malposition of parts is a pendent epiglottis--_i.e._ an epiglottis
which by being bent too far over covers the laryngeal opening and
prevents a view. This obstacle exists to a certain extent in most cases
that come under observation, but is easily overcome by letting the
patient sound the vowel sound of _eh_, which causes a rising of the
epiglottis and opens the laryngeal cavity to view. There are some
cases, however, in which this expedient does not sufficiently raise the
epiglottis to obtain a glimpse of the vocal cords, and only the
arytenoid cartilages are seen, from the motion and color of which we
can often obtain valuable information in regard to pathological
processes. In these cases, when it becomes absolutely necessary to see
the whole extent of the vocal cords, we may succeed by causing the
patient to laugh in a high key, but when this fails the only resource
left is to lift the epiglottis by grasping its upper margin with a pair
of curved forceps especially designed for this purpose and called
epiglottis forceps (Fig. 6). If this instrument is not at hand, the
same object may be attained by clasping the edge of the epiglottis with
a bull-nose forceps, to which is fastened a string weighted at the
other end by a small weight, such as a rifle-bullet. The string with
its weight hanging out of the mouth of the patient makes traction upon
the forceps, and thus the epiglottis is raised. In cases of operation
within the laryngeal cavity this method of raising the epiglottis is
even preferable to the epiglottis forceps, because it leaves the hands
of the operator free to use the mirror and the instrument to be used in
operating.
[Illustration: FIG. 6. Elsberg's Sponge-holder and Epiglottis Forceps.]
AUTO-LARYNGOSCOPY.--There is perhaps no better method for the beginner
to overcome the difficulties besetting laryngoscopy than to practise
the art on himself, for then only will he be able to appreciate to its
full extent the necessity of observing all the minute details described
above, as the pain and inconvenience which he inflicts upon himself by
his false movements will teach him better, and enable him to attain
proficiency in the use of his instruments quicker than any other method
of practice. Nothing need, for auto-laryngoscopy, be added to the stock
of instruments necessary for the examination of others, except a stand
to which the reflector is fastened and a small toilet-mirror. The
observer seats himself beside a table upon which, at his left, is
placed the lamp a little behind his head and the centre of the flame on
a level with his eyes. The stand, an ordinary retort-stand, is placed
in front of him, and to it is fastened at the proper height the
reflector. On the same stand, and immediately above the reflector, is
attached the plane mirror in such a manner that it can be inclined at
an angle. Inclining the head slightly backward, the observer then by
watching his face in the plane mirror directs the light upon his mouth
by moving the reflector upon its ball-and-socket joint until the circle
falls upon his mouth. He then opens his mouth as wide as possible,
grasps his protruded tongue between the folds of a towel or {30} napkin
held between the thumb and fore finger of the left hand, and introduces
the laryngeal mirror with the right hand in the manner described above.
The laryngeal image as it appears on the surface of the laryngeal
mirror is reflected by the toilet-glass above the reflector, and can be
seen in all its details by the person practising auto-laryngoscopy. By
substituting a perforated mirror for the toilet-glass the student can
demonstrate the image to others in his own person if the observers look
through the perforation in the mirror.
Before giving a description of the laryngeal image it will be well, for
the sake of completeness, to mention the fact that of late photography
has been employed to reproduce this image, both in this country by T.
R. French of Brooklyn[17] and by Lennox Browne of London, England, with
very gratifying results. The writer himself several years ago made
experiments in this direction, which, however, were not very
satisfactory in their results. The method employed by French is a very
simple one, and it will be best to give his own description of the
process:
"The camera consists of a box 4½ inches long, 1-7/8 inches wide, and ¾
of an inch in thickness. The back opens upon hinges, and admits of the
introduction of either the ground glass or the plate-holder. On the
anterior face a tube 1-1/8 inches long is attached, in the outer end of
which the lens is placed. This lens has a focus of 1¼ inches. At the
side of the tube a part of the handle of a throat mirror is fixed, and
into that the shank of the throat mirror is passed and fastened by a
thumb-screw. The shank of the mirror is somewhat curved, and is
attached to the side of the frame holding the mirror. The object of
this is to allow the lens being held opposite any part of the opening
of the mouth, and also to prevent the possibility of a shadow being
cast upon the mirror. In the front part of the box is a shutter made of
lead and perforated with a hole just the size of the lens. The shutter
is held in position by a lever acting as a key on the anterior face of
the camera.
