Focal macular ERGs elicited by different stimulus intensities from a normal subject.

<p>A: A 10° spot of was projected onto the macula. B: A 5° stimulus spot was projected onto the macula. C: The round stimulus was projected onto the optic disc. The spot size was controlled to correspond to the optic disc. The stimulus duration is 100 ms and the luminance of the constant background illumination is 3.0 cd/m². An increase in the amplitudes of each component is observed with increasing luminance but the implicit times appear to be constant. The iFMERGs recorded by the stimulus projected on the optic nerve head were non-recordable when the intensity was ≤270 cd/m² indicating that this stimulus intensity could elicit a focal response only from the macula with negligible stray light effect.</p

iFMERGs recorded from a normal eye.

<p>Upper: Waveform of iFMERG elicited by a long duration stimulus. Bottom: Oscillatory potentials of focal macular ERGs elicited by a 10° diameter stimulus.</p

Effect of stimulus duration on intraoperative focal macular electroretinograms from a normal eye.

<p>With shorter stimulus durations, the total light energy was relative low therefore the amplitude of b-wave was relative small. But with shorter duration the b- and d-waves (on and off responses) became closer and merged with stimuli intervals less than 17 ms.</p

Stimulus intensity vs b-wave amplitude for stimulus spot projected onto the macula and onto the optic nerve head.

<p>The size of the stimulus was 5°. A stimulus spot that was approximately 1.75 log unit brighter than the background light was able to elicit a focal macular response.</p

Intraoperative focal macular electroretinograms recorded from different retinal sites.

<p>iFMERGs were elicited by circular stimuli placed at 9 sites on the retina. The a-, b-, and d-waves in the central area are larger than those in the peripheral area. The implicit time of each component was shorter in the central area and longer at the more peripheral areas.</p

Schematic diagrams of the two stimulus conditions.

<p>The stimuli used for conventional focal macular electroretinograms (FMERGs; left) and the intraoperative iFMERG (right) are shown. Because the focal stimuli using an endolaser probe was directly delivered to the macula without passing through the ocular media, the stray light effect is minimized.</p

Photograph showing operating condition during the recording of the iFMERGs.

<p>A gold-foil monopolar contact lens electrode (Mayo Corporation, Nagoya, Japan) was sterilized and placed on the cornea (arrowhead) of the examined eye to pick up the iFMERGs. A dual port 29G Oshima chandelier light probe (Synergetics, O’Fallon, MO, USA) was used for background light (arrow). A 25G flexible directional fiber probe (Synergetics, O’Fallon, MO, USA) was used to deliver the stimuli to the retina (dotted line arrow).</p

Appearance of an eye during intraoperative electroretinographic recordings.

<p>A contact lens with a built-in light-emitting diode (LS-100, Mayo Co, Inazawa, Japan) was sterilized and used as both the stimulus source and recording electrode for photopic ERGs.</p

Measurements of the amplitude and the latency of the oscillatory potentials (OPs).

<p>The amplitude (upper) and latency (lower) of each OP are shown. bar represents the beginning and duration of the stimulus flash.</p

The amplitude of each component and the intravitreal temperature before and after core vitrectomy.

<p>The amplitude of the on-PhNR, OP2, OP3, OP4, and OP5 decreases significantly after core vitrectomy. PhNR: photopic negative response, OP: oscillatory potential, bar indicates standard error. *<i>P</i> <0.05, **<i>P</i> <0.01, ***<i>P</i> <0.001.</p