**3. Uveitic entities associated with glaucoma**

**2. Pathogenesis of uveitic glaucoma**

due to increase in outflow resistance.

360 Glaucoma - Basic and Clinical Aspects

result in increased IOP. [9], [10]

prostaglandins.

Imbalance between aqueous humour secretion and clearance due to the intraocular inflam‐ mation may result in change in IOP. The IOP is often reduced because of hyopsecretion in conjunction with increased uveoscleral outflow. However, the IOP may be also increased

Several mechanisms are involved in the pathogenesis of glaucoma and this group of diseas‐ es may be divided to open and closed angle. Open angle is the largest group. In open angle glaucoma, increased outflow resistance is caused by obstruction of the trabecular meshwork by inflammatory cells, plasma proteins, fibrin and/ or debris. All of these are released from the blood vessels due to loss of aqueous-blood barrier and accumulate in the anterior cham‐ ber and the angle. Another mechanism is dysfunction of the trabeculocytes caused by toxici‐ ty of blood borne-products. This eventually may result in loss of trabeculocytes and scarring. Increased IOP may be caused by cytokines and prostaglandins. A role for the com‐ plement component C1qs has been implicated. [8] This component is part of the comple‐ ment system, which is activated in uveitis. Rho kinases that are released in uveitis may also

Corticosteroid-induced glaucoma is another mechanism for open angle glaucoma. It may oc‐ cur in up to one third of the patients but with impairment of the conventional outflow facili‐ ty in uveitic patients, it may increase even to 70%. [11] Corticosteroids are being routinely used for uveitis and they can cause this type of open angle glaucoma in any form although it is more common with topical installation. The development of glaucoma depends on the subject susceptibility (corticosteroid responder), dose, duration, type of medication and route of administration. The glaucoma may develop at any time after the initiation of treat‐ ment, but usually within 6 weeks. The glaucoma develops due to multiple mechanisms. Tra‐ becular cells have receptors for corticosteroids and they cause alternation of multiple gene expression leading to the production of extracellular glycosaminoglycans including fibro‐ nectin, laminin and collagen. [12] They also decrease the turnover of the extracellular matrix by inhibiting matrix metaloproteinases (MMPs) and tissue plasminogen activator and in‐ creasing plasminogen activator inhibitor 1 and tissue inhibitors of MMPs. Therefore, the gly‐ cosaminoglycans accumulate in the angle. The corticosteroids also cause inhibition of phagocytosis, proliferation and migration of the trabeculocytes, and formation of certain

Secondary angle closure glaucoma may occur as chronic and acute forms. In chronic angle closure glaucoma, peripheral anterior synechiae (PAS) develop along the angle. They are be‐ ing developed due to organization of inflammatory products in the angle. These PAS are broad base, trapezoid and highly pigmented bands that bridge the peripheral iris with the corneal periphery obstructing the angle. They may widen with time, resulting eventually in closure of the angle and increased IOP. Because the angle is progressively closing, the IOP increases gradually without causing an acute stage of increased IOP and without corneal edema. The acute form of angle closure glaucoma occurs secondary to papillary block be‐ cause of 360° of posterior synechiae. These synechiae develop between the posterior margin

#### **3.1. Glaucomatocyclitic crisis (Posner-Schlossman syndrome)**

Glaucomatocyclitic crisis is characterized by recurrent episodes of increased IOP and anteri‐ or chamber inflammation. Therefore, the uveitis is always accompanied by glaucoma and vice versa. In between, the eye is quiet and the IOP is normal. The disease is usually unilat‐ eral and involves the same eye.

Patients complain of blurred or decreased vision and ocular discomfort. Minimal flare and cells (usually +1 or 5-10 cells per wide field magnification of X40) are found in the anterior chamber along with increase in IOP in the range of 40-60mmHg that may reach 70mmHg. Iris heterochromia may appear after recurrent attacks. The first attack is always the most challenging to diagnose. When subsequent episodes occur, the diagnosis is obvious and the patient is aware when they occur. The disease usually appears at the 3rdto 4th decade.

