286 OPHTHALMOLOGY SECRETS IN COLOR
KEY POINTS: THYROID EYE DISEASE
1. Suspect the diagnosis of TED in nonspecific ocular irritation even without a systemic thyroid imbalance.
2. Eyelid retraction is often the earliest clinical sign of TED. 3. Monitor visual function closely in progressive TED.
4. Get patients who are smokers to stop smoking.
5. TED patients will take extra time during an office visit.
29.What are the alternatives to muscle surgery?
The use of prisms in glasses works for patients with double vision and relatively small deviations. Larger deviations or patterns of diplopia in which the deviation changes with small changes in the direction of gaze are poor candidates for prisms. It is also important that the motility is stable before prisms are prescribed. Temporary Fresnel prisms may be helpful during periods of instability.
30.What type of muscle surgery is required?
Recession of muscles, usually on an adjustable suture, is needed. Because the muscles are tight and scarred, resection is not done. The inferior and medial rectus muscles are the most common targets of surgery. Surgery can be done under local or general anesthesia with adjustment of the sutures later in the day or on the following day.
31.Does eye muscle surgery affect the eyelids?
Recession of the tight inferior rectus muscle often improves upper eyelid retraction. The superior rectus muscle has to work against the tight inferior rectus; thus the associated levator muscle is overactive, causing eyelid retraction. When the inferior muscle is recessed, the overactivity ends and often the upper eyelid retraction is less. Large recessions of the inferior rectus muscle may worsen inferior eyelid retraction.
32.What kind of eyelid surgery is done?
Eyelid retraction is the main eyelid problem in patients with TED. In patients undergoing orbital decompression, the eye is lowered, often improving the lower eyelid retraction. For mild eyelid retraction, recession of the eyelid retractors (upper or lower) is adequate. For more severe retraction, spacers are needed, such as hard palate or acellular dermis in the lower eyelids. Patients also may require a blepharoplasty and/or brow lift to deal with the excessive skin that results from stretching caused by chronic swelling. This goal may be met at the time of eyelid repositioning or at a later date.
33.How many surgeries do patients with thyroid eye disease require?
Most patients with TED do not require surgery. Patients who do need surgery may need from 1 to as many as 8 to 10 operations. Patients with severe disease may require many operations over 2 to 3 years of reconstruction.
Bibliography
Bartalena L, Marcocci C, Bogazzi F, et al.: Relation between therapy for hyperthyroidism and the course of Graves’ ophthalmopathy, N Engl J Med 1338:73–78, 1998.
Bartley GB, Fatourechi V, Kadrmas EF: The chronology of Graves’ ophthalmopathy in an incidence cohort, Am J Ophthalmol 121:426–434, 1996.
Gorman CA, Garrity JA, Fatourechi V: A prospective, randomized, double-blind, placebo-controlled study of orbital radiotherapy for Graves’ ophthalmopathy, Ophthalmology 108:1523–1534, 2001.
Holds JB, Buchanan AG: Graves’ orbitopathy. Focal points: clinical modules for ophthalmologists, San Francisco, 2010, American Academy of Ophthalmology. module 11.
Mourits MP, van Kempen-Harteveld MI, Garcia MB, Koppeschaar HP, et al.: Radiotherapy for Graves’ orbitopathy: randomized placebo-controlled study, Lancet 355(9412):1505–1509.
Rootman J, Stewart B, Goldberg RA: Orbital surgery: a conceptual approach, Philadelphia, 1996, Lippincott-Raven.
ORBITAL INFLAMMATORY DISEASES
Nicole A. Langelier, Usiwoma Abugo, and Roberta E. Gausas
1.What is inflammation?
The concept of inflammation is ancient and was used to describe a combination of rubor (redness), dolor (pain), tumor (swelling), calor (heat), and functio laesa (loss of function). We now recognize inflammation as a tissue response governed by multiple cellular processes.
2.How does inflammation affect the orbit?
