its debatable management. We plan to take out the next issue on some interesting ear topic, may be the illustrious “cochlear implant”:) Since in medicine, there is one rule that there is no rule, inputs from varied sources will lead to enrichment of our skills, particu-larly of those graduates who are in the formative stages of their career. We solicit contributions from as many ENT practitioners, and sincerely hope that this e-newsletter will grow with each passing day.
Volume 1 Issue 1 July 2009 Pg3
E-Mail: [email protected]
Advisor
Dr. A.K. Agarwal
Editorial Board
Pooja Kataria Sumit Mrig Ankush Sayal
History has never fascinated us medicos, but of course we like to know how and when great minds
discovered the techniques and equipment we use today.
The most significant advances in medicine in this century have been the discovery of antibiotics, the
invention of various computerized scans and endoscopy of the various body cavities.
The first revolutionary change in the surgical treatment of the sinuses was the introduction and refine-
ment of endoscopic techniques. The second important development in the modern history of rhinol-
ogy was the introduction of powered instrumentation. Now we are seeing a third turning point, which
is the use of intraoperative image guidance in endoscopic sinus surgery.
Endoscopes are used in many branches of medicine today, so much so, there is no body cavity one
cannot have a look into. The endoscopes used for nasal sinus endoscopy are rigid tubes consisting of
rod lenses. The optical system used has been developed by Prof. H.H.Hopkins has larger viewing an-
gles and transmit brighter light.
Special instruments developed for the purpose are passed alongside the endoscope into the nose
and operations are carried out using key hole surgery principle. Though the idea was conceived and
early work was done by Prof. Messerklinger of Graz, Austria, it is Prof.H.Stammberger who popularized
Endoscopic sinus surgery in the English speaking world. The radical Endoscopic spheno-fronto-maxillo
-ethmoidectomy we do for massive polyps and fungal sinusitis would not fit into the original descrip-
tion of FESS by Dr. Kennely and Prof. Stammberger. Hence it is referred to as Endoscopic Sinus Surgery
(ESS).
The first powered instrument (microdebrider, or soft tissue shaver) was designed and patented by an
Otolaryngologist, Dr. J.C. Urban, in 1969, for use in microscopic ear surgery. Powered instruments be-
came very useful in orthopedic arthroscopic surgery in the 1970s and were used in Otolaryngology-
Head & Neck Surgery in the 1990s, after the introduction of endoscopic techniques made their use
more practical.
Reuben Setliff was the first physician to successfully demonstrate that powered cutting tools could be
used with precision control and safety in the nose and paranasal sinuses in humans. The first Micro-
Debrider was adapted from a tool produced for use in small joint arthroscopy in the wrist and TMJ.
Volume 1 Issue 1 July 2009 Pg 4
Tryst with HistoryTryst with HistoryTryst with HistoryTryst with History
Allergic fungal rhinosinusitis
History:
The combination of nasal polyposis, crust formation, and
sinus cultures yielding Aspergillus was first noted in 1976
by Safirstein who observed the clinical similarity that this
constellation of findings shared with allergic bronchopul-
monary Aspergillosis ( ABPA). In 1981, Millar et al
described five cases of chronic Aspergillus fumigatus
sinusitis in which the sinus exudates appeared histologically
similar to the inspissated bronchial mucus plugs in patients
with ABPA. The authors named the condition “allergic
aspergillosis of the paranasal sinuses”. In 1983, Katzenstein
and colleagues retrospectively reviewed 113 consecutive
surgical histopathologic specimens from chronic sinusitis
surgeries. Seven (6%) were identified as “allergic
aspergillus sinusitis”. Histologically the extramucosal
material was characterized as “allergic mucin”- degenerat-
ing eosiniphils, desquamated respiratory epithelial cells, and
Charcot-Leyden crystals. Fungal stains showed fungal
hyphae in the allergic mucin, but not in the mucosa. There
was no histologic evidence for tissue invasion by the fungi.
Many others also reported identical findings thereafter and
more cases have been described since then, not only with
Aspergillus spp. but with other fungi such as Bipolaris,
Alternaria, Curvilaria, and Exserohilum.
Allergic fungal sinusitis (or allergic fungal rhinosinusitis;
AFRS) is a term introduced by Robson et al in 1989.
Comparision to ABPA AFRS is believed to have an etiology similar to that of
ABPA. As more is understood about the pathophysiology of
ABPA than AFRS, the former is discussed as possible
model for the processes involved in AFRS.
These diseases are initiated by immunological reactivity to
antigens of Aspergillus species in the sinuses or bronchi of
affected individuals; and may be components of a wide
spectrum of compartmental allergic manifestations in the
respiratory tract.
