Endonasal Operation of Chronic Ethmoiditis:
by
Ryo Takahashi, M.D.
Department of Otorhinolaryngology, Tokyo Jikei University School
of Medicine
In view of the complex topographical relationship of the ethmoid
sinus and to assure complete removal of the diseased tissue, the
combined method seems to be preferred as the operative field can
be viewed from various angles. I feel sure however, that the
basic approach should be intranasal and that when the combined
methods are used, the transmaxillary or extranasal route should
be regarded as an auxiliary procedure to supplement or confirm
the results of the intranasal operation.
In other words, even with the combined method, experience
and proficiency with the intranasal techniques will make
attainment of the objectives of the operation the
easiest.
My preference for the intranasal route as the basic route for
ethmoidectomy is based on the following 3 reasons;
1) It is the most natural approach and the easiest to understand
in terms of orientation.
2) It is the most convenient route for visualizing dangerous
areas.
3) Although it is said that the restricted view through the
nose makes the surgical procedures difficult, I have not
experienced too much trouble in this respect.
Firstly, as the most convenient position of the patient for
intranasal operation is the sitting position which we are most
accustomed to in our daily practice, the intranasal findings as
well as the topography of the internal structures are most easily
understood and the position of the head(line of vision) and hands
of the operator are well coordinated for fingertip control of the
operative manipulations.
As often pointed out by Kubo, when the most frequently used
transmaxillary approach is the combined method is employed, the
anatomical situation of the ethmoid sinus which we normally
picture changes drastically and, unless this difference is fully
recognized, unforeseenable difficulties may arise. Although the
external approach differs from the intranasal route only with
respect to the angle to the sagittal plane, a similar situation
is encountered as the operator stands to the side of the
patient's head.
Secondly, it is imperative that the dangerous areas in ethmoid
sinus operation and procedures that are most likely to cause
trouble are known. As injury of the roof of the ethmoid sinus may
lead to intracranial complications, or to penetration of the
lamina papyracea and intraocular complications, these two regions
are mentioned specifically in all textbooks.
Another region which must be considered is the eminentia optica,
the elevation of the wall of the extreme posterior sinus that
encloses the visual nerve(= optic nerve), as injury to this
structure may result in trauma of the visual nerve.
The most hazardous area is the medial side of the roof of
anterior ethmoid. While this part of the anterior ethmoid sinus
is directly visible through the extranasal route, injury of this
region can be avoided with the intranasal approach with the aid
of preoperative X-ray studies. Of course, this region is not
accessible through the maxillary sinus. An important point is
that the intranasal approach affords a direct view of most of the
roof of the ethmoid sinus, which allows more careful inspection
following procedures on the posterior ethmoid sinus.
To avoid injuring the lamina papyracea, one must obtain a wide
and direct view of this structure which can only be fully exposed
with the intranasal method. The lateral wall of the ethmoid
sinus is difficult to see when the approach is
through the maxillary sinus. A case of blindness due to injury of
the Eminentia optica during a transmaxillary operation of the
ethmoid sinus was described in my first report on the Eminentia
optica.
Lastly, the restricted surgical field which makes operation
difficult, especially in Japanese, is the disadvantage of the
intranasal method that is often expressed. With regard to the
intranasal approach for the operation of the ethmoid sinus, the
general view is that it is suitable in one-third, possible after
reconstructive surgery of the nasal cavity in one-third,
and unsuitable in one-third of all cases.
It has been my experience, though, that even in markedly thin
noses the intranasal approach is possible in a large number after
reconstructive surgery of the nasal cavity, especially
after correction of the deviated septum. Admittedly, intranasal
operation in such cases is difficult and the combined approach
would be better, but a more difficult problem in these patients
is the postoperative treatment. In fact, it is considered that
just as much care and detailed treatment are needed in the
management after ethmoid sinus operation as in the after
treatment of radical middle ear operation.
As reconstruction of the nasal cavity prior to intranasal
operations that might be necessary. This problem could be more
readily understood by considering the typical types of abnormal
intranasal findings shown in Figure 1, A1 and A2.
Morphologically, the abnormal findings present a picture that is
due to altered inter-relationship of the lateral wall (chonchal
walls) and the nasal septum.
When surgery is performed to correct such deformities, it is
obvious that the entire operation is performed to correct such
deformities, it is obvious that the entire operative treatment
should be such that subsequent ethmoid sinus operation and any
other procedures preceding or following ethmoidectomy are
facilitated.
Consequently, the various operations for the intrinsic diseases
of the nose are interrelated by morphological consideration
and therefore the order in which the operations should be
performed is fairly clear.
In other words, a general plan of the order of the surgical
procedures should be made prior to surgical intervention.
