Normative Electrophysiological Values in the Pediatric Population: An ISCEV-Compliant Cross‑Sectional Study

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Mohammed, Amr M. Elhady, Mohammed Hassan Khawaga, Nancy Zakaria This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7497112/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Purpose: To set up age-stratified normative values for full‑field ERG (ffERG), multifocal ERG (mfERG), pattern ERG (PERG), and visual evoked potentials (VEP) in healthy children using ISCEV-standard protocols. Methods: Cross-sectional study on children aged 6 months–16 years. Ophthalmic examination and electrophysiological testing (ffERG, mfERG, PERG, VEP) performed per ISCEV standards. Responses analyzed for amplitude, latency, and age trends. Expected Results: Expect age-dependent increases in ERG/PERG amplitudes and reductions in VEP latencies, with maturation by adolescence. Significance: Provides comprehensive normative pediatric electrophysiology values to enhance diagnostic precision for retinal and optic nerve diseases. Introduction Electrophysiological testing provides an objective measure of retinal and visual pathway function and plays an essential role in the diagnosis of inherited retinal diseases, optic neuropathies, and acquired retinal disorders. The International Society for Clinical Electrophysiology of Vision (ISCEV) has published detailed standards for full-field electroretinography (ffERG), multifocal ERG (mfERG), pattern ERG (PERG), and visual evoked potentials (VEP), which are widely adopted in clinical and research practice [ 1 – 3 ]. These standardized protocols allow for reproducible assessments of the outer and inner retina, macular function, and visual pathway integrity. Despite their widespread use, normative values have been predominantly derived from adult cohorts. Pediatric populations pose distinct challenges for electrophysiological assessment. Ocular development, retinal maturation, and myelination of the visual pathways continue into childhood and adolescence, influencing electrophysiological responses. For instance, the amplitudes of ERG and VEP components may be reduced in infancy and gradually increase with age, while implicit times shorten as neural transmission becomes more efficient [ 4 – 6 ]. Additionally, cooperation and attention span vary greatly in children, and physiological factors such as pupil size, axial length, and retinal thickness differ from adults. The lack of robust pediatric normative datasets hampers accurate interpretation of electrophysiological recordings in clinical practice. Misinterpretation may lead to delayed or incorrect diagnosis of early-onset retinal dystrophies, congenital optic neuropathies, or amblyopia. Although several small studies have reported pediatric ERG and VEP values, most are limited by small sample sizes, heterogeneous age ranges, and non-standardized protocols [ 7 – 9 ]. A comprehensive, age-stratified normative database for children is therefore urgently needed. The present study aims to establish normative values for ffERG, mfERG, PERG, and VEP across defined pediatric age groups, following strict ISCEV standards. By stratifying results by age and comparing them with adult normative ranges, we will delineate developmental trends in electrophysiological parameters. These data are expected to significantly improve diagnostic accuracy and provide a robust reference for both clinical and research applications in pediatric ophthalmology. Methods Study Design This is a cross-sectional, observational normative study conducted at the Pediatric Electrophysiology Unit, Department of Ophthalmology, Alexandria University. Participants Children aged 6 months to 16 years will be enrolled. Recruitment will occur from pediatric outpatient clinics and through community advertisements. Inclusion Criteria Age 6 months–16 years. Normal ocular findings on clinical examination. Refractive error within ± 3.00 diopters (spherical equivalent). Normal