"The apparatus is used in the following manner: A reflector, either
plane or concave, attached to a head band, is arranged over the left
eye so that the pencil of sunlight from the solar condenser is received
upon it and thrown into the mouth. The patient, with the head inclined
slightly backward, now protrudes the tongue and holds it well out
between the fore finger and thumb of the right hand. The throat mirror
with the camera attached, held in the right hand of the observer, is
placed in position in the fauces, and the light adjusted so that the
larynx can be seen with the observer's left eye to be well illuminated.
If, now, the tongue does not mount above the level of the lower edge of
the lens and the lower edge of the mirror, it may be taken for granted
that when the plate is exposed the picture received upon it will be
nearly the same as that seen with the left eye in the throat mirror.
The photograph is taken by pressing upon the key with the index finger;
this releases the shutter, which in falling makes an instantaneous
exposure amounting to perhaps one-seventh of a second.
"In using condensed sunlight with a small camera it is important to
throw the circle of light from the inner side of the reflector, that
nearest the nose; for in this way a part of the larynx exposed to the
lens of the camera may be illuminated which cannot be seen with the
eye. To ensure this it is best to cover the outer half of the reflector
with black silk. On account of the parallax or displacement of the
image due to the difference in point of view between the eye and the
camera, some skill is necessary in managing the illumination so that
the part which it is desired to bring out will be exposed to the lens
if not to the eye."
[Footnote 17: _Archives of Laryngology_, vol. iv. No. 4.]
THE LARYNGEAL IMAGE.--When the mirror is introduced and is held in the
proper place, and the light is reflected downward, the laryngeal image
{31} will appear on the surface of the mirror. As it is, however, so
different from what might be expected after having examined a larynx
removed from the body, it requires a detailed description, and the
student will do well to refer to the diagrams frequently while
examining patients, to make himself familiar with the details he sees,
and to recognize them when they are altered by disease or when they are
slightly different in shape in different individuals. Figs. 7 and 8
represent the image of the larynx in the act of respiration and of
phonation as it appears on the surface of the mirror, while Figs. 9 and
10 are diagrammatic, and are intended to represent the same.
[Illustration: FIG. 7. Laryngeal Image during Respiration.]
[Illustration: FIG. 8. Laryngeal Image during Phonation.]
[Illustration: FIG. 9. Laryngoscopic Diagram showing the vocal cords
widely drawn apart, and the position of the various parts above and
below the glottis during quiet breathing. _g. e._ Glosso-epiglottic
fold. _s. u._ Upper surface of epiglottis. _l._ Lip or arch of
epiglottis. _c._ Protuberance of epiglottis. _v._ Ventricle of the
larynx. _a. e._ Ary-epiglottic fold. _c. W._ Cartilage of Wrisberg.
_c. S._ Cartilage of Santorini. _com._ Arytenoid commissure. _v. c._
Vocal cord. _v. b._ Ventricular band. _p. v._ Processus vocalis.
_c. r._ Cricoid cartilage. _t._ Rings of trachea. (From Mackenzie.)]
[Illustration: FIG. 10. Laryngoscopic Diagram showing the approximation
of the vocal cords and arytenoid cartilages, and the position of the
various parts during vocalization. _f. i._ Fossa innominata. _h. f._
Hyoid fossa. _c. h._ Cornu of hyoid bone. _c. W._ Cartilage of
Wrisberg. _c. S._ Cartilage of Santorini. _a._ Arytenoid cartilages.
_com._ Arytenoid commissure. _p. v._ Processus vocalis and cartilages
of Seiler. (From Mackenzie.)]
The first detail to attract the eye is the epiglottis, which appears as
a yellowish-red arch reaching from side to side across the image. It is
thicker in the middle than at either end, and a protuberance is usually
seen in the centre pointing forward. This arch is the upper margin of
the epiglottis, and the protuberance is the tubercle, situated near the
insertion of the epiglottis into the thyroid cartilage. The shape as
well as the color of the epiglottis is very variable in different
individuals, being sometimes rounded as in the drawings, sometimes
rolled up like a dried leaf, sometimes notched in the centre, and
sometimes presenting a point at this place. However, all these
variations in shape have nothing to do with any pathological process,
and may therefore be termed normal. The color of the organ also varies
from a bluish-yellow to a pink-red, and these variations are also
normal, being due to a greater or less thickness of the tissue covering
the cartilage, which by shining through imparts its bluish color to the
tissue. The superficial blood-vessels also are more prominent in some
individuals than in others, and may not be noticeable in some cases.
