6 symptomatic patients – 5 pts abnormal mfERG (1 had Humph 10-2) – Early screening device? So SC et al 2003 11 patients (10 asymptomatic/1 symptomatic) – 7 pts abnormal mfERG (normal AVF) – Preclinical toxicity? Penrose PJ et al 2004 15 patients – 7 pts abnormal mfERG (3 normal HVF 30/24-2)) – mfERG useful in identifying retinal cause when VF abnormal – may detect abnormalities earlier than other tests Maturi RK et al 2004
mfERG early toxicity screening? Inclusion criteria: – >5 years on hydroxychloroquine – >18 years old – Normal ophthalmologic exam – Normal VF (Humphrey 10-2 Red) – No history of retinal disease
Complete ophthalmologic exam: – VA – Slit lamp – Tonometry – Color vision (Ishihara) – Fundus – Visual Field (Humphrey 10-2 Red) – Red Amsler mfERG
CONCLUSION mfERG may be useful as the first indicator of developing macular toxicity even when the “standard” tests are normal. mfERG possibly should be added as an investigation in patients at higher risk to develop toxicity.
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