For example,
when the nasal disorder is complicated by the various intrinsic
lesions shown in A1 and A2, the morphological
findings can be interrelated in the following
fashion:
frontal sinus ]
maxillary sinus ] ---- ethmoid sinus ---- conchal wall
----nasal septum ---- opposite side
sphenoid sinus ]
[ -------------------------------]
E
F
G
HI
In such structural abnormalities and lesions of the mucous
membrane, surgical treatment of each lesion should be planned as
a part of a whole with respect to the intranasal
structures, irrespective of the lesions of the mucous
membrane.
In this way, when the series of operation is planned so
that each procedure can be most easily performed, the order of
the operation becomes clear.
For example,
in A1 (ethmoiditis chronica and polyp, right: rhinitis
chronica hypertrophia and deviatio septi nasi), surgical
treatment of the various structures should be executed in the
order of F --> G --> H;
in A2 (pansinusitis and polyp, right: hypertrophia septi dexter +
rhinitis chronica hypertrophia sinister + deviatio septi nasi),
the order of EF --> G --> HI.
In the latter case, it is important that during the EF procedures
which consist of intranasal operation of the ethmoid cell and
other sinuses, reconstruction of the conchal wall is
also performed together with ethmoidectomy. That is, the medially
displaced conchal wall should be corrected as shown Figure 1 B.
(In certain cases presenting a hypertrophic inferior concha, this
structure is excised or removed as a part of reconstruction
of the lateral nasal wall).
The way is thereby prepared for completion of next step (G) which
consists of correction of the deviated septum, and the successful
execution of this stage (Fig. 1C) is a necessary condition for
proper execution of operations of the lateral nasal wall and
sinuses of the opposite side (HI).
When there is nodular thickening of nasal septum as in A2 ,
operation of this lesion, as a rule, is performed after
corrective surgery of the septum in view of its interrelationship
with the nasal septal operation, preferably after operation
of structures of the opposite side (HI); that is, at the
last.
It is sometimes performed during surgical procedure of the right
side, but adhesions between the conchal and septal walls easily
occur and operation of the deviated nasal septum is also made
more difficult.
The actual surgical procedures of intranasal ethmoidectomy
will next be described, based on our present method.
Instruments:
The surgical instruments used in this operation have been
described elsewhere and will be mentioned only in certain
procedures when necessary.
Position of Operator and Patient:
The patient is placed in the sitting position, well back in the
chair, with an assistant holding the head with both hands. The
assistant should be trained to move the patient's head in any
direction required by the slightest shift in the operator's head.
The operator is also seated with the nasal floor of the
patient.
Anesthesia:
Topical anesthesia is sufficient. The nasal cavities are
carefully and adequately cocainized, first with a 2 % or 3 %
solution containing 1:1,000 adrenaline and then with a 10 %
solution. Soaking a piece of gauze in the cocaine solution and
inserting it into the nasal cavities will not provide adequate
anesthesia alone. The cocaine solution should be adequately
applied to the anterior wall of sphenoidal sinus and its sides in
the posterior meatus through the olfactory fissure, sometimes
with a 20 % solution. Light general anesthesia with an
intravenous anesthetic is sometimes combined.
X-ray Examination:
A careful study of both the A-P and lateral views in respect to
the topographical relationships and severity of the lesions,
especially the former helps greatly in the planning and execution
of the surgical procedures.
The main topographical features on the antero-posterior view that
should be clarified are;
1. the widths of the anterior and posterior ethmoid cells,
2. the medial cranial wall of the ethmoid sinus,
3. relation of the anterior roof of the ethmoid sinus to the
frontal sinus,
4. degree of inclination of the anterior and posterior cribriform
plate,
5. presence or not of cells in the maxillary sinus,
6. and the transition of the lamina papyracea to the superior
wall of the maxillary sinus and its relation with the upper
margin of the inferior turbinate.
On the lateral view,
1. the relation of the anterior and posterior walls at the
orifice of the frontal sinus,
2. the relation of the cribriform plate to the sphenoidal sinus
should be observed.
Surgical procedures:
description of surgical procedures in 7 successive stages so that
intranasal procedures can be carried our in an orderly
fashion
Stage 1:
Tx. of mainly the lower anterior half of the ethmoid sinus up to
the ground lamella (IIIgl) that borders the anterior and
posterior ethmoid cells, entering from the middle meatus;
Stage 2:
removal of IIIgl and Tx. of the posterior ethmoid cells;
Stage 3:
Tx. of mainly the upper anterior half of ethmoid cells;
Stage 4:
Tx. of the extreme anterior part of the anterior ethmoid cells in
relation to the frontal sinus;
Stage 5:
Tx. of the region of the ethmoid sinus in relation to the
maxillary sinus;
Stage 6:
opening the sphenoid sinus, if necessary;
Stage 7:
reconstructive procedures of the conchal walls.
