Fuchs' dystrophy
This occurs because the cornea is normally thicker in the morning; it retains fluids during sleep that evaporate in the tear film while we are awake. As the disease worsens, this swelling will remain constant and reduce vision throughout the day. Medical management includes topical hypertonic saline, the use of a hairdryer to dehydrate the precorneal tear film, and therapeutic soft contact lenses.Although doctors can often see early signs of Fuchs dystrophy in people in their 30s and 40s, the disease rarely affects vision until people reach their 50s and 60s. The condition was first described by Austrian Ernst Fuchs (1851-1930), after whom it is named. Fuchs’ endothelial dystrophy (FED) is a degenerative disorder of the corneal endothelium with accumulation of focal excrescences called guttae and thickening of Descemet’s membrane, leading to corneal edema and loss of vision. In FED, Descemet’s membrane is grossly thickened with accumulation of abnormal wide-spaced collagen and numerous guttae.
Progressive endothelial cell loss causes relative influx of aqueous humor into the cornea, leading to swelling (corneal stromal edema), which results in distorted vision. In using a hairdryer, the patient is instructed to hold a hairdryer at an arm s length or directed across the face, to dry out the epithelial blisters.
Eventually, the epithelium also becomes edematous, resulting in more severe visual impairment. Corneal endothelial cells are the major “pump” cells of the cornea to allow for stromal clarity.
DLEK and DSEK avoid the surgical complications of PKP such as wound dehiscence and infections and high postoperative astigmatism. Hence, patients with a history of Fuchs dystrophy may be at a greater risk of corneal edema after ocular surgery as they have fewer functioning endothelial cells. FED is classified into 4 stages, from early signs of guttae formation to end-stage subepithelial scarring.
A common scenario involves excessive corneal swelling or edema following cataract surgery or other types of ocular surgery. This could allow faster recovery for patients because of the ability to perform DSEK through very small (3 mm) sutureless incisions. Recently, endothelial keratoplasty has been further refined to Descemet Membrane Endothelial Keratoplasty (DMEK), in which only a donor Descemet membrane and its endothelium is transplanted.
Focal areas or blisters of epithelial edema ( bullae ) may be particularly painful. The inheritance of FED is autosomal dominant with genetic and environmental modifiers such as increased prevalence in the elderly and in females. These procedures, called posterior lamellar keratoplasty or endothelial keratoplasty, have been popularized as deep lamellar endothelial keratoplasty (DLEK) and Descemet’s stripping with endothelial keratoplasty (DSEK).
The National Eye Institute (NEI) is one of the United States federal government s National Institutes of Health. Information added was based on scientific reports in the scientific literature summarized on *http://www.niios.com/content.php?na=9#publications. Epithelial basement membrane dystrophy (OMIM 121820), called a corneal dystrophy but in reality this condition is not inherited in the majority of cases, representing a non-specific reaction to a variety of corneal insults. · Subepithelial mucinous corneal dystrophy · Meesmann juvenile epithelial corneal dystrophy (MECD, Stocker-Holt dystrophy, OMIM 122100) · Lisch epithelial dystrophy · Gelatinous drop-like corneal dystrophy eyelid: inflammation (Stye, Chalazion, Blepharitis) · Entropion · Ectropion · Lagophthalmos · Blepharochalasis · Ptosis · Blepharophimosis · Xanthelasma · eyelash (Trichiasis, Madarosis) lacrimal system: Dacryoadenitis · Epiphora · Dacryocystitis · Xerophthalmia orbit: Exophthalmos · Enophthalmos conjunctiva: Conjunctivitis (Allergic conjunctivitis) · Pterygium · Pinguecula · Subconjunctival hemorrhage Iritis · Uveitis (Intermediate uveitis) · Iridocyclitis · Hyphema · Rubeosis iridis · Persistent pupillary membrane · Iridodialysis · Synechia Optic neuritis · Papilledema · Optic atrophy · Leber s hereditary optic neuropathy · Dominant optic atrophy · Optic disc drusen · Glaucoma · Toxic and nutritional optic neuropathy · Anterior ischemic optic neuropathy Other strabismus: Esotropia/Exotropia · Hypertropia · Heterophoria (Esophoria, Exophoria) · Brown s syndrome · Duane syndrome Other binocular: Conjugate gaze palsy · Convergence insufficiency · Internuclear ophthalmoplegia · One and a half syndrome COL1: Osteogenesis imperfecta · Ehlers-Danlos syndrome, types 1,2,&7 COL2: Hypochondrogenesis · Achondrogenesis type 2 · Stickler syndrome · Marshall syndrome · Spondyloepiphyseal dysplasia congenita (see also C2/11) COL3: Ehlers-Danlos syndrome, types 3&4 (Sack-Barabas syndrome) COL4: Alport syndrome COL5: Ehlers-Danlos syndrome, types 1&2 COL6: Bethlem myopathy · Ullrich congenital muscular dystrophy COL7: Epidermolysis bullosa dystrophica COL8: Fuchs dystrophy COL9: Multiple epiphyseal dysplasia COL10: Schmid metaphyseal chondrodysplasia COL11: Weissenbacher-Zweymüller syndrome · Otospondylomegaepiphyseal dysplasia (see also C2/11) COL17: Bullous pemphigoid . Mutations in collagen VIII, a major component of Descemet’s membrane secreted by endothelial cells, have been linked to the early-onset FED. At first, a person with Fuchs dystrophy will awaken with blurred vision that will gradually clear during the day.
in The Netherlands. With DMEK, 90% of cases achieve a best spectacle corrected visual acuity 20/40 or better, and 60% of cases 20/25 or better within 1–3 months. More speculative future directions in the treatment of FED include in vitro expansion of human corneal endothelial cells for transplantation, artificial corneas and genetic modification. Anecdotally, botulinum toxin type A given to the periocular tissues for a patient with blepharospasm and hemifacial spasm resulted in dramatic and immediate improvement in vision, lasting about 2–3 months after each quarterly treatment. This article was originally based on content from the National Eye Institute web page Facts About The Cornea and Corneal Disease.
Corneal endothelial cells in end-stage FED are reduced in number and appear attenuated, causing progressive stromal edema. Definitive treatment, however, (especially with increased corneal edema) is surgical in the form of corneal transplantation, or penetrating keratoplasty (PKP). Since 1998, new surgical modalities in the treatment of FED have been developed by Melles et al.
Improved surgical instrumentation for DSEK, such as a DSEK graft injector will become available shortly (2008). This can be done two or three times a day.
Endothelial cell loss may be aggravated or accelerated by intraocular trauma or surgery. Fuchs dystrophy, also known as Fuchs endothelial dystrophy, is a slowly progressing corneal disease that usually affects both eyes and is slightly more common in women than in men.
Since 2004, DSEK has become the dominant procedure because it is technically much easier for the surgeon compared to DLEK or PKP. Diagnosis is made by biomicroscopic examination; other modalities, such as corneal pachymetry, confocal biomicroscopy, and specular microscopy can be used in conjunction. Exact pathogenesis is unknown but factors include endothelial cell apoptosis, sex hormones, inflammation, and aqueous humor flow and composition.
