Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_2853_Библиотеки_им_академика_М_И_Перельмана
.pdf
156 CHAPTER 6: The Skin and Nails
https://t.me/medicina_free
Kaposi sarcoma. Human herpes virus type-8 infection is the cause. Endemic
disease in the Mediterranean and Africa can present with thickened scaling
skin, enlargement of the extremity, and ulceration. HIV infection greatly
increases the risk of developing KS in a pattern distinct from endemic disease. HIV-associated Kaposi sarcoma frequently involves the skin, mucous
membranes (hard palate) and viscera (lungs and gut). The initial lesions
are nonblanching, red-blue or bluish-brown papules, plaques, and nodules anywhere on the skin. Some lesions become spongy or compressible
tumors moving centripetally from the extremities. Lymphadenopathy and
lymphedema are late ndings. Iatrogenic immunosuppression in the setting of solid organ transplant also can be a risk factor for the development
of Kaposi sarcoma.
Cutaneous T-cell lymphoma—mycosis fungoides, Sézary syndrome.
are proliferations of malignant T-cells within the dermis and epidermis.
Mycosis fungoides lesions are indurated, often scaly and atrophic patches and
plaques reaching several centimeters in size. They are brown or pink and may
appear eczematous. The papules and plaques progress to nodules or large
masses, the tumor stage of disease. The disease is limited to the skin and
may be confused with eczema and psoriasis. Sézary syndrome is a systemic
disease with leukocytosis, lymphadenopathy, and skin inltration producing
erythematous indurated thickening of the dermis prominently of the face and
brows (leonine facies).
Metastatic cancer. The skin is the site of metastases from carcinomas or lymphomas. Breast, lung, and colon cancers, B-cell lymphomas, and metastatic
melanomas are particularly common in the skin. Any suspicious cutaneous
nodule or plaque should be biopsied.
These
Clinical Vignettes and Questions 157
https://t.me/medicina_free
CLINICAL VIGNETTES AND QUESTIONS
Case 6-1
A 54-year-old man presents with generalized erythroderma.
QUESTIONS:
1. What is the pathophysiology of generalized erythroderma?
2. What is the differential diagnosis of an adult with generalized
erythroderma?
3. What is erythema multiforme?
4. What are common causes of erythema multiforme?
Case 6-2
A 70-year-old man presents with tense bullae on his arms.
QUESTIONS:
1. What is the most likely diagnosis?
2. What condition may be confused with the correct diagnosis?
3. What is a Nikolsky sign?
A 33-year-old patient comes in with recurrent painful vesicles on the
lips. Each is umbilicated on an erythematous base.
QUESTIONS:
1. What is the most likely diagnosis?
2. What is the differential diagnosis for vesicular skin lesions?
You just nished examining a 60-year-old man with history of chronic
kidney disease stage 4 and severe hypoalbuminemia (secondary to
nephrotic syndrome from his recent diagnosis of multiple myeloma).
As you are walking out of the patients room you realize that you forgot
to examine his nails. You go back to the patients room to examine his
nails as they can give you some important clues regarding his condition.
QUESTION:
1. Describe Terry nails, Lindsay’s nails, Beau’s lines, Muehrcke’s
lines, and Mees’ lines and the signicance of each.
Case 6-3
Case 6-4
158 CHAPTER 6: The Skin and Nails
https://t.me/medicina_free
Case 6-5
You are examining a 50-year-old man with a 70-pack-year smoking history
and Chronic obstructive Pulmonary disease (COPD). You notice that he
has clubbing. On further questioning he states that he has lost 10 pounds
in the last 3 months.
QUESTIONS:
1. What condition should you be most concerned about in this
patient?
2. What is the differential diagnosis of new onset clubbing in adults?
Case 6-6
QUESTIONS:
1. What is the differential diagnosis of one or more cutaneous ulcers
associated with regional lymphadenopathy (the ulceroglandular
syndrome)?
