2025 American Academy of Neurology Abstract Website

Objective:

This study aimed to compare visual field threshold value changes in Normal Pressure Hydrocephalus (NPH) patients with and without Primary Open-Angle Glaucoma (POAG).

Background:

While NPH and POAG both affect visual function, their combined impact remains unclear. Recent retrospective studies have suggested a significant glaucoma risk in NPH patients.

Design/Methods:

We conducted a retrospective study using OPUS, a system developed at Mayo Clinic's Department of Ophthalmology. The study included age-matched patients with at least two reliable visual field tests for both eyes. We compared 59 NPH+POAG patients (average follow-up: 7.7 years) with 235 NPH patients without POAG (average follow-up: 1.7 years). Visual field data was retrieved in DICOM format, converted to PDF, and analyzed using custom software with Optical Character Recognition (OCR) to extract threshold values. Changes in visual field threshold values between the first and last tests were compared between groups.

Results:

The mean visual field threshold for the NPH+POAG group was 22.75dB at the first test and 20.4dB at the last test, while the NPH-only group showed 24.87dB and 24.85dB, respectively. The difference in visual field thresholds was -2.35dB for the NPH+POAG group and -0.02dB for the NPH-only group. An independent samples t-test revealed a significant difference between the two groups (p=0.005). The NPH-only group demonstrated less change overall, contrasting with the more pronounced deterioration in the NPH+POAG group.

Conclusions:

NPH patients with concomitant POAG exhibited significantly greater visual field deterioration compared to NPH patients without POAG. Interestingly, NPH patients without POAG showed stability in their visual fields. This finding suggests that POAG presence in NPH patients may result in visual field loss, highlighting the importance of careful monitoring and management in this patient population.