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Electrophysiology in pseudohistoplasmosis and chronic idiopathic retinal vasculitis
L Pereira-Neves1, J Ribeiro-da-Silva
1Lisbon Institute of Ophthalmology, Lisbon Faculty of Medicine, Portugal.
Insights
Computerized electroretinography revealed distinct electrophysiological profiles in patients with pseudohistoplasmosis (P.S.H.) and chronic idiopathic retinal vasculitis (C.I.R.V.). P.S.H. showed high correlation across wavelengths, suggesting efficient phototransduction, while C.I.R.V. may involve rod-selective dysfunction.
Area of Science:
- Ophthalmology
- Neuroscience
- Medical Imaging
Background:
- Retinal diseases like pseudohistoplasmosis (P.S.H.) and chronic idiopathic retinal vasculitis (C.I.R.V.) can impact visual function.
- Electrophysiological testing, specifically electroretinography (E.R.G.), is crucial for assessing retinal function in various ocular conditions.
Purpose of the Study:
- To electrophysiologically differentiate between P.S.H. and C.I.R.V. using computerized electroretinography (E.R.G.).
- To compare E.R.G. findings in patients with P.S.H. and C.I.R.V. against healthy controls.
Main Methods:
- Computerized electroretinography (E.R.G.) flash was employed to assess 12 patients (5 P.S.H., 7 C.I.R.V.) and 12 healthy controls.
- Analysis focused on the correlation of b-wave amplitude across different light wavelengths (white, red, orange, blue) under scotopic and photopic conditions.
Main Results:
- Healthy controls showed moderate correlations between white light and other wavelengths.
- P.S.H. patients exhibited highly significant correlations across all tested wavelengths and conditions, indicating efficient phototransduction.
- C.I.R.V. patients showed no white-red correlation and lacked a scotopic white-blue correlation, suggesting potential rod-selective dysfunction.
Conclusions:
- Pseudohistoplasmosis (P.S.H.) and chronic idiopathic retinal vasculitis (C.I.R.V.) have distinct electrophysiological characteristics.
- The findings suggest that P.S.H. involves more efficient phototransduction, while C.I.R.V. may be associated with rod-specific retinal dysfunction.
Abstract:
We used computerized electroretinography (E.R.G.) flash to study 12 patients: five pseudohistoplasmosis (P.S.H.) and seven chronic idiopathic retinal vasculitis (C.I.R.V.), compared with 12 healthy controls. We found a moderate correlation in controls between white computer averaged b-wave amplitude and b-wave obtained with other wavelengths (over 600 nm red, over 550 nm orange, and under 500 nm blue), in scotopic (white/orange r = 0.41, P < 0.05; white/red r = 0.45, P < 0.05; white/blue r = 0.48, P < 0.02) and photopic conditions (white/orange r = 0.6, P < 0.01). For P.S.H. there was a highly significant correlation between white and all wavelengths in photopic (white/orange r = 1, white/red r = 0.96, P < 0.0001) and scotopic conditions (white/orange r = 0.97, P < 0.0001; white/red r = 0.96, P < 0.0001; white/blue r = 0.96). In vasculitis, as in controls, we found no white/red correlation and only in vasculitis we could not find a scotopic white/blue correlation. We conclude that these situations are electrophysiologically different. The closer correlation in P.S.H. suggests more efficient phototransduction and in C.I.R.V. there may also be a rod-selective dysfunction.