To assess the usefulness of CT images for the diagnosis of suspected odontogenic maxillary sinusitis,. 52 patients with maxillary sinusitis who had received CTÂ ...
Original Articles
Usefulness of CT Images for Diagnosis of Odontogenie Maxillary Sinusitis
Tohru KURABAYASHI, D.D.S., Ph.D., Mizue IDA, D.D.S., Ph.D., Norio YOSHINO, D.D.S., Ph.D., Akiko HOSOKAWA, D.D.S., Takehito SASAKI, D.D.S., Ph.D., Junichi ISHII, D.D.S., Ph.D.*, Toyoko KISHI, D.D.S., Ph.D.** and Mikio KUSAMA, D.D.S., Ph.D.** Department of Dental Radiology and Radiation Research, Tokyo Medical and Dental University, Tokyo, Japan (Director : Professor Takehito SASAKI) *1st Department of Oral and MaxillofaciaI Surgery, Tokyo Medical and Dental University, Tokyo, Japan (Director : Professor Teruo AMAGASA) **2nd Department of Oral and Maxillofacial Surgery, Tokyo Medical and Dental University, Tokyo, Japan (Director : Professor Shouji ENOMOTO) (Received : April 17, 1995,
Revision received : July 3, 1995, Accepted : Aug. 4, 1995)
Key Words : Computed tomography, Sinusitis, Paranasal sinuses CT
To assess the usefulness of CT images for the diagnosis of suspected odontogenic maxillary sinusitis, 52 patients with maxillary sinusitis who had received CT examination were retrospectively analyzed. Maxillary sinus ostium was established on coronal CT images in 20 out of 55 lesions in those 52 patients. However, a considerable number of patients who had i n f l a m m a t o r y disease not only in the maxillary sinus but also in o t h e r p a r a n a s a l sinuses (38/55)or in the nasal meatus (34/55) were included in those 52 patients. Concerning the opening of the ostium, the clinical diagnosis is frequently different from the diagnosis made using CT. The CT findings of the maxillary sinus ostium, nasal meatus and o t h e r paranasal sinuses were thus i m p o r t a n t in p l a n n i n g the t r e a t m e n t for p a t i e n t s with maxillary sinusitis in dentistry, as in otorhinolaryngology. Oral Radiol. V o t l l No.2 1995 ( 7 1 ~ 8 0 )
Introduction The goal of treatment of maxillary sinusitis secondary to nasal infections should be the restoration of normal mucociliary
drainage and ventilation t,4). Accordingly, the importance of the diagnosis of ostiomeatal complex such as maxillary sinus ostium, which makes up mucociliary drainage path2~
(71)
ways of the paranasal sinuses, was recognized earlier in otorhinolaryngology% considerable
number
of
studies
A
Table 1
Age and gender distribution of the patients Age (yrs) Male Female Total
which
10 19 20--29 30--39 40--49 5O 59 60 69 70 79 Total
evaluated the usefulness of CT examination in the diagnosis have been reported in the field of otorhinolaryngologya'4'6 ~), and the number of CT examinations for sinusitis has recently markedly increased4'%
2 9 7 3 7 3 1 32
2 15 10 7 10 7 1 52
6 3 4 3 4 20
On the other hand, patients with maxillary sinusitis who consult a dentist or oral surgeon generally have a chief complaint of pain or discomfort in the upper molar region,
sis
of
suspected
odontogenic
maxillary
and a considerable number of such cases are
sinusitis in dentistry. The result is discussed
suspected to have odontogenic maxillary
with respect to dental treatment planning
sinusitis TM. Odontogenic maxillary sinusitis
compared to that in otorhinolaryngology.
is often caused by periapical abscess, extensive marginal periodontitis, and perforation of the sinus floor at the time of dental extractionla-17L In contrast with sinusitis of
P a t i e n t s and m e t h o d s
1. Patients Fifty-two
patients
who received CT
nasal origin, dental treatment is required 16,1r/.
examination in our department from January
However, the disease may extend to occlude
1991 to December 1992 and who were either
the ostium and involve the other paranasal
clinically or pathologically diagnosed with
sinuses18'~%
Dental treatment alone is no
maxillary sinusitis were included in this
longer effective in such cases and treatment
study. Of those patients, 49 had unilateral and
is needed which reestablishes adequate drain-
3 had bilateral maxillary sinusitis (total of 55
age, in a manner similar to sinusitis of nasal
maxillary sinuses).
origin it).
distribution of the patients are shown in
Thus,
distinguishing
"genuine
odontogenic maxillary sinusitis" from other
Table
1.