Stage 1:
The topographical structures treated in stage 1 in the order in
which they are encountered are lower half of the uncinate process
(excluding the apex), lower half of the infundibulum, ethmoidal
bulla and cells.
The initial point of penetration into the ethmoid sinus differs
according to the shape of the anterior portion of the middle
meatus (Fig.3);
1. normal type,
2. processus uncinatus type,
3. bulla ethmoidalis type,
4. middle turbinate cell type,
5. narrow nose type
but the main point is that the site of entrance is lateral to the
middle turbinate (normal type, uncinate process type, bullar
type).
When the middle turbinate is enlarged, a part of it is removed,
or only the outer plate when a conchal cell is
demonstrated.
As conchal cells are derived from the posterior ethmoid sinus,
communication with the posterior ethmoidal cells is found on the
interior side of IIIgl and care is needed as the conchal
walls are very thin and easily damaged.
In thin noses the anterior part of the middle meatus is
especially narrow and insertion of the forceps requires care as
the first stroke may penetrate into the orbit, resulting in
marked hemorrhage of the bulbar conjunctiva and eyelids.
Unless the uncinate process is extremely hard and strongly
adherent along the agger nasi to the anterior edge of the
maxillary foramen, separation first of the uncinate process with
a chisel is not necessary.
Cells of the uncinate process or infundibulum are usually left at
this stage of operation, but it is necessary to explore the upper
anterior cells and to confirm their relationship to the roof of
the sinus by consulting the X-ray films and to remove such cells
when they obstruct the view for the second stage
procedures.
In middle meatuses of the uncinate process type, the middle half
of the process is removed and in those of the bullar type, the
bulla is broken into to enter the bullar cell which extends
directly into the ethmoid sinuses, divided by several irregular
septa.
With removal of these septal walls, IIIgl is reached. when the
lamella is irregular or very thin, it may be ruptured with the
septum and the posterior ethmoid sinus entered without always
confirming its presence. Pronounced pneumatic cells of the
infundibulum sometimes extend above the bulla to and behind the
sinus roof so that the roof is already visualized at this stage,
but no further manipulation of this region is necessary.
When there is poor development of the bullar cell and the fossa
in shallow, IIIgl is situated more forward, indicating that the
superior meatus is advanced anteriorly, that the lower part of
the ethmoid bulla which forms the floor of the anterior ethmoid
sinus is reduced in size, and that the anterior support of the
middle turbinate is narrowed, thus making some adjustment
necessary in reconstruction of the conchal walls.
The ground lamella of the ethmoid bone, according to the
description given by Seydel, are shown in the diagrams. For
convenience, each lamella which curves and recedes posteriorly in
the supero-inferior direction is drawn fairly perpendicular in
the diagrams(Fig.5).
Stage 2:
The procedures during this stage extends to the anterior wall of
the sphenoidal sinus after penetrating IIIgl, but the relative
depth of the operative fields in the first and second stages are
inversely proportional as anterior or posterior displacement of
IIIgl is not uncommon.
Confirmation of the IIIgl is possible by exposing the upper and
lower portions to see whether the bony is attached superiorly to
the roof of the sinus on the sagittal plane and whether it
extends into the middle turbinate medially (only, however, when
conchal cells are absent). exposure of the lateral side which is
attached to the lamina papyracea is not done at this stage.
When IIIgl is posteriorly displaced, its position in relation to
the anterior wall of the sphenoidal sinus is explored by probing
through the olfactory fissure.
The IIIgl can be satisfactorily broken through with the
Grunwald's forceps, but a sharp curet(= curette) can be used when
it is difficult to penetrate the hard bony plate or when a smooth
surface makes this procedures difficult. The IIIgl is broken
through its inferior portion, entering a narrow cavity which
corresponds to the descending crus of the superior meatus.
As the medio-inferior portion of this area (the area from the
posterior end of the superior meatus to the lower part of the
anterior sphenoidal wall) is more sensitive to pain than the
sinus itself and is inadequately cocainized, it is better to
reanesthetize this region at this time.
The supero-posterior wall of the superior meatus is formed by the
lamella of the superior concha (= IVgl) and is thinner than
IIIgl.
Insertion of a probe in this area in a postero-lateral direction
sometimes penetrates fairly deeply into the fossa that is firstly
entered when the ethmoid sinus is approached through the
maxillary sinus. The floor of this cavity, which is a
continuation of IIIgl according to Kuboda, is not explored any
further at this stage of operation.
