BASICS
DESCRIPTION
An acquired and usually unilateral condition affecting young and middle-aged women. The condition causes various degrees of iris abnormalities, corneal edema, and glaucoma in affected individuals. The etiology is unknown, but is thought to be due to a viral infection. It affects all races. The hallmark of the condition is an abnormal corneal endothelium, which advances onto the anterior chamber angle and iris.
Pediatric Considerations
It rarely affects children. A case of an 11-year-old girl with ICE syndrome and glaucoma was reported (1).
Geriatric Considerations
Older patients may have limitation in vision in the affected eye due to corneal disease and/or glaucomatous optic nerve damage.
Pregnancy Considerations
Glaucoma medications may need to be adjusted during pregnancy and nursing.
EPIDEMIOLOGY
ICE syndrome is a very rare condition with no known genetic risk factors.
GENERAL PREVENTION
There is no known preventive measure ICE syndrome.
ETIOLOGY
Thought to be due to a viral infection. In one study 5 out of 9 corneal specimens were positive for herpes simplex virus (HSV) DNA in the corneal endothelium. The specimens were negative for herpes zoster virus or Epstein–Barr virus DNA (2).
COMMONLY ASSOCIATED CONDITIONS
• There are 3 variants that have slightly different presentations and courses. All 3 variants are associated with corneal disease and glaucoma.
• Essential or progressive iris atrophy is notable for corectopia (distorted pupil) or pseudopolycoria (a “second” pupil). Marked iris atrophy is a hallmark of this variant. Severe anterior segment abnormalities may include extensive peripheral anterior synechiae (PAS). PAS formation is progressive, leading to angle closure and frequently elevated intraocular pressure (IOP). Secondary angle-closure glaucoma is present in at least 50% of individuals.
• Iris nevus syndrome (Cogan Reese) is notable for the presence of a large nevus covering a large part of the iris or multiple iris nodules. Specimens from eyes enucleated for presumed malignancy demonstrated iris tissue in these nevi.
• Chandler’s syndrome is notable for a corneal endothelium with a characteristic “hammered silver” appearance. Chandler’s syndrome variant has a lower incidence of glaucoma and a higher incidence of corneal edema due to dysfunction of normal endothelial function.
DIAGNOSIS
HISTORY
Signs and symptoms:
• Almost always has a unilateral presentation
• Decreased vision due to corneal edema, which is frequently worse in the morning upon awakening
• Pain is usually due to corneal edema, but may be from elevated IOP later on in the course of the disease.
• Iris abnormalities noticed by patient or family and friends
• Decreased visual function due to glaucoma is present in advanced disease.
PHYSICAL EXAM
Slit lamp exam can demonstrate corneal edema and abnormal corneal endothelial appearance. Areas of abnormal corneal endothelium may be seen in the fellow eye. Iris atrophy and pupillary irregularity or decentration are hallmarks of progressive iris atrophy. Gonioscopy can reveal complete angle closure, especially in essential iris atrophy.
DIAGNOSTIC TESTS & INTERPRETATION
• Visual acuity may be reduced in the affected eye and may fluctuate with varying degrees of corneal edema.
• Visual field may be abnormal if there is co-existing glaucomatous optic neuropathy.
Imaging
• Optic nerve imaging can be helpful in establishing diagnosis of glaucoma or assisting in detection of glaucoma progression. Imaging devices include optic nerve photography, optical coherence tomography (OCT), confocal scanning laser ophthalmoscopy (Heidelberg Retina Tomograph – HRT), and scanning laser polarimetry (GDx).
• Corneal disease is mostly followed clinically, but specular microscopy can demonstrate characteristic endothelial cell abnormality with variability in cell size and shape as well as loss of the normal clear hexagonal margins.
• Pachymetry can be useful to quantify corneal thickening.
DIFFERENTIAL DIAGNOSIS
• Fuch’s dystrophy may have a similar corneal appearance, but with no anterior chamber abnormalities.
• PPMD—may appear similar, but is familial and bilateral
• Axenfeld Riegers is congenital and bilateral and may have systemic findings, such as dental abnormalities.
• Iris melanomas can appear similar to pure Cogan–Reese syndrome.
TREATMENT
ADDITIONAL TREATMENT
General Measures
• Corneal edema can be treated with hypertonic saline drops or ointment (sodium chloride solution or ointment 5%).
• Elevated IOP and glaucoma can be treated with anti-glaucoma drops.
• Laser trabeculoplasty is not usually beneficial in this type of chronic angle-closure glaucoma.
• Laser peripheral iridotomy does not halt the progression of progressive angle closure that is a hallmark of this condition.
SURGERY/OTHER PROCEDURES
• Cataract surgery can be complicated by poor papillary dilation and the presence of an ICE membrane over the anterior capsule.
• Corneal transplants are performed for chronically edematous and hazy corneas. Newer partial-thickness corneal transplant procedures may reduce the incidence of rejection. Descemet Stripping Automated Endothelial Keratoplasty (DSAEK) involves Descemet’s and endothelial membrane transplant.
• Iris reconstruction surgery for improved cosmetic appearance or to ameliorate glare can be undertaken alone or at the time of cataract surgery. The iris tissue is often friable and difficult to suture. Artificial iris implantation can be useful (3).
• Glaucoma in ICE syndrome may be more severe and refractory to surgical management. Trabeculectomy may fail more frequently, and this is thought to be partially due to growth of abnormal corneal endothelium over the internal scleral ostium. Trabeculectomy in patients with Chandler’s syndrome may be more successful than in the other variants.
• Trabeculectomy may be more successful if performed with an anti-metabolite such as mitomycin C
• Glaucoma drainage implants (tube shunts) may be more successful than trabeculectomy as they may be less likely to be blocked with an endothelial membrane (4).
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
• Affected individuals should be followed up periodically for routine eye care. Mild cases without glaucoma may be seen yearly.
• Monitoring for development of glaucoma includes evaluation of optic nerve appearance with either direct or indirect ophthalmoscopy. Visual field testing and optic nerve imaging may also be appropriate.
• Individuals with glaucoma or corneal disease may need more frequent monitoring
• Corneal decompensation and glaucoma may require sub-specialty referral.
PROGNOSIS
• Visual prognosis is mostly related to severity of glaucoma but may be affected by success in restoration of corneal clarity.
• Complications from cataract surgery can also affect visual prognosis.
• Visual prognosis is generally more poor for individuals who reject multiple corneal transplants.
• Irregular refractive errors after corneal surgery may require use of specialty contact lenses.
REFERENCES
1. Salim S, Shields MB, Walton D. Iridocorneal endothelial syndrome in a child. J Pediatr Ophthalmol Strabismus 2006;43:308–310.
2. Alvarado JA, Underwood JL, Green WR, et al. Detection of herpes simplex viral DNA in the iridocorneal endothelial syndrome. Arch Ophthalmol 1994;112:1601–1609.
3. Khng C, Snyder ME. Iris reconstruction with a multipiece endocapsular prosthesis in iridocorneal endothelial syndrome. J Cataract Refract Surg 2005;31:2051–2054.
4. Doe EA, Budenz DL, Gedde SJ, Imami NR. Long-term surgical outcomes of patients with glaucoma secondary to the iridocorneal endothelial syndrome. Ophthalmology 2001;108:1789–1795.