deep-seated and gradually increasing pain and tenderness on pressure
over the sternum; but it may be a sense of constriction and oppression
with boring or throbbing sensations. Sometimes there is merely a sense
of uneasiness about the chest, with pains of a rheumatic or neuralgic
character in the shoulders or neck, brought about by irritation of the
intercostal and humeral nerves. The general health may be impaired, and
irritation of the pneumogastrics may be manifested by dyspepsia,
nausea, vertigo, syncope, headache, dyspnoea, and inability to lie
down. Laryngeal irritation is shown by cough, or spasm, with dryness of
the throat; a frothy mucus may be expectorated, with occasional rigors,
sweatings, and irregular febrile movement. When abscess follows severe
injuries, such as fracture or wounds, distinct evidences of phlegmon
appear, possibly within a week, accompanied by intermittent fever with
rigors, and a sense of weight and oppression in the front of the chest,
with pain in coughing and drinking, or breathlessness, "as if one had
been running" (Petit).
The pressure symptoms of mediastinal abscess are never so grave as in
other forms of mediastinal tumor, since the diffluent contents of an
abscess occasion less compression of the mediastinal viscera, or when
the intra-thoracic tension is excessive it seeks a channel by which the
pus is evacuated. The pressure symptoms are least marked when the
abscess is located in the anterior mediastinum.
There may be, on inspection, a distinct prominence over the upper part
of the sternum, with or without redness or oedema. Palpation may enable
one to recognize fluctuation on the borders of the sternum with
tenderness. The tumor may pulsate, but the pulsation never acquires the
expansile character of aneurism. Dulness on percussion may be marked,
and, according to Daudé, the dulness under the sternum may undergo a
change by alteration of the position of the patient. The heart sounds
may be heard distantly and indistinctly. The respiratory murmur may be
whistling over the region of the trachea, and in the chest a few moist
râles may indicate venous congestion, with exudation into the bronchial
passages; otherwise the condition of the lungs will probably be normal.
The entire series of pressure symptoms common to intra-thoracic growths
may be present, especially if the {863} posterior mediastinum is
invaded, and may correspond with those of mediastinal tumors in
general.
DURATION AND PROGNOSIS.--The causal relations of abscess in the
mediastinum are so various that it is only possible to decide the
question of duration after weighing the possibilities of treatment. The
persistence of the abscess is also decidedly governed by the
thoroughness of the drainage after opening has been affected.
The PROGNOSIS depends upon the etiology and the fulfilment of the
indications for treatment by drainage. Pressure on the heart and the
great vessels which proceed from its base, the descending aorta,
oesophagus, the pneumogastrics, and the internal thoracic circulation,
must be considered as complications adverse to a favorable prognosis
unless speedy relief is possible. Prominent pressure symptoms indicate
an implication of the intra-thoracic glandular system.
COMPLICATIONS, TERMINATION.--The abscess may open into any of the
internal viscera--the trachea, bronchi, or oesophagus. A favorable case
terminating by rupture into the latter passage is reported by Bennett.
At first a teaspoonful of bright fluid blood was coughed up, and the
day following from two to three ounces of purulent matter followed. The
discharge of pus continued five weeks, the sternal swelling subsiding
pari passu.
The pleura and pericardium have both been recorded as points of outlet.
The pus can even sink down into the inguinal or lumbar region.
Spontaneous external opening is said to occur most frequently on a
level with the second rib to the left of the sternum.
DIAGNOSIS.--The differential diagnosis between abscess and other
mediastinal growths will be considered in the section on Mediastinal
Tumors.
TREATMENT.--The exploratory puncture is to be recommended if a
fluctuating tumor appear presenting the general symptoms of abscess.
Rest, local sedative applications, and the relief of pain are positive
indications. Petit, Agnew, and others have applied the trephine to the
sternum in search of pus, with a satisfactory result. It is, however,
generally conceded that it is better to wait until pointing occurs, as
the area of the sternum is so limited that in all probability matter
forming behind it would speedily make its way to the surface in an
intercostal space at one of the margins of the bone. If the abscess be
deeper or due to scrofulous or syphilitic caries of the sternum, the
matter which forms may escape into the neck or through perforations of
the bone. The latter may be congenitally present or due to disease.