Removal of the mid-portion and some of the upper portion of the
IIIgl should reveal the bullar cells described by Kuboda but
typical structures are seldom seen and usually several irregular
cells between IIIgl and IVgl come into view. Removal of these
cells exposes the entire surface of IVgl which appears much more
irregular than IIIgl.
Sometimes when IIIgl is broken down, the parallel IVgl is also
removed and the single and large ethmoid cell is entered. Usually
there is no septum bisecting the extreme posterior (ethmoid) cell
horizontally, but sometimes a partition that appears as if it
were a lamella of the supreme nasal concha is seen extending from
the sinus roof to the anterior sphenoidal wall.
The descending crus of IVgl is fixed to the anterior sphenoidal
wall and it is extremely important to expose the lowest part of
the extreme posterior cell this part is the extreme limit of the
exenteration of the ethmoidal cells and is an important landmark
in the 5th and 6th stages of operation.
Immediately below and posterior is located the sphenopalatine
foramen, separated by a bony plate and osseous tissue. To leave
intact the reflected part of IIIgl that forms the conchal part,
besides avoiding injury to the conchal wall, the posterior end of
the middle concha that is attached to the palatine bone must not
be broken down(Fig.4 B). This part is liable to be damaged during
the process of breaking through IIIgl posteriorly when the
process is carried to far medially.
During removal of IIIgl, as an imaginary frontal plane drawn to
the posterior wall of the extreme ethmoid cell is approached,
biting maneuvers in the medial direction at the posterior part of
the middle turbinate is stopped.
The IIIgl is removed on the sagittal plane up to the middle
conchal wall with Grunwald's forceps or punch forceps, but only
the accessible parts are removed and a curette should not be
used.
Thus by breaking down IVgl to just before the lowest part of the
extreme posterior cell and laterally to the lamina papyracea, the
posterior ethmoid sinus is completely exposed and the roof comes
fully into view.
From near the middle of the roof of the posterior ethmoid sinus
posteriorly, corresponding to the course of the posterior
ethmoidal nerve, pain is on rare occasions felt and accompanied
by minute bleeding.
Generally the partitions in the sinus can be distinguished from
the sinus roof and lamina papyracea by sight or touch and so
careful inspection and gentle palpation of the structures are
desirable.
The border of the superior concha and IVgl is just as difficult
to perceive as that of the middle concha and IIIgl.
By advancing along the side of the conchal wall and breaking down
the lateral bony plate, a relative thick portion attached to the
anterior sphenoidal wall (orbitopalatine process) is reached,
which is relatively sensitive to pain.
The lateral wall of the uppermost part of the nasopharynx lies
medially to this region, and as the head of the patient is tilted
backwards, the natural orifice of the sphenoid sinus can
often be probed.
A long speculum is used here to provide an adequate view for
complete cleansing of this part. At this stage of the
operation the orbital plate of the ethmoid bone can be clearly
visualized and the degree of inclination of the lamina papyracea
is determined by inspection and consultation of the X-ray
films.
The development of a sphenoethmoidal cell which invariably
overlaps, the sphenoid sinus is revealed when the thin IVgl is
broken through and a very large cavity is immediately
entered.
At times, the sphenoidal sinus is immediately visible as a
rounded eminence. Generally no partitions are found in these
cells. They are sometimes mistaken for the sphenoidal sinus when
large as the sphenoidal sinus is displaced inferiorly and
medially, but they can be differentiated by their communications
with the posterior ethmoid sinus or lack of communication with
the shenoidal sinus.
The appearance of the Eminentia optica in the posterosuperior
corner of a very large sphenoidal cell (= Onodi cell) is an
occasional finding which will be described later.
The posterior ethmoid sinus adjacent to the base of the skull at
the anterior shenoidal wall may extend to or across the midline
to the opposite side. In such instances, it is difficult, if not
impossible, to remove all of the mucous membrane of the cells
with any combination of approaches as when pneumatization extends
into the lesser or greater shenoidal wings. But it should be
remembered here that complete eradication of the mucosa alone
does not always assure cure of the disease.
Stage 3.
The next procedure consists of exenteration of the anterior
ethmoidal cells from back forward. Keeping in mind the spatial
relationship of the various cells generally visualized during the
initial stage of the operation, the area of the lamina papyracea
is first cleaned.
Attention must be given here to the degree of inclination of the
lamina papyracea, which becomes almost perpendicular anteriorly
and also thinner.
However, when there is good development of the frontal
infundibular and bullar cells and strong pneumatization of the
supraorbital wall, the anterior part of the lamina papyracea
describes a half of circle together with the superior wall of the
frontal sinus.