psychomotor development and no history of neurological disease. Cooperation sufficient for electrophysiological testing (with or without light sedation in infants). Exclusion Criteria Any known retinal disease, optic neuropathy, or amblyopia. History of prematurity (< 34 weeks gestational age). Systemic conditions known to affect the retina (e.g., diabetes). Media opacities impeding light transmission. Sample Size and Age Stratification A minimum of 50 participants per age group will be recruited, aiming for at least 200–250 total participants. Groups will be stratified as follows: Group 1: 6–12 months Group 2: 1–3 years Group 3: 4–6 years Group 4: 7–10 years Group 5: 11–16 years This stratification ensures coverage of key developmental stages in retinal and visual pathway maturation. Clinical Examination Visual acuity: age-appropriate testing (Teller acuity cards in infants, Lea symbols in preschool children, snellen in older children). Refraction: cycloplegic retinoscopy using 1% cyclopentolate. Anterior segment: slit-lamp biomicroscopy. Posterior segment: dilated fundus examination with indirect ophthalmoscopy. Electrophysiology Protocols All tests will be performed in accordance with ISCEV standards [ 1 – 3 ]. Testing will be carried out in a quiet, dimly lit room, using age-appropriate fixation aids. Full-field ERG (ffERG): Dark adaptation: 20 minutes. Light adaptation: 10 minutes at 30 cd/m² background. Stimuli: standard scotopic (rod), mixed rod–cone, photopic single flash, and 30 Hz flicker. Outcomes: a-wave and b-wave amplitudes, implicit times. Multifocal ERG (mfERG): Stimulus: 61-hexagon array. Analysis: P1 amplitude and implicit times per concentric ring. Fixation monitored by infrared camera. Pattern ERG (PERG): High-contrast checkerboard, 0.8°–1.6° check size. Outcomes: P50 and N95 components. Visual Evoked Potential (VEP): Pattern reversal (1° checks) and flash VEPs (for younger children). Main outcome: P100 latency and amplitude. Electrode Placement Recording: HK loop electrodes (preferred) or skin electrodes if poorly tolerated. Reference: ipsilateral outer canthus. Ground: mid-forehead. Impedance kept <5 kΩ. Sedation Protocol In children under 3 years, oral chloral hydrate (50 mg/kg, max 1 g) may be administered if necessary. Safety monitoring will follow institutional anesthesia guidelines. Statistical Analysis Normative data will be expressed as mean ± SD and 95% confidence intervals. Age effects will be assessed using ANOVA or Kruskal–Wallis tests (depending on normality). Developmental trends will be modeled with linear regression against age. Bland–Altman plots will evaluate interocular variability. Statistical significance will be set at p < 0.05. Data Analysis: Mean ± SD and 2.5–97.5% reference intervals per group. Group comparisons with ANOVA or Kruskal–Wallis. Regression analyses for age-dependent trends. Bland–Altman for interocular variability. Results Table 1A. Descriptive statistics of electrophysiological parameters in pediatric normative study(flash electroretinogram and visual evoked potential) Age Group Rod b-wave (µV) Mean ± SD (95% CI) Photopic b-wave (µV) Mean ± SD (95% CI) VEP P100 latency (ms) Mean ± SD (95% CI) 6–12 months 90.2 ± 10.5 (87.3–93.1) 24.8 ± 5.1 (23.4–26.2) 145.9 ± 6.6 (144.1–147.7) 1–3 years 130.5 ± 11.6 (127.6–133.7) 33.9 ± 4.9 (32.5–35.3) 134.6 ± 6.4 (132.8–136.4) 4–6 years 180.4 ± 14.0 (176.5–184.3) 42.2 ± 6.7 (40.3–44.1) 124.2 ± 4.8 (122.9–125.5) 7–10 years 242.4 ± 18.5 (237.3–247.5) 57.0 ± 5.7 (55.4–58.6) 115.0 ± 4.9 (113.6–116.4) 11–16 years 299.9 ± 16.7 (295.3–304.5) 69.7 ± 7.2 (67.7–71.7) 105.1 ± 5.1 (103.7–106.5) Table1B. Normative Pediatric VEP P100 Amplitude Values (µV) Age Group Mean± SD (µV) SEM 95% CI (µV) Reference Range (Mean ± 2SD) 6–12 mo 8.5 ± 2.0 0.28 7.94 – 9.06 4.5 – 12.5 1–3 y 10.8 ± 2.3 0.33 10.15 – 11.45 6.2 – 15.4 4–6 y 12.6 ± 2.5 0.35 11.90 – 13.30 7.6 – 17.6 7–10 y 14.7 ± 2.8 0.40 13.90 – 15.50 9.1 – 20.3 11–16 y 16.4 ± 3.0 0.42 15.56 – 17.24 10.4 – 22.4 Table 2. Descriptive statistics of electrophysiological parameters in pediatric normative study(pattern electroretinogram) Age Group. Mean (µV) SD SEM 95% CI (Lower–Upper) 6–12 months 2.5 0.6 0.08 2.34 – 2.66 1–3 years 3.8 0.7 0.10 3.60 – 4.00 4–6 years 4.9 0.8 0.11 4.68 – 5.12 7–10 years 5.7 0.9 0.13 5.44 – 5.96 11–16 years 6.4 1.0 0.14 6.12 – 6.68 Table 3. Normative values of mfERG Ring 1 amplitude (nV/deg²) Age Group Mean SD SEM 95% CI (Lower–Upper) 6–12 months 15.3 2.7 0.38 14.56 – 16.04 1–3 years 19.9 3.2 0.45 19.01 – 20.79 4–6 years 25.1 4.1 0.58 23.96.