Uveal effusion syndrome
Uveal effusion syndrome is a rare syndrome of idiopathic exudative detachments of choroid, ciliary body and retina, thought to arise from impaired posterior segment drainage usually associated with scleral thickening.
Idiopathic uveal effusion syndrome usually affects healthy middle-aged men. However, there are no specific risk factors for the disease.
- H31.4 Choroidal detachment
- H31.8 Other specified disorders of choroid
Uveal effusion syndrome was described for the first time in 1963 by RJ Brockhurst. In 1983, JMD Gass hypothesized that the primary underlying cause of the idiopathic uveal effusion syndrome is a congenital anomaly of the sclera, and in some cases, the vortex veins .
It is sometimes divided into three types :
- Nanophthalmic eyes – type 1. The eyeball is small (average axial length 16 mm) and high hypermetropic (average +16 diopters).
- Non-nanophthalmic eyes with clinically abnormal sclera – type 2. The eyeball size is normal (average axial length 21 mm) with small refractive error.
- Non-nanophthalmic eyes with clinically normal sclera – type 3.
Nanophthalmos plus the presence of clinically detectable thickened/rigid sclera is a good predictor for histologically abnormal sclera and provides a good response to surgery .
Histologically, types 1 and 2 demonstrate abnormal sclera with disorganization of collagen fiber bundles and deposits of proteoglycans in the matrix, whereas type 3 shows normal sclera .
The pathogenesis of uveal effusion syndrome, also referred to as idiopathic ciliochoroidal effusion, though has not been clearly defined.
The pathogenesis of uveal effusion syndrome may involve a primary scleral abnormality that predisposes the eye to vortex vein obstruction and acts as a barrier to diffusion of extravascular protein out of the eye. The precise scleral abnormality, however, has not yet been elucidated. Certain scleral characteristics that may influence protein and fluid egress from the eye include scleral thickness, scleral composition, and the number of scleral emissary channels.
Increased scleral thickness may hamper the escape of aqueous by the uveo-scleral route. Thickened sclera may cause secondary vortex vein compression and can be implicated in the pathogenesis of uveal effusion syndrome and in nanophthalmic effusions. Nanophthalmic uveal effusion syndrome can be associated with reduced scleral permeability to albumin, and a very high concentration of retained suprachoroidal albumin. This will lead to an osmotic gradient that retains fluid and may partly explain the pathogenesis of uveal effusion syndrome in some patients.
The resultant elevation in tissue colloid osmotic pressure may lead to the accumulation of suprachoroidal fluid, and subsequent RPE decompensation may lead to the development of an exudative retinal detachment. Linear areas of RPE hypertrophy and hyperplasia may also be observed in chronic effusions.
Vision loss, blurred vision
IOP is normal or elevated
Detachments of choroid and ciliary body
Non-rhegmatogenous retinal detachment with shifting fluid as the subretinal fluid is heavy and contains proteins
Evidence of uveal, retinal, or vitreous inflammation is minor or absent
Localized areas of RPE hypertrophy and hyperplasia (“leopard spots”)
- FAG - rules out other causes of exudative retinal detachment.
- Ultrasound Biomicroscopy- to measure scleral thickness 2 mm and 3 mm posterior to the scleral spur.
Differential diagnosis should include choroidal melanoma, Vogt-Koyanagi-Harada disease, choroiditis, posterior scleritis, central serous retinopathy, hypertension, and metastases.
Treatment with systemic steroids does not appear to be effective.
Surgical decompression of the vortex veins has been described, though the most common treatment is full-thickness sclerectomies to provide a choroidal fluid drainage. An exit of subchoroidal fluid can be performed by full-thickness sclerectomy, subscleral sclerectomy, with or without the application of mitomycin C.
Vitrectomy has been described for management of uveal effusion syndrome. In cases of uveal effusion without nanophthalmic, vitrectomy hastens quick reattachment of the retina and may result in better visual outcome. In cases of nanophthalmic eyes, it would be better to perform sclerectomy first .
The largest case series suggests that sclerectomy produces an anatomic improvement in approximately 83% of treated eyes after a single procedure and in about 96% after one or two procedures. Final visual acuity improves by two or more lines in 56% of the eyes, is stable in 35%, and worsens in 9%. Although extremely rare, UES is a serious condition that is difficult to treat and can lead to severe and permanent visual loss in both eyes .
- Gass JD. Uveal effusion syndrome. A new hypothesis concerning pathogenesis and technique of surgical treatment.Retina. 1983; 3(3):159-63.
- Uyama M, Takahashi K, Kozaki J, Tagami N, Takada Y, Ohkuma H, Matsunaga H, Kimoto T, Nishimura T. Uveal effusion syndrome: clinical features, surgical treatment, histologic examination of the sclera, and pathophysiology.Ophthalmology. 2000 Mar; 107(3):441-9.
- Ohkita T, Emi K, Toyoda E, Ueno C, Sawada K, Sawada K, Matsumura N, Morita S, Kashimoto D, Oyagi T, Ikeda T. Efficacy of vitreous surgery for uveal effusion syndrome. Nihon Ganka Gakkai Zasshi. 2008 May; 112(5):472-5.
- Elagouz M, Stanescu-Segall D, Jackson TL. Uveal effusion syndrome. Surv Ophthalmol. 2010 Mar-Apr;55(2):134-45.
- Brockhurst RJ. Nanophthalmos with uveal effusion: a new clinical entity. Trans Am Ophthalmol Soc. 1974; 72:371-403.
- Jackson TL, Hussain A, Salisbury J, Sherwood R, Sullivan PM, Marshall J. Transscleral albumin diffusion and suprachoroidal albumin concentration in uveal effusion syndrome. Retina. 2012 Jan; 32(1):177-82.
- Matlach J, Nowak J, Göbel W. A novel technique for choroidal fluid drainage in uveal effusion syndrome. Ophthalmic Surg Lasers Imaging Retina. 2013 May-Jun; 44(3):274-7.
- Chan W, Fang-tian D, Hua Z, You-xin C, Rong-ping D, Ke T. Diagnosis and treatment of uveal effusion syndrome: a case series and literature review. Chin Med Sci J. 2011 Dec; 26(4):231-6.