Isolated mesopic rod and cone electroretinograms realized with a four-primary method

Cao, Dingcai; Pokorny, Joel; Grassi, Michael A.

doi:10.1007/s10633-011-9279-9

Cited by 20 publications

(33 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Most electroretinographic studies in the literature focus on specific luminance ranges, in which the results agree well with our findings [3,6,[11][12][13][14]. However, these studies in general do not include or do not specifically investigate the luminance range where the transition from rod-to cone-driven responses can be found.…”

Section: Discussionsupporting

confidence: 89%

“…Early works to analyze luminance tracking in the ERG response [7,8] have applied flash stimuli that clearly elicit different ERG responses when compared to flicker type stimulation [6,9]. While also standard ISCEV protocols are based on flashed stimuli [2], several research groups [3,6,[9][10][11][12][13][14] used different temporal flicker modulations to stimulate the retina and the visual system.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Human flicker electroretinography using different temporal modulations at mesopic and photopic luminance levels

et al. 2014

View full text Add to dashboard Cite

show abstract

Section: Discussionsupporting

confidence: 89%

Section: Introductionmentioning

confidence: 99%

Human flicker electroretinography using different temporal modulations at mesopic and photopic luminance levels

et al. 2014

View full text Add to dashboard Cite

show abstract

“…However, amplitudes decrease frequency-dependent from around 300 lV at 1 Hz to less than 5 lV at 15 Hz under dark adapted conditions. This decrease in rod amplitudes with raising frequencies has recently been shown for a silent substitution technique [39].The slow pathway involving the rod bipolar cells is able to follow flicker stimulation only up to 15 Hz [38]. As described previously, averaging a high number of recordings (N) is needed to enhance the SNR [21,26].…”

Section: The 9 Hz Flicker Protocolmentioning

confidence: 76%

“…For technical assistance with measurements of Doc Ophthalmol (2012) 124: [27][28][29][30][31][32][33][34][35][36][37][38][39] …”

mentioning

confidence: 99%

Assessment of “non-recordable” electroretinograms by 9 Hz flicker stimulation under scotopic conditions

et al. 2011

View full text Add to dashboard Cite

To refine methods of electroretinographical (ERG) recording for the analysis of low retinal potentials under scotopic conditions in advanced retinal degenerative diseases. Standard Ganzfeld ERG equipment (Diagnosys LLC, Cambridge, UK) was used in 27 healthy volunteers (mean age 28 ± SD 8.5 years) to define the stimulation protocol. The protocol was then applied in clinical routine and 992 recordings were obtained from patients (mean age 40.6 ± 18.3 years) over a period of 5 years. A blue stimulus with a flicker frequency of 9 Hz was specified under scotopic conditions to preferentially record rod-driven responses. A range of stimulus strengths (0.0000012-6.32 scot. cd s/m² and 6-14 ms flash duration) was tested for maximal amplitudes and interference between rods and cones. Analysis of results was done by standard Fourier Transformation and assessment of signal-to-noise ratio. Optimized stimulus parameters were found to be a time-integrated luminance of 0.012 scot. cd s/m² using a blue (470 nm) flash of 10 ms duration at a repetition frequency of 9 Hz. Characteristic stimulus strength versus amplitude curves and tests with stimuli of red or green wavelength suggest a predominant rod-system response. The 9 Hz response was found statistically distinguishable from noise in 38% of patients with otherwise non-recordable rod responses according to International Society for Clinical Electrophysiology of Vision standards. Thus, we believe this protocol can be used to record ERG potentials in patients with advanced retinal diseases and in the evaluation of potential treatments for these patients. The ease of implementation in clinical routine and of statistical evaluation providing an observer-independent evaluation may further facilitate its employment.

