Exfoliation Glaucoma

Clinical Characteristics
Ocular Features: 

Whitish flakes resembling dandruff appear on the anterior lens capsule during midlife, often accompanied by pigment.  It is a progressive disorder in all aspects and once established does not regress.  The condition is often asymmetrical and even unilateral, at least in some stages.  This fibrillar material is deposited throughout the anterior chamber including the trabecular meshwork where it blocks the outflow mechanism leading to glaucoma.  The latter is often severe and difficult to control.  It is claimed that the risk of glaucoma is 6 times greater among such patients compared with individuals who do not have exfoliation.  Cataract prevalence is higher among patients with exfoliation and those with cataracts have a higher prevalence of exfoliation.  Dilation is often difficult in such patients and operative complications such as capsular rupture, lens mobility, and vitreous loss are greater.  Posterior synechiae are more frequent in exfoliation patients.  Pupillary block and angle closure glaucoma are additional glaucoma risks.

The majority of evidence suggests that the source of the exfoliation material is the extracellular matrix of ocular structures including the lens epithelium, iris pigment epithelium and the non-pigmented ciliary epithelium.  The exact composition of the material, however, has not been established.

Systemic Features: 

Some consider this to be a systemic disease as well and have associated it with widespread cardiovascular complications, including hypertension, stroke, myocardial infarctions and transient ischemic attacks.  Fibrillar material has been identified in autopsy material among many visceral organs including heart, kidney, liver, and CNS meninges.  Physiologic or etiologic connections, however, have not been established.  The mortality rate among patients with exfoliation syndrome does not appear to be increased and it is currently not recommended that all individuals with ocular pseudoexfoliation undergo general systemic evaluations.

Genetics

This disorder has an ethnic population distribution, an important indication of its genetic basis.  It occurs with high frequency in Scandinavians, Amerindians, Greeks and selective black populations in Africa.  It is not seen in Eskimos. 

There is evidence that mutations in LOXL1 (15q22) confer susceptibility to exfoliation syndrome.  However, a specific mutational basis and transmission pattern has yet to be determined.  Available evidence is most suggestive of autosomal dominant inheritance but a multifactorial or susceptibility mechanism cannot be ruled out.

Treatment
Treatment Options: 

No treatment for the exfoliation is available.  Cataract extraction may result in reduction of diffused extracellular material and it has been reported that the intraocular pressure is easier to control.  The risk of intraoperative complications is high, however, and surgical caution must be exercised.

References
Article Title: 

Common sequence variants in the LOXL1 gene confer susceptibility to exfoliation glaucoma

Thorleifsson G, Magnusson KP, Sulem P, Walters GB, Gudbjartsson DF, Stefansson H, Jonsson T, Jonasdottir A, Jonasdottir A, Stefansdottir G, Masson G, Hardarson GA, Petursson H, Arnarsson A, Motallebipour M, Wallerman O, Wadelius C, Gulcher JR, Thorsteinsdottir U, Kong A, Jonasson F, Stefansson K. Common sequence variants in the LOXL1 gene confer susceptibility to exfoliation glaucoma. Science. 2007 Sep 7;317(5843):1397-400.

PubMed ID: 
17690259

Exfoliation syndrome

Ritch R, Schlotzer-Schrehardt U. Exfoliation syndrome. Surv Ophthalmol. 2001 Jan-Feb;45(4):265-315. Review.

PubMed ID: 
11166342

References

Thorleifsson G, Magnusson KP, Sulem P, Walters GB, Gudbjartsson DF, Stefansson H, Jonsson T, Jonasdottir A, Jonasdottir A, Stefansdottir G, Masson G, Hardarson GA, Petursson H, Arnarsson A, Motallebipour M, Wallerman O, Wadelius C, Gulcher JR, Thorsteinsdottir U, Kong A, Jonasson F, Stefansson K. Common sequence variants in the LOXL1 gene confer susceptibility to exfoliation glaucoma. Science. 2007 Sep 7;317(5843):1397-400.

PubMedID: 17690259

Schlotzer-Schrehardt U, Naumann GO. Ocular and systemic pseudoexfoliation syndrome. Am J Ophthalmol. 2006 May;141(5):921-937. Review.

PubMedID: 16678509

Ritch R, Schlotzer-Schrehardt U. Exfoliation syndrome. Surv Ophthalmol. 2001 Jan-Feb;45(4):265-315. Review.

PubMedID: 11166342