Caries, necrosis, or fracture of the bone may make trephining
obligatory, or the same indication may prevail if a dependent flow of
pus sufficient to drain the cavity is not otherwise obtainable.[6]
[Footnote 6: Chassaignac, _Traité de la Suppuration_, tome ii. p. 330.]
A similar line of treatment would be indicated if there was no tendency
to external pointing, and evacuation into the viscera seemed
threatened.
Excision of the whole or part of the sternum for abscess, cancer, or
other causes seems to have been fairly successful. Heyfelder[7] had
collected, in 1863, 18 established cases, in which there were 17
recoveries and 1 death.
[Footnote 7: _Traité des Resections_, traduit de l'Allemand avec
Additions et Notes, par le Docteur Boekels, Strasburg et Paris, 1863.]
Adhesions usually prevent a double pneumothorax, even when the sternum
and ribs have been resected. Unilateral pneumothorax is not necessarily
fatal.
Mediastinal Tumors.
ANATOMY.--The mediastinum is the space which the two pleural sacs leave
between them in the antero-posterior plane of the chest, and which
{864} contains all the thoracic viscera except the lungs. It is
subdivided into three parts--the anterior, middle, and posterior
mediastinum. A superior mediastinum has also been described. The space
between the pleural sacs occupied by the heart enclosed in the
pericardium, the vena cava superior, the ascending aorta, the pulmonary
arteries and veins, the phrenic nerves with their accompanying
arteries, and the bifurcation of the trachea and roots of the lungs
with some bronchial glands, takes the name of the middle mediastinum.
The anterior mediastinum is narrow in the middle, where the edges of
the lungs nearly meet, wider above, where the lungs diverge, and widest
of all below, for the same reason. It is very shallow from before
backward, and it is limited posteriorly by the anterior layer of the
pericardium, in front by the sternum, with the fifth, sixth, and a
small portion of the seventh costal cartilages, and by the triangularis
sterni muscle. The region is occupied simply by connective tissue, save
in its upper part, where lies, when it still persists, the shrivelled
remnants of the thymus body. It also contains a few lymphatic glands
and the left internal mammary artery and vein.
The superior mediastinum is bounded by a plane passing through the
lower part of the body of the dorsal vertebra behind and the junction
of the manubrium and the gladiolus in front. Its upper limit
corresponds to the superior aperture of the thorax. The contents of
this space are the transverse portion of the arch of the aorta and its
three large branches, the trachea and oesophagus, the thoracic duct,
the innominate veins, upper part of the superior vena cava, left
recurrent laryngeal nerve, phrenic, pneumogastric, and cardiac nerves,
with lymphatic glands and remains of the thymus body.
The posterior mediastinum is triangular in shape, placed in front of
the lower border of the fourth dorsal vertebra downward, and bounded
anteriorly by the pericardium and roots of the lungs. The lateral
boundaries are formed by the pleuræ. The space contains the descending
thoracic aorta: in front of the aorta the oesophagus with the
pneumogastric nerves, the left in front, the right behind. On the right
of the aorta is the vena azygos major; between this vein and the aorta
is the thoracic duct; superiorly is the trachea; inferiorly are the
splanchnic nerves and the posterior mediastinal lymphatic glands.
DEFINITION.--There are three principal forms of morbid growths in the
mediastina--sarcoma, lymphoma or lymphadenoma, and carcinoma.
Hyperplasia of the mediastinal glands also may arise, intertwined with
various diseases, such as phthisis (especially the form known as
pneumonic), pertussis, aneurism, rachitis, and syphilis. Enlargement of
the lymphatic glands may occur in connection with the scrofulous
diathesis, or similar enlargement associated with primary subacute or
chronic bronchitis and the varieties of catarrhal fever and influenza.
Allusion in this place will only be made to the rare instances in which
uncomplicated enlargement of the thoracic glands occurs in the
mediastinal spaces. Aneurism, abscess, and pericardial effusions will
be referred to only in so far as they affect differential diagnosis.
Mediastinal tumors, however, include certain forms which have the
interest of pathological curiosities rather than possessing a clinical
importance. Cysts in this region are rare, mostly of embryonic origin
(dermoid), and contain epithelial structure, such as hair, sebaceous
and sweat-glands, teeth, and occasionally bone, cartilage, and other
tissues. These cysts often develop rapidly and may attain great size.