{32} Immediately behind the epiglottis we see two pit-like depressions,
separated from each other in the middle by a fold of mucous membrane
and bounded on either side by similar folds less prominent. These folds
are the glosso-epiglottic ligaments, and serve to connect the tongue
with the epiglottis, while the depressions are the glosso-epiglottic
grooves, in which we usually find the foreign bodies which have
accidentally been swallowed.
The ends of the epiglottic arch are lost in folds of mucous membrane,
which run forward and inward to meet in the median line some distance
in front of the epiglottis. Along their course several nodules of
different size are noticed, which are symmetrically situated on either
side. The one nearest to the epiglottis is the cartilage of Wrisberg, a
small cartilaginous nodule imbedded in the tissue. The larger one,
situated at the end of the fold of mucous membrane, is the arytenoid
cartilage, and a third small nodule is noticed close to the arytenoid
cartilage between it and the cartilage of Wrisberg, which is called the
capitulum Santorini. The folds of mucous membrane are termed the
aryteno-epiglottidean or ary-epiglottic folds. Their color is normally
of a pinkish-red, and does not vary much in different individuals.
The arytenoid cartilages forming the ends of the ary-epiglottic folds
are movable, approaching and separating alternately during the act of
respiration, while during phonation they are pressed against each
other, thus obliterating the space between them which is seen when they
are separated. This space is the inter-arytenoid space or commissure,
and is formed by the lateral walls of the arytenoid cartilages and the
upper margin of the posterior portion of the cricoid cartilage. The
mucous membrane in this commissure is very loosely attached to the
deeper structures, and is thrown into folds by the approximation of the
arytenoid cartilages. Its color is much lighter than that of the
ary-epiglottic folds, due to the shining through of the cricoid
cartilage. Outside of the ary-epiglottic folds and the inter-arytenoid
commissure is the tissue forming the posterior and lateral walls of the
oesophagus (not shown in the diagrams), and near the epiglottis a space
called the pyriform sinus is noticed between the ary-epiglottic folds
and the wall of the oesophagus.
Running from the epiglottis to the ary-epiglottic folds are two broad
bands, one on either side, covered with mucous membrane and of a
pinkish-red color, which are lost on either side in the tissue forming
the walls of the laryngeal cavity, while toward the middle of the image
they present concave and tolerably sharp edges. These are the
ventricular bands, which were formerly termed the false vocal cords,
and which form the lip to the opening of the ventricle of the larynx.
Between the ventricular bands filling up the central portion of the
image are seen the vocal cords, two bands of a pearl-white color which
are attached to a cartilaginous process of the arytenoid cartilages,
and run from these parallel with each other to the angle of the thyroid
cartilage immediately below the tubercle of the epiglottis. These
present sharp edges toward each other, and follow the motions of the
arytenoid cartilages to which they are attached, so that when in
inspiration the cartilages are separated the edges of the vocal cords
are also some distance apart, forming, together with the
inter-arytenoid commissure, a triangular opening called the glottis.
That portion of the opening which is bounded on either side by the
edges of the vocal cords alone is called the membranous portion, while
the base of the triangle is termed the cartilaginous portion, being
bounded on either side by the vocal processes of the arytenoid
cartilages. This portion is readily distinguished from the membranous
portion by its slightly yellow color, and by the fact that a very
obtuse angle is formed at the junction of the two portions when the
glottis is wide open during respiration. Through the open glottis the
lower edge of the cricoid cartilage and several of the rings of the
trachea can usually be seen, and there are a few cases in which even
the bifurcation of the trachea can be dimly illuminated, showing in the
{33} laryngeal image the openings of the bronchi. The distance is,
however, too great for bright illumination, and nothing can be seen
distinctly, so that it is of little value in a diagnostic point of
view. During phonation the glottis is narrowed to a slit by the
approximation of the arytenoid cartilages and inner edges of the vocal
cords, and, as has already been stated, the inter-arytenoid space
becomes obliterated. In the higher notes of the female voice, the
so-called head tones, the cartilaginous portion of the glottis remains
closed entirely, while the membranous portion appears as an elliptical
opening which is diminished in its longitudinal diameter with each rise
in pitch. This becomes possible because of the presence in the vocal
cords of a slender rod-like cartilage attached to the end of the vocal
process, which can readily be seen in the female larynx, but which is
only rudimentary in the male.