Inflammation is the most common problem that affects the adult orbit, leading to a spectrum of clinical presentations with variable onset and variable orbital tissues affected, causing mass effect, inflammation, and/or infiltration resulting in variable deficits in function or vision.1
3.What are the best terms to describe orbital inflammation?
For purposes of better understanding and better management, orbital inflammation should be classified based on pathology, anatomic location, and/or associated systemic disease as either specific or nonspecific in nature.
4.What is specific orbital inflammation?
The diagnosis of specific orbital inflammation is based on the identification of a specific etiology causing the disorder, such as a specific pathogen (infection, as in orbital cellulitis), specific histopathology (granulomatous disease, as in sarcoidosis), or specific local and/or systemic constellation of findings that define a distinct entity (vasculitis, as in granulomatosis with polyangiitis) (Box 36-1).2
5.How is nonspecific orbital inflammation different?
Orbital inflammation that has no identifiable cause is considered nonspecific. It is a diagnosis of exclusion.
6.What is orbital pseudotumor?
“Nonspecific orbital inflammation” and “idiopathic orbital inflammatory syndrome” are more accurate terms that replace orbital pseudotumor.
7.What, then, is the etiology of nonspecific orbital inflammation?
The exact etiology is unknown but it is generally believed to be an immune-mediated process, possibly related to previous bacterial or viral infection, previous trauma, or other autoimmune conditions, such as Crohn’s disease, rheumatoid arthritis, and systemic lupus erythematosis.3
8.Describe a typical clinical presentation of nonspecific orbital inflammation.
Anterior orbital nonspecific orbital inflammation (NSOI) commonly presents as painful periorbital swelling and erythema, S-shaped eyelid deformity, and chemosis that may be unilateral or bilateral. Onset is typically acute (hours to days) or subacute (days to weeks) but can also be insidious or chronic (weeks to months). The symptoms and physical findings will vary based on the degree and anatomic location of the inflammation. Disease affecting the posterior orbit may present with proptosis and motility disturbances, and disease affecting the orbital apex may present with functional deficits and/ or vision loss.
9.Is the symptom of pain necessary to make the diagnosis?
Although pain or discomfort is a typical symptom, absence of pain may occur less commonly.4
10.How is nonspecific orbital inflammation in children different?
In the pediatric population, bilateral manifestation is much more common, as well as concurrent uveitis, elevated erythrocyte sedimentation rate, and eosinophilia. When present, uveitis in particular appears to portend a poor outcome in children. Overall, NSOI in children is rare and cases should be monitored closely for future development of autoimmune disease.5-7
288 OPHTHALMOLOGY SECRETS IN COLOR
BOX 36-1. Differential Diagnosis of Orbital
Inflammation
Nonspecific Orbital Inflammation (NSOI)
Diagnosis after exclusion of specific inflammations
Specific Orbital Inflammation
Thyroid-associated orbitopathy
Infection/infestation
Bacterial
Contiguous spread from sinusitis
Retained orbital foreign body
Fungal
Rhino-orbital mucormycosis
Aspergillosis
Endogenous spread from septic emboli
Parasitic
Echinococcosis
Cysticercosis
Tuberculosis and syphilis
Vasculitis
Granulomatosis with polyangiitis
Polyarteritis nodosa
Hypersensitivity angiitis
Orbital vasculitis secondary to systemic lupus erythematosus
Giant cell arteritis
Granulomatous inflammation
Sarcoidosis/sarcoidal reactions
Xanthogranulomatous disorders of orbit
Foreign-body granuloma
Erdheim-Chester disease
Sjögren’s syndrome
IgG4-related disease of the orbit
Sclerosing inflammation of the orbit
Idiopathic granulomatous inflammation
Nonspecific Orbital Inflammation (NSOI)
Noninflammatory Diseases of the Orbit that
Mimic Inflammation
Vascular disorders
Dural–cavernous sinus arteriovenous fistula
Neoplasia
Lymphoproliferative disorders
11.Name the five most common anatomic patterns of nonspecific orbital inflammation.