Lipomata[8] occur as the result of an undue increase of the mediastinal
fat, and are associated with accumulation of the same in the
pericardium and in the system at large. Such tumors are rare and of
very gradual development. Kronlein[9] has described a congenital lipoma
of the {865} anterior mediastinum in a child aged one year, which found
its way through an intercostal space and then rapidly increased in
size. Fibromata, osteomata, and enchondroma are also possible
mediastinal and pulmonary tumors, but are seldom met with. Exostoses
may form upon the internal surface, and gummata upon the anterior and
posterior surfaces of the sternum.
[Footnote 8: Reigel, _Virchow's Arch._, vol. xlix.]
[Footnote 9: Langenbeck, _Klinic_, p. 157.]
PATHOLOGY AND MORBID ANATOMY.--Pulmonary processes associated with
bronchial catarrh frequently lead to enlargement of the bronchial
glands, because, owing to the impervious character of the basement
membrane of the bronchial passages, the mucous and epithelial portion
of the exudation is expectorated, and that portion of the exudate which
occurs from the bronchial blood-vessels is absorbed and carried by
means of the pulmonary lymphatics to the bronchial glands. Tubercular
deposits frequently occur in the glands of the posterior, and much less
frequently in those of the anterior, mediastinum.
Independently of the above conditions, caseating bronchial glands have
been found as complications of scarlatina with nephritis or tubercular
meningitis. An interesting case of this condition has been reported as
following an abscess in the glands at the root of the neck as a sequel
to measles nine months before.[10] Riegel also mentions an instance in
which some of the mediastinal glands were enlarged to the size of hen's
eggs. The trachea was compressed at the point of bifurcation, so that
its calibre was reduced to one-third its natural size. This case was
free from other glandular enlargements. Coupland has described a case
in a boy four years of age, in whom the cervical glands were enlarged
and idiopathic hyperplasia of the bronchial glands was suspected.
Autopsy: On raising the sternum a collection of indurated glands was
found in the anterior mediastinum, and over the root of the right lung
one of these glands had broken down into a cheesy mass. A chain of
enlarged lymphatics accompanied the right bronchus. The largest caseous
mass had ulcerated through the trachea just above the origin of the
right bronchus by an aperture measuring half an inch along the axis of
the tube, while for half an inch above its lumen was compressed. In
this case the right lung was solidified and contained cheesy matter,
with a cavity at the apex. The father of the child had also suffered
from increase in the glandular tissues.
[Footnote 10: See _Path. Soc. London_, 1884.]
The historical literature of intra-thoracic morbid growths has been
exhaustively reviewed in a monograph by Cockle, but until within the
last fifteen years little attempt was made to separate mediastinal
tumors into definite groups.
Our present knowledge on this subject was first shaped by Virchow,[11]
since which period numerous cases have been recorded.
[Footnote 11: _Virchow's Archiv_, Bd. xciii. Heft 3.]
Sarcoma of the Mediastinum.--Primary sarcomatous growths are relatively
uncommon. In 7566 cadavers examined at the Marine Hospital at Kronstadt
there were found 158 malignant tumors, 127 being carcinomatous, the
other 31 being sarcomatous. In 24 cases reported by Kahnlich, 13
occurred in the anterior mediastinal region, and a similar location was
found in a case reported by the writer,[12] also in one instance
reported by West.[13]
[Footnote 12: _Philada. Med. News_, March 15, 1884.]
[Footnote 13: _Path. Soc. London_, 1883.]
The anterior mediastinal space is a favorite location for the origin of
the purely sarcomatous form of tumor. Sarcoma may arise from a
persistent thymus (as in cases reported by Gee, Church, and Powell),
from the parietal or visceral layers of the pericardium or pleura, from
the periosteum of the sternum, or from the mediastinal connective
tissue.[14]
[Footnote 14: Kahnlich, _loc. cit._, describes 13 as originating in the
connective tissue of the anterior mediastinum, 5 in the periosteum of
the sternum, and 1 in the pericardial substance.]
{866} [Illustration: FIG. 53. 1, tumor; 2, aorta; 3, right ventricle of
heart.]