show abstract

“…As mentioned above, this study teased out rod-and medium-to long-wavelength cone subtypespecific contributions to the mouse flicker ERG under identical adaptation conditions. Compared with mice, spectral isolation of individual photoreceptor types in the human retina has received more attention (Bessler et al 2010;Brainard et al 2000;Cao et al 2011;Challa et al 2010;Kremers et al 2000Kremers et al , 2009Kremers and Link 2008;Kremers and Scholl 2001), which has allowed more detailed investigations. Even so, few have examined rod-only contributions to the flicker ERG (Cao et al 2011;Kremers and Pangeni 2012), because its isolation from S-cones with reasonable strength is difficult [i.e., max of S-cone ϳ 435 nm vs. rod ϳ 495 nm (Kraft et al 1993;Stockman and Sharpe 2000)].…”

Section: Discussionmentioning

confidence: 99%

Rod- and cone-driven responses in mice expressing human L-cone pigment

Tsai

Atorf

Neitz

et al. 2015

Journal of Neurophysiology

View full text Add to dashboard Cite

Tsai TI, Atorf J, Neitz M, Neitz J, Kremers J. Rod-and cone-driven responses in mice expressing human L-cone pigment. J Neurophysiol 114: 2230 -2241, 2015. First published August 5, 2015 doi:10.1152/jn.00188.2015.-The mouse is commonly used for studying retinal processing, primarily because it is amenable to genetic manipulation. To accurately study photoreceptor driven signals in the healthy and diseased retina, it is of great importance to isolate the responses of single photoreceptor types. This is not easily achieved in mice because of the strong overlap of rod and M-cone absorption spectra (i.e., maxima at 498 and 508 nm, respectively). With a newly developed mouse model (Opn1lw LIAIS ) expressing a variant of the human L-cone pigment (561 nm) instead of the mouse M-opsin, the absorption spectra are substantially separated, allowing retinal physiology to be studied using silent substitution stimuli. Unlike conventional chromatic isolation methods, this spectral compensation approach can isolate single photoreceptor subtypes without changing the retinal adaptation. We measured flicker electroretinograms in these mutants under ketamine-xylazine sedation with double silent substitution (silent S-cone and either rod or M/L-cones) and obtained robust responses for both rods and (L-)cones. Small signals were yielded in wild-type mice, whereas heterozygotes exhibited responses that were generally intermediate to both. Fundamental response amplitudes and phase behaviors (as a function of temporal frequency) in all genotypes were largely similar. Surprisingly, isolated (L-)cone and rod response properties in the mutant strain were alike. Thus the LIAIS mouse warrants a more comprehensive in vivo assessment of photoreceptor subtype-specific physiology, because it overcomes the hindrance of overlapping spectral sensitivities present in the normal mouse. keywords electrophysiology; mouse; photoreceptors; silent substitution IN RECENT YEARS, THE MOUSE has been the mainstay model for studying the physiology of the retina and retinal diseases. In vivo studies of retinal electrophysiology can be achieved by electroretinography (ERG). This method is noninvasive and enables repeated measurements from the same animal. Recent developments in ERG recordings in humans have shown that ERGs not have only a clinical value but also may give information on information processing in major retinogeniculate pathways with relevance for basic visual neuroscience (Kremers and Link 2008;Kremers et al. 2010;Parry et al. 2012). This relevance was recently confirmed for the mouse (Allen et al. 2014). To be able to study retinal signal processing and its disease-related changes, it is of great importance to isolate the responses of single photoreceptor types and record the signals that each elicits downstream. Also, in other studies of the retinal physiology, isolation of photoreceptor responses may lead to a better understanding of the information processing in the retina and for associated visual functions (Brown et al. 2010(Brown et al. , 2...

show abstract

Isolated mesopic rod and cone electroretinograms realized with a four-primary method

Cited by 20 publications

References 40 publications

Human flicker electroretinography using different temporal modulations at mesopic and photopic luminance levels

Human flicker electroretinography using different temporal modulations at mesopic and photopic luminance levels

Assessment of “non-recordable” electroretinograms by 9 Hz flicker stimulation under scotopic conditions

Rod- and cone-driven responses in mice expressing human L-cone pigment

Contact Info

Product

Resources

About