1.Extraocular muscle (myositis)
2.Lacrimal gland (dacryoadenitis)
3.Anterior orbit including scleritis
4.Orbital apex
5.Diffuse
12.How is the diagnosis of nonspecific orbital inflammation made?
Because NSOI is a diagnosis of exclusion, all known specific triggers of inflammation should be ruled out first. Ultimate diagnosis and treatment rely on complete history and detailed clinical examination followed by judicious use of ancillary diagnostic testing. Diagnostic testing includes neuroimaging, laboratory testing, and biopsy when appropriate.
CHAPTER 36 ORBITAL INFLAMMATORY DISEASES 289
13.What is the best imaging technique for nonspecific orbital inflammation?
Orbital computed tomography (CT), gadolinium-enhanced magnetic resonance imaging (MRI), or ultrasound can all provide useful information, but orbital MRI with fat saturation is the imaging study with the highest yield. Subtle edema of the retrobulbar fat is often one of the earliest changes seen in NSOI. The use of diffusion weighted imaging is helpful in differentiating NSOI from lymphoid lesions and orbital cellulitis.8,9
14.What blood tests can be ordered to evaluate nonspecific orbital inflammation?
Complete blood count, electrolytes, erythrocyte sedimentation rate, C-reactive protein, antinuclear antibody, anti-double-stranded DNA, anti-neutrophil cytoplasmic antibody (ANCA), angiotensin- converting enzyme level, rapid plasma reagin, and thyroid function tests.10
15.When should an orbital biopsy be performed?
Although the role of orbital biopsy has previously been an area of controversy, the only way to obtain an accurate and definitive diagnosis of an infiltrative lesion is through pathologic examination. Most orbital surgeons advocate biopsy, except for two clinical scenarios—that of orbital myositis, in which the clinical and radiographic findings are classic, and that of an orbital apex syndrome—in which the risk of biopsy must be weighed against the risk of a missed diagnosis. Empiric steroid treatment may be employed in such cases. However, recurrent or nonresponsive orbital myositis and orbital apex syndrome warrant orbital biopsy.11
16.What is the histopathology of nonspecific orbital inflammation?
In the acute phase, pathology reveals a diffuse polymorphous infiltrate composed of mature lymphocytes, plasma cells, macrophages, eosinophils, and polymorphonuclear leukocytes. In the subacute and chronic phases, an increasing amount of fibrovascular stroma is seen.
17.Name two histological subtypes of orbital inflammation.
A distinct sclerosing form of orbital inflammation exists, which is characterized by dense fibrous replacement. Clinically, the sclerosing subtype typically produces limited inflammatory signs and atypical pain.
Another distinct form displays granulomatous inflammation similar to sarcoidosis but is not associated with systemic sarcoidosis.
18.What is IgG4-related disease?
IgG4-related disease is a systemic fibroinflammatory condition that should be considered in patients with NSOI, particularly in cases with bilateral lacrimal gland involvement. Histology reveals IgG4positive plasma cells and fibrosis, with or without obliterative phlebitis. Serum IgG4 is often elevated. Systemic manifestations of IgG4-related disease include sclerosing pancreatitis, retroperitoneal fibrosis, sclerosing cholangitis, Reidel’s thyroiditis, and interstitial lung disease. IgG4-related orbital inflammation is typically exquisitely and rapidly responsive to steroid treatment.12,13
19.How is nonspecific orbital inflammation treated?
High-dose oral corticosteroids are the mainstay of treatment. The recommended starting dose for prednisone is 1.0 to 1.5 mg/kg/day with a maximum adult dose of 60 to 80 mg/day for 1 to 2 weeks, then tapering off over the course of 6 to 12 weeks. For patients with vision loss or apical involvement, intravenous methylprednisone 1.0 g/day can be administered for 1 to 3 days. The response is usually quick with resolution of pain and proptosis within 24 to 48 hours of onset of the treatment.14
20.What if a patient fails to respond to or is intolerant of steroids?