Pathophysiology:
The exact pathophysiology of AFRS remains a matter of
conjecture for which several theories have been offered.
One popular theory proposed by Manning and col-
leagues is based on the assumption that AFRS exists as
nasal correlate of allergic bronchopulmonary aspergillo-
sis, of the disease.
It is depicted in a diagrammatic representation on the
next page. At some point this cycle becomes self-
perpetuating and results in the eventual product of this
process: allergic mucin; accumulation of which obstructs
the involved sinuses and propagates the process.
Certain unanswered questions regarding this theory • If AFRS is an IgE mediated disease, then why does it
predominantly occur in a unilateral fashion
• Why does fungal specific IgE remain elevated after
prolonged fungal immunotherapy when normally it
should decrease?
Hence, although it remains clear that the eosinophils play
an important role in the development of AFRS; eosino-
philic inflammation may occur as a final common path-
way in response to a number of different inflammatory
starting points.
Clinical presentation:
Patients typically present with
• gradual nasal airway obstruction and production of
semisolid nasal crusts that, on inquiry, match the
gross description of allergic fungal mucin.
• The development of nasal obstruction may have been
so gradual that the patient is unaware of its presence.
• Pain is uncommon among patients with AFRS and
suggests the concomitant presence of a bacterial
rhinosinusitis.
• Patients with AFRS are atopic but generally have
been unresponsive to antihistamines, intranasal corti-
costeroids, and prior therapy. The use of systemic
corticosteroids may produce some relief of symp-
toms, but relapse typically follows completion of
therapy.
Physical findings on examination, range from nasal
obstruction to gross facial disfigurement and orbital or
ocular abnormalities.
Volume 1 Issue 1 July 2009 Pg 5
Initiation of inflammatory cascade leading to AFRS is a multifactorial event
-
-mucostasis -Fungal exposure -Atopy
-anatomic anomaly -T-lymphocyte
susceptibility
P.S: block arrows indicating points of intervention to break the cycle
Inflammation Eosinophilic inflammation
MBP, ECP, etc)
Fungal Proliferation
Antigenic exposure
Inflammatory trigger
Gel & Coombs TypeI & III
T– Cell
Others
Edema Obstruction
Stasis
Decreased ventilation
Allergic mucin
Anatomic factors
Immunotherapy Steroids
Bacterial
infection
Exposure Nasal saline irrigation
s u r g e r y
Volume 1 Issue 1 July 2009 Pg 6
Local Environmental Genetic
Radiologic findings:
Soft tissue attenuation areas with internal hyperdensity are seen on non-contrast CT scans. These findings are although
not specific for AFRS, but they are relatively characteristic and provide preoperative information supportive of the
diagnosis of AFRS. The ethmoid sinus is the most commonly involved sinus, whereas the lamina papyracea is the most
common bone to exhibit demineralization. The presence of accumulations of heavy metals (iron, manganese) and
calcium salt precipitation within the inspissated allergic mucin is the most likely cause of these radiologic findings.
On MRI, presence of hypointense central T1 signal, central T2 signal void, and increased peripheral T1/T2 enhance-
ment is highly specific for AFRS as compared with other forms of fungal sinusitis. The high protein and low water
concentration of allergic fungal mucin, coupled with the high water content within surrounding edematous paranasal
sinus mucosa, gives rise to specific MR characteristics.
Laboratory findings:
Immunologic tests: Total IgE levels is a useful indicator of AFRS clinical activity. It is generally elevated to more than
1000 U/ml. Patients usually demonstrate positive skin test and in vitro ( RAST) responses for both fungal and nonfungal
antigens.
Histology of allergic fungal mucin: Allergic mucin is the hallmark of this disease. Grossly, it is thick, tenacious, and
highly viscous in consistency; its color may vary from light tan to brown or dark green. Histologic examination reveals
branching noninvasive fungal hyphae within sheets of eosinophils and Charcot-Leyden crystals.
Culture of fungi: Fungal cultures provide some supportive evidence helpful in diagnosis and subsequent treatment of
AFRS, but it is important to realize that the diagnosis of AFRS is not established or eliminated on the results of these
cultures. Various species of fungi have been cultured including Bipolaris, Curvalaria, Aspergillus, Exserohilum and
Alternaria.
Volume 1 Issue 1 July 2009 Pg 7
Volume 1 Issue 1 July 2009 Pg 8
Diagnosis:
Although certain signs and symptoms , as well as radiographic, intraoperative, and pathologic findings, may
cause the physician to suspect allergic fungal sinusitis, no standards had been defined for establishing the
diagnosis.
