Ординатура / Офтальмология / Английские материалы / Primary Care Ophthalmology_Palay, Krachmer_2005
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86 CHAPTER 4 • Eyelid Abnormalities
FIGURE 4–20 Contact dermatitis from tape used to secure an eye patch.
Etiology
• Pollen, dust, chemicals, and cosmetics are causative agents.
Differential Diagnosis
Considerations in the differential diagnosis include the following:
•Atopic dermatitis
•Seborrheic dermatitis
•Psoriasis
•Preseptal cellulitis
Workup
•A thorough history of the exposure is obtained.
•The possibility of infection is excluded.
•Patch testing may be necessary.
Treatment
•Patients are advised to avoid contact with the suspected cause.
•A topical corticosteroid such as fluorometholone 0.1% ophthalmic ointment is applied to the lids. Prolonged use of such agents can be associated with glaucoma and cataracts.
Essential Blepharospasm
Symptoms
•Irritation, burning, and foreign body sensation are reported by the patient.
•An inability to keep the eyes open, frequent blinking, and photophobia are other complaints.
Signs
• Obvious, frequent blinking, and an inability to open the eyes are evident (Fig. 4–21).
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FIGURE 4–21 The patient had essential blepharospasm.
Etiology
• The disorder probably results from an abnormality of the basal ganglia or midbrain.
Differential Diagnosis
•Any secondary cause of blepharospasm such as iritis, corneal foreign body, or keratitis is identified.
Associated Factors and Diseases
•The disorder often is associated with other dystonic movements of the face and neck (Meige syndrome).
•The disorder sometimes is associated with peripheral dystonias of the legs, arms, and back and Parkinson’s disease.
•A family history of the disorder occasionally is reported.
Treatment
•Botox (botulinum toxin) injections into the eyelids and other affected facial muscles are administered. Botox produces a positive response in approximately 90% of patients.
•Oral medication with clonazepam (Klonopin) can be tried if Botox is ineffective or not maximally effective.
•Surgery (orbicularis myectomy or differential section of the seventh cranial nerve) is performed if administration of Botox and oral medication fail.
Follow-up
• Botox injections usually need to be repeated every 2 to 3 months.
CHAPTER 5
Conjunctival
Abnormalities
DAVID A. PALAY
Related Anatomy
The conjunctiva is a thin, transparent mucous membrane that lines the inner surface of the lids and outer surface of the eye. The portion of the conjunctiva on the eye is the bulbar conjunctiva, and the portion of the conjunctiva on the lid is the palpebral conjunctiva. The point of transition between these two zones is the fornix. An inferior and a superior fornix normally are present (Fig. 5–1). Glands in the conjunctiva produce the components of the tear film; a healthy conjunctiva is therefore essential for maintaining a healthy corneal surface. The conjunctiva also serves as a barrier against infection. Medially, the two important conjunctival structures are the plica semilunaris and the caruncle (Fig. 5–2).
Viral Conjunctivitis
Symptoms
•The onset of the disorder is acute.
•Redness, watering, soreness, and general discomfort are typical complaints.
•The second eye usually is involved 3 to 7 days after the first, and the symptoms are less severe in most cases.
Signs
•Diffuse injection of the conjunctiva with a watery discharge is present (Fig. 5–3).
•In severe cases, erythema and edema often are found in the lids (Fig. 5–4).
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90 CHAPTER 5 • Conjunctival Abnormalities
Fornix
Bulbar conjunctiva
Palpebral conjunctiva
FIGURE 5–1 The region of the conjunctiva.
Palpebral conjunctiva
Bulbar conjunctiva
Fornix
FIGURE 5–2 Conjunctiva, normal anatomy. The medial fold in the conjunctiva is the plica semilunaris (1). The caruncle
(2) is an elevated mass that has features of both skin and conjunctiva.
2 1
FIGURE 5–3 Diffuse injection of the conjunctiva with a watery discharge is evident in this case of viral conjunctivitis.
Viral Conjunctivitis |
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FIGURE 5–4 In this severe case of viral conjunctivitis, erythema and swelling of the lids and periocular skin are noted in addition to the diffuse injection of the conjunctiva.
FIGURE 5–5 Small, elevated, cystic-appearing lesions termed follicles commonly occur on the palpebral conjunctiva in viral conjunctivitis.
•A follicular response in the conjunctiva is evident in most cases (Fig. 5–5).
•Preauricular adenopathy is common; patients may report tenderness in this region. Bacterial conjunctivitis is almost never associated with preauricular adenopathy, which can be a differentiating feature.
•Subepithelial infiltrates can develop in the cornea 2 to 3 weeks after the acute infection (Fig. 5–6). They result from the body’s immune response to viral antigens and can cause decreased vision and photosensitivity.
Etiology
• Adenovirus infection (epidemic keratoconjunctivitis) usually is the cause.
Treatment
•The disease is self-limiting.
•Symptoms are treated, usually with cold compresses, artificial tears, and a vaso- constrictor-antihistamine combination (e.g., naphazoline plus pheniramine maleate [Naphcon-A], naphazoline plus antazoline phosphate [Vasocon-A]) four times a day if the itching is severe.
•Patients are counseled about the highly contagious nature of this viral infection. Infected persons involved in patient care should be excused from work until the acute signs and symptoms have resolved (usually in 5 to 14 days).
92 CHAPTER 5 • Conjunctival Abnormalities
FIGURE 5–6 Subepithelial infiltrates may be noted in the cornea 2 to 3 weeks after the acute viral infection.
FIGURE 5–7 Diffuse injection of the conjunctiva with a thick, purulent discharge is evident in this case of bacterial conjunctivitis.