The age and gender
Pathological
diagnoses
were
types of sinusitis is important to establish the
obtained by a surgery or a biopsy in 13
treatment plan ~a'm. For the differential diag-
sinuses of 13 patients. Of the 52 patients, 44
nosis, one should ascertain whether or not the
visited the Department of Oral and Maxil-
maxillary sinus ostium, the nasal cavity or
lofacial Surgery of our hospital because they
any other sinuses are involved with inflam-
had a chief complaint of either pain or dis-
matory disease 13,~4,16). In dentistry, however,
comfort in the upper molar region.
there have been few reports in which the
remaining 8 patients were suspected of hav-
usefulness of CT was evaluated for the diag-
ing odontogenic maxillary sinusitis when
nosis of maxillary sinusitis~%
they first visited the Department of Otor-
we
are
aware
of no
Furthermore,
reports
The
in which
hinolaryngology. All patients had been pre-
ostiomeatal complex such as the maxillary
scribed antibiotics for at least a week prior to
sinus ostium was evaluated by CT.
CT examination. Twelve patients had chief
The purpose of this study was to assess the usefulness of CT imaging for the diagno22 (72)
complaints of oro-antral fistulas caused by extraction of upper molar teeth.
Fig. 1
Three types of maxillary sinusitis. Type I (A), TypeII (B), and TypeIII (C). upeer : level of the sinus floor Iower: level of the zygomatic arch
2. CT examination
CT
All the C T e x a m i n a t i o n s w e r e p e r f o r m e d w i t h a T C T 60A s c a n n e r ( T o s h i b a Medical,
findings
of
the
maxillary
sinus
ostium and p a r a n a s a l sinuses were a n a l y z e d as follows.
T o k y o , J a p a n ) o p e r a t e d at 120 k V p w i t h 200
a)
mAs. B o t h a x i a l a n d c o r o n a l C T scans w e r e
ostium.
p e r f o r m e d for all patients. A x i a l scans w e r e
Evaluation
of
the
maxillary
sinus
W h e t h e r the m a x i l l a r y sinus ostium was
o b t a i n e d p a r a l l e l to the n a s o - m e a t a l line w i t h
opened or o b s t r u c t e d was e v a l u a t e d in all
a slice t h i c k n e s s of 2 m m and at i n t e r v a l s of
p a t i e n t s to d e t e r m i n e w h e t h e r
4 8 mm.
c o m m u n i c a t i o n b e t w e e n the m a x i l l a r y sinus
C o r o n a l s c a n s w e r e o b t a i n e d per-
p e n d i c u l a r l y to n a s o - m e a t a l line with a slice
and the m i d d l e n a s a l meatus.
thickness
CT
through
of 2 m m the
at
anterior
intervals portion
of 4 m m
where
the
findings c o n c e r n i n g the
there
was
F u r t h e r , these ostium
were
c o m p a r e d w i t h those of the inside of the
o s t i o m e a t a l c o m p l e x , including the m a x i l l a r y
m a x i l l a r y sinus.
sinus ostium
into the following t h r e e t y p e s b a s e d on the
were
and
involved,
or
ethmoidal at
infundibulum
intervals
t h r o u g h the p o s t e r i o r portion.
of 8 m m
T h e l a t t e r w e r e classified
e x t e n t of soft tissue m a s s in the m a x i l l a r y sinus (Fig. 1).
3. Analysis of CT findings 23 (73)
T y p e I : M a s s is m o s t l y l i m i t e d to the f l o o r of the m a x i l l a r y sinus. T y p e II : M a s s is s p r e a d over the entire m a x i l l a r y sinus f r o m floor to the
top,
but
an
air
cavity
r e m a i n s in the sinus. T y p e l I I : T h e m a x i l l a r y sinus is a l m o s t c o m p l e t e l y occupied b y mass. b) Comparison
of C T
findings of the
m a x i l l a r y sinus o s t i u m and clinical diagnosis Opening of the ostium could be clinically d i a g n o s e d for 17 cases, including 12 p a t i e n t s
Fig. 2
Left maxillary sinusitis Coronal CT images demonstrated the communication between the maxillary sinus and the middle meatus. It was proved on the coronal image that the maxillary sinus ostium (arrow) was opened though soft tissue mass (ST) in the sinus. * : middle meatus, ..- : ethmoidal isfundibulum M : middle turbinate
Fig. 3
Left maxillary sinusitis The left maxillary sinus is occupied by soft tissue mass and its ostium was considered to be obstructed because soft tissue mass is seen in the region of the ostium and infundibulum. Conversely, the right maxillary sinus ostium (arrow) is proved to be opened on the image. * : middle meatus, ... : infundibulm, M : middle turbinate
with o r o - a n t r a l f i s t u l a and 5 p a t i e n t s who u n d e r w e n t m a r s u p i a l i z a t i o n of the m a x i l l a r y sinus soon a f t e r C T e x a m i n a t i o n . In those cases,the ostium w a s c o n s i d e r e d to be opened if l e a k a g e of i r r i g a t i n g solution w a s o b s e r v e d into the n a s a l c a v i t y when injected into the m a x i l l a r y sinus t h r o u g h the fistula.