Parameters which enhanced the index of suspicion were as stated by Waxman et al (laryngoscope 1987):
(1)Young adults, (2)Recurrent polyposis, (3)History of asthma, (4)Multiple affected sinuses, (5)History of poor
response to medical management, (6)Multiple surgical procedures, (7)Thick inspissated intracavity mucus, (8)
Atopic patients with nasal polyps.
Many others used the combination of radiologic, laboratory and histologic parameters to distinguish AFRS from
other forms of rhinosinusitis.
In 1996, Bent and Kuhn laid down the diagnostic criteria, which are the most widely accepted.
These are as follows:
• Type I hypersensitivity confirmed by history, skin tests, or serology
• Nasal polyposis
• Characteristic CT signs- serpiginous areas of increased attenuation within the sinus cavity.
• Eosinophilic mucin without fungal invasion
• Positive fungal stain
• Asthma
• Unilateral predominance
• Radiographic bone erosion
• Positive fungal culture
• Charcot-Leyden crystals
• Peripheral eosinophilia
Of the criteria mentioned, allergic or eosinophilic mucin and atopy (Type I hypersensitivity) are considered
the most diagnostic of all.
Treatment:
Long term control of AFRS requires both elimination of fungal antigen by surgical therapy and control of its
recurrence by medical therapy. As early as 1979, it was established by McGuirt et al, that the treatment of
paranasal sinus aspergillosis is surgical and the key to which is the removal of diseased mucosa and aeration
and drainage of the involved sinus. Previously, procedures such as open antrostomies, intranasal sphenoeth-
moidectomies, lateral rhinotomies, and craniofacial resection were done. More radical procedures were also
being done because the clinical and radiographic evidence of invasion into adjacent spaces, were interpreted
as evidence of malignancy or invasive fungal disease. And hence, more morbidities and mortalities were en-
countered.
Changes have evolved in both medical and surgical arms of therapy. Radical surgery for AFRS has given
way to more conservative, tissue-sparing techniques, “conservative, but complete” as proposed by Mabry et
al.
M
A
J
O
R
M
I
N
O
R
Volume 1 Issue 1 July 2009 Pg 9
Preoperative therapy: It is accepted that to decrease intranasal inflammation and nasal polyp volume,
systemic prednisolone (0.5 to 1.0 mg/kg/day) should be started 7 days before surgery. Preoperative antibiotics
should also be instituted because of the frequency of concomitant postobstructive bacterial sinusitis.
Goals of surgical treatment:
• Surgery should result in complete extirpation of all allergic mucin and fungal debris, reducing or eliminating the
antigen-inciting factor within the atopic individual. Polyps can provide an important intraoperative role by serving as a
marker of disease.
• Second goal of the surgery is to provide permanent drainage and ventilation of the affected sinuses while preserv-
ing the integrity of underlying mucosa.
• Final goal of the surgery is to provide postoperative access to the previously diseased areas, as even under ideal
conditions, some residual fungus may remain in situ inciting recurrence if not controlled postoperatively.
Medical therapy:
Corticosteroids: Topical corticosteroids are accepted as standard therapy in postoperative treatment of AFRS, but they
possess a limited benefit before surgery because nasal access is restricted. Kupferberg et al refined the endoscopic
follow-up into a staging system, which allows closer control of the mucosal response to medical management, that is,
oral steroids.
Oral prednisone (0.4 mg/kg per day)- 4 days
reduction by 0.1 mg/kg/day
in cycles of 4 days
Oral prednisone 20 mg/day, or 0.2 mg/kg/day (whichever is greater)- 1 month
Oral prednisone 0.2 mg/kg/day
monthly follow-ups with nasal endoscopy
and serum IgE levels
Dose adjusted based on maintenance of Stage 0- 4 months
Oral prednisone at 0.1 mg/kg/day plus intranasal steroid
spray at triple dose- one spray in each nostril 3 times daily
patient maintained at Stage 0 for 2 months
Oral prednisone tapered to zero, intranasal steroid spray continued for 1 year
Follow up till 5 years : endoscopy and serum IgE levels monthly for 6 months, bimonthly for 3-5 years.
STAGING SYSTEM BASED ON
ENDOSCOPIC FINDINGS
0
no mucosal edema or allergic
mucin
I
mucosal edema with or without
allergic mucin
II
polypoid edema with or without
allergic mucin
III
sinus polyps with fungal debris or
allergic mucin
Volume 1 Issue 1 July 2009 Pg 10
Antifungals: In vitro studies of use of oral antifungals show promising results in AFRS, but in vivo studies
are pending. However, the expense, limited available data, and potential drug-related morbidity of systemic antifungal
therapy may limit the usefulness of this form of treatment for noninvasive fungal disease. Topical application of anti-
fungal agents may hold some benefit in the control of postoperative recurrence. A study by Fenna et al (Laryngoscope
February 2009), examined the effect of topical Amphotericin B on inflammatory markers in patients with chronic
rhinosinusitis, and concluded that it has no significant effect on activation markers of nasal inflammatory cells.
