Heidelberg Edge Perimetry (HEP) Detecting Glaucomatous Visual Field Defects (HEP)

Validation and Reproducibility of the Heidelberg Edge Perimeter in the Detection of Visual Field Defects in Glaucomatous Patients

The purpose of this study is to compare standard automated perimetry (SAP) using the Heidelberg Edge Perimeter (HEP) to the Octopus Visual Field (OVF) analyzer and determine test-retest reliability of both parameters in detecting glaucomatous visual field losses. This study will also investigate novel imaging parameters of the optic nerve head and new automated structure-function reports.

Each participant undergo the following tests: Standard ophthalmic examination (usual care): Best-corrected visual acuity, biomicroscopy (look at front of eye), intraocular pressure (IOP) using Goldman applanation tonometry, central corneal thickness measurement and fundoscopy (look at back of eye). Octopus Visual Field (OVF) Analyzer using G-top strategy recording mean deviation (MD) and pattern standard deviation (PSD). Heidelberg Edge Perimeter (HEP) standard automated perimetry (SAP) using advanced staircase thresholding algorithm (ASTA). Spectralis optical coherence tomography (OCT) using glaucoma module premium edition (GMPE) software to measure minimum rim width (MRW) and retinal nerve fiber layer (RNFL) thickness in 6 sectors (superior nasal, superior temporal, inferior nasal, inferior temporal, nasal and temporal) in the retina. Order of HEP SAP III and OVF, and order of the eye tested (right vs. left) if both eyes of patients meet inclusion criteria will be randomized. Patients with glaucoma will be randomly chosen and asked to return in 3 to 6 months for repeat HEP and OVF testing.

Subjects with glaucoma were recruited based on characteristic glaucomatous disc damage and visual field changes. They will perform visual field with Heidelberg Edge Perimeter and Octopus visual field. Optical Coherence Tomography will image the retinal nerve fiber layer.

Subjects that do not have glaucoma and are recruited for testing will perform visual field with Heidelberg Edge Perimeter and Octopus visual field. Optical Coherence Tomography will image the retinal nerve fiber layer.

Pearson's correlation coefficient between Heidelberg Edge Perimeter (HEP) and Octopus Visual Field (OVF) Mean Deviation (MD) for glaucoma patients and controls to determine if HEP can detect glaucoma as well as OVF. The closer the values of both parameters for both machines, the better comparable the two machines are to each other in detecting glaucoma.

A subgroup of participants were randomly selected to return at 3 and 6 months for repeat testing. Not all eyes were included. Repeatability of optical coherence tomography (OCT) to consistently detect minimum rim width (MRW) global thickness will be assessed by Pearson's interclass correlation coefficients (ICC). A larger ICC indicates measurements have greater repeatability. Greater than 0.75 indicated excellent repeatability; 0.40 to 0.75 indicated fair to good, and less than 0.40 indicated poor reliability.

Heidelberg Edge Perimeter (HEP) Visual Field (VF) and spectral domain optical coherence tomography (SD OCT) printouts from only the glaucoma subgroup were assessed. Retinal Nerve Fiber Layer (RNFL) and Minimum Rim Width (MRW) from SD OCT and HEP VF automated reports were compared to the clinical interpretations by 3 glaucoma specialists.

Inclusion Criteria: Age > 18 years. Best corrected visual acuity of 20/40 or better in the tested eye. Spherical refraction within ±5.0 D, and cylinder correction within ±3.0 D. History of glaucoma, defined as: Characteristic of glaucomatous disc damage: (local narrowing, notching, or absence of the neuroretinal rim in the absence of disc pallor elsewhere). Exclusion Criteria: Any condition preventing adequate examination of the pupil or visual field testing (e.g. ptosis, dense corneal opacities or lens opacities); Active infection of the anterior or posterior segments of the eye; Any intraocular surgical or laser procedure within the previous 4 weeks; Participants taking a medication known to affect visual field sensitivity, a coexisting intraocular disease affecting visual field, or a problem other than glaucoma affecting color vision will be excluded.

Cui QN, Fudemberg SJ, Resende AF, Vu TA, Zhou C, Rahmatnejad K, Hark LA, Myers JS, Katz LJ, Waisbourd M. Validation of the structure-function correlation report from the heidelberg edge perimeter and spectral-domain optical coherence tomography. Int Ophthalmol. 2019 Mar;39(3):533-540. doi: 10.1007/s10792-018-0836-z. Epub 2018 Feb 2.