Anterior to the lamina papyracea at the region of the lacrimal
bone which corresponds roughly to the lateral wall of the
infundibulum, the wall is thinnest and easily injured, resulting
in protrusion of the infraorbital fat tissue, so care is needed.
When the protruding fat tissue is mistaken for mucous membrane
and pulled, it will keep coming out as a billowing mass and can
be easily recognized, or a piece squeezed between the fingers
will easily show that the tissue is fat. Protrusion of the
infraorbital fat tissue makes subsequent procedures and after
treatment troublesome but otherwise no serious complication
arise.
As a rule the surface of the lamina papyracea is completely
exposed, but treatment of the lower portion is felt until stage 5
as this part is difficult to visualize clearly with the
intranasal approach.
The procedures anterior to the lamina papyracea include cleaning
of the infundibular region, removal of the uncinate process and
removal of the agger (nasi) cells.
Removal of the uncinate process is an important but difficult
when the process is low.
For removal of the process, an upward angled forceps or punch
forceps is applied from below upward or from back forward without
applying any lateral force. An agger nasi cell or Spatium
subfrontale is easily overlooked.
One method after removal of the uncinate process is to remove the
bulge of the agger nasi and to remove it with strong
forceps.
Let us review the topographical relationships of the cells in
this region.
The lamina papyracea forms the lateral walls of the air cells,
bulla and infundibulum and many air cells open or come into
relation with these structures. especially the superior walls of
many of the air cells that come into relation with the
infundibulum or bullar cell fossa form the roof of the ethmoid
sinus. The lacrimal bone lies lateral to the uncinate process and
the junction of the uncinate process and the agger nasi lies on
the frontal plane formed by the naso-lacrimal groove and the
suture between the lacrimal bone and the frontomaxillary
process.
Therefore, treatment of the posterolateral part of the agger nasi
from the anterior junction of the uncinate process laterally is
dangerous unless the process is continued from the posterior part
of the lamina papyracea. The part of the ethmoid sinus lateral to
the anterosuperior attachment of the uncinate process (which
corresponds to the anterosuperior extremity of the middle meatus,
lateral to the attachment of the middle concha) is the narrowest
portion of the sinus and thin-walled, but access to this area
through the nose is difficult, which affords some protection
(Fig.14).
The part where the suture between the uncinate process and agger
nasi begins to separate is about on the same level as the
inferior margin of the middle turbinate and from this level the
lateral wall of the ethmoid sinus curves abruptly
lateroinferiorly and fuses with the superior wall of the
maxillary sinus.
Treatment of the sinus roof has been reported elsewhere and will
not be described in detail, but the most important consideration
in the procedures in this region must be given to the
topographical relationships of the ethmocranial medial wall,
which is closely and irrevocably related to the inclination and
height of the sinus roof and to the anterior ethmoidal
nerve.
Treatment of the sinus roof is started from the lateral side,
continuing anteriorly from the 2nd stage. The lateral wall of the
sinus roof is thick.
Anteriorly, the roof inclines from the laterosuperior portion
medially and at the region of transition of the ethmoid sinus to
the frontal sinus where the roof curves anterosuperiorly is
attached the IIIgl.
The anterior ethmoidal nerve is usually found coursing just
anterior to the attachment of the IIIgl ( The anterior ethmoidal
nerve together with the artery of the same passes through the
Canalis orbitocranialis which is tubular or semitubular bony
canal in the anterior ethmoid sinus roof).
When the roof is low, the anterior surface of the posterior sinus
is generally smooth, but when exceptionally high, the Canalis
orbitocranialis frequently passes through IIIgl or IIgl and
removal of these structures is sometimes required to make the
surface of the bony roof smooth. This is especially so when
orbital cells penetrate deeply into the superior orbital wall,
posterior to these lamellae. In these instance it is necessary to
desensitize the anterior ethmoidal nerve. Anterior to these bony
plate are found cells of the bullar fossa, bullar cells,
infundibular cells or the frontal sinus, which can generally be
seen clearly.
When the anterior ethmoidal nerve is touched, pain will be felt
associated with slight bleeding, which serves as a sign that the
wall separating the base of the skull and sinus has been
reached.
After confirmation of this sign, the nerve is anesthetized and
bleeding stopped.
Manipulation in the middle conchal region at this stage of
operation is at the superior lateral surface of the anterior
conchal wall corresponding to the upper attachment of IIgl at the
upper part of the uncinate process.
The curette or forceps is reversed and advanced superiorly to the
dangerous area of the sinus roof. Indiscriminating curettage of
this area must be avoided at all cost.
First the area around the dangerous region is exposed and then
advancing slowly from exposed to unexposed areas, the entire
region is cleaned.
