Visual Field Defects in Patients With Optic Nerve Head Drusen

Ana Rita Viana; Sara Pereira; Alberto Lemos; Rita Basto; Renato Correia Barbosa; Alexandre Reis da Silva

doi:10.7759/cureus.51317

Visual Field Defects in Patients With Optic Nerve Head Drusen

Cureus. 2023 Dec 30;15(12):e51317. doi: 10.7759/cureus.51317. eCollection 2023 Dec.

Authors

Ana Rita Viana¹, Sara Pereira¹, Alberto Lemos¹, Rita Basto¹, Renato Correia Barbosa¹, Alexandre Reis da Silva¹

Affiliation

¹ Ophthalmology Department, Hospital Pedro Hispano, Unidade Local de Saúde de Matosinhos, Matosinhos, PRT.

Abstract

Background Optic nerve head drusen (ONHD) are acellular deposits in the optic nerve head, whose pathophysiology remains not fully understood. Most patients with ONHD have visual field (VF) defects. This study aims to describe the VF defects observed in patients with ONHD and to compare the anatomical and functional impairment between visible and buried ONHD. Methods Patients with ONHD were retrospectively studied. The retinal nerve fiber layer (RNFL) average thickness and the ganglion cell complex (GCC) average thickness were collected from optical coherence tomography data. Visual field index (VFI), mean deviation (MD), and pattern standard deviation (PSD) were collected from 30-2 standard automated perimetry. An abnormal VF test was defined as having a Glaucoma Hemifield Test outside normal limits and/or a PSD with a p-value<5%. Eyes with superficial or buried ONHD based on visibility by slit-lamp ophthalmoscopy were compared. Results Sixty-six eyes of 36 patients were included in the study. The mean age was 39.6 ± 2.5 years. Forty-nine eyes (81.7%) presented a VF defect: concentric VF constriction in 19 (38.8%), arcuate scotoma in 16 (32.7%), enlarged blind spot in 9 (18.4%), unspecific VF defect in 8 (16.3%), and nasal step in 3 (6.1%). Thirty-four eyes (51.5%) had superficial ONHD and 32 eyes (48.5%) had buried ONHD. Patients with superficial ONHD were significantly older (p<0.001) and presented a significantly lower VFI (p=0.010), lower MD (p=0.002), higher PSD (p<0.001), thinner GCC (p<0.001), and thinner RNFL (p<0.001) than patients with buried ONHD. VF defects were present in 90.6% of eyes with superficial ONHD and 71.4% of eyes with buried ONHD (p=0.113). The type of VF defects differed between groups (p=0.020). Conclusions Functional and structural impairment is more evident in eyes with superficial ONHD, maybe because the presence of calcification leads to greater axonal damage. Buried ONHD is more prevalent in younger patients, progressing to a superficial location and becoming calcified with age.

Keywords: anatomical impairment; automated perimetry; functional impairment; optic nerve head drusen; optical coherence tomography; visual field.