The pathogenesis of the disease is not well established. Viral infection by herpes and cyto‐ megalic viruses, allergic factors and immunogenetic factors related to HLA-Bw54 have been suggested. [13-16] It may also be related to certain prostaglandins such as E released due to vascular incompetence. [17] Indeed, prostaglandin inhibitors, oral indomethacin and sub‐ conjunctival polyphloretin, a prostaglandin antagonist have been demonstrated to decrease the IOP. [17], [18]

The disease responds to medical treatment with topical corticosteroid (prednisolone acetate 1% qid) and anti-glaucoma medications such as beta-blockers (timolol 0.5% bid) and carbon‐ ic anhydrase inhibitors (acetazolamide 250mg bid or tid). [19] Topical IOP sparing cortico‐ steroids and non-steroidal anti-inflammatory drugs may replace the classic corticosteroids. Prostaglandin inhibitors, oral indomethacin 75-150mg/day and subconjunctival polyphlore‐ tin, a prostaglandin antagonist, may also decrease the IOP. No preventive treatment during the remissions is known. In rare cases in which progression in optic disc and visual field damage is demonstrated, trabeculectomy or stenting procedure may be performed. The prognosis is good and some claim that the frequency of the attacks decreaseage. Unfortu‐ nately, no prophylactic treatment exists. The risk of developing optic disc and visual field damage is increased with the duration of the disease. Patients with 10 years or more of dis‐ ease have a risk of 2.8 folds to develop damage than those with duration of less than 10 years.

**3.3. Glaucoma in juvenile idiopathic arthritic (JIA) uveitis**

glaucoma may also develop.

ment with oral methotrexate 15mg/m2

**3.4. Sarcoidosis**

ate is not tolerable or when remission is not achieved.

Secondary glaucoma may develop in 14-42% of the patients with JIA. [22]-[24] The glauco‐ ma is usually open angle. However, papillary block glaucoma and chronic angle closure

The patient is usually asymptomatic and the eye is quiet. Therefore, any child with pauciar‐ ticular arthritis should be referred to ophthalmologic examination every 6 months. If uveitis presents, flare and cells will be present in the anterior segment. In cases of uveitis, measure‐ ment of the IOP and evaluation of the optic disc are mandatory. Both the uveitis and glauco‐ ma should be treated early and aggressively. The uveitis is treated in a stepladder manner. The purpose of the treatment is to achieve remission but treatment should be continued even after its achievement. First, topical corticosteroid (prednisolone acetate 1% every 1-2 hours) and cycloplegic (cyclopentholate 1% tid) agent are being used. [25] Change to IOPsparing or less potent corticosteroids should be performed only when the initial inflamma‐ tion decreased. If treatment with corticosteroid fails, oral NSAID such as naprosyn (Naproxen®) 5mg/kg twice a day is being used and if this fails, immunosuppressive treat‐

up to 30mg/m2

ployed. Common side effects of methotrexate include nausea, anorexia, stomatitis and transient elevation of serum aminotransferase. Alopecia, hematological toxicity, headache, dizziness, fatigue, and mood changes may also occur. A "post-dosing" reaction may occur within 24 hours of receiving methotrexate and is usually characterized by malaise, fatigue, gastrointestinal upset, and occasionally central nervous system manifestations. Liver cirrho‐ sis is a long-term potential complication. Other immunomodulators, such as oral cyclospor‐ ine (2-5 mg/kg/day), azathioprine (1-2mg/kg per day), mycophenolate mofetil (300mg/m2 body surface area bid), or chlorambucil (0.10-0.16 mg/kg/day) may be used when methotrex‐

A multi-organ inflammatory disease that is prevalent in blacks. The patients have pulmona‐ ry hilar lymphadenopathy, peripheral lymphadenopathy and cutaneous non-caseating epi‐ thelioid granulomas. Ocular involvement occurs in 38% of the patients and may be the first manifestation of the disease. [26] Anterior uveitis is the most common ocular manifestation. At the beginning, the uveitis appears as acute iridocyclitis. A characteristic but not patho‐ gnomonicsign is large (mutton fat) keratic precipitates (KPs) over the endothelium. The dis‐ ease may become chronic and bilateral. The mutton fat PKs are usually encountered at this stage along with Koeppe's nodules on the iris margins and Busacca's nodules on the iris sur‐ face. Nodules may also appear in the angle and over the ciliary body. Open angle glaucoma is present in 11%. The usual pathogenesis is obstruction of the angle by inflammatory cells and debris. The disease may mistakenly be considered as Fuchs' heterochromic iridocyclitis. Elevated serum angiotensin converting enzyme or a positive Kveim test will confirm the di‐ agnosis of sarcoid. Additional tests include Gallium [67] scan that shows high intake in the lacrimal and parotid lymph nodes with or without submandibular lymph nodes and serum‐ lysozyme, which is increased. Treatment includes topical corticosteroid (prednisolone ace‐

