Comparison of Visual Field Measurement with Heidelberg Edge Perimeter and Humphrey Visual Field Analyzer in Patients with Ocular Hypertension.

BACKGROUND: Glaucoma is a group of eye diseases which result in damage to the optic nerve and vision loss. The most important examination in glaucoma patients is visual field assessment. One of the newer perimeters is Heidelberg Edge Perimeter (HEP).

OBJECTIVES: The aim of the study was to compare visual field measurements made with Humphrey II 740 Visual Field (Carl Zeiss Meditec) and Heidelberg Edge Perimeter (HEP) (Heidelberg Engineering). FDF stimulus (flicker defined form) in HEP stimulates magnocellular retinal cells, which are the first to be damaged in the early stage of glaucoma. Even a small loss of magnocellular cells may influence HEP visual field.

MATERIAL AND METHODS: The observed group consisted of 45 patients (82 eyes), age 60 ± 9.8 years, glaucoma suspects, not treated pharmacologically or surgically before, with intraocular pressure ≥ 22 mm Hg. Visual field values were measured with two different devices: Humphrey II 740 Visual Field (Carl Zeiss Meditec, Jena, Germany) and Heidelberg Edge Perimeter (Heidelberg Engineering, Heidelberg, Germany). The patients were divided into two groups: Group 1 - tested with SITA Standard program on Humphrey perimeter and ASTA Standard HEP, and Group 2 - tested with SITA Fast program on Humphrey perimeter and ASTA Standard on HEP.

RESULTS: Few positive ΔMD results (ΔMD = MD HEP - MD HUM) were obtained in Groups 1 and 2, which means that the deviation value on the HEP perimeter was only slightly higher than the mean deviation value on Humphrey. Therefore, one can conclude that HEP perimeter may detect visual field defects with greater precision. The visual field measurements between ASTA Standard on HEP and SITA Standard on Humphrey as well as ASTA Standard on HEP and SITA Fast on Humphrey are not equal: MD values on HEP perimeter are lower than MD on Humphrey, which can mean that HEP perimeter provides more precise results and shows even early visual field lesions.

CONCLUSIONS: HEP perimeter measures visual field defects with greater precision so it should be taken into consideration for earlier glaucoma detection in routine ophthalmological diagnosis.