Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Case Reports
. 2012 Jan;3(1):104-12.
doi: 10.1159/000337492. Epub 2012 Mar 26.

Visual Dysfunction of Type I and VI Mucopolysaccharidosis Patients Evaluated with Visual Evoked Cortical Potential

Bruno Duarte Gomes  1 , Givago da Silva Souza, Gustavo Monteiro Viana, Isabel Cristina Neves de Souza, Patricia do Socorro Queiroz Feio, Ida Vanessa Doederlein Schwartz, Diane Ruschel Marinho, Manoel da Silva Filho, Roberto Giugliani, Luiz Carlos de Lima Silveira, Luiz Carlos Santana da Silva
Affiliations
Case Reports

Visual Dysfunction of Type I and VI Mucopolysaccharidosis Patients Evaluated with Visual Evoked Cortical Potential

Bruno Duarte Gomes et al. Case Rep Ophthalmol. 2012 Jan.

Abstract

Purpose: To evaluate the visual system of patients suffering from type I or VI mucopolysaccharidosis (MPS) by recording the visual evoked cortical potential (VECP).

Methods: Two patients with MPS VI and 2 patients with MPS I were tested before and after enzyme replacement therapy (ERT). A control group of 20 subjects was tested for statistical comparison. VECP was elicited by monocular stimulation with 1-Hz phase-reversal checkerboard patterns at 0.5 and 2 cycles per degree and with 16° of visual field. In all patients, both eyes were tested. VECP amplitude and latency were measured and compared with tolerance limits obtained from controls.

Results: MPS I and VI patients have a severe visual impairment that can be quantified by measuring VECPs. Even after several weeks of ERT, the visual impairment remained unaltered, indicating that the treatment had no significant influence on the visual conditions of MPS patients. Visual responses to high spatial frequencies were more deeply impaired than responses to low spatial frequencies. This can be explained by the kind of damage in the visual system that preferentially targets the eye optics.

Conclusion: VECPs can be used to monitor the degree of visual impairment of MPS patients and to check ERT efficacy.

Keywords: Enzyme replacement therapy; Glycosaminoglycans; Mucopolysaccharidosis; Visual evoked cortical potential.

PubMed Disclaimer

Figures

Fig. 1
Fig. 1
VECPs from MPS patients at 0.5 and 2 cpd. a MPS I patient 3. b MPS I patient 4. None of the subjects were on ERT at the moment of recordings. Dotted lines represent the grand mean recordings from the control group. Bold and gray lines represent recordings obtained by stimulating the patients’ right or left eye, respectively.
Fig. 2
Fig. 2
VECPs from MPS patients. a, b MPS VI patients 1 and 2, respectively, 30 days after the unique enzyme reposition given to these subjects. c, d MPS I patient 3 1 day after the second enzyme reposition (a) and 68 days after the fourth reposition (b) at the two spatial frequencies studied, 0.5 and 2 cpd. Dotted lines represent the grand mean recordings from the control group. Bold and gray lines represent recordings obtained by stimulating the patients’ right and left eye, respectively.
See this image and copyright information in PMC

References

    1. Muenzer J. The mucopolysaccharidoses: a heterogeneous group of disorders with variable pediatric presentations. J Pediatr. 2004;144:27–34. - PubMed
    1. Cantor LB, Disseler JA, Wilson FM. Glaucoma in the Maroteaux-Lamy syndrome. Am J Ophthalmol. 1989;108:426–430. - PubMed
    1. Collins ML, Traboulsi EI, Maumenee IH. Optic nerve head swelling and optic atrophy in the systemic mucopolysaccharidoses. Ophthalmol. 1990;97:1445–1449. - PubMed
    1. Casanova FH, Adan CB, Consuelo BD, Allemann N, de Freitas D. Findings in the anterior segment on ultrasound biomicroscopy in Maroteaux-Lamy syndrome. Cornea. 2001;20:333–338. - PubMed
    1. Ashworth JL, Biswas S, Wraith E, Lloyd IC. Mucopolysaccharidoses and the eye. Sur Ophthalmol. 2006;51:1–17. - PubMed

Publication types