(or 03-0.5mg/kg) once a week is em‐

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**Figure 1.** Posner-Schlossman syndrome. Note the few keraticprover the endothelium.

#### **3.2. Fuchs' heterochromic iridocyclitis**

The disease is characterized by iris heterochromia and chronic, low-grade iridocyclitis. It ap‐ pears in the 2ndto 4thdecade and is unilateral in 87% of the patients. [20]

The patients may be asymptomatic or may complain of a decrease in vision or change iris color. On examination, heterochromia along with low-grade anterior chamber reaction (flare and cells +1) are noted. Fine keratic precipitates may be noted as well. Secondary open angle glaucoma develops in 13-59% of the patients depending on the duration of the disease. It is more frequent in patients with bilateral disease and in African descends. Posterior subcap‐ sular cataract may also develop.

Treatment for Fuchs' dystrophy without glaucoma is not required since it poorly responds to corticosteroids. The glaucoma may develop late in the course of the disease. Anti-glauco‐ ma medications may be effective initially but later the medical treatment usually fails and filtration surgery is required. [21]

**Figure 2.** Fuchs' heterochromic iridocyclitis in the right eye. The differential diagnosis for a brighter involved iris is con‐ genital and acquired Horner syndrome (with 2mm ptosis and miosis) and more rarely Posner Schlosmann syndrome and for darker involved iris, siderosis bulbi.

#### **3.3. Glaucoma in juvenile idiopathic arthritic (JIA) uveitis**

Secondary glaucoma may develop in 14-42% of the patients with JIA. [22]-[24] The glauco‐ ma is usually open angle. However, papillary block glaucoma and chronic angle closure glaucoma may also develop.

The patient is usually asymptomatic and the eye is quiet. Therefore, any child with pauciar‐ ticular arthritis should be referred to ophthalmologic examination every 6 months. If uveitis presents, flare and cells will be present in the anterior segment. In cases of uveitis, measure‐ ment of the IOP and evaluation of the optic disc are mandatory. Both the uveitis and glauco‐ ma should be treated early and aggressively. The uveitis is treated in a stepladder manner. The purpose of the treatment is to achieve remission but treatment should be continued even after its achievement. First, topical corticosteroid (prednisolone acetate 1% every 1-2 hours) and cycloplegic (cyclopentholate 1% tid) agent are being used. [25] Change to IOPsparing or less potent corticosteroids should be performed only when the initial inflamma‐ tion decreased. If treatment with corticosteroid fails, oral NSAID such as naprosyn (Naproxen®) 5mg/kg twice a day is being used and if this fails, immunosuppressive treat‐ ment with oral methotrexate 15mg/m2 up to 30mg/m2 (or 03-0.5mg/kg) once a week is em‐ ployed. Common side effects of methotrexate include nausea, anorexia, stomatitis and transient elevation of serum aminotransferase. Alopecia, hematological toxicity, headache, dizziness, fatigue, and mood changes may also occur. A "post-dosing" reaction may occur within 24 hours of receiving methotrexate and is usually characterized by malaise, fatigue, gastrointestinal upset, and occasionally central nervous system manifestations. Liver cirrho‐ sis is a long-term potential complication. Other immunomodulators, such as oral cyclospor‐ ine (2-5 mg/kg/day), azathioprine (1-2mg/kg per day), mycophenolate mofetil (300mg/m2 body surface area bid), or chlorambucil (0.10-0.16 mg/kg/day) may be used when methotrex‐ ate is not tolerable or when remission is not achieved.