The lateral wall of the anterior ethmoid sinus describes an
outward curve, and the beginning of the superolateral curvature
is at the suture between the frontal bone and lamina papyracea,
which can be roughly placed on the horizontal plane passing
though the point of the maximum depression of the nasal root
(Fig.16).
However, the curvature of the lateral wall just above the suture
is at first gradual and then bends acutely (which differs from
the curvature of the lateral wall of the posterior ethmoid
sinus). This curved position of the lateral wall of the frontal
sinus and the lateral walls (actually the later-inferior wall) of
the infundibular cells and bullar cells ( and extensions of
orbital cells).
At the end of the 3rd stage of the operation, the middle concha
is usually freely movable except when the bone is thick.
Stage 4:
Following exenteration of the anterior ethmoidal cells, the
antero-superior portion in relation to the frontal sinus region
is next treated.
It is necessary here to reexamine closely the preoperative X-ray
films in the light of the operative findings up to this stage in
order to gain a clearer picture of the topography of the frontal
sinus and the various parts of the ethmoid sinus in relation to
the frontal sinus.
The most important relationship here is that between the frontal
sinus and the infundibulum. The infundibulum ends
anterosuperiorly in one of three ways. It opens directly into the
frontal sinus which is the typical situation, ends posteriorly to
the frontal sinus. The cells that open into the infundibulum also
show similar relationships. Bullar cells may extend and develop
largely posterior to the frontal sinus appearing as orbital
cells, or cells of the uncinate process or from the frontal
sinus, the Spatium subfrontale, situated anteromedially to the
frontal sinus may further complicate the relationship of the
communication with the ethmoid sinus.
Whichever the case may be, it is essential that the intervening
walls between the ethmoid and the frontal sinus are broken down,
taking care not to injure the walls of the adjacent organ and by
exenteration of the anterosuperior part of the ethmoid sinus
along the infundibulum in a superior ( as the head of the patient
is tilted back) and slightly lateral direction, communication
with the frontal sinus is made. The lateral wall at this portion
curves outward superiorly and the roof curves upward anteriorly,
and it is necessary that this area is made as smooth as possible,
using mainly a punch forceps.
When the patient's head is tilted well backward, the bordering
wall of the frontal sinus is fairly well visualized unless
obstructed by the agger nasi or anterosuperior extremity of the
middle meatus.
Even with fairly wide visualization of the operative field, it is
impossible to see the area from the posterior surface of the
frontomaxillary process to the frontal sinus (anterior
surface).
For treatment of this area, after adequate exploration and
consultation of the X-ray films, the forceps is advanced in the
manner of a probe in the anterosuperior (posterior surface of the
medioinferior process of the superior orbital edge) direction and
any free edges of the lamellae are removed. The point of the
forceps should never be placed on the medial wall. In this way
adequate communication with the frontal sinus is provided without
the necessity of using a chisel, file or curette.
On the contrary, when these instruments are used, there is liable
to be excessive granulation (tissue) postoperatively with
subsequent occlusion of the communicating route.
Suppurative frontal sinusitis is often curable just by the
creation of an communicating route with the removal of the
intervening wall and eradication of the sinus mucosa, and I have
even experienced two cases of pyoceles of the frontal sinus that
ere successively cured with this method.
However, as the size of the created communication between the two
sinuses will depend on the size of the gap between the
surrounding walls, which is subjected to anatomical
reconstructions, a combined approach with an external opening
will become necessary when communicating passageway is very
narrow.
Stage 5.
The main procedures here consist of cleaning of the ethmoid sinus
floor and communicating with the maxillary sinus.
Compared with the posterior sinus, the anterior sinus is
narrower, the lateral wall higher and less slanted.
The part where the lateral and inferior walls of the ethmoid
sinus fuse with the superior wall of the maxillary sinus
corresponds to the lateral inferior part of the bulla or IIgl and
posteriorly the lateral part of the descending crus of
IIIgl.
The part of confluence of IIgl with IIIgl posteriorly mainly
forms the floor of the posterior ethmoid sinus, which is
depressed in the form of the bottom of the ship and devided
medially and laterally by the upper margin of the sinus
orifice.
The upper portion forms a triangle, bounded by the
maxillo-orbital wall laterally and posteriorly and by the upper
ridge of the ostium. The lateral half of this portion (Fig.20 A)
corresponds to the bony plate through which the ethmoid sinus is
entered from the maxillary sinus.
Before this part of the ethmoid sinus floor is cleaned and
portion A is removed, guided by the previously exposed uncinate
process in the anterior ethmoid sinus, the soft parts of the
ostium are removed with a curved curette and backward and upward
forceps.
Difficulties are encountered in removing the lateral part of the
portion A when the maxillary sinus is well developed, but
rotation of the head the patient laterally provides a somewhat
clearer view.