Immunotherapy: The similarity between AFRS and ABPA led to a theoretical concern that immunotherapy using spe-
cific fungal antigens in patients with either of these diseases might incite further allergic reactions by adding to the pa-
tient’s fungal antigenic stimulus and possible exacerbation of immune complex development and deposition. However,
in the case of AFRS, surgery theoretically allows removal of the inciting fungal load from the paranasal sinuses and
hence, immunotherapy after surgery may be beneficial rather than harmful.
Surgical exenteration of sinuses + confirmation of diagnosis
Allergy evaluation and testing( RAST and quantitative skin tests) for relevant fungal
and non-fungal antigens appropriate for the area.
Avoidance measures Treatment protocol explained to patient
Pharmacotherapy Informed consent
adjusted
One vial prepared of all positive non-fungal antigens
Second vial of all positive fungal antigens
(vial test with each performed)
Weekly immunotherapy placing one injection from each vial in a different arm
(for accurate recognition of cause of any local reactions)
dose advancement as tolerated,
patient observed for local reactions,
adverse changes in nasal signs/symptoms,
adjustment of medical management based on endoscopic examination for
re-accumulation of allergic mucin or reformation of polyps
Immunotherapy continued for about 3-5 years.
Follow-up
• Postoperatively for at least 3 years.
• Postoperative treatment with oral corticosteroids, topical steroid nasal sprays, antihistaminics and deconges-
tants (if indicated), anti-leukotrienes ( may be!?) and nasal sinus lavage are followed. Allergen immunother-
apy if available is started as detailed.
• Postoperative follow-up includes monitoring changes in clinical status and serial measurements of total
serum IgE which in-turn guide the dose changes of oral corticosteroids and addition of antibiotics, if needed.
Progressive decrease in total serum IgE levels is a good prognostic sign, that encourages prednisone taper-
ing according to protocol. A progressive rise in total serum IgE levels during follow-up, or a rise that occurs
repeatedly during attempted prednisone tapers should alert the clinician to probable recurrent surgical AFRS
and the need for additional surgical evaluation.
Goals to be achieved
• To keep clinical rhinosinusitis minimal and forestall the need for recurrent sinus surgery.
• To taper oral corticosteroids without significant worsening of condition.
• To minimize treatment related steroid side effects.
Volume 1 Issue 1 July 2009 Pg 11
Author details:
Dr. Pooja Kataria, Specialist, ESI Hospital, Basaidarapur, New Delhi.
Volume 1 Issue 1 July 2009 Pg 12
Fungal sinusitis: current trends
The following section will give you a brief overview of what’s latest in management of fungal sinusitis. The following section will give you a brief overview of what’s latest in management of fungal sinusitis. The following section will give you a brief overview of what’s latest in management of fungal sinusitis. The following section will give you a brief overview of what’s latest in management of fungal sinusitis. We will try to highlight newer, amazing discoveries and tickle your brains to explore the topics in We will try to highlight newer, amazing discoveries and tickle your brains to explore the topics in We will try to highlight newer, amazing discoveries and tickle your brains to explore the topics in We will try to highlight newer, amazing discoveries and tickle your brains to explore the topics in
detail :)detail :)detail :)detail :)
The classification which is currently being followed for fungal sinusitis is proposed by de
Shazo et al:
AND ONGOING RESEARCH
Syndrome Common
causes
Host character-
istics
Associated con-
ditions
Histopathologi-
cal findings
Clinical presen-
tation
Treatment Prognosis
Allergic fungal
rhinosinusitis
Bipolaris
Species, Curvu-
laria lunata &
Aspergillus
fumigatus
Immunocompe-
tent, frequently
atopic
Chronic
rhinosinusitis,
nasal polyps
Eosinophil-rich
mucoid material
(allergic mucin)
Chronic pansi-
nusitis nasal
polyps, prop-
tosis or eye–
muscle entrap-
ment in children
Debridement,
aeration, oral
and topical cor-
ticosteroids, ?