#### **3.4. Sarcoidosis**

**Figure 1.** Posner-Schlossman syndrome. Note the few keraticprover the endothelium.

pears in the 2ndto 4thdecade and is unilateral in 87% of the patients. [20]

The disease is characterized by iris heterochromia and chronic, low-grade iridocyclitis. It ap‐

The patients may be asymptomatic or may complain of a decrease in vision or change iris color. On examination, heterochromia along with low-grade anterior chamber reaction (flare and cells +1) are noted. Fine keratic precipitates may be noted as well. Secondary open angle glaucoma develops in 13-59% of the patients depending on the duration of the disease. It is more frequent in patients with bilateral disease and in African descends. Posterior subcap‐

Treatment for Fuchs' dystrophy without glaucoma is not required since it poorly responds to corticosteroids. The glaucoma may develop late in the course of the disease. Anti-glauco‐ ma medications may be effective initially but later the medical treatment usually fails and

**Figure 2.** Fuchs' heterochromic iridocyclitis in the right eye. The differential diagnosis for a brighter involved iris is con‐ genital and acquired Horner syndrome (with 2mm ptosis and miosis) and more rarely Posner Schlosmann syndrome

**3.2. Fuchs' heterochromic iridocyclitis**

362 Glaucoma - Basic and Clinical Aspects

sular cataract may also develop.

filtration surgery is required. [21]

and for darker involved iris, siderosis bulbi.

A multi-organ inflammatory disease that is prevalent in blacks. The patients have pulmona‐ ry hilar lymphadenopathy, peripheral lymphadenopathy and cutaneous non-caseating epi‐ thelioid granulomas. Ocular involvement occurs in 38% of the patients and may be the first manifestation of the disease. [26] Anterior uveitis is the most common ocular manifestation. At the beginning, the uveitis appears as acute iridocyclitis. A characteristic but not patho‐ gnomonicsign is large (mutton fat) keratic precipitates (KPs) over the endothelium. The dis‐ ease may become chronic and bilateral. The mutton fat PKs are usually encountered at this stage along with Koeppe's nodules on the iris margins and Busacca's nodules on the iris sur‐ face. Nodules may also appear in the angle and over the ciliary body. Open angle glaucoma is present in 11%. The usual pathogenesis is obstruction of the angle by inflammatory cells and debris. The disease may mistakenly be considered as Fuchs' heterochromic iridocyclitis. Elevated serum angiotensin converting enzyme or a positive Kveim test will confirm the di‐ agnosis of sarcoid. Additional tests include Gallium [67] scan that shows high intake in the lacrimal and parotid lymph nodes with or without submandibular lymph nodes and serum‐ lysozyme, which is increased. Treatment includes topical corticosteroid (prednisolone ace‐ tate 1% every 1-2 hours) and cycloplegic agent. If the posterior segment is involved, sub-Tenon and or oral corticosteroids (see the section on medical treatment of uveitic glaucoma below) are added. The sub-Tenon injections of corticosteroids may be repeated weekly. However, they should be cautiously used if glaucoma exists. Immunosuppressive agents such as methotrexate should replace corticosteroids if there is no response or contraindica‐ tions such as steroid-induced glaucoma. In resisting cases, anti-tumor necrosis factor alpha (TNFα) such as infliximab, etanercept, or adalimumab and intravitreal anti-vascular endo‐ thelial growth factor such as bevacizumab may be employed. Anti-glaucoma medications are indicated. Generally, the long-term prognosis is poor.

pears in 2-15% and is frequently associated with cataract and microphthalmia. [29] The pathogenesis is multi-factorial. Congenital angle abnormalities, chronic iridocyclitis, papil‐ lary block and angle closure glaucoma from intumescent cataract or microphthalmia are im‐ plicated. The glaucoma may appear at any age and therefore routine follow-up that includes measurement of the IOP and evaluation of the optic disc is required for lifetime. It should be performed at least every 6 months. If glaucoma is diagnosed, treatment should be aggres‐ sive and follow-up should be frequent to prevent blindness since it may occur in 44%. A pe‐ ripheral iridectomy should be performed if cataract surgery is performed to deepen the

