EYELIDS

From Big Medical Encyclopedia

EYELIDS (palpebrae) — two folds of skin closing an eyeglobe at a smykaniye. Protect an open surface of an eye from an adverse effect of the environment century and promote uniform moistening of a cornea and conjunctiva.

Anatomy

Fig. 1. Cartilages, ligaments and nerves century: 1 — ramus lateralis n. supraorbitalis; 2 — ramus medialis n. supraorbitalis; 3 — n. infratrochlearis; 4 — saccus lacrimalis; 5 — processus frontalis maxillae; 6 — lig. palpebrale mediale; 7 — rima palpebrarum; 8 — maxilla; 9 — n. infraorbitalis; 10 and 16 — septum orbitale; 11 — bottom edge of a cartilage of a lower eyelid; 12 — .tarsus inf.; 13 — lig. palpebrale lat.; 14 — tarsus sup.; 15 — the upper edge of a cartilage of an upper eyelid.

Upper V.'s border is planned brovyo, and lower — approximately bottom edge of an eye-socket. Connecting with each other, V. form medial and lateral corners of an eye (anguli oculi med. et lat.) and commissures of B. (commissurae palpebrarum med. et lat.). B. limit an intercentury palpebral fissure (rima palpebrarum). B a medial corner of this crack is located the lacrimal lake (lacus lacrimalis), and at the bottom of it — the lacrimal meat (caruncula lacrimalis). The form B. is defined by their firm basis — top and bottom cartilages (tarsi sup. et inf.), consisting of very dense connecting fabric (fig. 1). By means of two strong horizontally located sheaves — medial (lig. palpebrale med.) and lateral (lig. palpebrale lat.) V.'s cartilages are attached to edges of a bone eye-socket. In addition to these sheaves, cartilages are connected to a periosteum of an eye-socket on all orbital edge a tarzo-orbital fascia (fascia tarsoorbitalis), edges is interwoven into a front surface of cartilages.

Fig. 2. Vertical section of an upper eyelid: 1 and 20 — pars palpebralis m. orbicularis oculi; 2 — the bunches of m. levator palpebrae superioris going to skin of a century; 3 — m. levator palpebrae superioris; 4 — m. tarsalis sup.; 5 — arcus palpebralis sup.; 6 — - gl. lacrimales accessoriae; 7 — area of the upper edge of a cartilage; 8, 9 — gl. tarsalis; 10 — arcus palpebralis inf.; 11 — the arterial branch leaving it; 12 and 15 — m. ciliaris (Riolani); 13 — limbus palpebralis post.; 14 — tunica conjunctiva; 16 — gll. ciliares; 17 — gll. sebaceae; 18 — limbus palpebralis ant.; 19 — cilia; 21 — a bag of a hair; 22 and 23 — thin hairs of skin.

In centuries it is accepted to distinguish two layers, two plates: superficial (lobby) — musculocutaneous, consisting of skin and a hypodermic muscle, and deep (back) — conjunctival and cartilaginous, consisting of a cartilage and conjunctivas (see), covering a cartilage behind (fig. 2). The border between these two plates is visible at free edge of V. in the form of the grayish line located ahead of numerous points — the openings put in the thickness of V.'s cartilage — meibomian glands (gll. tarsales — glands of a cartilage a century). The front plate of V. bears on itself eyelashes (cilia) — 100 — 150 on upper V. and 50 — 70 — on lower. Near the theory of eyelashes sebaceous glands are stuffed up (gll. sebaceae), and between them modified stalemate — ciliary glands (gll. ciliares). On the edge of top and bottom V. at a medial corner of a palpebral fissure the lacrimal openings (puncta lacrimalia) representing the beginning of the lacrimal tubules (canaliculi lacrimales) lie.

V.'s skin is thin, hypodermic cellulose very friable; all this does V.'s skin easily movable that is widely used at plastic surgeries easy developing of hypostasis of V. at local inflammatory processes (e.g., barley) speaks V. Rykhlostyyu of hypodermic cellulose, at frustration local (in particular venous) blood circulations, a Quincke's disease of Quincke, fibrinferment of a cavernous sine, and also at some general diseases (a disease of kidneys, etc.).