immunotherapy
Recurrence
common
Sinus fungal
ball
(mycetoma)
A. fumigatus
and A. flavus
Immunocompe-
tent
Chronic
rhinosinusitis Dense accumu-
lation of fungal
elements in a
mucoid matrix
Rhinosinusitis
( often U/L),
Nasal obstruc-
tion, green-
brown nasal
discharge
Debridement,
aeration, anti-
fungal agents
not required
Excellent
Acute invasive
fungal
rhinosinusitis
Mucorales and
Aspergillus
Immunocom-
promised, rarely
immunocompe-
tent
Diabetes melli-
tus, malignant
conditions,
Immunosuppres-
sive therapy
Fungal elements
in mucosa, sub-
mucosal, blood
vessels or bone,
extensive tissue
necrosis
Fever, cough,
crusting of nasal
mucosa, epis-
taxis, headache,
mental status
change
Radical debride-
ment until his-
tologically nor-
mal tissue is
evident, antifun-
gal agents,
treatment of
underlying con-
ditions
Fair when dis-
ease is limited
to sinus, poor
with intracranial
involvement
Chronic inva-
sive fungal
rhinosinusitis
A. fumigatus Immunocompe-
tent
Diabetes
mellitus
Necrosis of mu-
cosa, submuco-
sal, bone &
blood vessels,
low grade
inflammation
Orbital apex
syndrome,
nerve palsy
Radical debride-
ment, antifungal
agents
Variable, long-
term survey
required
Granulomatous
invasive fungal
rhinosinusitis
A. flavus Immunocompe-
tent
None Granulomas
with multinucle-
ate giant cells,
histiocytes
Unilateral prop-
tosis
Debridement,
aeration, and
antifungal
agents
Good, but dis-
ease can recur
Volume 1 Issue 1 July 2009 Pg 13
Advances in treatment
The triazoles are newer, and are less toxic and more effective:
• Fluconazole
• Itraconazole
• Ravuconazole
• Posaconazole
• Voriconazole
Newer recommendations for treatment of invasive aspergillosis:
• Voriconazole as primary therapy in most patients
• Liposomal amphotericin—alternative therapy in some patients
• Options for salvage therapy; dependent on prior therapy, host factors, dosing considerations; potential
agents: posaconazole, itraconazole, echinocandins, lipid amphotericin formulations.
• Prophylaxis with posaconazole can be recommended in high risk patients (Walsh TJ, et al. Clin Infect Dis
2008;46:327-60)
Role of topical antifungals:
• The Mayo clinic has found that 6 months of irrigation with Amphotericin (250 micrograms/ml) showed 75 % im-
provement not only in the amount of mucosal thickening on the CT scan as well as endoscopic scores.
• The Mayo clinic is now recommending a concentration of 100 micrograms/ml.
• Although when given intravenously there are serious side effects with Amphotericin B, topically it causes minimal
problems.
• Some patients seem to respond to treatment with oral antifungals, including Sporanox, Diflucan, and possibly
Nizoral.
Intranasal application of amphotericin B. Patients apply 20 mL of antifungal solution into each nostril using a bulb syringe. Arrow shows hand movement to accomplish suc-cessful application of the antifungal drug from me-dial (ethmoid) to lateral
Volume 1 Issue 1 July 2009 Pg 14
Advances in endoscopic sinus surgery
Otolaryngologists have employed computer-aided surgery, or image-guided surgery, over the past two decades to en-
hance surgeon’s confidence, allow more thorough surgical dissections and possibly reduce the complication rate of
endoscopic sinus surgery. Computer-aided surgery utilizes preoperative imaging to provide real-time localization of
surgical instruments in the surgical field. Although computer-aided surgery originated in the neurosurgical realm, oto-
laryngologists soon appreciated that this technology could assist in identifying critical orbital or intracranial structures
surrounding the paranasal sinuses, and potentially aid in decreasing complications. In this article, the history of image-
guidance systems and their application to surgery of the paranasal sinuses and skull base will be reviewed. The compo-
nents of computer-aided surgery systems and the currently available technologies for surgical instrument tracking are
discussed, as well as the advantages and disadvantages of each of the tracking technologies.
• The term "stereotactic" was coined from Greek and Latin roots meaning "touch in space”.
• A colorful term for this surgery is “neuro-navigation”.
• Use images of the paranasal sinusis and the brain to guide the surgeon to a target within the brain by utilizing the
stereotactic principle of co-registration of the patient with an imaging study.
Frameless stereotactic surgery
• Based on the principle of the global positioning system.
• Relies on anatomical landmarks on the patient’s head and/or fiducial markers (temporary skin markers) which are
taped to the scalp before the brain is imaged.
• In the operating room the orientation of these markers is used to register the computer containing the brain im-
ages.
• References this coordinate system with a parallel coordinate system of the three-dimensional image data of the
patient that is displayed on the console of a computer-workstation so that the medical images become point-to-
point maps of the corresponding actual locations.