This description, intentionally, has been made without reference to the
anatomical relation of the parts, but to give a clear idea of what is
seen in the laryngeal mirror. The reader should therefore always bear
in mind that the laryngeal image, being a reflected one, is reversed,
and that, on account of giving a bird's-eye view of the larynx from a
point above and behind the organ, distances are materially diminished;
and the image is also reversed in an antero-posterior direction, so
that the epiglottis appears to be posterior when in reality it is
anterior.
RHINOSCOPY.--Rhinoscopy, or the art of inspecting the nasal cavities
and the naso-pharyngeal space, is divided into two portions--viz.
anterior and posterior rhinoscopy; and it will be convenient to observe
this division in the following description of the methods employed. But
before proceeding with the description it will be well to briefly
review the topographic anatomy of the parts, because in most works on
general anatomy the nasal and naso-pharyngeal cavities are discussed in
a few sentences, and they are rarely if ever examined in the
dissecting-room, so that the student has but a very imperfect knowledge
of the relation of the parts belonging to these cavities. (See Fig.
11.) The nasal cavities, which are wedge-shaped, with a narrow arched
roof, extend from the nostrils to the upper portion of the vault of the
pharynx. Their outer walls are formed by the nasal process of the
superior maxillary and lachrymal bones in front; in the middle, by the
ethmoid and inner surface of the superior maxillary bones; behind, by
the vertical plate of the palate bone and the internal pterygoid
process of the sphenoid and the turbinated bones. These latter run
before backward, three on each side, and are designated as the
inferior, middle, and superior, the latter being the smallest of the
three. The sinuses or spaces between these turbinated bones are called
meatuses; so that the space between the floor of the nose and the lower
turbinated bone is called the inferior meatus, the one between the
lower and middle turbinated bones is the middle meatus, and the one
between the middle and superior turbinated bones is the superior
meatus.
[Illustration: FIG. 11. VERTICAL SECTION OF HEAD, SLIGHTLY
DIAGRAMMATIC. 1. Superior turbinated bone. 2. Middle turbinated bone.
3. Lower turbinated bone. 4. Floor of nasal cavity. 5. Vestibule. 6.
Section of hyoid bone. 7. Ventricular band. 8. Vocal cord. 9 and 23.
Section of thyroid cartilage. 10 and 24. Section of cricoid cartilage.
11. Section of first tracheal ring. 12. Frontal sinus. 13. Sphenoidal
cells. 14. Pharyngeal opening of Eustachian tube. 15. Rosenmüller's
groove. 16. Velum palati. 17. Tonsil. 18. Epiglottis. 19. Adipose
tissue behind tongue. 20. Arytenoid cartilage. 21. Tubercle of
epiglottis. 22. Section of arytenoid muscle.]
The nasal cavities are separated from each other by a septum or
division wall composed of the perpendicular plate of the ethmoid bone
and the vomer posteriorly and the cartilaginous septum anteriorly, thus
presenting a smooth surface as the inner wall of each cavity. The floor
is formed by the palatine process of the superior maxillary bone and by
the palate bone, and runs in a slanting, downward direction from before
backward. The roof is formed by the nasal bones and nasal spine of the
frontal in front, in the middle by the cribriform plate of the ethmoid,
and posteriorly by the under surface of the body of the sphenoid bone.
Directly communicating with the nasal cavities are other cavities
situated in the bones of the skull, the lining mucous membrane of which
no doubt is largely affected by the pathological processes in nasal
diseases: these are the antra of Highmore, large triangular cavities
situated in the body of the superior maxillary bone and communicating
with the nasal cavities by an irregularly-shaped opening in the middle
meatus; {34} then the frontal sinuses, two irregular cavities situated
between the two tables of the frontal bone. The communication between
them and the nasal cavities is established by the infundibulum, a round
opening in the middle meatus, and finally the sphenoidal cells or
sinuses, found in the body of the sphenoid bone, communicating with the
nasal cavities by small openings in the superior meatus. That portion
of the nasal cavities which projects beyond the end of the nasal bone
is surrounded by cartilages forming the alæ of the nose.
