Pseudoxanthoma elasticum (PXE) is an inherited metabolic disease with many systemic manifestations. Although the skin changes are striking, the eye and cardiovascular lesions can be most devastating to the patient.
Brown syndrome is defined as an ocular motility disorder, characterized by an inability to elevate the adducted eye actively or passively. The causes can be congenital or acquired, and the problem can be permanent or transient. Clinically, Brown syndrome is characterized by a significant limitation of elevation in the adducting position that occurs in the majority of cases and improved elevation is usually apparent in the midline, with generally normal elevation in abduction. Exodeviation (V pattern) can occur on elevation in the midline. Many patients are orthophoric in the primary position, although sometimes hypotropia can develop with a compensatory face turn towards the opposite eye. A positive forced duction test is usually the hallmark of Brown syndrome.