Evaluation of Regional Brain Perfusion in Patients with Pseudoexfoliation Syndrome

Abstract

Pseudoexfoliation syndrome (PES) is characterised by the accumulation of abnormal extracellular fibrillar material in ocular tissue, which develops with ageing, and can lead to ocular complications, including glaucoma, cataract, zonular damage, and keratopathy. It has been shown that extraocular accumulation of pseudoexfoliation matter can occur in tissues such as the heart, lung, liver, kidney, cerebral meninges, aorta, and adventitia layer of cerebral arteries. Acute vascular complications are seen commonly with the involvement of the systemic vasculature. Pseudoexfoliation syndrome has also been reported in dementia and stroke patients. In this study, the authors aimed to evaluate regional brain perfusion in pseudoexfoliation syndrome patients. Twenty-four patients with PES with glaucoma (14 female, 10 male) and a control group of 19 healthy volunteers (10 female, 9 male) were included in the study. There was no cerebrovascular or psychiatric complaint in the patient or control group, and all subjects were right-handed. Brain perfusion single-photon emission computed tomography (SPECT) images were taken by low-energy general purpose collimator of a single-headed gamma camera after intravenous injection of 25 mCi technetium-99m-hexamethylpropylene amine oxime (Tc99m-HMPAO). To obtain the corticocerebellar ratio by semiquantitative analysis, 3 × 3 pixel regions of interest were drawn on transaxial sections, and the counts of frontal, temporal, parietal, and occipital regions were divided by the counts of the cerebellar region bilaterally. The mean ages of the PES and control groups were 67.83 ± 9.03 and 64.52 ± 6.88 years, respectively. The mean corticocerebellar ratio in PES was decreased in frontal, temporal, parietal, and occipital lobes bilaterally (p value interval min: 0.001, max: 0.049). The results showed that there was a decrease in frontal, temporal, parietal, and occipital cortices perfusion in PES patients bilaterally.

Keywords::

• pseudoexfoliation syndrome
• regional brain perfusion
• Tc99m-HMPAO SPECT

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.