Ophthalmoscopic and video OCT methods to detect spontaneous venous pulsation in individuals with apparently normal intracranial pressure: the rebirth of the SVP?
Abstract
Purpose
To compare the efficiency of high magnification binocular indirect ophthalmoscopy and direct ophthalmoscopy in detecting the spontaneous venous pulsation (SVP) at the optic nerve head, and to demonstrate the utility of video optical coherence in detecting the phenomenon in patients with normal intracranial pressure.
Methods
The SVP of the right eye of 54 consecutive clinic patients presenting without neuro-ophthalmic symptoms and with BMIs under 30 were dilated and examined by one ophthalmologist using a 66D handheld Volk lens, then examined by a second blinded ophthalmologist using direct ophthalmoscopy. Immediately the patient was assessed by a third blinded ophthalmologist via vOCT for the presence or absence of SVP.
Results
The population included 20 males and 34 females and were corrected for VA (M 0.127 LogMAR, SD 0.22, SE 0.036), IOP(M 16.5 SD 4.02 SE 0.558), phakia, age (M 68.3, SD 15.15, SE 2.062), C:D ratio (M 0.48 V 0.58 H, SD 0.19 V 0.18 H, SE 0.035 V and 0.033 H), BP (M 136/79, SD 17.71 Sys 12.04 Dia, SE 2.410 Sys, 1.639 Dia) and weight (M 75.48, SD 15.92, SE 2.486). SVPs were detected in 32 of 54 patients using direct ophthalmoscopy, and in 33 of 54 patients using a 66D lens and slit lamp. The ophthalmologists using direct ophthalmoscope and the 66D lens agreed in 49 of 54 cases, giving an inter-rater reliability of 91%. All patients were found to have SVP on vOCT.
Conclusions
Ophthalmoscopically-assessed SVP has a high inter-observer agreement in normal subjects. However, 26% of patients with apparently normal ICP had no ophthalmoscopically detectable SVP. Conversely, SVP was detectable in all patients with apparently normal ICP by vOCT, suggesting it may be a more useful clinical assessment than ophthalmoscopically assessed SVP-detection.