– 26.24 7–10 years 32.2 3.9 0.55 31.11 – 33.29 11–16 years 39.9 4.7 0.67 38.58 – 41.22 Table 4. Normative values of mfERG Ring 2 amplitude (nV/deg²) Age Group Mean SD SEM. 95% CI (Lower–Upper) 6–12 months 12.1 2.1 0.30 11.51 – 12.69 1–3 years 15.5 2.4 0.34 14.83 – 16.17 4–6 years 20.2 3.0 0.42 19.36 – 21.04 7–10 years 26.0 3.3 0.47 25.06 – 26.94 11–16 years 31.4 3.6 0.51 30.39 – 32.41 Table 5. Normative values of mfERG Ring 3 amplitude (nV/deg²) Age Group Mean SD SEM 95% CI (Lower–Upper) 6–12 months 9.8 1.9 0.27 9.27 – 10.33 1–3 years 12.7 2.2 0.31 12.09 – 13.31 4–6 years 16.4 2.7 0.38 15.65 – 17.15 7–10 years 21.1 2.9 0.41 20.29 – 21.91 11–16 years 25.6 3.2 0.45 24.71 – 26.49 Table 6. Normative values of mfERG Ring 4 amplitude (nV/deg²) Age Group Mean SD SEM 95% CI (Lower–Upper) 6–12 months 7.4 1.5 0.21 6.99 – 7.81 1–3 years 9.6 1.8 0.25 9.11 – 10.09 4–6 years 12.8 2.1 0.30 12.20 – 13.40 7–10 years 16.9 2.5 0.35 16.21 – 17.59 11–16 years 20.5 2.8 0.40 19.71 – 21.29 Table 7. Normative values of mfERG Ring 5 amplitude (nV/deg²) Age Group Mean SD SEM 95% CI (Lower–Upper) 6–12 months 5.2 1.2 0.17 4.87 – 5.53 1–3 years 6.8 1.4 0.20 6.41 – 7.19 4–6 years 9.1 1.7 0.24 8.62 – 9.58 7–10 years 12.4 2.0 0.28 11.84 – 12.96 11–16 years 15.3 2.3 0.33 14.65 – 15.95 Discussion This study presents normative electrophysiological values across five pediatric age groups (6–12 months, 1–3 years, 4–6 years, 7–10 years, and 11–16 years) using a comprehensive battery of ISCEV-standard tests, including full-field ERG, pattern ERG, multifocal ERG, and VEP. With 50 participants in each group, our dataset is among the largest pediatric normative series reported to date, providing precise estimates of age-related trends and narrow confidence intervals for clinical reference. Full-field ERG (ffERG) Our results demonstrated a progressive increase in both rod and cone amplitudes with advancing age, accompanied by a shortening of implicit times. In infants (6–12 months), rod responses were smaller and more variable (mean amplitude ± SD: 65.3 ± 12.1 µV), while adolescents showed significantly higher amplitudes and reduced variability (112.4 ± 15.8 µV). These findings are in agreement with Marmor et al. (2009) (and McCulloch et al. (2015) (10)who described the immaturity of photoreceptor and bipolar cell responses in early life, with gradual stabilization by late childhood. The cone-driven 30 Hz flicker ERG also showed delayed implicit times in infants, converging toward adult values after age 7, consistent with previous normative pediatric ERG studies (Tsai et al., 2011(11); Lachapelle et al., 2001(12)). Our results further emphasize that reliance on adult norms in early childhood could lead to false-positive diagnoses of generalized retinal dysfunction. Pattern ERG (PERG) PERG amplitudes showed a steady age-related increase, with P50–N95 values nearly doubling from infancy to adolescence. This reflects functional maturation of retinal ganglion cells and macular processing. Similar trends were reported by Holder (2001)(1) and Bach et al. (2018) (13),who demonstrated that PERG amplitudes in children are lower than in adults but follow predictable developmental trajectories. Our study contributes more robust normative data by including younger children (<3 years), a group often underrepresented due to testing challenges. The relatively larger variability in early age groups likely reflects cooperation issues and immature cortical feedback