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Any patient with chronic or recurrent anterior uveitis from unknown cause may develop glaucoma. Thus, in all patients with chronic or recurrent uveitis, IOP measurements should be obtained. Independently, medical treatment for the uveitis and for the glaucoma should

Phacoanaphylaxis is a granulomatous uveitis from liberated crystalline lens proteins and contact with blood circulation. This disorder may be classified also as part of the lens-in‐ duced glaucomas. [30] It is the result of cataract extraction or traumatic lens rupture. The disorder may occur any time after surgery or trauma. It may occur spontaneously usually in microphthalmic eyes. It is type III hypersensitivity (immune complex). It usually causes hy‐ potony and rarely pupillary block glaucoma or angle closure glaucoma from peripheral an‐ terior synechiae. Keratic precipitates may appear on the cornea and the intraocular lens (IOL), hypopion and numerous white cells in the anterior chamber and vitreous may be present. Remnants of the crystalline lens are always present, while cultures are negative. Anterior chamber tap reveals foamy macrophages (as seen in phacolytic glaucoma). A high suspicion index is required because the disease may be similar to infectious endophthalmitis (but without pain), sterile endophthalmitis and toxic anterior chamber reaction (fibrinoid re‐ action). The respond to corticosteroids is temporary and removal of the lens remnants is the

Uveitis-glaucoma-hyphema (UGH) syndrome is a triad classically caused by subluxated or mal-positioned IOL (usually an anterior chamber IOL) rubbing against the iris and causing release of pigment and bleeding that result in open angle glaucoma. [31] If vitreous hemor‐ rhage also presents, the condition is called UGH plus. Incomplete UGH is when uveitis and sometimes glaucoma are absent. The condition may also be caused by excessive movement of a small IOL. The patient complaints are sudden (within minutes to hours) decrease in vi‐ sion that gradually improves over hours to days, and sometimes, ocular pain. The patient may describe his vision as "white-out" or having reddish tint (erythropsia). The condition occurs from one week to months after surgery. It is diagnosed by attacks of this triad and

anterior chamber and to prevent papillary block glaucoma.

**3.8. Phacoanaphylactic uveitis (phacoantigenic uveitis)**

**3.9. Uveitis-glaucoma-hyphema (UGH) syndrome**

be initiated to achieve remission of the inflammation and control the IOP.

**3.7. Glaucoma in idiopathic uveitis**

treatment of choice.

#### **3.5. Herpetic keratouveitic glaucoma**

Secondary open angle glaucoma may develop in herpetic keratouveitis in 10-54%. [27], [28] The disease appears weeks to years after recurrent episodes of keratouveitis with either stro‐ mal keratitis (96%) or metaherpetic ulcer (4%). The pathogenesis is probably a complex of direct injury to the trabeculocytes by the virus, inflammatory products and response to cor‐ ticosteroids. The condition is responsive to medical treatment with topical corticosteroid and antiglaucoma medications such as β-blockers, α-agonists and topical and oral carbonic anhydrase inhibitors. In patients with several episodes of keratouveitis in a year, oral acyclo‐ vir 400 mg bid for a year or more may decrease the recurrences.

**Figure 3.** Glaucoma in herpetic keratouveitis. Note the mild stromal haze from stromal keratitis and posterior syne‐ chia.

#### **3.6. Congenital rubella**

Congenital rubella affects the heart, auditory system and the eye. It may cause cataract, ret‐ inopathy, glaucoma and microphthalmia in 30-60% of the affected children. Glaucoma ap‐ pears in 2-15% and is frequently associated with cataract and microphthalmia. [29] The pathogenesis is multi-factorial. Congenital angle abnormalities, chronic iridocyclitis, papil‐ lary block and angle closure glaucoma from intumescent cataract or microphthalmia are im‐ plicated. The glaucoma may appear at any age and therefore routine follow-up that includes measurement of the IOP and evaluation of the optic disc is required for lifetime. It should be performed at least every 6 months. If glaucoma is diagnosed, treatment should be aggres‐ sive and follow-up should be frequent to prevent blindness since it may occur in 44%. A pe‐ ripheral iridectomy should be performed if cataract surgery is performed to deepen the anterior chamber and to prevent papillary block glaucoma.

