Ординатура / Офтальмология / Английские материалы / Primary Care Ophthalmology_Palay, Krachmer_2005
.pdf
Non–Vision-Threatening Causes of Red Eye |
65 |
|
|
FIGURE 3–56 Marked conjunctival vascular dilatation in a patient with a carotid artery–cavernous sinus fistula.
FIGURE 3–57 Dilated palpebral and bulbar conjunctival vessels in a patient with polycythemia vera.
from long periods of reading, driving, or using the computer, which frequently are accompanied by decreased blinking. In these situations, the eyes often are dry and can be helped with artificial tears. Some patients may find relief with the use of a cool or warm damp washcloth placed over the eyes.
Uncommon Conditions
Two very uncommon red eye–producing conditions, both characterized by very dilated conjunctival vessels but no discharge, are carotid artery–cavernous sinus fistula (Fig. 3–56) and polycythemia vera (Fig. 3–57). These conditions are mentioned to remind the examiner to keep an open mind concerning the etiology of the red eye.
CHAPTER 4
Eyelid Abnormalities
TED H. WOJNO
Related Anatomy
In adults, the upper lid usually rests at a point between the upper limbus (corneoscleral junction) and upper pupillary border. The lower lid margin usually rests along the inferior limbus. A small amount of scleral “show” (visibility of the sclera between lid and limbus) is not abnormal in the lower lid but is abnormal in the upper lid. In most people, the upper lid has a distinct crease where fibers from the levator muscle insert; this is covered by a small fold of skin. A lower lid crease sometimes is present and is less well defined than that in the upper lid. The upper and the lower lids join at the medial and the lateral canthi (Fig. 4–1).
The tarsal plates are composed of dense, collagenous tissue that forms the “skeleton” of the lids. Vertically oriented meibomian oil glands within the tarsi have orifices visible just posterior to the lashes (Fig. 4–2). The tarsal plates are attached to the orbital rims by the medial and lateral canthal tendons.
Elevation of the upper lid is primarily the work of the levator muscle (innervated by the third cranial nerve) and is assisted by Müller’s muscle (through sympathetic innervation). Third nerve palsy results in moderate drooping of the lid (at least 3 mm lower than usual), a condition known as ptosis, whereas sympathetic palsy results in mild lid drooping (1 to 2 mm lower than usual).
The orbicularis muscle, innervated by the seventh cranial nerve, is responsible for involuntary blinking and forceful lid closure. The lids are separated from the orbit by the orbital septum, a fibrous membrane that functions to prevent the spread of superficial infections into the orbit. Thinning of the septum with age allows the orbital fat to prolapse anteriorly, causing characteristic bulges, or “bags,” in the lids.
Ectropion
Symptoms
•Irritation, burning, and foreign body sensation occur.
•Tearing results from punctal malposition.
67
68 CHAPTER 4 • Eyelid Abnormalities
Tarsal portion of lid |
|
Orbital portion of lid |
Caruncle |
|
Superior lid |
Medial canthus |
|
crease |
|
|
|
Tarsal portion of lid |
|
Lateral canthus |
|
|
|
Inferior lid |
|
|
crease |
|
Orbital portion of lid |
FIGURE 4–1 Eyelid structures.
Signs
•An out-turned lower lid margin is evident, often with a visible space between the globe and the lid (Fig. 4–3).
Etiology
•Involutional: The disorder is caused by lower lid laxity, which occurs with aging.
•Cicatricial: The disorder is caused by a scar on the lower lid skin.
•Paralytic: The disorder is caused by a seventh nerve palsy.
•Mechanical: The disorder is caused by a mass on the lower lid or cheek.
•Congenital: The disorder rarely has a congenital origin.
Treatment
• Surgery is performed to correct any causative abnormality.
Entropion
Symptoms
•Irritation, burning, and foreign body sensation occur.
•Tearing results from lashes abrading the globe.
Signs
• An in-turned lower lid margin is evident (Fig. 4–4).
Etiology
•Involutional: The disorder is caused by lower lid laxity, which occurs with aging.
•Cicatricial: The disorder is caused by a scar on the conjunctival surface such as from a chemical burn.
•Congenital: The disorder rarely has a congenital origin.
Entropion 69
Levator muscle
Cranial nerve III
Orbicularis muscle
Cranial nerve VII
Muller's¨ muscle sympathetic innervation
Levator aponeurosis
Meibomian gland orifice
Meibomian gland in tarsal plate
Muller's¨ muscle
Orbital fat
FIGURE 4–2 Side view of eyelid anatomy.
FIGURE 4–3 Involutional ectropion.
70 CHAPTER 4 • Eyelid Abnormalities
FIGURE 4–4 Involutional entropion.
Treatment
• Surgery is performed to correct any causative abnormality.
Trichiasis
Symptoms
•Irritation, burning, and foreign body sensation are reported by the patient.
•Tearing results from lashes abrading the globe.
Signs
• Lashes on a normally positioned lid margin are posteriorly misdirected (Fig. 4–5).
Etiology
•Spontaneous: The disorder usually affects an isolated lash or two and often occurs at the site of a previous stye.
•Previous injury: An inflammatory process of the conjunctiva results from injuries such as a chemical burn or a disease such as ocular cicatricial pemphigoid.
Associated Diseases
• The disorder may coexist with cicatricial entropion.
Treatment
•Isolated lashes are removed with forceps.
•Extensive lash abnormalities are corrected with surgery.