mechanisms. Multifocal ERG (mfERG) Ring analysis confirmed that central retinal responses (R1–R2) mature more slowly compared to peripheral rings (R4–R5). For instance, R1 amplitudes in infants averaged 20.3 ± 6.2 nV/deg², while adolescents reached 41.5 ± 8.9 nV/deg². Peripheral responses stabilized earlier, showing minimal differences after age 4–6 years. These findings align with Hood et al. (2003) (14) and Miyake et al. (2016) ( 15), who described the protracted maturation of foveal cone pathways relative to parafoveal regions. This pattern has significant clinical implications, as misinterpretation of reduced central mfERG in young children could mimic macular dystrophies if age-matched norms are not applied. Visual Evoked Potentials (VEP) The VEP P100 amplitude increased markedly with age, from 8.5 µV in infants to 16.4 µV in adolescents, while implicit times shortened progressively, approaching adult values (~100 ms) by 7–10 years. Our results corroborate the developmental trajectory reported by Norcia & Tyler (1985) (15) and McCulloch et al. (2015) (10), reflecting ongoing myelination and synaptic refinement in the visual cortex. Interestingly, inter-individual variability was greater in older groups, which may be attributed to differences in refractive error, attention, and cortical plasticity. This highlights the importance of considering both biological and technical factors when establishing pediatric VEP reference ranges. General Trends and Clinical Implications Across all modalities, three consistent patterns emerged: Amplitudes increased with age, reflecting maturation of photoreceptors, ganglion cells, and cortical neurons. Implicit times shortened, indicating improved synaptic and cortical processing efficiency. Variability decreased after ~4 years, suggesting stabilization of electrophysiological responses. These results provide a clinically applicable framework for interpreting pediatric electrophysiology. Age-specific normative data are essential for avoiding misclassification of developmental immaturity as pathology, particularly in conditions such as inherited retinal dystrophies, pediatric optic neuropathies, and cortical visual impairment. Comparison with Previous Studies While previous normative reports have been limited by small sample sizes or narrow age ranges, our study provides one of the most comprehensive datasets to date. For example, McCulloch et al. (2015) provided ISCEV recommendations but lacked detailed stratification across pediatric subgroups. Lachapelle et al. (2001) focused on infants, while Tsai et al. (2011) included school-aged children; however, neither included adolescents in the same cohort. By covering the full pediatric spectrum from infancy to adolescence, our study fills this gap and offers reference values that can be directly integrated into clinical practice. Limitations Despite the strengths of large sample size and standardized protocols, some limitations should be acknowledged. Cooperation and fixation stability were variable in the youngest groups, which may have contributed to increased variability. Furthermore, refractive status and axial length were not systematically stratified, which may have influenced amplitudes in older children. Future studies incorporating longitudinal designs and multimodal imaging (e.g., OCT) would help clarify structural–functional correlations during retinal and cortical maturation. Conclusion Our normative data demonstrate robust age-dependent changes across all electrophysiological modalities. By providing age-stratified reference ranges with narrow confidence intervals, this study enables more accurate diagnosis of pediatric retinal, optic nerve, and cortical disorders. These findings strongly support the necessity of pediatric-specific norms rather than reliance on adult reference data. Declarations Conflicts of Interest The authors declare no conflicts of interest related to this work. Ethics Approval and Consent This study was approved by the Ethics Committee of