Uveitis intermediate

An additional clinical use of acetazolamide is unrelated to its ocular hypotensive properties.The 500-mg acetazolamide capsule administered daily for 2 weeks may produce either a partial or a complete resolution of macular edema in patients with cystoid macular edema (CME), retinitis pigmentosa, and chronic intermediate uveitis (pars planitis). Macular edema produced by primary retinal vascular diseases (branch and central retinal vein occlusion and macular telangiectasia) did not respond to acetazolamide therapy. It is believed that acetazolamide may improve visual function if the macular edema stems from retinal pigment epithelial dysfunction. Improved macular edema in these conditions may be associated with fluid movement from the retina to the choroid. However, acetazolamide does not appear to alter macular blood flow. 

Intermediate uveitis Describes inflammation confined to the posterior aspect of the ciliary body (pars plana) and/or the peripheral choroid. Secondary involvement of the retina and vitreous may also be seen. The most common form of intermediate uveitis in the United States is pars planitis. 

Intermediate uveitis tends to affect younger patients, ranging from their teens to early forties. The most common presentation involves vague complaints of blurry vision and persistent floaters, with a slow insidious onset. Pain and photophobia are imcommon symptoms. Whereas the signs of anterior uveitis are primarily seen in the aqueous and iris, the diagnosis of intermediate uveitis typically involves evaluation of the vitreous and peripheral retina. Bilateral involvement at initial presentation is near 80%, and approximately one-third of unilateral cases ultimately become bilateral. Intermediate uveitis has been reported... 

Visual acuity is often compromised on presentation in intermediate uveitis. A study in 2001 found a mean entering visual acuity of 6/12 (20/40) in patients with pars planitis on average, children with this disease were foimd to have worse visual acuity than adults at the time of initial presentation. CME is the most common cause of reduced acuity in intermediate uveitis. Other complications, including chronic vitreitis, cataract, and band keratopathy, may ensue in cases of untreated or undertreated intermediate uveitis, resulting in potentially significant visual compromise. 

External evaluation is often fruitless in cases of intermediate uveitis, because there are generally no outward signs of inflammation. The eye appears white, and pupillary reaction is rarely compromised. There is typically no pain or photophobia on pupil or motility testing. 

Biomicroscopy of the anterior segment typically reveals little in cases of intermediate uveitis, although occasionally a few spillover cells may be seen in the aqueous. Hallmark findings of anterior uveitis, such as conjimctival hyperemia, KPs, and iris nodules, are characteristically absent. Late-stage findings may include corneal band keratopathy, anterior and/or posterior synechia, and cataract (most commonly of the posterior subcapsular variety). 

Because intermediate uveitis does not involve the ciliary body or trabecular meshwork, lOP is rarely impacted by this disease course. However, should late-stage changes occur in the anterior chamber (e.g., synechiae, iris neovascularization), the clinician is obligated to perform tonometry and monitor for secondary glaucoma. Also, use of topical, injectable, and/or systemic corticosteroids in the treatment of uveitis may induce a precipitous rise in lOP, resulting in steroid-induced glaucoma. 

It is important to perform gonioscopy only in recalcitrant cases of intermediate uveitis to rule out complications such as peripheral anterior synechia and neovascularization. Otherwise, this test is superfluous. 

The most critical aspect of diagnosing intermediate uveitis involves inspection of the posterior segment through a dilated pupil. Inspection of the anterior vitreous through the biomicroscope may reveal white cells... 

Deeper or more severe forms of uveitis may not respond to topical therapy hence, injectable and/or oral routes of administration may be required. Periocular corticosteroids may be used occasionally for anterior uveitis however, this therapy is more often used in cases of intermediate uveitis or, less commonly, unilateral posterior uveitis.A small amount of depot corticosteroid (e.g., 1 ml of 40 mg/ml triamcinolone acetonide injected superiorly or inferiorly in the orbit) is considered acceptable and appropriate treatment in such situations. In cases of chronic posterior uveitis or uveitis associated with CME, intravitreal triamcinolone has also been used with some success. A retrospective study in 2005 demonstrated that intravitreal injection of 4 mg/0.1 ml triamcinolone acetonide can effectively reduce CME and improve visual acuity and, in some eyes, allow for the reduction of immimosuppressive therapy. 

Oral corticosteroids represent the treatment of choice for bilateral posterior uveitis and nonresponsive anterior or intermediate uveitis. Prednisone 0.5 to 1.0 mg/kg... 

Intermediate uveitis may not warrant any therapeutic intervention in mild cases where the visual acuity is 20/40 or better. However, medical therapy is required for most patients. Macular edema is a frequent complication and requires prompt management to prevent permanent vision loss. In general, topical steroids are minimally effective in intermediate uveitis, except in those patients who are aphakic. Periocular and systemic steroids are substantially more efficacious. Periocular steroid injections are preferable in unilateral presentations and in children, whereas oral or other systemic routes are required for bilateral cases. For steroid-resistant intermediate uveitis, immunosuppressive therapy or surgery (cryotherapy and vitrectomy) may be necessary. Complications associated with intermediate uveitis include persistent CME,... 

Differential diagnosis of ocular toxocariasis includes retinoblastoma (frequently confused with toxocariasis). Coats disease, persistent hyperplastic primary vitreous, retinopathy of prematurity, femilial exudative vitreo-retinopathy, intermediate uveitis, toxoplasmosis, and idiopathic subretinal neovascular membranes. Because toxocariasis frequently mimics retinoblastoma, differential diagnosis is critical, because their treatments are radically different. 

Intermediate uveitis is a common manifestation of eye sarcoidosis. It is defined as inflammation of the vitreous, pars plana, and peripheral retina (1,3). Patients may be asymptomatic or complain of floaters or blurred vision (1,9). 

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