2. What is the most essential investigation to narrow this broad dif-
ferential?
3. Describe the clinical ndings for syphilis, tularemia, and anthrax.
A 76-year-old man presents with a skin lesion on his face. You nd a
2-cm at indurated pink plaque with a rolled border.
QUESTIONS:
1. What is the most likely diagnosis?
2. Describe the key features of nonmelanoma skin cancers?
While examining a 46-year-old man suspected of having infective endocarditis, you remember that subacute bacterial endocarditis (SBE) can be
associated with Janeway lesions and Osler nodes.
QUESTIONS:
1. What are Olser nodes? Describe the pathophysiology.
2. What are Janeway lesions? Describe the pathophysiology.
Case 6-7
Case 6-8
CHAPTER 7
https://t.me/medicina_free
The Head and Neck
This chapter discusses symptoms, signs, and syndromes related to the head
and neck; trauma is not covered. At least nine specialties focus on the head
and neck, each developing detailed exams often utilizing specialized instruments. The exams described here are made with resources available to the
general clinician. Symptoms, signs, and syndromes primarily of neurologic
signicance are discussed in Chapter 14. By necessity, these distinctions are
somewhat arbitrary. During the head and neck examination the examiner
identies signicant abnormalities and identies signs of systemic disease.
As always, knowing the limits of one’s expertize and the indications for specialty referral are imperative.
MAJOR SYSTEMS OF THE HEAD AND NECK
The skull, facial bones, and scalp provide protection and insulation for deeper
organs. The scalp and face have a rich vasculature that vasodilates on cold
exposure to maintain normal temperature within vital organs. The head contains the organs of special sense: the eyes, ears, olfactory nerve, and taste buds.
Special senses are impaired by problems in the sensory organs, cranial nerves,
or brain. The tongue, pharynx, and larynx are organs of speech so structural or
functional problems alter articulation. The nose, mouth, pharynx, larynx, and
trachea form the upper airways. Compromised upper airways affect breathing
and voice tone and/or volume. The mouth, teeth, mandible, maxilla, tongue,
salivary glands, pharynx, and upper esophagus are the upper alimentary tract
necessary for mastication and swallowing. Together the upper airways and
digestive tract are the upper aerodigestive tract. The head and neck are highly
vascular. The external carotid has rich anastomoses supplying supercial
structures so ischemia is unusual. The internal carotid and vertebral arteries supply blood to the brain. The head and neck lymphatic network drains to
regional lymph node beds. The tonsils and adenoids are lymphatic organs
surrounding the upper aerodigestive tract. The neck contains the thyroid and
parathyroid glands, major structures of the endocrine system.
FUNCTIONAL ANATOMY OF THE HEAD AND NECK
The Scalp and Skull. The scalp has ve layers: the skin, subcutaneous connec-
tive tissue, epicranius, a subfascial cleft with loose connective tissue, and the
pericranium (Fig. 7-1). The outer three are a single thick, tough, and vascular
layer, whose strength is supplied by the epicranius. The epicranius is formed
by the frontalis muscle attaching to the occiput by a large central aponeurosis,
the galea aponeurotica. The skin and subcutaneous tissue are tightly bound to
the galea by brous bands that sharply limit the spread of blood or pus. The
159
160 CHAPTER 7: The Head and Neck
Loose connective tissue
https://t.me/medicina_free
Cutis
Galea aponeurotica
FIG. 7-1 Layers of the Scalp. For practical purposes, the cutis, subcutis, and galea aponeurotica constitute a single,
thick, tough layer with fibrous bands compartmentalizing the more superficial tissue and binding it to the galea. Between the
galea and the pericranium is a potential space with a little areolar tissue. Fluid and infection spread slowly through the compartments above the galea but spread easily t hrough the space beneath the galea and its at tached muscles (the epicranium).