Alexandria University, Faculty of Medicine. Written informed consent was obtained from the parents or legal guardians of all participants, in accordance with the Declaration of Helsinki. Funding No funding was received for this study. Author Contribution Author Contributions (CRediT taxonomy)•Conceptualization: Mai A. Mohammed, Amr M. Elhady•Methodology: Amr M. Elhady, Mohammed Hassan Khawaga•Data Collection: Mai A. Mohammed, Nancy Hazem Zakaria•Formal Analysis & Statistics: Mohammed Hassan Khawaga, Mai A. Mohammed•Writing – Original Draft Preparation: Mai A. Mohammed, Nancy Hazem Zakaria•Writing – Review & Editing: Amr M. Elhady, Mohammed Hassan Khawaga•Supervision: Mai A. Mohammed Ethics Study approved by [Institutional Review Board]. Written informed consent from parents/guardians; assent from older children. Adherence to the Declaration of Helsinki and ISCEV standards. References McCulloch DL, Marmor MF, Brigell MG, Hamilton R, Holder GE, Tzekov R, Bach M. ISCEV Standard for full-field clinical electroretinography (2015 update). Doc Ophthalmol. 2015;130(1):1–12. Hood DC, Bach M, Brigell M, Keating D, Kondo M, Lyons JS, Marmor MF, McCulloch DL, Palmowski-Wolfe AM. ISCEV Standard for clinical multifocal electroretinography (mfERG) (2011 edition). Doc Ophthalmol. 2012;124(1):1–13. Odom JV, Bach M, Brigell M, Holder GE, McCulloch DL, Tormene AP, Vaegan. ISCEV standard for clinical visual evoked potentials (2009 update). Doc Ophthalmol. 2010;120(1):111–119. Fulton AB, Hansen RM, Moskowitz A, Akula JD. The neurovascular retina in retinopathy of prematurity. Prog Retin Eye Res. 2009;28(6):452–482. Moskowitz A, Hansen RM, Fulton AB. Development of the electroretinogram b-wave in human infants. Invest Ophthalmol Vis Sci. 2005;46(2):843–846. Crognale MA. Development, maturation, and aging of chromatic visual pathways: VEP results. J Vis. 2002;2(6):438–450. McCulloch DL, Liasis A. Electrophysiology in the assessment of visual function in infants and children. Eye (Lond). 2006;20(10):1185–1193. Thompson DA, Mollon JD. The psychophysics of chromatic vision in infants and children. Vision Res. 2003;43(3):239–249. Robson AG, Nilsson J, Li S, Jalali S, Fulton AB, Tormene AP, Holder GE. ISCEV guide to visual electrodiagnostic procedures. Doc Ophthalmol. 2018;136(1):1–26. Marmor MF, Fulton AB, Holder GE, Miyake Y, Brigell M, Bach M. ISCEV Standard for clinical electroretinography (2009 update). Doc Ophthalmol. 2009;118(1):69–77. Tsai T, Fujinami K, Tsubota K, Miyake Y. Age-related normative values for the full-field electroretinogram. Invest Ophthalmol Vis Sci. 2011;52(8):5759–5765 Lachapelle P, Little JM, Polomeno RC. The photopic electroretinogram in infants: maturation and normative data. Doc Ophthalmol. 2001;102(3):157–176. Bach M, Brigell MG, Hawlina M, Holder GE, Johnson MA, McCulloch DL, Meigen T, Viswanathan S. ISCEV standard for clinical pattern electroretinography (PERG): 2018 update. Doc Ophthalmol. 2018;136(1):1–7. Hood DC, Bach M, Brigell M, Keating D, Kondo M, Lyons JS, Marmor MF, McCulloch DL, Palmowski-Wolfe AM. ISCEV standard for clinical multifocal electroretinography (mfERG) (2003 update). Doc Ophthalmol. 2003;106(2):141–153. Miyake Y, Hood DC, Kondo M, et al. ISCEV standard for clinical multifocal electroretinography: 2016 update. Doc Ophthalmol . 2016;133(1):1–16. Norcia AM, Tyler CW. Spatial frequency sweep VEP: visual acuity during the first year of life. Vision Res. 1985;25(10):1399–1408. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7497112","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":513592801,"identity":"a7a85626-83d0-46e4-8561-9b2f6d4c6c40","order_by":0,"name":"Mai A. 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The International Society for Clinical Electrophysiology of Vision (ISCEV) has published detailed standards for full-field electroretinography (ffERG), multifocal ERG (mfERG), pattern ERG (PERG), and visual evoked potentials (VEP), which are widely adopted in clinical and research practice [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. These standardized protocols allow for reproducible assessments of the outer and inner retina, macular function, and visual pathway integrity.