Bacterial Conjunctivitis
Symptoms
•Redness, irritation, and adhesion of the lids (especially in the morning) are typical complaints.
Signs
•A mucopurulent exudate is found in the fornix and on the lid margin (Figs. 5–7 and 5–8).
•In cases of diffuse conjunctivitis, erythema and edema of the lids sometimes are observed.
•Neisseria gonorrhoeae and Neisseria meningitidis cause a “hyperacute” conjunctivitis characterized by an exuberant mucopurulent discharge (Fig. 5–9). Because the organism can rapidly invade the cornea, causing tissue destruction and ocular perforation, infection with Neisseria species results in a potentially serious form of conjunctivitis (Fig. 5–10).
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FIGURE 5–8 In this case of bacterial conjunctivitis, the purulent material has dried, creating a thick crust of material on the lid and lid margin.
FIGURE 5–9 Bacterial conjunctivitis resulting from infection with Neisseria gonorrhoeae. A thick, mucopurulent discharge can be seen on the conjunctiva and lids.
FIGURE 5–10 In this case of bacterial conjunctivitis resulting from infection with Neisseria gonorrhoeae, a central corneal perforation is evident, and retina plugs the perforation site.
94 CHAPTER 5 • Conjunctival Abnormalities
Etiology
•Any of several bacterial species can cause conjunctivitis; Staphylococcus aureus,
Haemophilus species, Streptococcus pneumoniae, and Moraxella species are the most common agents. N. gonorrhoeae and N. meningitidis are rarely the cause.
Workup
•Gram stain and conjunctival culture are performed in any cases suggestive of conjunctivitis caused by Neisseria species.
•Most cases do not require extensive workup, because broad-spectrum antibiotics eradicate the infection.
Treatment
•A broad-spectrum antibiotic, such as a fluoroquinolone (e.g., ciprofloxacin [Ciloxan], ofloxacin [Ocuflox], moxifloxacin [Vigamox], gatifloxacin [Zymar]), or polymyxin B/trimethoprim (Polytrim), or sulfacetamide drops, is administered four to six times a day.
•Drops are preferred over ointments because the latter can cause blurring of the patient’s vision.
•For conjunctivitis caused by Neisseria species, the following apply:
Urgent referral to an ophthalmologist is necessary.
The eyes are irrigated with saline solution and the lids are cleansed four to six times a day.
Topical antibiotics (e.g., bacitracin, erythromycin ointment) are applied four to six times a day.
A single dose (1 g) of ceftriaxone (Rocephin) is injected intramuscularly in adults. In patients with severe penicillin allergy, medication with an oral fluoroquinolone (e.g., ciprofloxacin) for 7 days may be effective.
A twice-a-day oral dose of doxycycline (100 mg) is administered for 3 weeks to treat a concomitant chlamydial infection that may be present. Tetracycline and doxycycline are contraindicated in children, pregnant women, and breastfeeding mothers.
Sexual partners are counseled and treated.
Adult Chlamydial Conjunctivitis
Symptoms
•The onset of the disorder is acute or subacute.
•Redness, foreign body sensation, tearing, and photosensitivity are typical complaints.
Signs
• The conjunctivitis is more often unilateral than bilateral.
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FIGURE 5–11 Diffuse injection of the conjunctiva is evident in this case of adult chlamydial conjunctivitis.
FIGURE 5–12 The inferior palpebral conjunctiva demonstrates multiple cystic-appearing lesions (follicles) in adult chlamydial conjunctivitis.
Etiology
•Ocular inoculation usually results from chlamydial infection of the genitalia.
•Diffuse injection of the conjunctiva with a scant mucopurulent discharge is present (Fig. 5–11).
•A follicular response in the conjunctiva usually is present (Fig. 5–12).
•Preauricular adenopathy is possible.
Workup
•Giemsa stain of a conjunctival scraping may show basophilic inclusion bodies (Fig. 5–13).
•Direct fluorescent antibody staining of conjunctival scrapings can be useful; however, a high incidence of false-negative results has been reported.
Treatment
•Medication entails oral tetracycline (250 mg) four times a day for 3 weeks or oral doxycycline (100 mg) twice a day for 3 weeks. Tetracycline and doxycycline are contraindicated in children, pregnant women, and breastfeeding mothers. If tetracyclines are contraindicated or not tolerated, oral erythromycin (250 mg) four times a day for 3 weeks is an effective alternative.
•Topical treatment consists of application of erythromycin ointment two to four times a day for 3 weeks.
•Sexual partners also are given appropriate treatment.
96 CHAPTER 5 • Conjunctival Abnormalities
FIGURE 5–13 An epithelial cell from a conjunctival scraping obtained from a patient with adult chlamydial conjunctivitis shows basophilic inclusion bodies (1), the cell cytoplasm (2), and the cell nucleus (3).
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Allergic Conjunctivitis
Symptoms
• The most predominant symptom is intense itching.
Signs
•The conjunctivitis is almost always bilateral.
•Mild conjunctival injection is present.
•A stringy mucoid discharge is evident.
Associated Factors and Diseases
•The disorder is usually seasonal, often occurring in persons with a history of atopic disease.
•Some airborne allergies (e.g., animal dander, dust, plant pollens, ragweed, mold spores) can incite a type I hypersensitivity reaction with acute swelling of the conjunctiva (chemosis) (Fig. 5–14).
Treatment
•Systemic allergy evaluation is performed with consideration of desensitization treatment and removal of allergens from the patient’s environment.
•Systemic antihistamines are administered.
•Several topical preparations may be useful:
Topical vasoconstrictor-antihistamine combinations (e.g., naphazoline plus pheniramine maleate [Naphcon-A], naphazoline plus antazoline phosphate