The
solution w a s injected with a g r e a t c a r e not to i n c r e a s e the pressure. A l t h o u g h the injection p r e s s u r e 5) w a s not m e a s u r e d , the solution could flow b a c k w a r d to the oral c a v i t y while being injected to the m a x i l l a r y sinus. c ) E v a l u a t i o n of i n f l a m m a t o r y disease in the other p a r a n a s a l sinuses and the n a s a l cavity T h e presence of i n f l a m m a t o r y disease w a s e v a l u a t e d n o t only for the e t h m o i d and sphenoid sinuses, b u t also for the middle and s u p e r i o r m e a t u s of the nose into which those sinuses drain. Results
1.
Evaluation of the maxillary sinus ostium M a x i l l a r y sinus ostium w a s c o n f i r m e d to
be open in 20 of 55 c a s e s on c o r o n a l C T i m a g e s (Fig. 2). In the o t h e r 35 cases, the ostial o b s t r u c t i o n w a s s u s p e c t e d b e c a u s e a soft tissue m a s s occluded the r e g i o n of the ostium a n d e t h m o i d a l infundibulum (Fig. 3). Conversely, it w a s difficult to e v a l u a t e the
24 (74)
Table 2
Relation between CT findings of maxillary sinus and the ostium (Number of Cases) Ostium Maxillary sinus Opened Obstructed Total Type I 15 4 19 Type II TypelII Total
Fig. 4
5 0 20
4 27 35
9 27 55
Table 3
Comparison of CT findings and clinical diagnosis of the maxillary sinus ontium (Number of Cases) CT findings Clinicaldiagnosis Opened Obstructed Total Opened Obstructed Total
3 0 3
9 5 14
12 5 17
Left maxillary sinusitis A, B and C are the coronal images of the same patient serially scanned with a slice interval of 4 mm. The ostium of the left maxillary sinus was considered opened based on clinical findings, but it was considered to be obstructed on the images because toft tissue mass was seen in the region of the ostium, infundibulum and midde meatus. arrow : ostium, * : middle meatus, ... : infundibulum, M : middle turbinate (contralateral side)
ostium on axial C T images and only one case
in which the status of the ostium could be
was
clinically diagnosed.
confirmed to
be
opened
using this
modality. T h e r e l a t i o n b e t w e e n C T findings of the
T h e result is shown in
T a b l e 3. T h e ostial o b s t r u c t i o n was suspected on c o r o n a l C T images in 9 of 12 cases in
m a x i l l a r y sinus and the ostium is shown in
which it was
T a b l e 2. T h e ostium was c o n f i r m e d to be
opened (Fig. 4).
opened on coronal C T images in 79% (15/19) cases, and 0% (0/27) of the TypelII cases.
3. Evaluation of inflammatory disease in the other paranasal sinuses and the nasal cavity
2. Comparison of CT findings and clinical diagnosis of the maxillary sinus ostium
m a x i l l a r y sinus alone in 17 of 55 sinuses. In
C T findings of the ostium were compar-
the other 38 sinuses, the ethmoid a n d / o r
ed with the clinical diagnoses for the 17 cases
sphenoid sinus was involved in addition to the
of the T y p e I cases, 55% (5/9) of the T y p e I I
clinically considered to be
T h e i n f l a m m a t o r y disease involved the
25 (75)
Table 4
Relation of the inflammatory disease of the paranasal sinuses and the nasal meatus Inflammatory disease in the meatus Inflammatory disease in paranasal sinuses Middle meatus Superior meatus + + Anterior Ethmoid Sinus
+ -
38 17
Posterior Ethmoid Sinus
+ -
8 47
Sphenoid Sinus
+
7 48
6 28
1 20
55
34
21
-
Total
34 4 0 17 (x 2 36.1 : p
