Eyelids Anatomy and Diseases - PDF

eyelids ‫ﺳوزان ﻗﺣطﺎن‬.‫د‬ Applied anatomy Eyelids are two movable folds of tissue situated above and below the front of each eye.There are short curved hair; the eyelashes, situated on their free edges. The layers of tissue which form eyelids ar...

eyelids ‫ﺳوزان ﻗﺣطﺎن‬.‫د‬ Applied anatomy Eyelids are two movable folds of tissue situated above and below the front of each eye.There are short curved hair; the eyelashes, situated on their free edges. The layers of tissue which form eyelids are: A thin covering of skin A thin sheet of areolar tissue Three muscles— Orbicularis oculi, levator palpebrae superioris and Muller muscle. A thin sheet of dense connective; the tarsal plate, larger in the upper lid than the lower lid. It supports the other structures. A lining of palpebral conjunctiva. The lid margin It is divided in to rounded anterior and sharp posterior borders by the grey line.The eyelashes originate anterior to grey line and ducts of the meibomian glands are located posterior to the grey line. Grey line is an impotantsurgical land mark in operations where the lid is split as it indicates the position of the loose fibrous tissue between the tarsus and the orbicularis. Meibomian glands Modified sebaceous glands about 20-30 in number embeded in the tarsal plate, their ducts open at the lid magin. Zeis glands Modified sebaceous glands attached to the hair follicle. Moll glands Modified sweat glands open in to the hair follicle Orbital septum It is a t hin membrane of conneclive tissue attached ce ntrally to the tarsal plates and periphe rally to periosteum of the orbital margin. It is perforated by nerve , vessels and leva tor p alpebrae supe rioris (LPS) muscl e, whi1ch ente r the lids from the orbit. Tarsal plate There a re two plates of dense connective tissue, one for each lid, which g ive shape and firmness to the lids. Levator palpebrae superioris muscle (LPS) is present in upper eyelid only. lt arises from the apex of the orbit and is inserted by three parts on th e skin oflid, anterior s urface of the tarsal plate and conjunctiva of superior fornix. It raises the upper lid. It is s upplied by a branch of oculomotor nerve. In the substance of the tarsal plates lie m ei bomian glands in parallel rows. Muller muscle whi ch lies deep to the orbital septum in both the lids. In the upper lid., it arises from the fibres ofLPS muscle and in the lower lid from prolongation of the infe rior rectus muscle; and is inserted on the peripheral margins of the tarsal plate. It is supplied by sympathetic fibres. Orbicularis oculi Orbicularis muscle whic h forms an oval sheet across the eyelid s. It comprises three portions: Orbital part en circles the orbital margin. Preseptal part lies anterior to orbital septum and is loosely attached to it. It is supplied by facial nerve(IV) Diseases of the lids 1-Inflammation Blepharitis Stye Chalazion 2-Abnormalities in the position of the lid Trichiasis Ectropion Entropion Ptosis 3-Tumors Basal cell carcinoma Squamous cell carcinoma Sebaceous glands carcinoma Melanoma Blepharitis It is a subacute or chronic inflammation of the lid margins. It is an extremely common disease which can be divided into following clinical types: Bacterial blepharitis, Seborrhoeic blepharitis, Posterior blepharitis or meibomitis Bacterial blepharitis :a chronic infection of the anterior part of the lid margin. It is a common cause of ocular discomfort and irritation. The disorder usually starts in childhood and may continue throughout life. Most commonly caused by staph. Aureus. Seborrhoeic blepharitis: It is usually associated with seborrhoea of scalp (dandruff). In it, glands of Zeis secrete abnormal excessive neutral lipids which are split by Corynebacterium acne into irritating free fatty acids. Posterior Blepharitis (Meibomitis) Meibomitis, i.e. inflammation of Meibomian glands is a commonly occurring meibomian gland dysfunction, seen more commonly in middle-aged persons, especially those with acne rosacea and/or seborrhoeic dermatitis Symptoms include chronic irritation, burning, itching, grittiness, mild lacrimation with remissions and exacerbations intermittently. Symptoms are characteristically worse in the morning. Signs : Yellow crusts are seen at the root of cilia which glue them together. Red, thickened lid margins are seen with dilated blood vessels. Hyperaemia and telangiectasia of posterior lid margin around the orifices of meibomian glands can be seen frequently. Oily and foamy tear film with accumulation of froth on the Lid margins or inner canthus. Openings of meibomian glands become prominent with thick secretions Treatment 1. Lid hygiene is essential at least twice daily and should include: Warm compresses for 5-10 minutes to soften the crusts. Crust removal and Lid margin cleaning with the help of cotton buds dipped in the dilute baby shampoo. Avoid rubbing of the eyes or fingering of the lids. 2. Antibiotics should be used as below: Eye ointment should be applied at the Lid margin, immediately after removal of the crusts. Antibiotic eye drops should be used 3-4 times a day.  Oral antibiotics such as erythromycin or doxycycline may be useful in unresponsive patients and those complicated by external hordeola and abscess of lash follicle. 