It is necessary to use a stiff curette or strong forceps here
because of the relative thickness of the bony wall. With removal
of this part of the floor of the posterior ethmoid sinus, the
posterior end of the descending crus of IIIgl which is situated
above and slightly medially is disclosed and the anterior
sphenoidal wall is reached, but this region is left untouched
until the next stage.
It is important, though, that the attachment of the posterior end
of IIIgl to the palatine bone is not separated.
To assure that the attachment is left intact, it is first
necessary to visualize the posterior bony border of the ostium
and one must refrain from the use of the biting forceps in the
posteromedial direction when this structure is approached
during removal of IIIgl posteriorly.
Separation of the posterior attachment of the middle concha will
tend to leave a dangling and unstable middle concha, especially
when the superior meatus penetrates deeply within the conchal
walls (Fig.21 A).
Manipulation in the region of the ostium become more difficult
anteriorly because of the presence of the agger nasi and
inferior turbinate and as the attachment of the upper border of
the ostium runs from posterolaterally, and so this region is best
treated in continuity anteriorly from the confluence of the
lamina papyracea with the superior wall of the maxillary sinus.
The deep penetration of Haller's cells along the superior wall of
the maxillary sinus also makes it difficult to completely clean
this area intranasally unless the cell structure is large and
simple.
Around the uncinate process (mainly laterally) which forms the
extreme anterior part of the sinus are found cells of the
uncinate process, lacrimal bone and agger nasi, and it is
essential that the region around the uncinate process to the
agger nasi anteriorly and the to the lacrimal bone laterally is
cleaned, for which good knowledge of the topography of this
region is essential.
An acutely curved curette, a curved punch forceps and a backward
forceps are used to remove the apex of the uncinate process, and
the ostium is also cleaned of any remnants of soft tissue.
At the posterior margin of the ostium corresponding to the medial
wall of the posterior part of the maxillary sinus is found a
crescent-shaped bony plate which is relatively thin except for
the base (Fig.23, H). This bony plate is mostly removed to
provide adequate opening of the ostium, but the posterosuperior
corner near the sphenopalatine foramen must not be removed. as
exenteration of this part which is formed by the palatine bone
and ethmoid bone of the inferior concha is often quite painful,
injection of an anesthetic solution is desirable ( The subsequent
use of the transmaxillary approach is facilitated by prior
application of 10 % cocaine with a strongly curved applicator and
injection of several milliliters of the solution trough the
opened ostium).
Stage 6:
The procedures here is a continuation of the preceding procedure
and consists of treatment in the area of the sphenoid sinus. The
relationship that requires care in this stage of the operation is
that of the apposing walls of the sphenoidal posterior ethmoid
sinuses.
When sphenoidal cells are present, the sphenoidal sinus is
displaced inferiorly or medioinferiorly and the two sinuses face
each other on a horizontal plane.
When no sphenoidal cell is present, the relationship differs
according to the relative width of the sinuses, the manner of
transition of the lamina papyracea to the lateral wall of the
sphenoid sinus, and the relation between the conchal wall and the
anterior wall of the sphenoid sinus, resulting in various ways in
which the ethmoidal sinus and sphenoidal sinus are founded to be
adjoined at operation (Fig.24 A,B,C).
The ease or difficulty in creating a communication between the
sinuses will therefore depend upon this relationship. In general,
the larger the shenoidal sinus or the wider the posterior ethmoid
sinus, the larger is the area of contact of the two sinuses
(width between a and b in the figure) and the easier it is to
create an opening between the two. In the case of A in Fig.24,
the posterior extremity of the conchal wall (supreme concha) is
partially removed (Fig.25 A), or the sphenoidal opening in the
common nasal passage is enlarged (Fig.25 B).
The thickness of each lamella forming the bony plate between a
and b in Fig.24 when both sinuses are well developed in almost
the same or thinner.
The first step consists of cleansing and smoothening the area of
the anterior sphenoidal wall from the roof of the posterior
ethmoid sinus and laterally from the lamina papyracea. as both
the sinus roof and the lamina papyracea become thicker
posteriorly and can be clearly seen, no danger is involved when
the procedure is carefully done. Medially, the anterior
sphenoidal wall is removed up to a line drawn perpendicularly to
the ostium. A good view is obtained with a long speculum for the
procedure.
Next, the lower part of the region between a and b is
cleaned. This procedure requires the greatest care. Using a punch
forceps, the intervening wall is removed from the lateral part.
Even when the lower part of the sphenoidal sinus is deeply
recessed (b), the wall rises anteriorly and becomes shallow and
as smooth as part (a).