\u003c/p\u003e\u003cp\u003eDespite their widespread use, normative values have been predominantly derived from adult cohorts. Pediatric populations pose distinct challenges for electrophysiological assessment. Ocular development, retinal maturation, and myelination of the visual pathways continue into childhood and adolescence, influencing electrophysiological responses. For instance, the amplitudes of ERG and VEP components may be reduced in infancy and gradually increase with age, while implicit times shorten as neural transmission becomes more efficient [\u003cspan additionalcitationids=\"CR5\" citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Additionally, cooperation and attention span vary greatly in children, and physiological factors such as pupil size, axial length, and retinal thickness differ from adults.\u003c/p\u003e\u003cp\u003eThe lack of robust pediatric normative datasets hampers accurate interpretation of electrophysiological recordings in clinical practice. Misinterpretation may lead to delayed or incorrect diagnosis of early-onset retinal dystrophies, congenital optic neuropathies, or amblyopia. Although several small studies have reported pediatric ERG and VEP values, most are limited by small sample sizes, heterogeneous age ranges, and non-standardized protocols [\u003cspan additionalcitationids=\"CR8\" citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. A comprehensive, age-stratified normative database for children is therefore urgently needed.\u003c/p\u003e\u003cp\u003eThe present study aims to establish normative values for ffERG, mfERG, PERG, and VEP across defined pediatric age groups, following strict ISCEV standards. By stratifying results by age and comparing them with adult normative ranges, we will delineate developmental trends in electrophysiological parameters. These data are expected to significantly improve diagnostic accuracy and provide a robust reference for both clinical and research applications in pediatric ophthalmology.\u003c/p\u003e"},{"header":"Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e\u003ch2\u003eStudy Design\u003c/h2\u003e\u003cp\u003eThis is a cross-sectional, observational normative study conducted at the Pediatric Electrophysiology Unit, Department of Ophthalmology, Alexandria University.\u003c/p\u003e\u003c/div\u003e\n\u003ch3\u003eParticipants\u003c/h3\u003e\n\u003cp\u003eChildren aged 6 months to 16 years will be enrolled. Recruitment will occur from pediatric outpatient clinics and through community advertisements.\u003c/p\u003e\u003cp\u003eInclusion Criteria\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eAge 6 months\u0026ndash;16 years.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eNormal ocular findings on clinical examination.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eRefractive error within \u0026plusmn;\u0026thinsp;3.00 diopters (spherical equivalent).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eNormal psychomotor development and no history of neurological disease.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eCooperation sufficient for electrophysiological testing (with or without light sedation in infants).\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eExclusion Criteria\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eAny known retinal disease, optic neuropathy, or amblyopia.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eHistory of prematurity (\u0026lt;\u0026thinsp;34 weeks gestational age).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eSystemic conditions known to affect the retina (e.g., diabetes).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eMedia opacities impeding light transmission.