3. Topical steroids (low potency) such as fluoro - metholone may be required. 4. Ocular lubricants, i.e. artificial teardrops, are required for associated tear film instability and dry eye. 5. Systemic tetracyclines, e.g. doxycycline for 6-12 weeks, remain the mainstay of treatment of posterior blepharitis. EXTERNAL HORDEOLUM (STYE) It is a n acute suppurative inflammation of lash follicle and its associated glands of Zeis or Moll. the causative microorganism is staph.aureus. Age. It is more common in children and young adults ( though no age is bar) and in patients with eye strain due to muscle imbalance or refractive errors. Habitual rubbing of the eyes or fingering of the lids and nose, chronic blepharitis and diabetes mellitus are usually associated with recurrent styes. Symptoms include acute pain associated with swelling of lid, mild watering and photophobia. Signs It is characterized by localized, firm, red, tender swelling at the lid margin associated with marked oedema Treatment Hot compresses 2-3 times a day are very useful especially in cellulitis stage. Evacuation of the pus should be done by epilating the involved lash, when the pus point is formed. Antibiotic eye drops (3-4 times a day) and eye ointment (at bed time) should be applied to control the infection. CHALAZION Chalazion, also called a tarsal or meibomian cyst, is a chronic non-infective (non- suppurative) lipogranulomatous inflammation of the meibomian gland. This is the commonest of all lid lumps. It is caused by blockage of the duct of the Meibomian gland which leads to retention of secretions(sebum) in the gland, causing its enlargement. The pent-up and extravasated secretions (fatty in narure) act like an irrirant and excite non- infective lipogranulomatous inflammation of the blocked meibomian glands and surrounding tissue. Symptoms Painless swelling in the eyelid, gradually increasing in size is the main presenting symptom. Blurred vision may occur occasionally due to induced astigmatism by a very large chalazion pressing on the cornea. Secondary infection can occur by staph.aureus. Signs Nodule is noted slightly away from the lid margin which is firm to hard and non- tender on palpation. Upper lid is involved more commonly than the lower lid Frequently multiple chalazia may be seen. Reddish purple area, where the chalazion usually points, is seen on the palpebral conjunctiva after eversion of the lid. Treatment 1. Conservative treatment. In a small, soft and recent chalazion, self-resolution may be helped by conservative treatment in the form of hot fomentation, topical antibiotic eye drops and oral anti-inflammatory drugs. 2. Intralesional injection of long-acting steroid (triamcinolone) is reported to cause resolution in about 50% cases. 3. lncision and curettage is the conventional and effective treatment for chalazion. 4. Oral tetracycline should be given as prophylaxis in recurrent chalazia. Abnormalities in lid positon Ectropion It means outward rolling of the eyelid margin. It can be classified into: 1-Senile (age related) ectropion affects lower lid of elderly patients caused by lid laxity, it is the commonest type. 2-Cicatricial ectropion is caused by scarring or contracture of the skin and underlying tissues, which pulls the eyelid away from the globe. 3-Paralytic ectropion is caused by ipsilateral facial nerve palsy. 4-Mechanical ectropion is caused by tumors on or near the lid margin that mechanically evert the lid. Symptoms: The most common symptom is epiphora i.e constant watering of the eyes. Signs: 1.Conjunctiva becomes dry in appearance and thickened in texture. 2.Chronic conjunctivitis may be present due to exposure of the conjunctiva and cornea. 3.Corneal ulcer may occur (exposure keratitis). Treatment: Temporary measures : taping shut of the lids, apply lubricant gel during sleep can be beneficial in mild cases. Definitive treatment: surgery Entropion It is in word rolling of the eyelid margin, it can be classified into: 1-Involutional (age-related) entropion affects mainly the lower lid. 2-Cicatricial entropion due to Scarring of the palpebral conjunctiva can rotate the upper or lower lid margin towards the globe. Causes include cicatrizing conjunctivitis, trachoma, trauma and chemical injuries. 3-Congenital; the least common form. Clinically The constant rubbing of the lashes on the cornea (pseudotrichiasi) may cause irritation, foreign body sensation, red eye, and in long standing cases corneal punctate epithelial erosions and, in severe cases corneal ulceration. Treatment In mild cases the lid is pulled away from the lid margin by adhesive plaster. The definitive treatment is surgical. Trichiasis It is a condition where the eyelashes are misdirected backwards against the cornea. A few lashes are or whole lid can be involved. It can occur in old age , or as a result of scarring of the palpebral conjunctiva as in burns , cicatrizing conjunctivitis and trachoma. Clinically: same as entropion. Treatment: 1.Isolated lashes i.Epilation or removal of misdirected eyelashes and repeated every weeks. ii.Electrolysis- is preferable as it causes destruction of the hair follicle , it may be repeated every months. 2.Whole lid margin involvement – treated surgically.