Electrophysiological findings in patients with dengue-related maculopathy.
OBJECTIVE
To assess visual function in patients with dengue maculopathy using electrophysiological tests.


METHODS
Fifteen consecutive patients with dengue fever who experienced vision loss between July 2004 and July 2005 were included in this review. Full-field electroretinograms (ERG), pattern ERGs, and multifocal ERGs were performed.


RESULTS
The most common electrophysiological finding (60%, 9/15) was a normal or mildly abnormal full-field ERG with reduced pattern ERG P50 amplitude and abnormal mfERG. Typically, multifocal ERG demonstrated a focal area of decreased macular response (especially between the fovea and optic nerve). Pattern ERG suggested normal optic nerve function in all but 1 case. Four patients had more severely reduced full-field ERG responses with reduced a-wave amplitude (suggestive of photoreceptor dysfunction), 3 of whom had an electronegative maximal response (suggestive of additional postreceptor dysfunction). Repeat multifocal ERG showed little change in 7 patients and incomplete resolution in 2 patients over 3 to 10 months.


CONCLUSIONS
Retinal dysfunction associated with dengue maculopathy was localized mainly around the foveal region. It appeared to affect the outer and middle retina more severely with relative sparing of the inner retina. Retinal dysfunction may persist for several months. Longer follow-up is required to determine whether these changes are permanent.
Chia
Audrey
A
Singapore National Eye Centre, Singapore. wla_chia@yahoo.com
Luu
Chi D
CD
Mathur
Ranjana
R
Cheng
Bobby
B
Chee
Soon Phaik
SP
D000293:Adolescent; D000328:Adult; D002648:Child; D003715:Dengue / Q000503:physiopathology* / Q000821:virology; D004594:Electrophysiology; D004596:Electroretinography; D015828:Eye Infections, Viral / Q000503:physiopathology* / Q000821:virology; D005260:Female; D006801:Humans; D008297:Male; D012160:Retina / Q000503:physiopathology*; D012164:Retinal Diseases / Q000503:physiopathology* / Q000821:virology; D014786:Vision Disorders / Q000503:physiopathology / Q000821:virology; D014794:Visual Fields