Major reviewMacular edema
Introduction
Macular edema represents a common pathologic sequel of the retina associated with a broad spectrum of potential insults. It consists of a localized expansion of the retinal intracellular and/or extracellular space in the macular area. This predilection to the macular region is probably associated with the loose binding of inner connecting fibers in Henle's layer, allowing accumulation of fluid leaking from perifoveal capillaries. The absence of Müller cells in the foveal region is also a contributing factor.
Radially orientated cystoid spaces consisting of ophthalmoscopically clear fluid are often clinically detectable in the macular area. The cysts are characterized by an altered light reflex with a decreased central reflex and a thin, highly reflective edge (Fig. 1).66 Histological studies show the cysts to be areas of retina in which the cells have been displaced. Recently Antcliff et al15 monitored the hydraulic conductivity of the human retina following progressive ablation of retinal layers performed with the aid of an excimer laser. They concluded that the inner and outer plexiform layers constitute high resistance barriers to fluid flow through the retina, which accounts for the characteristic distribution of cystoid macular edema (CME) seen in histological specimens and with optical coherence tomography (OCT).
In this review the etiology and investigative methods for the diagnosis and monitoring of macular edema are presented with an emphasis on current therapeutic modalities based on evidence from existing literature.
Section snippets
Etiology and Clinical Manifestations
A multitude of underlying conditions may result in macular edema. In this section the most common causes of macular edema are described with reports on its clinical manifestation in different clinical settings.
Investigations
Slit-lamp examination with contact or non-contact lens, makes it possible to detect retinal thickening, localized or extending to the posterior pole. The use of a narrow slit beam is useful in detecting cystoid spaces. Clinical suspicion of macular edema can be confirmed with the aid of a wide variety of investigations (Table 1). Tests may be grouped into three categories according to whether one is analyzing the underlying pathogenesis, the effect of the macular edema on the retina, or its
Medical
The challenge concerning the management of macular edema arises in the chronic and persistent case, for which a stepwise therapeutic approach is optimal. The clinician must always be alert to the possible side effects of the many effective, but potentially toxic, pharmaceutical agents used to treat this entity. Additionally, surgical management should be considered for unremitting cases of CME (Table 2).
Method of Literature Search
In this review, we identified pertinent articles on macular edema from a combination of sources including electronic database searches and manual searches through the literature. A computerized search of the PubMed database (National Library of Medicine) was performed up to January 2003. The term macular edema was used for a broad and sensitive search. Subsequently all the abstracts were carefully scanned and were divided into subcategories covering topics including pathogenesis, etiology,
References (203)
- et al.
Pseudophakic cystoid macular edema treated with high-dose intravenous methylprednisolone
J Cataract Refract Surg
(1999) - et al.
Intravitreal triamcinolone for uveitic cystoid macular edema: an optical coherence tomography study
Ophthalmology
(2001) - et al.
Long-term results of Nd:YAG laser posterior capsulotomy with the Swiss laser
J Cataract Refract Surg
(1986) - et al.
Locally administered hyperoxic therapy for aphakic cystoid macular edema
Am J Ophthalmol
(1992) - et al.
Natural course of nonaphakic cystoid macular edema
Surv Ophthalmol
(1984) - et al.
Prognosticators for visual outcome in sarcoid uveitis
Ophthalmology
(1996) - et al.
Dominantly inherited cystoid macular edema
Am J Ophthalmol
(1976) - et al.
Phacoemulsification versus extracapsular cataract extraction in patients with diabetes
Ophthalmology
(2000) - et al.
The natural history of macular edema after cataract surgery in diabetes
Ophthalmology
(1999) - et al.