Volume 1 Issue 1 July 2009 Pg 15
IMAGE GUIDED SURGERY
Image-guided surgery (IGS), also known as surgical navigation, is a specific technology that visually correlates intraop-
erative anatomy with preoperative CT scans. Often IGS is considered to be analogous to the global position system
(GPS), a technology that permits individuals to show their relative position on computer-generated map. For IGS, the
preoperative CT scan serves as the map, and the intraoperative tracking system is similar to the satellites and devices
that are used for GPS.
During nasal surgery, an IGS system will show the position of an instrument tip relative to the preoperative CT scan
images. Thus, the surgeon is better able to correlate intraoperative anatomy with the preoperative CT scans.
Image-guided surgery may be helpful in situations
• where complications might otherwise occur because of difficulty with recognizing the usual anatomy.
• in case of frontal sinus disease,
• in patients who need to be re-operated.
The CT scan images represent the coronal and reconstructed sagittal and axial views. The probe is at the level of the
middle turbinate. As you can see, the cross-hairs indicate exactly where the probe is on each of the coronal, sagittal
and axial views.
Volume 1 Issue 1 July 2009 Pg 16
The use of navigation for ENT procedures has improved patient outcomes. Its main uses are :
• Revision sinus surgery
• Distorted sinus anatomy of development, postoperative, or traumatic origin
• Extensive sino-nasal polyposis
• Pathology involving the frontal, posterior ethmoid and sphenoid sinuses.
• Disease abutting the skull base, orbit, optic nerve or carotid artery
• CSF rhinorrhea or conditions where there is a skull base defect
• Benign and malignant sino-nasal neoplasms.
The primary advantages to using our navigation solutions for FESS include:
• Procedures are much less invasive than open surgical operations.
• Precision is greater, resulting in lower risk to the patient.
• Patient discomfort is minimal.
• Procedure recovery time is shorter.
ENT Procedures that can be done using the navigation system:
• Transphenoidal procedures
• Maxillary antrostomies
• Ethmoidectomies
• Sphenoidotomies/ sphenoid explorations
• Turbinate resections
• Frontal sinusotomies
The ENT system is not only significantly more complex, it has to be more intuitive, as the cranial anatomy with all its
sinuses, and nerves, and arteries and veins, is much more intricate.
The system's navigation coordinates are provided by the Patient Registration Mask.
Volume 1 Issue 1 July 2009 Pg 17
BALLOON SINOPLASTY
• Sinus guide catheter is introduced into the nasal cavity under endoscopic visualization, sinus guide wire is intro-
duced through the catheter and advanced into the target sinus.
• The sinus balloon catheter is introduced over the sinus guide wire and is positioned across the blocked ostium.
The position of the balloon catheter is confirmed, and the balloon is gradually inflated to remodel the nar-
rowed or blocked ostium.
• The balloon catheter is then deflated and removed, leaving the ostium open.
Author details:
Dr. Sumit Mrig, Senior Resident, Department of ENT & Head and Neck surgery, Maulana Azad Medical
College, Lok Nayak Hospital & Associated Hospitals.
Volume 1 Issue 1 July 2009 Pg 18
a b
Non-contrast CT image (a) in a patient with
diabetic ketoacidosis with acute fungal sinusi-
tis shows hypoattenuationg soft tissue within
the nasal cavity & left ethmoid & frontal si-
nuses.
Intracranial extension is clearly evident in this
contrast enhanced T1W MRI image (b).
RADIOLOGYRADIOLOGYRADIOLOGYRADIOLOGY
In ENT practice, CT offers great help not only in diagnosis but also in planning of sinus surgery, where half the exercise is already per-
formed before actually starting the surgery by reconstructing 3D images of sinuses in the head of the operating surgeon.
The radiologic characteristics of fungal sinusitis are very specific and aid in diagnosis and also guide towards the mode and the tim-
ing of appropriate treatment. Understanding the different types of fungal sinusitis and knowing their particular radiologic features
allows the radiologist to play a crucial role in alerting the clinician to use appropriate diagnostic techniques for confirmation. Prompt
diagnosis and initiation of appropriate therapy are essential to avoid a protracted or fatal outcome.
Acute Invasive Fungal Sinusitis Acute invasive fungal sinusitis is seen predominantly in immuno-compromised patients or those with poorly controlled diabetes.
Along with sinuses, nasal cavity is a frequent site of infection, with middle turbinate accounting for two-thirds of positive biopsy
results. Angioinvasion and hematogenous dissemination are frequent with a mortality ranging from 50-80%.
Hypoattenuating mucosal thickening or soft-tissue attenuation within the lumen of the involved paranasal sinus and nasal cavity is
seen on NCCT. There is a predilection for unilateral involvement of the ethmoid and sphenoid sinuses. Rapid, aggressive bone de-
struction of the sinus walls is seen with intracranial and intraorbital extension of the inflammation. However, bone erosion may
even be absent or very subtle and fungi tend to extend beyond the sinuses, along the blood vessels. Other complications include
cavernous sinus thrombosis, carotid artery invasion, occlusion, or pseudoaneurysm with resulting cerebral infarct and hemorrhage.