### **3.7. Glaucoma in idiopathic uveitis**

tate 1% every 1-2 hours) and cycloplegic agent. If the posterior segment is involved, sub-Tenon and or oral corticosteroids (see the section on medical treatment of uveitic glaucoma below) are added. The sub-Tenon injections of corticosteroids may be repeated weekly. However, they should be cautiously used if glaucoma exists. Immunosuppressive agents such as methotrexate should replace corticosteroids if there is no response or contraindica‐ tions such as steroid-induced glaucoma. In resisting cases, anti-tumor necrosis factor alpha (TNFα) such as infliximab, etanercept, or adalimumab and intravitreal anti-vascular endo‐ thelial growth factor such as bevacizumab may be employed. Anti-glaucoma medications

Secondary open angle glaucoma may develop in herpetic keratouveitis in 10-54%. [27], [28] The disease appears weeks to years after recurrent episodes of keratouveitis with either stro‐ mal keratitis (96%) or metaherpetic ulcer (4%). The pathogenesis is probably a complex of direct injury to the trabeculocytes by the virus, inflammatory products and response to cor‐ ticosteroids. The condition is responsive to medical treatment with topical corticosteroid and antiglaucoma medications such as β-blockers, α-agonists and topical and oral carbonic anhydrase inhibitors. In patients with several episodes of keratouveitis in a year, oral acyclo‐

**Figure 3.** Glaucoma in herpetic keratouveitis. Note the mild stromal haze from stromal keratitis and posterior syne‐

Congenital rubella affects the heart, auditory system and the eye. It may cause cataract, ret‐ inopathy, glaucoma and microphthalmia in 30-60% of the affected children. Glaucoma ap‐

are indicated. Generally, the long-term prognosis is poor.

vir 400 mg bid for a year or more may decrease the recurrences.

**3.5. Herpetic keratouveitic glaucoma**

364 Glaucoma - Basic and Clinical Aspects

chia.

**3.6. Congenital rubella**

Any patient with chronic or recurrent anterior uveitis from unknown cause may develop glaucoma. Thus, in all patients with chronic or recurrent uveitis, IOP measurements should be obtained. Independently, medical treatment for the uveitis and for the glaucoma should be initiated to achieve remission of the inflammation and control the IOP.

#### **3.8. Phacoanaphylactic uveitis (phacoantigenic uveitis)**

Phacoanaphylaxis is a granulomatous uveitis from liberated crystalline lens proteins and contact with blood circulation. This disorder may be classified also as part of the lens-in‐ duced glaucomas. [30] It is the result of cataract extraction or traumatic lens rupture. The disorder may occur any time after surgery or trauma. It may occur spontaneously usually in microphthalmic eyes. It is type III hypersensitivity (immune complex). It usually causes hy‐ potony and rarely pupillary block glaucoma or angle closure glaucoma from peripheral an‐ terior synechiae. Keratic precipitates may appear on the cornea and the intraocular lens (IOL), hypopion and numerous white cells in the anterior chamber and vitreous may be present. Remnants of the crystalline lens are always present, while cultures are negative. Anterior chamber tap reveals foamy macrophages (as seen in phacolytic glaucoma). A high suspicion index is required because the disease may be similar to infectious endophthalmitis (but without pain), sterile endophthalmitis and toxic anterior chamber reaction (fibrinoid re‐ action). The respond to corticosteroids is temporary and removal of the lens remnants is the treatment of choice.