The eminence formed by the wall between part (a) and the
previously exposed floor of the extreme posterior ethmoid cell is
removed and lowered as much as possible. At this part, when the
extreme posterior cell is large, the upper half of the wall of
the sphenopalatine foramen is liable to be formed by the floor of
the cell and part (a), whereas when the cell is not large the
same wall is more apt to be formed by the posterior meatus and
part (a) (Fig.26 A & B).
After leveling this part between the sinuses, lateral to this
leveled area attaches to the lamina papyracea might be found
remaining parts of a bony plate, the IVgl, and, still posteriorly
and laterally, attached remnants of the descending crus of IIIgl.
From this posterior part of the superior meatus, extension of the
maxillary cells along the floor of the orbit is sometimes found
and the floor of the superior meatus is greatly widened, making
it difficult to remove all the lateral part of the descending
crus of IIIgl intranasally. Also, the medial part is removed,
care must be taken to avoid breaking the attachment of the
posterior end of the middle concha and the palatine bone. One
rather tends to place the spatial relationship of the palatine
bone in a medial position, but it is necessary to know that the
frontal section of the palatine bone is situated on a sagittal
plane running about near the center of the posterior ethmoid
sinus (at about the middle level) (Fig.28.).
Simple opening of well developed ethmoid sinus cells or the
shenoidal sinus is fairly easy because of the simple structure of
the air cells, although there may be irregularity and unevenness
of the walls. However, injury of the walls may lead to disastrous
consequences. As most of the walls of these sinuses are adjacent
to the cranial fossa, damage to any of the walls, of course, is
dangerous, but there is a part of the walls that is more liable
to be damaged that other parts. This structure which is not
always present depends on the degree of pneumatization in
relation to the optic canal and appears as an elevation on the
sinus wall where the superior, posterior and lateral walls
meet.
Through the intranasal route, this structure is located directly
in the line of approach of the second and first stages of the
operation and the wall of the protuberance is thinner than that
of the other parts.
Therefore, any blind or sudden thrust of instruments into this
region is likely to damage the wall of the canal, and I have
personally encountered several cases of visual impairment
presumably due to such inadvertent procedures, which were
confirmed at reoperation. But such injuries will rarely occur
when the operation is performed as described and the radiograms
are carefully consulted.
Stage 7:
The final stage of the operation consists of correction of any
displacement of the middle turbinate such as when there is
deflection of the nasal septum and the middle conchal wall is
deviated medially on the concave surface of the septum or
laterally on the convex side of the septal deviation.
The deviated conchal wall is forcibly restored to the sagittal
plane gradually by inserting an elevator into the upper part of
the olfactory fissure (Fig.31 A) or into the opened ethmoid
cavity (Fig.31 B) and by gradually exerting pressure outwardly or
inwardly. Of course, this procedure is often unnecessary when the
conchal wall is pressed laterally against the nasal wall (B) as
the conchal wall will become perpendicular or even curve in the
opposite direction after the ethmoidal procedures.
Slight deviations of the conchal wall can be easily corrected
simply by inserting packs into the opened ethmoid cavity and
olfactory fissure, but complete or partial infracture of the
turbinate is required when the deviation is severe or the wall is
thick.
As long as undue force is not exerted, there is no danger of
damaging the cribriform plate, even though the upper edge of the
elevator is pressed against the cribriform plate, but it is
better not to have the elevator touching this structure.
At times the concave side of the middle turbinate faces outward
and repositioning of this structure will result in occlusion of
the middle meatus. This can be avoided by lifting the fractured
turbinate and repositioning it in the sagittal plane as narrowing
of the middle meatus, especially of the anterior part, (anterior
portion of middle concha) may occur, due to proliferation of
granulation in the anterosuperior part of the meatus and
subsequent cicatrization and contracture.
It is therefore necessary that the conchal wall is not placed in
a position lateral to the sagittal plane and proper
aftertreatment is instituted. A piece of Rivanol gauze, about 2,5
cm x 10 cm, is then inserted loosely into the ethmoid cavity,
into the olfactory fissure. The lower common nasal fossa is
packed as usual.
This completes the operation.
In conclusion, for the surgery of the ethmoid sinus, it is
essential that the anatomical relationships of the structures are
fully understood. In particular, rather than the internal
structure of the ethmoid sinus itself, knowledge of the walls
bordering the ethmoid sinus and surrounding organs and structures
is more important. In fact, through exposures of the bordering
walls of the ethmoid sinus is by itself a sign of the
completeness of the operation and, in addition, helps prevent
serious complications. Moreover, the intranasal approach, whether
alone or in combination with other routes, might be considered
the most natural and basic method for the operation of the
ethmoid sinus.
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Originally published in; The surgery Vol. 4 1: 1950.
1.