In a disease of this rare nature we can best formulate an idea of the
character of the growths by the recital of a few typical cases. In an
autopsy made by the writer, on removing the sternum and cartilages they
were found to be adherent on the right side to a mass which occupied
the anterior mediastinum (see Fig. 53). The growth was seven inches
long, measuring from the sternal notch, and terminated in a somewhat
diffused thickening of the visceral pleura, which covered the anterior
margin of the upper and middle lobe of the right lung. The growth was
two and a half inches broad. It overlaid the aorta, pulmonary artery,
and the vessels of the neck. The calibre of the trachea was slightly
diminished. The glands of the neck were unaffected on either side. The
posterior mediastinal glands were very slightly enlarged along the
sides of the trachea and upper bronchi. Laterally, at the lower portion
of the growth, the pulmonary pleura was thickened at the line of
contact with the tumor, but the lungs were free from any traces of
disease. The new formation was of fibrous consistence, of a gray-white
color, and through its centre a softened tissue was found. Microscopic
examination showed the growth to be composed of medium-sized lymphoid
cells mixed with spindle-shaped cells, and imbedded in a homogeneous
stroma or a stroma which consisted of reticulated fibres and wavy
fibrous tissue. Other portions of the body were normal.
In West's case the tumor also occupied the anterior mediastinum,
extending toward the second left intercostal space. The mass was about
the size of a boy's head, soft, cellular, and adherent to the upper
lobe of the left lung; it also rose into the episternal notch and left
supra-clavicular fossa. The brachial plexus and vessels of the left
side, subclavian and carotid arteries, the jugular and innominate
veins, were imbedded in the tumor. The left bronchus and a portion of
the trachea were flattened. The left phrenic and left pneumogastric
nerves passed through the mass, and on dissection were found much
thickened as they ran through the tumor. The tenth nerve measured {867}
three times its normal diameter, and was pushed out of its course
nearly an inch from the carotid. The recurrent laryngeal was also
thickened; the right pneumogastric and phrenic nerves were not
involved. The heart lay beneath the tumor; nodules of the new growth
were found upon the anterior surface of the heart and along the vessels
issuing from it. No secondary deposit was found in the lungs except at
the margin of the left upper lobe, into which the tumor spread
directly. The spleen, liver, kidneys, and lumbar glands were normal.
Microscopic examination determined the growth to be a round-celled
sarcoma, the thickening of the nerves being due to infiltration by
similar small-celled growth.
In primary sarcoma of the mediastinum--and the same is true of
lymphadenoma--the invasion of the various intra-thoracic organs is
chiefly by continuity or direct spreading of the growth. The lymphatics
of the neck are very rarely implicated in this form of malignant
disease; and while in lympho-sarcoma the glands may be involved, they
are not so frequently as in cancerous processes. Sarcomata of the
mediastinum with implication of the lungs and pleura are more
frequently secondary processes; indeed, the lungs would seem never to
be the seat of primary sarcoma. The pleural tissues, however, may be
primarily involved. Lepine, Birch-Hirschfeld, Böhme, Eppinger, Schultz,
Greenish, and others have reported cases in which the growths were
abundantly distributed in the pleural tissues as primary formations.
The point of origin is believed to be either directly from the ordinary
connective-tissue cells or from the endothelium of the lymphatics.
Secondary sarcomata may form in the mediastinum or in the lungs within
a month or so long as a year after the removal of tumors from other
parts of the body, probably by metastasis prior to the removal. In some
of these cases the seat of original growth and the neighboring glands
may be entirely healthy.
In a typical case of multiple osteoid sarcoma of the lung reported by
West fleshy vegetations were found on the visceral pleura: upon the
parietal pleura, over the seventh rib, two inches from the spine and
growing from it, was a lobular spongy mass as large as an orange, but
perfectly disconnected with the parts beneath. The right lung was
irregular in shape, owing to the presence of masses of new growth in
its different parts. The middle lobe seemed almost completely converted
into the new growth. Between the lower lobe and the diaphragm, but
attached to the lung, was a mass the size of a cricket-ball, covered
with a dark, laminated, but easily separated coagulum. The tumor
occupied the upper lobe of the left lung, forming an irregular oval
mass six by four and a half inches. It was white in color, and adherent
to its upper border was compressed lung-tissue. There were also four or
five independent nodules situated near the surface, and of a white
color. The lower lobe contained one medium-sized growth and four or
five small ones. The bronchial glands were not involved. The tumors
appeared soft and spongy, but on incision they were found so hard that
a knife could scarcely divide them.
