Exfoliation Syndrome and Exfoliative Glaucoma 201Figure 1.Distribution of exfoliation material on the lens surface. A, central disc; B,
transition zone; C, peripheral zone.
Detection of XFM is difficult without pupil dilation, particularly because
in the early stages of XFS the amount of XFM is small and its distribution less
obvious. Clinically XFS is frequently unilateral: at the slit lamp it is detectable
only in one eye. However, XFS is always a systemic disease: even in
apparently unilateral cases, XFM is ultrastructurally detectable in both eyes
and in several extraocular tissues and organs [3,4,8]. In approximately 38% of
unilateral presentations, XFS becomes clinically detectable in the seemingly
uninvolved fellow eye in a decade [9]. Clinically XFS (and XFG) typically
appears after 60 years of age.
XFM is also frequently detectable on the pupil margin[10,11], the corneal
endothelium[12], the zonules and the anterior chamber angle where pigment
granules liberated from the iris tissue due to XFS are typically accumulated
and distributed along undulating lines on and anterior to the Schwalbe’s line
(Sampaolesi’ line) [3,4,11]. The loss of melanin granules results in the typical
“moth-eaten” appearance of the pupillary margin in XFS. The zonules holding