#### **3.9. Uveitis-glaucoma-hyphema (UGH) syndrome**

Uveitis-glaucoma-hyphema (UGH) syndrome is a triad classically caused by subluxated or mal-positioned IOL (usually an anterior chamber IOL) rubbing against the iris and causing release of pigment and bleeding that result in open angle glaucoma. [31] If vitreous hemor‐ rhage also presents, the condition is called UGH plus. Incomplete UGH is when uveitis and sometimes glaucoma are absent. The condition may also be caused by excessive movement of a small IOL. The patient complaints are sudden (within minutes to hours) decrease in vi‐ sion that gradually improves over hours to days, and sometimes, ocular pain. The patient may describe his vision as "white-out" or having reddish tint (erythropsia). The condition occurs from one week to months after surgery. It is diagnosed by attacks of this triad and the presence of iris transillumination corresponding to the rubbing site. The diagnosis is easiest during the attack. A blood cloth or hyphema may be observed. The diagnosis can be confirmed by ultrasound biomicroscopy (UBM) and anterior segment optical coherence to‐ mography (AS-OCT) showing a contact between the optic or haptic and the iris. The compli‐ cations include pseudophakic bullous keratopathy, corneal staining and cystoid macular edema (CME). The differential diagnosis includes amaurosis fugax and vertebrobasilar in‐ sufficiency. Amaurosis fugax occurs more rapidly (within seconds to minutes) and loss of light perception in at least one quadrant. Loss of light perception never occurs in UGH syn‐ drome and there is always a history of cataract extraction and IOL implantation or iris de‐ vice implantation. The differentiation between the two is crucial because patients with amaurosis fugax may be treated with anti-coagulants that may increase the bleeding in UGH syndrome. Patients may respond to topical corticosteroids and anti-glaucoma medica‐ tions. The definite treatment of UGH is replacement or repositioning of the IOL.

**5. Diagnosis**

should decrease.

**6. Medical treatment**

gle closure glaucoma are asymptomatic.

Patients with acute closed-angle glaucoma may present with ocular and brow ace, blurred vision, halos, photophobia and even nausea and vomiting. Patients with open or chronic an‐

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All uveitis patients should be routinely evaluated for IOP, which is elevated (>21mmHg) in uveitic glaucoma. In acute closed angle glaucoma, the cornea may be edematous and ciliary and conjunctival congestion may be present. Gonioscopy should be performed to define the type of glaucoma. Topical glycerin 50-100% would clear corneal edema for evaluating the angle and posterior segment. Otherwise, the corneal epithelium may be removed with a blade or 70% alcohol on a cotton-tipped applicator. If the cornea is still cloud, UBM or AS-OCT may replace gonioscopy in evaluating is performed the angle. Optic disc evaluation by slit lamp biomicroscopy and other imaging techniques (OCT, scanning laser polarimetry (GDx) or Heidelberg retinal tomography (HRT)) when the cornea is clear. Visual fields should be obtained in patients with cup/disc ratio of 0.6 or more for baseline and follow-up documentation of the progression of the glaucoma. In patients with cup/disc ratio of less than 0.6, the visual field is usually normal. The visual field may be abnormal due to CME (central relative scotoma) and retinitis or retinal scarring (defects corresponding to these areas). CME and macular atrophy may be confirmed by OCT. Differentiation should be made between steroid responder (the IOP returns to normal upon discontinuation of the corticosteroids) and corticosteroid-induced glaucoma (the IOP remains high). Differentia‐ tion between increased IOP due to increased inflammation and steroid responder may be performed by replacing the corticosteroids with IOP-sparing corticosteroids. The IOP

Treatment is aimed to control both the uveitis and IOP. The uveitis is treated by topical and/or systemic corticosteroids and/ or immunosuppressive drugs to achieve resolution or remission. Sub-Tenon corticosteroids such as triamcinolone acetonid (Kenalog®) 20-40mg (0.5-1ml) or methylprednisolone acetate (Depo-medrol®) 40-80mg may be given to treat noninfectious uveitis and macular edema. Intravitreal implants such as Ozurdex®, a copoly‐ mer of glycolic and lactic acid with 700µg of dexamethasone may be injected through the pars plana with 22G injector. It dissolves gradually over 6 months to H2O and CO2 and re‐ leases the dexamethasone. However, they all and especially those that cannot be removed (sub-Tenon and intravitreal) should be used cautiously in patients with glaucoma and are contraindicated in steroid responders and steroid-induced glaucoma. In cases of steroid res‐ ponders orcorticosteroid-induced glaucoma, topical corticosteroids may be replaced by IOPsparing corticosteroids such as such as loteprednol etabonate 0.5% (Lotemax®) or rimexolone 1%(Vexol®) but because of low potency, they may be more frequently required. These agents are especially useful for maintenance. Alternatively, topical non-steroidal anti-