Whereas CT is better to assess for bone changes, MR imaging is superior in evaluating intracranial and intraorbital extension of the
disease. Obliteration of the periantral fat is a subtle sign of extension beyond the maxillary sinus & should be specifically looked for.
Leptomeningeal enhancement may be seen with intracranial invasion and with progressive infection, adjacent cerebritis, granulo-
mas, and abscess formation may be seen. Intracranial granulomas appear hypointense on both T1- and T2-weighted images with
minimal enhancement on contrast enhanced images.
Chronic Invasive Fungal Sinusitis
It usually occurs in immunocompetent individuals; however those with diabetes or a low level of immunosupression are susceptible.
Patients usually have a history of chronic rhinosinusitis with a persistent & recurrent disease. Noncontrast CT reveals a hyperattenu-
ating soft-tissue collection within one or more paranasal sinuses. Mottled lucencies or irregular bone destruction may be seen in the
paranasal sinuses. There may also be sclerotic changes in the bony walls of the affected sinuses representing chronic sinus disease.
Volume 1 Issue 1 July 2009 Pg 19
a
b
c
There is decreased signal intensity on T1-weighted MR images and markedly decreased signal intensity on T2-weighted images.
Infiltration of the periantral soft tissues about the maxillary sinus is an indicator of invasive disease. Invasion of adjacent structures
such as the orbit, cavernous sinus, and anterior cranial fossa may lead to epidural abscess, parenchymal cerebritis or abscess,
meningitis, cavernous sinus thrombosis, osteomyelitis, mycotic aneurysm, stroke, and hematogenous dissemination. Cranial nerve
palsies occur with perineural spread. It may be mass like and differentiation from a malignancy may not be possible on imaging
with destruction of the sinus walls and extension beyond the sinus.
Chronic invasive fungal sinusitis:
(a) Clinical photograph of the patient showing perforation of the hard palate.
(b) Coronal and T2W image showing left maxillary and ethmoid sinusitis . There is destruction of nasal turbinates, ethmoidal septae and
hard palate forming an oro-nasal fistula (arrow).
(c) Coronal post gadolinium showing a fungal granulomas with peripheral enhancing rim in left cavernous sinus & evidence of perineu
ral spread with thickened enhancing mandibular division of trigeminal nerve coursing through the widened foramen ovale (black arrow)
Chronic Granulomatous Invasive Fungal Sinusitis
This form primarily is primarily found in Africa & Southeast Asia. Individuals are generally immunocompetent & disease is charac-
terised by formation of noncaseating granulomas in the tissues. Cross-sectional imaging findings are reported to be similar to
those of chronic invasive fungal sinusitis. They may mimic an invasive mass lesion, with descriptive findings difficult to distinguish
from those of a malignant neoplasm invading the paranasal sinuses, orbital soft tissues, infratemporal fossa, and skull base.
Allergic Fungal Sinusitis
Allergic fungal sinusitis is the most common type of fungal sinusitis & underlying cause is thought to be a hypersensitivity reaction
to certain inhaled fungal organisms. It is characterised by the presence of “allergic mucin”, a yellow green inspissated mucus
which contains eosinophils & Charcot-Leyden crystals. Allergic fungal sinusitis usually occurs in younger individuals that are im-
munocompetent, and often have a history of atopy. Involvement of multiple sinuses is a rule. Disease tends to be bilateral with a
frequent nasal component. The majority of the sinuses show near-complete opacification and are expanded. Noncontrast CT dem-
onstrates hyperattenuating allergic mucin within the lumen of the paranasal sinus. T1W images may reveal high signal intensity or
mixed low, intermediate, and high signal intensity in these patients. There is characteristic low signal intensity or signal void on T2-
weighted images, which is attributed to a high concentration of various metals such as iron, magnesium, and manganese concen-
trated by the fungal organisms.
Volume 1 Issue 1 July 2009 Pg 20
The T2 signal void is also attributed to a high protein and low free-water content of the allergic mucin. The inflamed mucosal lining
is relatively hypointense on T1-weighted images and hyperintense on T2-weighted images and demonstrates enhancement after
intravenous administration of gadolinium contrast material. There is no enhancement in the center or in majority of the sinus con-
tents, which distinguishes this condition from neoplastic entities. Although the condition is not considered invasive, if left un-
treated, the involved sinuses expand and there is smooth bone erosion with subsequent intracranial or intraorbital extension and
resulting cranial or orbital symptoms. Intracranial extension is usually limited by the dura to the extradural space.