Alternative therapies include antimetabolites (azathioprine, methotrexate), T-cell inhibitors (cyclosporine), and alkylating agents (cyclophosphamide). Low-dose external beam radiation has also been shown to be effective.
Local injection of betamethasone can also be effective in treating acute idiopathic dacryoadenitis, myositis, and anterior diffuse orbital inflammation.1,15
KEY POINTS: NONSPECIFIC ORBITAL INFLAMMATION
1. Nonspecific orbital inflammation is a diagnosis of exclusion. 2. Onset is usually acute and painful.
3. Inflammation may be unilateral or bilateral.
4. Children often have uveitis and eosinophilia concurrently.
5. Subtle edema of retrobulbar fat is an early finding on imaging.
290 OPHTHALMOLOGY SECRETS IN COLOR
21.What is the most common specific orbital inflammation?
Thyroid-associated orbitopathy.
22.Which extraocular muscle is most likely to be involved in thyroid eye disease?
The inferior rectus is the most likely. An easy-to-remember mnemonic is IMSLO for the order of extraocular muscle involvement: inferior rectus, medial rectus, superior rectus, lateral rectus, and then the obliques.16
23.What infections can occur in the orbit?
The orbit may undergo bacterial (e.g., Staphylococcus, tuberculosis, syphilis), fungal (e.g., rhinoorbital mucormycosis, aspergillosis), parasitic (e.g., echinococcosis, cysticercosis, trichinosis), and viral (e.g., herpetic) infections.
24.Where do orbital infections originate?
•The most common source is contiguous spread of bacteria from the sinuses, often the ethmoid sinus.
•Direct inoculation following trauma or skin infection is another source.
•Infection may spread endogenously from septic emboli.
25.In adults, what pathogens usually cause orbital cellulitis?
Staphylococcus aureus or streptococci are most common. It is important to note that adults need broad-spectrum antibiotics, because multiple organisms tend to be involved, versus children, in whom a single gram-positive organism is usually the culprit.17
26.In a 2-year-old patient, what pathogen might be a likely cause of orbital cellulitis?
Historically, it has been Haemophilus influenza B (Hib), but with the advent of the Hib vaccine most pediatric cases are now the result of gram-positive cocci infection. Vaccination status is an important consideration.
27.How is orbital cellulitis treated?
Medical care consists of the proper use of the appropriate antibiotics. Preseptal cellulitis may be treated with oral antibiotics. Orbital cellulitis requires intravenous administration of antibiotics. Care must be taken to distinguish community-associated methicillin-resistant S. aureus (MRSA) from hospital-acquired MRSA, as the treatment differs and the potential for morbidity and long-term disability is significant.
28.When should surgery be undertaken?
If the response to appropriate antibiotic therapy is poor within 48 to 72 hours or if the CT scan shows the sinuses to be completely opacified, surgical drainage should be considered. Subperiosteal or intraorbital abscess formations are other indications for surgical drainage if there is a decrease in vision, development of an afferent pupillary defect, or failure of proptosis to resolve despite appropriate antibiotic therapy.
KEY POINTS: ORBITAL INFECTIONS
1. The most common source of an orbital infection is an adjacent sinus. 2. Bacterial infection is the most common cause of cellulitis.
3. The orbital septum defines preseptal vs orbital cellulitis.
4. Orbital cellulitis in adults is usually caused by multiple organisms vs a single organism in children. 5. Intravenous antibiotics are required to treat orbital cellulitis.
29.What are the major categories of orbital vasculitis?
Granulomatosis with polyangiitis (GPA; formerly known as Wegener’s granulomatosis), hypersensitivity vasculitis, polyarteritis nodosa, and Churg-Strauss syndrome.
30.What is Wegener’s granulomatosis?
Wegener’s granulomatosis is an outdated term. The condition is now referred to as granulomatosis with polyangiitis, which provides a better description of the pathophysiology of the disease.
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