The pericranium is the periosteal layer that covers the bones of the skull and dips inward at the suture lines. Subperiosteal
fluid is limited to the area over a single bone.
pericranium, the periosteum of the skull, dips into the sutures limiting spread
of subperiosteal blood or pus to the surface of a single bone. The subfascial
cleft between the pericranium and galea allows the scalp to be lifted off the
skull with minimal effort, allowing blood or pus to spreads widely beneath
it. A useful mnemonic is SCALP: Skin, Connective tissue, Aponeurosis, Loose
connective tissue, Periosteum.
The scalp has three lymphatic drainage areas. The forehead and anterior
parietal region drain to preauricular lymph nodes. The mid-parietal region
drains rst to postauricular nodes and then to nodes in the posterior cervical
triangle. The occipital area drains rst into nodes at the origin of the trapezius
and then into the posterior cervical triangle.
Subcutis
Pericranium
Bone
The Face and Neck: Facial contour is determined by the frontal bone (form-
ing the forehead and the brows), the maxilla and zygomatic arch (forming the
cheeks and inferior orbital rim), the bony and cartilaginous nose, external
ears, and mandible. The mandibles articulate with the temporal bone anterior
to the acoustic canal. Each ramus drops inferiorly to the angle of the jaw
where the mandible turns anteriorly and medially, the two halves meet in
the midline forming the chin. The upper and lower teeth contribute to the
vertical facial proportions. The bony superstructure is overlaid with muscles
and soft tissues, including the lips, giving the face its rounded contours. Mild
facial asymmetry is common. The anterior neck is dominated by the thyroid
cartilage, which is more prominent in men (the Adam’s apple), the cervical
trachea, and the two sternocleidomastoid muscles arising on the mastoid
process and inserting on the clavicle and manubrium. The posterior neck is
enveloped in thick longitudinal muscles covering the cervical spine from the
occiput to the upper back, and the fan-shaped trapezius forming the neck’s
posterior lateral contour.
The Ear: The pinna, or auricle, and the external acoustic canal compose the exter-
nal ear; the middle ear consists of the tympanic membrane (TM) and tympanic
cavity with its three ossicles. The internal ear, or bony labyrinth, is composed of
the cochlea (the organ of hearing) and semicircular canals (the organ for balance).
Functional Anatomy of the Head and Neck 161
External
acoustic
A. External Ear B. Sectional View of Ear
Pharynx
Malleus (hammer)
https://t.me/medicina_free
External ear. The pinna or auricle is a attened funnel with crinkled walls of
yellow broelastic cartilage. It has a wide external brim narrowing internally
to the external acoustic meatus. Several prominent folds have considerable individual variation (Fig. 7-2A). The helix originates as the crus coursing anteriorly and then winding up, back, and down posteriorly forming the funnel’s
brim. Above the midpoint of its posterior vertical portion, a fusiform swelling
occasionally develops, the Darwinian tubercle. An inner concentric fold, the
antihelix, partially surrounding an ovoid cavity, the concha, is divided into an
upper and lower portion by the transverse helical crus. From the anterior brim
of the funnel, below the crus a small eminence, the tragus, points back toward
the lower concha. From the lower portion of the antihelix, another eminence,
the antitragus, points forward to the tragus across the intertragal notch. The
deep lower concha forms the external acoustic meatus. At the junction of the
inferior limbs of the helix and antihelix is a pendant lobule of adipose and
areolar tissue without cartilage, the earlobe.
The external acoustic meatus or canal is ~2.5 cm long, extending from the
concha to the TM (Fig. 7-2B). The canal’s lateral third is walled by cartilage,
the medial two-thirds runs through the temporal bone. From the concha, the
canal forms a gentle S, tending inward, forward, and upward. Approximately
20 mm inside is a bony constriction, the isthmus. Ear wax produced in the
cartilaginous canal acidies and protects the epithelium by suppressing bacterial growth and capturing particles. The wax is moved to the concha by the
outward migration of the canal’s epithelium.
