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Retinal thinning in phenylketonuria and Gaucher disease type 3
Susanne Hopf1, Alexander K Schuster2, Julia B Hennermann3
1Department of Ophthalmology, University Medical Center of the Johannes Gutenberg-University Mainz, Langenbeckstraße 1, 55131, Mainz, Germany. hopf101@gmail.com.
Summary
Retinal thinning in the nerve fiber, ganglion cell, and inner plexiform layers occurs in phenylketonuria (PKU) and Gaucher disease type 3 (GD3). These changes may relate to dopamine levels but are not reliable biomarkers for GD3 severity.
Area of Science:
- Neuro-ophthalmology
- Neurodegenerative diseases
- Metabolic disorders
Background:
- Inherited metabolic diseases (IMDs) with neurodegeneration can affect the retina.
- Retinal alterations in phenylketonuria (PKU) and Gaucher disease type 3 (GD3) are not well understood.
- These diseases involve potential dopaminergic depletion, impacting retinal function.
Purpose of the Study:
- To investigate retinal thickness in the ganglion cell complex (GCC) of patients with PKU and GD3.
- Specifically analyze the nerve fiber layer (NFL), ganglion cell layer (GCL), and inner plexiform layer (IPL).
- Utilize spectral-domain optical coherence tomography (SD-OCT) for precise measurements.
Main Methods:
- SD-OCT macular and peripapillary scans were performed on 19 PKU patients, 15 GD3 patients, and 93 controls.
- Linear mixed models adjusted for age, sex, and spherical equivalent were employed.
- Correlations between retinal layer thickness and clinical/laboratory parameters were assessed.
Main Results:
- PKU showed thinning in macular inner and outer rings, sparing the fovea. GD3 exhibited thinning across all macular subfields.
- Significant thinning was observed in the NFL, GCL, and IPL in both diseases.
- The outer plexiform layer (OPL) was thickened in both PKU and GD3 patients. GCL and IPL thinning in PKU correlated with serum tyrosine levels.
Conclusions:
- Both PKU and GD3 demonstrate retinal thinning in the NFL, GCL, and IPL, with OPL thickening.
- Reduced retinal dopamine concentrations may contribute to these observed changes.
- Current retinal measurements do not serve as reliable biomarkers for GD3 disease severity.
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