Pars plana vitrectomy for intraocular inflammation-related cystoid macular edema unresponsive to corticosteroids. A preliminary study
Ophthalmology
(1992)
Effect of methazolamide on chronic macular edema in patients with retinitis pigmentosa
Ophthalmology
Effectiveness of ketorolac tromethamine 0.5% ophthalmic solution for chronic aphakic and pseudophakic cystoid macular edema
Am J Ophthalmol
Prophylaxis of aphakic cystoid macular edema without corticosteroids. A paired-comparison, placebo-controlled double-masked study
Ophthalmology
Extracapsular cataract extraction and posterior chamber intraocular lens implantation in uveitis patients
Ophthalmology
Vitrectomy for chronic aphakic cystoid macular edema. Results of a national, collaborative, prospective, randomized investigation
Ophthalmology
A clinical, fluorescein angiographic, and electron microscopic correlation of cystoid macular edema
Am J Ophthalmol
Prognostic factors for retinal vein occlusion: prospective study of 175 cases
Ophthalmology
Radiation maculopathy after proton beam irradiation for choroidal melanoma
Ophthalmology
Vitrectomy for diabetic macular edema associated with a thickened and taut posterior hyaloid membrane
Am J Ophthalmol
Pars plana vitrectomy for chronic pseudophakic cystoid macular edema
Am J Ophthalmol
Possible role of the vitamin E solubilizer in topical diclofenac on matrix metalloproteinase expression in corneal melting: an analysis of postoperative keratolysis
Ophthalmology
Topography of diabetic macular edema with optical coherence tomography
Ophthalmology
Ketorolac versus prednisolone versus combination therapy in the treatment of acute pseudophakic cystoid macular edema
Ophthalmology
Combination intravenous ceftazidime and aminoglycosides in the treatment of pseudomonal scleritis
Ophthalmology
The significance of the pars plana exudate in pars planitis
Am J Ophthalmol
Course of vitreomacular traction syndrome
Am J Ophthalmol
A newly defined vitreous syndrome following cataract surgery, interpreted according to recent concepts of the structure of the vitreous
Am J Ophthalmol
Fluocinolone acetonide sustained drug delivery device to treat severe uveitis
Ophthalmology
Intravitreal sustained-release cyclosporine in the treatment of experimental uveitis
Ophthalmology
A fluorescein angiographic study of cystoid macular edema
Am J Ophthalmol
Prophylaxis and therapy of aphakic cystoid macular edema
Surv Ophthalmol
Intraocular injection of crystalline cortisone as adjunctive treatment of diabetic macular edema
Am J Ophthalmol
Perifoveal microcirculation before and after vitrectomy for diabetic cystoid macular edema
Am J Ophthalmol
Efficacy of diclofenac eyedrops in preventing postoperative inflammation and long-term cystoid macular edema. Italian Diclofenac Study Group
J Cataract Refract Surg
Evaluation of grid pattern photocoagulation for macular edema in central vein occlusion. Central Vein Occlusion Study Group
Ophthalmology
Early photocoagulation for diabetic retinopathy. ETDRS report number 9. Early Treatment Diabetic Retinopathy Study Research Group
Ophthalmology
Techniques for scatter and local photocoagulation treatment of diabetic retinopathy: Early Treatment Diabetic Retinopathy Study Report no. 3. The Early Treatment Diabetic Retinopathy Study Research Group
Int Ophthalmol Clin
Treatment techniques and clinical guidelines for photocoagulation of diabetic macular edema. Early Treatment Diabetic Retinopathy Study Report Number 2. Early Treatment Diabetic Retinopathy Study Research Group
Ophthalmology
Photocoagulation for diabetic macular edema: Early Treatment Diabetic Retinopathy Study Report no. 4. The Early Treatment Diabetic Retinopathy Study Research Group
Int Ophthalmol Clin
Photocoagulation for diabetic macular edema. Early Treatment Diabetic Retinopathy Study report number 1. Early Treatment Diabetic Retinopathy Study research group
Arch Ophthalmol
Argon laser photocoagulation for macular edema in branch vein occlusion. The Branch Vein Occlusion Study Group
Am J Ophthalmol
Argon laser photocoagulation for macular edema in branch vein occlusion. The Branch Vein Occlusion Study Group
Am J Ophthalmol
Vascular endothelial growth factor-induced retinal permeability is mediated by protein kinase C in vivo and suppressed by an orally effective beta-isoform-selective inhibitor
Diabetes
Protein Kinase Cbeta selective inhibitor LY333531 ameliorates abnormal retinal hemodynamics in patients with diabetes
Diabetes
Suppression of retinal neovascularization in vivo by inhibition of vascular endothelial growth factor (VEGF) using soluble VEGF-receptor chimeric proteins
Proc Natl Acad Sci USA
Subthreshold (invisible) modified grid diode laser photocoagulation in diffuse diabetic macular edema (DDME)
Ophthalmic Surg Lasers
Hydraulic conductivity of fixed retinal tissue after sequential excimer laser ablation: barriers limiting fluid distribution and implications for cystoid macular edema
Arch Ophthalmol
Quantification of cystoid changes in diabetic maculopathy
Invest Ophthalmol Vis Sci
Laser treatment and the mechanism of edema reduction in branch retinal vein occlusion
Invest Ophthalmol Vis Sci
Clinico-pathological study of an organized plaque in exudative diabetic maculopathy
Can J Ophthalmol
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