In the cartilaginous septum of the lower animals we find a small cavity
lined with mucous membrane, called after its discoverer Jacobson's
organ, the minute anatomy of which has lately been described by
Klein.[18] This {35} organ in man is, however, only rudimentary. The
nasal cavities are lined with mucous membrane, which varies greatly in
thickness in different localities, and which materially decreases the
size of the cavities in the living subject from that seen in the
denuded skull. This mucous membrane is covered by ciliated epithelium
in man, with the exception of that portion which lines the
vestibule--_i.e._ that portion of the cavity of the nose surrounded by
cartilage only--which is covered by pavement epithelium.
[Footnote 18: _Quarterly Journal of Mic. Science_, January, 1881.]
In the lower animals we find that in the olfactory region the ciliated
epithelium is either absent, or that ciliated and non-ciliated
epithelium alternates in patches.[19] The author has not been able to
find a statement in the literature on the subject as to the kind of
epithelium found in the accessory cavities in man, but it is very
probable that the mucous membrane of the frontal sinuses and the antra
of Highmore is covered with ciliated epithelium; otherwise it would be
difficult, if not impossible, for the secretions of that mucous
membrane to pass through the narrow channels into the nasal cavities.
The color of the normal nasal mucous membrane is of a light pink shade
in what is termed the respiratory portion, while it is of a yellowish
hue in the olfactory region, that portion of the mucous membrane which
covers the roof and the outer walls of the nasal cavities down to the
upper margin of the middle turbinated bone and the septum down to about
the same level. It is in this region that the nerve-ends of the
olfactory nerve are distributed. Immediately beneath the mucous
membrane, and between it and the periosteum of the bony walls and the
perichondrium of the cartilaginous portion of the septum, we find a
tissue which bears a striking resemblance to the erectile tissue of the
genital organs.[20] It is composed of a network of fibrous tissue, the
trabeculæ of which contain a few organic muscular fibres. Its meshes of
various sizes and shapes are occupied by venous sinuses lined with
endothelium. These are supplied with blood by small arterioles and
capillaries, which are quite numerous in the fibrous tissue and can
readily be demonstrated under the microscope. In this arrangement of
elements of the nasal mucous membrane we find a ready explanation of
the fact that liquids of greater or less density than the serum of the
blood when introduced into the nasal cavities produce pain, for we have
here the most favorable conditions for osmosis, which will cause either
a contraction or a distension of the sinuses. In the larger masses of
fibrous tissue between the sinuses or caverns we find imbedded the
glands, with their ducts opening out between the epithelial cells of
the mucous membrane. There are two kinds of glands in this region,
which have been described by Klein[21]--viz. serous and mucous glands.
[Footnote 19: Haenle, _Anatomy des Menschen_, vol. ii.]
[Footnote 20: Haenle, _loc. cit._]
[Footnote 21: _Loc. cit._]
This cavernous erectile tissue is most abundant at the lower portion of
the septum and of the lower turbinated bones; and, although it has been
recognized and described as true erectile tissue by Haenle, Virchow,
and others, yet to Bigelow of Boston belongs the honor of having first
called attention to the part which this tissue plays in nasal diseases.
He gave to it the name turbinated corpora cavernosa.[22] The expansion
of the nasal cavities formed by the alæ of the nose is termed the
vestibule, which is lined with pavement epithelium and forms the
entrance to the cavities proper. The naso-pharyngeal cavity extends
from the posterior ends of the turbinated bones and the edge of the
vomer to the line where the velum palati touches the pharyngeal wall
during the act of deglutition or phonation. In this cavity we find the
openings of the Eustachian tubes, two crater-like elevations, with a
pit-like depression of variable size and shape, one on either side; and
a collection of glands with a central duct-like opening disposed on the
roof and posterior wall of the cavity. This gland was named by
Luschka[23] the pharyngeal {36} tonsil. The openings between the edge
of the vomer and the lateral walls of the naso-pharyngeal cavity are
termed the posterior nares.
[Footnote 22: _Boston Med. and Surg. Journal_, April, 1875.]
[Footnote 23: _Der Schlundkopf des Menschen_.]