The development of microneovascular changes in the iris in pseudoexfoliation of the lens capsule.

Iris angiography was performed in 25 cases with unilateral pseudoexfoliation of the lens capsule (PXF) (including two which later became bilateral) to study the development of the microneovascular changes which accompany PXF. Sixteen patients had raised intraocular pressure (IOP) and nine had no rise in IOP in the affected eye. Twenty-two patients had no rise in IOP in the unaffected eye, whereas three had a rise in IOP in the unaffected eye as well as the affected eye. The great majority of unaffected eyes showed no abnormality on iris angiography or only mild hypoperfusion of the iris. Mild evidence of microneovascularization was present in only six unaffected eyes. The 25 affected eyes showed the signs of microneovascularization and hypoperfusion of the iris characteristic of PXF unrelated to the presence or absence of raised IOP. Microneovascularization developed and iris perfusion diminished after the clinical appearance of PXF in two previously unaffected eyes. The authors hypothesize that although hypoperfusion may contribute to the formation of PXF, hypoperfusion is not the primary cause of the condition and may not be necessary for its production. Rather, hypoperfusion occurs as a reaction to the development of PXF.