Middle ear. The acoustic canal widens within the temporal bone’s petrous
portion forming the tympanic cavity. Separating the tympanic cavity from the
external canal is the TM, an ovoid biconcave disk slanting across the canal in
a plane 35 degrees from vertical, its posterior superior portion is more supercial than the anterior inferior attachment (Fig. 7-2B). The manubrium of the
malleus is rmly attached to the inner TM. Viewed from outside, the attached
Darwin’s
tubercle
Crus
meatus
Helix
Antihelix
Concha
FIG. 7-2 Pinna and Middle Ear Anatomy. A. Surface of pinna: The main features are depicted, but there are
Tragus
Antitragus
Earlobe
many individual variations. Darwin tubercle is only occasionally present. B. Middle ear: A vertical section through the ear.
Note the flexible cartilaginous and fixed bony segment of the external acoustic meatus. The plane of the TM slants outward
~35 degrees from vertical; the conical apex points inward and upward.
Tympanic
membrane
Cartilaginous
meatus
Incus (anvil)
Stapes (stirrup)
Bony
meatus
Auditory tube
(eustachian t.)
Cochlea
162 CHAPTER 7: The Head and Neck
https://t.me/medicina_free
portion appears as a smooth ridge forming a radius of the membrane, slanting upward and slightly anterior.
Inner ear. The inner ear, or labyrinth, is within the temporal bone adjacent to
the middle ear. It consists of the spiral cochlea (the organ of hearing), the semi-
circular canals, ampullae, utricle, and saccule (organs of balance and position
sense of the head), and the acoustic nerve endings of CN-VIII. Two windows
connect the middle and inner ear: the oval window contains the footplate of
the stapes communicating mechanical vibrations to the inner ear via the scala
vestibuli; the round window covers the origin of the scala tympani.
The Eyes: The structural and functional anatomy of the eyes is complex, but
a basic understanding facilitates interpretation of visual signs.
Orbits. The bony orbits are quadrilateral pyramids with bases facing anteriorly
and apices pointing backward and medially. Their medial sides are parallel,
whereas the lateral walls form a 90-degree angle (Fig. 7-3). Seven bones form
each orbit. The frontal bone and lesser sphenoid wing form the orbital roof.
Portions of the ethmoid, maxillary, lacrimal, and sphenoid bones form the
medial wall containing the lacrimal groove for the lacrimal sac anteriorly. The
zygomatic bone and greater sphenoid wing form the lateral wall. The orbital
oor contains the maxillary, palatine, and zygomatic bones. Several foramens
open into the orbit. At the posterior apex within the lesser sphenoid wing is
the optic foramen leading into the optic canal containing the optic nerve (CN-II),
ophthalmic artery, and sympathetic nerves. The superior orbital ssure between
the sphenoid wings separates the roof from the lateral wall. It carries orbital
branches of the middle meningeal artery, the superior ophthalmic vein, and
four cranial nerves: the oculomotor (CN-III), the trochlear (CN-IV), the rst
(ophthalmic) division of the trigeminal (CN-V-1), and the abducens (CN-VI).
Eyelids. The palpebral ssure is the space between the opened lids. The two
angles where the lids meet are the lateral (temporal) and medial (nasal) canthi.
The caruncle, a small protuberance of modied skin, lies in the medial canthus
anterior to a tissue fold, the plica semilunaris. On each lid’s nasal margin is a
punctum opening into the superior or inferior canaliculi which meet to form
FIG. 7-3 Relationship of the Orbits and Globes. A horizontal section through the orbits. The medial orbital walls
are parallel. When the globes are in the primary position, the parallel optic axes are parallel with the medial orbital walls.
Because the orbital apices and origins of the ocular muscles are medial to the optic axes in the primary position, the lateral
rectus muscles are longer than the medial and the superior and inferior recti pull medially.