Under V.'s skin a part of a circular muscle of an eye is put (pars palpebralis m. orbicularis oculi) which, being reduced, closes V. (closes an eye). Short periodic reductions provide it the blink movements. As a part of a circular muscle there is small, but functionally important part — lacrimal (pars lacrimalis). It is related to the mechanism of a slezoprovedeniye: at periodic reductions and relaxations (in the act of a blinking) provides alternate narrowing and expansion of a dacryocyst. Among fibers of a circular muscle the group of the fibers located between roots of eyelashes — m. Riolani is described; reduction of these fibers promotes removal of a secret of glands of a cartilage a century.

The circular muscle of an eye is innervated by a facial nerve (n. facialis). Also the muscle raising an eyelid can be carried to V.'s muscles (m.levator palpebrae sup.), edges, beginning in the depth of an eye-socket near the visual channel (see. Eye-socket ), goes under an upper wall of an eye-socket and terminates in the thickness of upper V. in three portions: two of them (front, or superficial, and back, or deep) are tendinous, and average (a part deep) — muscular. The last, presented by a thin coat of smooth fibers (m. tarsalis sup. or m. Mulieri), is interwoven into the upper edge of a cartilage and innervated from a cervical part of a sympathetic trunk, all other muscle (cross-striped) is innervated by a third cranial nerve. The front portion of the muscle lifting upper V. gets under upper V.'s skin, and back goes to an upper fornix conjunctiva. Such triple termination of a muscle provides a possibility of the joint movement of upper V. in general — a cartilage (an average portion of a muscle), skin (a front portion) and conjunctivas (a back portion of a muscle).

In the lower V. there is no special «opuskatel», however to the tendinous fibers going from a vagina of the lower direct muscle of an eye to the lower V.'s thickness (always existing), smooth muscle fibers are often added (m. tarsalis inf.).

The sensitive innervation of upper V. is carried out at the expense of the I branch of a trifacial (n. ophthalmicus), its final branches: medial and lateral branches of a supraorbital nerve (rami med. et lat. n. supraorbitalis), supratrochlear (n. supratrochlearis), subblock (n. infratrochlearis) and lacrimal (n. lacrimalis). The lower V. receives a sensitive innervation generally from infraorbital, from the II branch of a trifacial (n. infraorbitalis). The lacrimal nerve, the interior — subblock takes part in an innervation of an outside part of the lower V.

Have well developed arterial network presented by the numerous and richly anastomosing among themselves vessels coming from system of an orbital artery (a. ophthalmica) and from system of facial arteries century (a. facialis, a. temporalis superficialis; and. infraorbitalis). The most important arterial branches are so-called arterial arches (arcupalpebrales sup. et inf.), V. put in the thickness of a century on a front surface of a cartilage, a supraorbital artery (a. supraorbitalis), lateral and medial arteries of V. (aa. palpebrales lat. et med.) and infraorbital artery (. infraorbitalis).

The numerous veins of V. which are mostly accompanying arteries are located usually in two layers: the surface layer — is located immediately under V.'s skin, deeper — on a front surface of a cartilage. Outflow of a venous blood comes from fabrics B. partly in system of facial veins, partly in system of orbital. A venous anastomosis between veins of the person and an eye-socket has important clinical value. One of such largest anastomosis is the so-called angular vein (v. angularis) which is located under V.'s skin at a medial corner of an eye.

Limf, vessels of area of upper V. fall in limf, the nodes located ahead of an auricle; limf, the lower V.'s vessels go to submandibular limf, nodes, hl. obr. to group of the nodes located at the level of a corner of a mandible.

Pathology

Symptomatology

At V.'s diseases is shown a number of the signs having differential and diagnostic value.

Hemorrhages under skin or in V.'s thickness result from their injury or a fracture of base of the skull. At V.'s injury hemorrhage develops soon after an injury, and at a fracture of base of the skull — in 12 — 36 hours after an injury and happen, as a rule, bilateral (so-called blood points). Usually blood resolves within several days.

Hypostases usually are a century a symptom of any disease of an eye or the fabrics surrounding it and can be inflammatory and noninflammatory character. Inflammatory hypostases are observed much more often (at barley, V.'s abscess, phlegmon of a dacryocyst, acute inflammations of a conjunctiva or the eye); noninflammatory hypostases are observed at a serious illness of kidneys and hearts and usually are followed by hypostases of other areas of a body. The special form is represented by a Quincke's disease of V. (at a Quincke's edema). Treatment is directed to elimination of the main reason for a disease.

