Influence of Corneal Opacity on Intraocular Pressure Assessment in Patients with Lysosomal Storage Diseases

Joanna Wasielica-Poslednik; Giuseppe Politino; Irene Schmidtmann; Katrin Lorenz; Katharina Bell; Norbert Pfeiffer; Susanne Pitz

doi:10.1371/journal.pone.0168698

Influence of Corneal Opacity on Intraocular Pressure Assessment in Patients with Lysosomal Storage Diseases

PLoS One. 2017 Jan 12;12(1):e0168698. doi: 10.1371/journal.pone.0168698. eCollection 2017.

Authors

Joanna Wasielica-Poslednik¹, Giuseppe Politino¹, Irene Schmidtmann², Katrin Lorenz¹, Katharina Bell¹, Norbert Pfeiffer¹, Susanne Pitz¹

Affiliations

¹ Department of Ophthalmology, University Medical Center, Johannes Gutenberg- University Mainz, Germany.
² Institute for Medical Biostatistics, Epidemiology and Informatics (IMBEI), University Medical Center, Johannes Gutenberg University Mainz, Germany.

Abstract

Aims: To investigate an influence of mucopolysaccharidosis (MPS)- and Morbus Fabry-associated corneal opacities on intraocular pressure (IOP) measurements and to evaluate the concordance of the different tonometry methods.

Methods: 25 MPS patients with or without corneal clouding, 25 Fabry patients with cornea verticillata ≥ grade 2 and 25 healthy age matched controls were prospectively included into this study. Outcome measures: Goldmann applanation tonometry (GAT); palpatory assessment of IOP; Goldmann-correlated intraocular pressure (IOPg), corneal-compensated intraocular pressure (IOPcc), corneal resistance factor (CRF) and corneal hysteresis (CH) assessed by Ocular Response Analyzer (ORA); central corneal thickness (CCT) and density assessed with Pentacam. Statistical analysis was performed using linear mixed effect models and Spearman correlation coefficients. The concordance between tonometry methods was assessed using Bland-Altman analysis.

Results: There was no relevant difference between study groups regarding median GAT, IOPg, IOPcc and CCT measurements. The limits of agreement between GAT and IOPcc/IOPg/palpatory IOP in MPS were: [-11.7 to 12.1mmHg], [-8.6 to 15.5 mmHg] and [- 5.4 to 10.1 mmHg] respectively. Limits of agreement were less wide in healthy subjects and Fabry patients. Palpatory IOP was higher in MPS than in healthy controls and Fabry patients. Corneal opacity correlated more strongly with GAT, IOPg, CH, CRF, CCT and corneal density in MPS (r = 0.4, 0.5, 0.5, 0.7, 0.6, 0.6 respectively) than in Fabry patients (r = 0.3, 0.2, -0.03, 0.1, 0.3, -0.2 respectively). In contrast, IOPcc revealed less correlation with corneal opacity than GAT in MPS (r = 0.2 vs. 0.4).

Conclusions: ORA and GAT render less comparable IOP-values in patients suffering from MPS-associated corneal opacity in comparison to Fabry and healthy controls. The IOP seems to be overestimated in opaque MPS-affected corneas. GAT, IOPg and biomechanical parameters of the cornea correlate more strongly with the corneal clouding than IOPcc in MPS patients.

Trial registration: ClinicalTrials.gov NCT01695161.

Publication types

Clinical Trial
Observational Study

MeSH terms

Adolescent
Adult
Aged
Cornea* / pathology
Cornea* / physiopathology
Corneal Opacity* / etiology
Corneal Opacity* / pathology
Corneal Opacity* / physiopathology
Female
Humans
Intraocular Pressure*
Male
Middle Aged
Mucopolysaccharidoses* / complications
Mucopolysaccharidoses* / pathology
Mucopolysaccharidoses* / physiopathology

Associated data

ClinicalTrials.gov/NCT01695161

Grants and funding

Prof. Susanne Pitz was supported by Genzyme (US) and Shire. The funds were used for the acquisition of the Ocular Response Analyzer. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.