Lateral canthus
Pinguecula
Medial canthus
Functional Anatomy of the Head and Neck 163
https://t.me/medicina_free
the common canaliculus draining into the lacrimal sac. The upper lid extends
to the superior rim of the bony orbit merging there with the periosteum. The
skin covering the lids is the body’s thinnest skin and is readily moved and
picked up. During elevation the upper eyelid invaginates between the globe
and upper orbital border. The shorter lower lid extends inferiorly from the lid
margin to merge with the periosteum of the inferior orbital rim. It does not
infold. The lids’ tight orbital rim attachments limit uid movement into or
out of the orbit. The lids contain circular bers of the orbicularis oculi muscle
innervated by the facial nerve (CN-VII). The upper lid also contains vertical
tendons of the levator palpebrae superioris muscle, which originates in the optic
foramen and inserts into the tarsal plate. The levator palpebrae is innervated
by the oculomotor nerve (CN-III). In the upper lid posterior to the levator is
Müller muscle innervated from the cervical sympathetic chain. The lids are
stiffened by dense transverse connective tissue plaques, the tarsal plates,
which adhere posteriorly to the palpebral conjunctiva. The lids contain mei-
bomian glands emptying through pinpoint openings in the lid margins. On the
lid margins where the conjunctiva and skin meet is a double row of deeply
pigmented eyelashes curving outward. Deep to the temporal side of the upper
lid, beneath the frontal bone, lies the tear-producing lacrimal gland. Numerous
accessory lacrimal glands within the conjunctiva provide baseline tear production. The epicanthal fold is a vertical semicircular skin fold over the nasal lids
that partially covers the medial canthus. It is present in ~20% of white newborns but disappears in 97% by the age of 10 years. The epicanthus must be
distinguished from the horizontal skin fold in Asian patients that originates
in the upper lid and variably overhangs the superior lid (Fig. 7-4).
Conjunctiva. The palpebral conjunctiva follows the inner lid from the lid
margin into the superior and inferior fornices. In the fornices the conjunctiva
reects covering the sclera as the bulbar conjunctiva. The conjunctiva is rmly
attached to the tarsal plates but is quite loose in the fornices permitting globe
movement. The larger peripheral episcleral vessels are visible through the bulbar conjunctiva and slide over the sclera with the conjunctiva. The conjunctiva attaches rmly to the sclera at the corneal limbus. Arising from limbal
stem cells the corneal epithelium differs from the conjunctiva. The supercial
vessels of the bulbar conjunctiva are radial and tortuous (Fig. 7-33A). The
deeper vessels radiate near the limbus and are not normally visible. On either
Limbus
Cilia
FIG. 7-4 External Landmarks of the Normal Right Eye.
Pilica semilunaris
Caruncle
Punctum
164 CHAPTER 7: The Head and Neck
https://t.me/medicina_free
side of the limbus is commonly found a raised horizontal yellow plaque, the
pinguecula, caused by sun damage to conjunctival elastic tissue.
Cornea. The clear convex cornea has ve transparent avascular layers through
which the anterior chamber, iris, pupil, and lens are inspected. The cornea
joins the sclera at the limbus. The anterior chamber between the endothelial
surface of the cornea and the iris lls with aqueous uid produced by the
ciliary body. The uid drains peripherally through the anterior chamber angle
at the circumferential junction of the iris and cornea. The cornea and anterior
eye are best examined by slit lamp which allows visualization of individual
cell layers.
Sclera. Beneath the bulbar conjunctiva the globe is covered by a tough, dense,
avascular brous coat, the sclera. It is china-white except for brown melanin
spots varying in number with complexion and race. Piercing the sclera is the
scleral foramen for the optic nerve, long ciliary arteries and nerves, short ciliary
nerves, and venae vorticosae. The ocular muscle tendons insert into the sclera.
Iris and pupil. The iris is a muscular diaphragm of radial dilating muscle,
the dilator pupillae, and a central circumferential muscle, the sphincter pupillae,
surrounding the aperture for light, the pupil. These muscles control the pupil’s
size regulating the amount of light passing through the lens to the retina.