Emphysema of Century. develops as a result of hit of air under V.'s skin at disturbance of an integrity of walls any of adnexal bosoms of a nose as a result of an injury. The typical symptom of emphysema — crepitation at V. Rassasyvaniye's palpation of air occurs independently within several days.

Dyskinesia — functional disturbance — lack of ability to close one eye separately while the bilateral smykaniye of V. is carried out normally; it is observed in most cases at children.

Diseases

Blepharophimosis — shortening of a palpebral fissure, most often happens because of accretion of edges of V. at an outside corner of an eye after hron, inflammations of a conjunctiva. Treatment surgical. Prevention — persistent treatment of conjunctivitis.

Herpes simplex — viral disease. It is characterized by emergence on V. of the serous bubbles further disappearing completely.

Herpes zoster — much more severe form of a disease, arises during the involvement in process of a trifacial and is expressed in a rash of bubbles on the course of its peripheral branches, is followed by severe pains. Bubbles at first serous, and then purulent, dry up with formation of a crust, after rejection a cut on skin there are scars; the affected skin long keeps a hyposensitivity. Treatment: salicylates, vitamins of group B, at severe pains — analgetics.

Fig. 3. Contagious mollusk century.
Fig. 4. Neurofibroma of an upper eyelid. Hypostasis of a lower eyelid is expressed.

Contagious mollusk. The activator — a virus; the disease is especially infectious at children. On V. there are whitish small knots (fig. 3) at top of which there is impression. Treatment — opening of small knots and a scraping of their contents an acute spoon. Prevention — observance necessary a dignity. - a gigabyte. conditions.

Madaroz — lack of eyelashes with a thickening of ciliary edge of V., usually owing to is long the proceeding ulcer blepharitis. Eyelashes do not grow again.

Trichiasis — the wrong growth of eyelashes after diseases of edges of V. or a mucous membrane. In case of friction of eyelashes on an eyeglobe their enucleating together with a hair bulb, and sometimes even carrying out special operations is necessary.

Eczema of skin century can be becoming wet with education on V. of bubbles, pustules after which opening the becoming wet surface is bared, or scaly with a plentiful peeling of V. Razvivayetsya at a scrofula (at children), disorders of exchange, conjunctivitis with plentiful separated, sometimes owing to intolerance of medicamentous drugs (Dicainum, atropine, etc.). Treatment: lotions with resorcin (at the becoming wet eczema), pastes with zinc oxide, mercury ointments (see. Eczema ).

Angiomas — single or multiple high-quality vascular educations, usually inborn. Treatment — excision, coagulation or a roentgenotherapy.

Carcinomas are malignancies and meet more often in the form of bazalnokletochny cancer and a melanoblastoma. The last quite often develop from birthmarks. Treatment — surgical or beam, quite often combined.

Cysts dermoid are located at internal or outside commissure of V. in the field of bone seams; represent the roundish, dense and elastic educations soldered to the subject periosteum and not soldered to skin. Treatment — surgical.

Serous cysts have an appearance of transparent bubbles on the edge of V. size from a pin head to a pea; develop as retentsionny cysts from sweat glands. Treatment — opening of bubbles or their removal.

Neurofibroma — soft, a pasty consistence the tumor (fig. 4), in the thickness a cut are probed knotty dense tyazh. Treatment — surgical.

Other diseases a century — see. Ankyloblepharon , Blepharitis , Nictitating spasm , Blepharochalasis , Ectropion of a century , Torsion of a century , Conjunctivitis , Ksantelazma century , Lagophthalmia , Ptosis , Trachoma , Chalazion , Epikantus , Barley .

Operations on centuries — see. Blepharoplasty , Blepharorrhaphy , Canthoplasty , Canthotomy .


Bibliography: Krasnov M. L. Elements of anatomy in clinical practice of the ophthalmologist. page 28, M., 1952; Merkulov I. I. Clinical ophthalmology, book 1, page 5, Kharkiv, 1966; The Multivolume guide to eye diseases, under. edition of V. N. Arkhangelsky, t. 1, book 1, page 178, M., 1962, t. 2, book 1, page 9, M, 1960; Der Augenarzt, hrsg. v. To. Velhagen, Bd 1, S. 99, Lpz., 1969; Kronfeld P. G., M and with H u g h G. a. P o 1 at a k S. L. The human eye in anatomical transparencies, p. 35, N. Y., 1945; System of ophthalmology, ed. by S. Duke-Elder, v. 2, p. 499, L., 1961, bibliogr.

M. L. Krasnov.

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