Fungus Ball Fungus ball appears as a mass within the lumen of a paranasal sinus and is usually limited to one sinus. The maxillary sinus is the
most commonly involved sinus. A fungus ball typically appears hyperattenuating at noncontrast CT due to dense matted fungal
hyphae & may demonstrate punctuate calcifications. The bony walls of the sinus may be sclerotic and thickened or expanded and
thinned with focal areas of erosion from pressure necrosis. The fungus ball is hypointense on T1-weighted and T2-weighted im-
ages owing to the absence of free water. Calcifications and paramagnetic metals such as iron, magnesium, and manganese also
generate areas of signal void on T2-weighted images.
Author Details:
Dr. Vaibhav Jain, Consultant, Department of Radiology, Max Hospital
Pitampura, New Delhi.
a b
c d
Allergic fungal sinusitis:
Axial unenhanced CT scans (a,b) show expan-
sion of and increased attenuation in the ante-
rior ethmoid, posterior ethmoid, sphenoid, and
frontal sinuses bilaterally. There is characteristic
hyperattenuating material within these sinuses
(black arrows). Note also the smooth thinning of
the posterior wall of the left frontal sinus (white
arrows in b).
On MRI (same patient) unenhanced T1-
weighted images (c) show characteristic high
signal intensity within the left maxillary, left
posterior ethmoid, and sphenoid sinuses
(arrows in c). Corresponding T2-weighted MR
images (d) show marked low signal intensity
within the left maxillary, left posterior ethmoid,
and sphenoid sinuses (arrows in d).
Volume 1 Issue 1 July 2009 Pg 21
JOURNAL SCANJOURNAL SCANJOURNAL SCANJOURNAL SCAN
de Shazo RD, Chapin K, Swain RE. Fungal sinusitis. New England Journal of Medicine. 1997; 337:
254-9.
Katzenstein AL, Sale SR, Greenberger PA. Allergic Aspergillus sinusitis: a newly recognized form of si-
nusitis. Journal of Allergy and Clinical Immunology. 1983; 72: 89-93.
Waxman JE, Spector JG, Sale SR, Katzenstein AL. Allergic Aspergillus sinusitis: concepts in diagnosis
and treatment of a new clinical entity. Laryngoscope. 1987; 97: 261-6.
Bent 3rd JP, Kuhn FA. Diagnosis of allergic fungal sinusitis. Otolaryngology and Head and Neck Sur-
gery. 1994; 111: 580-8.
Mabry RL. Allergic and infective rhinosinusitis:differential diagnosis and interrelationship. Otolaryngol-
ogy and Head and Neck Surgery. 1994; 111: 335-9.
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Volume 1 Issue 1 July 2009 Pg 22
For answers, click on the link below:
http://enttrends.webs.com/
1. The best confirmation of the diagnosis of AFRS requires:
A. a positive fungal culture from the nose
B. A positive fungal culture from the sinus.
C. An elevated total serum IgE
D. Positive surgical sinus histopathology.
E. Positive fungal specific precipitins.
2. The following are true regarding the treatment and follow-up of patients with AFRS except:
A. directional trending of total serum IgE level can be prognostic
B. Current research indicates oral antifungal drugs are effective as adjunctive treatment
C. Amphotericin B is generally contraindicated
D. oral corticosteroids have been found to decrease both symptoms and time to surgical recurrence
E. Patients should be co-managed by both medical and surgical specialists.
3. Which of the following statements regarding fungal sinusitis is/are correct:
A. Bone destruction or extrasinus spread on imaging is essential for diagnosing invasive form.
B. CT scan is the first modality of choice in such patients.
C. Allergic type does not show bone destruction or intraorbital/intracranial spread.
D. Intraorbital & intracranial extension is best depicted on thin slice axial & coronal CT.
E. Loss of periantral fat pad is a sensitive marker for invasive variety.
4. Match the following radiological descriptions to the most probable type of fungal sinusitis:
A. Mixed low & hyperattenuating material in left maxillary sinus on CT with tiny calcific specks.
B. A diabetic with complaints of nasal obstruction & discharge for four months, with recent onset
proptosis showing hyperattenuating soft tissue opacification of left ethmoid & maxillary sinuses,
erosion & sclerosis of maxillary sinus walls & orbital cellulitis on CT.
C. Bilateral frontal, anterior ethmoid & posterior ethmoid sinus involvement with hyperintense mate-
rial on T1W and hypointense on T2W images, with mild expansion.
D. T2 hyperintense mucosal thickening in maxillary, ethmoid and sphenoid sinuses with lack of visuali-
zation of flow void of left intracavernosal ICA.
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