Lens. Behind the iris, the exible transparent crystalline lens focuses light on
the retina. The convex anterior and posterior surfaces join at the equator. The
lens is suspended from its equator by the zonula ciliaris inserting into the cili-
ary body (Fig. 7-5). For distant vision the eye is at rest, the ciliary muscle relaxing increases tension on zonula attening the central lens and decreasing its
refractive power. The lens accommodates to near focus by contracting the ciliary muscle which decreases tension on the zonules allowing the elastic lens
to become more spherical increasing its refractive power.
Vitreous body. The vitreous is the clear gelatinous tissue behind the lens
attaching circumferentially to the peripheral pars plana and retina (vitreous
base) and posteriorly to the optic nerve head, vessels, and macula. The vitreous partially liquees with age. Traction at the vitreous base can tear the
retina, allowing liquid vitreous into the subretinal space causing a retinal
detachment. In ischemic retinal disease the vitreous is a scaffold for brous
tissue and proliferating blood vessels which can contract tearing the retina.
Retina, choroid, and optic nerve. The posterior ocular segment is best considered from the inside out. The retina loosely lines the inner globe, attaching
FIG. 7-5 Cross-Section of the Lens and Ciliary Body.
Functional Anatomy of the Head and Neck 165
https://t.me/medicina_free
anteriorly to the peripheral ciliary body at the pars plana. The retinal nerve
ber layer coalesces to form the optic nerve which exits the globe through a
lattice-like opening in the posterior sclera, the lamina cribrosa. The central retinal artery and vein course within the optic nerve branching onto the retina to
form superior and inferior temporal arcs around the macula. The center of
the macula, the fovea, is for detailed vision. The nasal retina, supplied by the
nasal vascular arcades, provides indistinct temporal peripheral vision. The
retinal pigment epithelium shuttles nourishment and waste between the overlying retinal ganglion cells and underlying choroid containing net-like blood
vessels. External to the choroid is the brous sclera.
The Nose: The external nose is a pyramid joined to the face on one side
(Fig. 7-6). The root connects to the forehead and the sides join in the midline forming the dorsum nasi whose superior portion is the bridge of the nose.
The tip of the nose is the pyramid’s apex. The triangular base is pierced on
both sides by an elliptic orice, the naris (plural nares), separated in the midline by the columella, an extension of the nasal septum. Still hairs, the vibrissae,
line the margins of the nares inhibiting foreign body inhalation. Each lateral
surface ends inferiorly in a rounded eminence, the ala nasi (plural, alae nasi).
The upper third of the lateral nasal walls are supported medially by the nasal
bone and laterally by the nasal process of the maxilla. The lower two-thirds
is supported by the greater alar cartilage and several lesser alar cartilages. The
nasal passages are separated anteriorly by the cartilaginous nasal septum and
posteriorly by bone, the vomer.
The nasal septum divides the nasal cavity into symmetrical air passages
that begin anteriorly at the naris (Fig. 7-7), widen into a vestibule, then become
a high, narrow passage ending posteriorly at an oval orice opening into
the nasopharynx, the choana. A vascular network on the anterior nasal septum, Kiesselbach plexus, is the site of most nosebleeds. The central septum is
a vertical plane. The lateral walls contain three horizontal, parallel, downward curving bony plates, the superior, middle, and inferior turbinates or con-
chae. The inferior turbinate’s mucous membranes are highly vascular and
semi-tumescent. Vasoconstrictor drugs reduce blood ow thereby decreasing
tumescence. Under each turbinate is a groove, the superior, middle, and inferior
meatus. The olfactory nerve (CN-I) endings are above the superior turbinate.
Superior and posterior to the superior turbinate is the opening of the sphe-
noid sinus. The superior meatus contains the orices of the posterior ethmoid
FIG. 7-6 The External Nose. These diagrams show the topographic features and the skeleton. Note that the proximal
half of the nose is bone and the distal half (stippled) is cartilage.
Соседние файлы в папке Библиотека им академика М.И. Перельмана