Lagophthalmos
Symptoms
•Irritation, burning, and foreign body sensation are reported by the patient.
•Tearing is caused by failure of the “lacrimal pump.”
Lagophthalmos 71
FIGURE 4–5 Trichiasis. The lashes are rubbing on the cornea.
FIGURE 4–6 Lagophthalmos of the left eye due to seventh nerve palsy.
Signs
• The patient cannot completely close the eye (Fig. 4–6).
Etiology
Possible causes include the following:
•Severe lower lid laxity
•Seventh nerve palsy
•Proptosis
•Overcorrected ptosis repair or blepharoplasty
•Scarring changes in upper or lower lid
Treatment
•The following applies to seventh nerve palsy:
Mild: Artificial tears or tear ointments are used. The eye is taped shut at night.
Moderate to severe: Lid margins are sutured together (tarsorrhaphy).
Permanent: A gold weight is surgically inserted into the upper lid.
•For other causes, the primary problem is treated.
72 CHAPTER 4 • Eyelid Abnormalities
FIGURE 4–7 Ptosis of the right upper lid.
Ptosis
Symptoms
•Obstruction of the superior visual field occurs.
•Reading is difficult, with acquired ptosis usually worse in downgaze.
•The patient is concerned about the cosmetic appearance of the lid.
•If the ptosis is congenital or acquired in early childhood, amblyopia often is present.
Signs
• The upper lid margin is in an abnormally low position (Fig. 4–7).
Etiology
•Congenital: The disorder usually results from a malformed levator muscle.
•Acquired: A thinning or detachment of the levator aponeurosis is present.
•Horner syndrome: The disorder involves 1 to 2 mm of ptosis with a small pupil on the same side (see Chapter 12).
•Third nerve palsy: With ophthalmoplegia, more than 3 mm of ptosis is present (see Chapter 12).
•Myasthenia gravis: Ptosis varies in severity and may worsen with sustained upgaze (see Chapter 12).
Treatment
•For congenital or acquired lesions, surgery is performed to tighten the levator aponeurosis or resect the levator muscle.
•For other causes, the primary problem is treated.
Floppy Eyelid Syndrome
Symptoms
•Irritation, burning, foreign body sensation, and discharge are reported by the patient.
Seborrheic Keratosis |
73 |
|
|
FIGURE 4–8 Floppy eyelid syndrome demonstrating ease with which upper lid is everted.
Signs
•The disorder is usually unilateral or asymmetrical.
•Chronic conjunctivitis that is nonresponsive to topical antibiotics is present.
•A giant papillary reaction (papillae greater than 1 mm in size) of the tarsal conjunctiva occurs, giving the surface a red cobblestone or velvety appearance.
•A characteristic finding is the ability to evert the patient’s upper lid by simply pulling upward from the lateral brow area (Fig. 4–8).
Etiology
•An abnormal laxity of the lateral canthal tendon and tarsal plate is present in affected persons.
•The upper lid everts during sleep and rubs against the pillow, leading to severe irritation of the conjunctiva and mucus secretion.
Treatment
•A Fox shield (plastic or metal shield usually worn after cataract surgery) is taped over the eye at night to prevent the lid from rubbing on the pillow.
•Surgery is necessary to tighten the upper and lower lids horizontally; the procedure may need to be repeated after several years.
Seborrheic Keratosis
Symptoms
•Patients usually are symptom free.
•Occasional itchiness is reported.
Signs
•The lesion usually is well demarcated with variable pigmentation, a “stuck-on” appearance, and a cerebriform surface (Fig. 4–9).
•A lobulated papillary or pedunculated frond sometimes is present at the lid margin.
74 CHAPTER 4 • Eyelid Abnormalities
FIGURE 4–9 Seborrheic keratosis.
Differential Diagnosis
Considerations in the differential diagnosis include the following:
•Nevus
•Basal cell carcinoma
•Melanoma
Treatment
•Seborrheic keratoses are benign lesions, usually requiring no treatment.
•A superficial shave biopsy or an excision can be performed if lesions are cosmetically undesirable.
Actinic Keratosis
Symptoms
•Patients usually are symptom free.
•Occasional itchiness is reported.
Signs
•The disorder varies in morphologic appearance, ranging from a flat, scaly lesion to a papilloma to a cutaneous horn (Fig. 4–10).
Etiology
• The disorder results from overexposure to actinic radiation.
Differential Diagnosis
Considerations in the differential diagnosis include the following:
•Squamous cell carcinoma
•Verruca
•Seborrheic keratosis
Xanthelasma 75
FIGURE 4–10 Actinic keratosis.
Associated Factors and Diseases
•The disorder is more common in fair-skinned persons.
•A lesion may develop into squamous cell carcinoma.
Treatment
The three treatment options are as follows:
•Surgical excision is performed.
•Patients undergo cryotherapy.
•Topical 5-fluorouracil (e.g., Efudex) is prescribed.
Xanthelasma
Symptoms
•Patients usually are symptom free.
•The disorder is a cosmetic deformity.
Signs
•A bilateral, plaquelike yellow lesion usually is present (Fig. 4–11).
•The lesion is found in the medial upper and lower lids.
Etiology
• The origin usually is idiopathic.
Associated Factors and Diseases
•The disorder affects middle-aged to elderly persons, predominantly women.
•The disorder occasionally is associated with hyperlipidemia or diabetes.
Treatment
•Surgical excision of the involved skin is performed.
•A skin graft often is necessary following removal of a large lesion.