Frequently, the lungs are found infiltrated with sarcomatous nodules of
a soft consistency, varying in size from a walnut to an orange. To sum
up: primary sarcomata may be the round- or spindle-celled variety; but
myeloid sarcomata also occur, chiefly as secondary growths. (See Fig.
54.)
[Illustration: FIG. 54. From photograph of a case of Professor Osler's,
showing secondary myeloid sarcoma of mediastinum--appearing six months
after removal of myeloid sarcoma of radius. The tumor figured in the
plate occupied the front of the thorax lying beneath the sternum and
the cartilages and ribs of the left side, pushing back and completely
covering the pericardium. It was loosely adherent to the ribs and
sternum, and appeared to grow from the pulmonary pleura, to which it
was attached in a large part of its extent, and only had penetrated the
lung at one spot on the anterior border of upper lobe. Right lung
contained secondary masses, chiefly in the pleura.]
Lympho-sarcoma of the Mediastinum.--Lympho-sarcoma, lymphoma, or
lymphadenoma is the form of malignant process which probably includes
the majority of cases of primary mediastinal growth. It is sometimes,
however, a part of a more general disease, affecting more or less the
whole glandular system.
{868} Murchison[15] classified the first case of this disease involving
the intestines, liver, mesentery, and heart. The same observer the
following year described a case in which the glands of the neck,
mediastinum, axillæ, and spleen were involved. Wunderlich has recorded
a case of malignant mediastinal disease which commenced in the glands
of the neck; but the cervical glands may be enormously enlarged without
implication of the bronchial.
[Footnote 15: _Path. Soc. Trans._, London, vols. xx. and xxi., together
with a summary of the literature of the subject.]
The general disease dates back to the time of Hodgkin, Bright, and
Wilkes, and was then known as anæmia lymphatica. It has been
specifically described by Virchow,[16] Cornil, and Ranvier as
independent of leukæmia, and was designated lymphadénie. It was noticed
by Trousseau under the title of adénie, and Ogle and numerous clinical
observers since have also recorded cases.
[Footnote 16: _Die Krankhaften Geschwülste_, Band ii. p. 376.]
As a mediastinal growth the characteristics of lympho-sarcoma can be
made more vivid by the reproduction of one of the first cases recorded
of this disease. On removing the sternum and cartilages they were found
adherent to a mass occupying the anterior mediastinum. The morbid
growth reached backward to the trachea, surrounding it with a thickness
posteriorly of a quarter of an inch; it extended downward to the
bifurcation of the trachea, and, involving the superior prolongation of
the pericardium, invaded and greatly thickened the parietal part of
that membrane, covering the heart at {869} its upper half. The diseased
structure reached upward to the root of the neck, involving the
anterior mediastinal glands, and surrounded the trachea by a thin layer
as high as the thyroid cartilage. Some of the glands on each side of
the neck were affected as high as the angle of the jaw. Laterally, the
morbid growth extended on each side to the line of junction of the
cartilages with their ribs, displacing the anterior margin of the lung.
The pulmonary pleura was involved and thickened at the line of contact,
and the right lung at the upper part of its anterior margin was invaded
from the pleura by white, fibrous-looking branched bands. At the lower
part of the anterior lobe the lung was also invaded from the
pericardium. Some of the glands at the root of the lung were involved
by extension, but they were not generally affected, nor was the lung
invaded except to the limited extent above mentioned. The heart and
pericardium were free from disease.[17]
[Footnote 17: Powell, _Path. Trans._, vol. xxi., London.]
The malignant growths of the mediastinal region implicate the
surrounding structures so rapidly that it is, as a rule, quite
impossible to determine, even after death, the starting-point of the
disease; and while lymphadenoma can originate in the same tissues as
the other forms of sarcoma already alluded to, yet it in most cases
probably originates in the lymphatics of the anterior or posterior
mediastinum.
In reference to the location of this form of morbid growth, we find, on
consulting a series of cases reported by Fenwick, Eve, Payne, Peacock,
Powell, Murchison, Bennett, Dickinson, that the region for principal
development seems to be the anterior mediastinal space, although in
several instances the posterior mediastinal region was also involved.