Top images demonstrate the actual mfERGs in one specific normal subject. The bottom images compare these results to the normative database. The central hill in the images left (top images) from a normal subject demonstrates increased sensitivity of the macula. According to the color code in the images below, the normal subject varies very
Introduction to mfERGs The typical stimulus for multifocal electroretinogram (mfERG) is shown in the left image above. Usually, 103 hexagons pattern reverse from white to black and black to white in a pseudo- random sequence. The resultant response from the retina is a topographically accurate ERG from 103 different locations. The total field size
Use of mfERGs for the Detection of Early Plaquenil Toxicity in a Different Case A 60 year old asymptomatic white female who has been on Plaquenil for over 10 years presented for a routine eye exam. Visual acuities were 20/20 OU. The ophthalmoscopic exam was normal as well as the fundus images as demonstrated.
Diagnosis: Plaquenil Retinal Toxicity Although this unfortunate, symptomatic patient has somewhat advanced retinal toxicity with abnormal visual acuity, visual fields and color vision, her fundus exam is still normal. It is likely that asymptomatic patients with normal VA but early Plaquenil toxicity (perhaps documented by ring scotomas or color vision loss) will also present
Zeiss Humphrey Visual fields 10-2 revealed an advanced Bull's Eye type defect OD and a large central scotoma OS. (It is probable that the field loss OS initially presented as a Bull's Eye defect such as in the OD)
Gray Scale vs. Color Scale The images above demonstrate inferior sections of the left eye in gray and color scale. As a general rule, gray scale images are somewhat more superior to color images in the analysis of the PIL.
The images above demonstrate superior and inferior Cirrus sections through the left eye in our 50 year old patient with deteriorating vision due to Plaquenil toxicity. Sections superior (above) and inferior (below) to the fovea in the left eye reveal the presence, absence and disorganization of the PIL/junction as shown. In both scans, the PIL
The images above demonstrate superior and inferior Cirrus sections through the right eye in our 50 year old patient with deteriorating vision due to Planquenil toxicity. The macula appears elevated OD (less so OS) perhaps because of increased choroidal thickening.
Right and Left Eye Cirrus Scans Through the Fovea The images above demonstrate Cirrus scans through the fovea In our 50 year old patient with deteriorating vision due to Plaquenil toxicity. Under the foveal pit, the PIL was relatively Intact OD but absent OS, which correlates with the asymmetric visual acuities. The PIL was
Although the photoreceptor integrity line, or the PIL (defined as the junction between the inner and outer segments) is barely visible in most histological sections, it is highly prominent in SD OCTs. PIL, as shown to the left, should be continuous throughout the entire scan in normal eyes. The PIL/junction can be considered a