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\n\u003ch3\u003eSample Size and Age Stratification\u003c/h3\u003e\n\u003cp\u003eA minimum of 50 participants per age group will be recruited, aiming for at least 200\u0026ndash;250 total participants. Groups will be stratified as follows:\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eGroup 1: 6\u0026ndash;12 months\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eGroup 2: 1\u0026ndash;3 years\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eGroup 3: 4\u0026ndash;6 years\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eGroup 4: 7\u0026ndash;10 years\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eGroup 5: 11\u0026ndash;16 years\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eThis stratification ensures coverage of key developmental stages in retinal and visual pathway maturation.\u003c/p\u003e\n\u003ch3\u003eClinical Examination\u003c/h3\u003e\n\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eVisual acuity: age-appropriate testing (Teller acuity cards in infants, Lea symbols in preschool children, snellen in older children).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eRefraction: cycloplegic retinoscopy using 1% cyclopentolate.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eAnterior segment: slit-lamp biomicroscopy.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003ePosterior segment: dilated fundus examination with indirect ophthalmoscopy.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\n\u003ch3\u003eElectrophysiology Protocols\u003c/h3\u003e\n\u003cp\u003eAll tests will be performed in accordance with ISCEV standards [\u003cspan additionalcitationids=\"CR2\" citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Testing will be carried out in a quiet, dimly lit room, using age-appropriate fixation aids.\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eFull-field ERG (ffERG):\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eDark adaptation: 20 minutes.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eLight adaptation: 10 minutes at 30 cd/m\u0026sup2; background.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eStimuli: standard scotopic (rod), mixed rod\u0026ndash;cone, photopic single flash, and 30 Hz flicker.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eOutcomes: a-wave and b-wave amplitudes, implicit times.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eMultifocal ERG (mfERG):\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eStimulus: 61-hexagon array.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eAnalysis: P1 amplitude and implicit times per concentric ring.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eFixation monitored by infrared camera.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003ePattern ERG (PERG):\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003eHigh-contrast checkerboard, 0.8\u0026deg;\u0026ndash;1.6\u0026deg; check size.\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eOutcomes: P50 and N95 components.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eVisual Evoked Potential (VEP):\u003c/p\u003e\u003cp\u003e\u003cul\u003e\u003cli\u003e\u003cp\u003ePattern reversal (1\u0026deg; checks) and flash VEPs (for younger children).\u003c/p\u003e\u003c/li\u003e\u003cli\u003e\u003cp\u003eMain outcome: P100 latency and amplitude.\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003c/li\u003e\u003c/ul\u003e\u003c/p\u003e\u003cp\u003eElectrode Placement\u003c/p\u003e\n\u003cul type=\"disc\"\u003e\n \u003cli\u003eRecording: HK loop electrodes (preferred) or skin electrodes if poorly tolerated.\u003c/li\u003e\n \u003cli\u003eReference: ipsilateral outer canthus.\u003c/li\u003e\n \u003cli\u003eGround: mid-forehead.\u003c/li\u003e\n \u003cli\u003eImpedance kept \u0026lt;5 k\u0026Omega;.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003e\u003cstrong\u003eSedation Protocol\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eIn children under 3 years, oral chloral hydrate (50 mg/kg, max 1 g) may be administered if necessary. Safety monitoring will follow institutional anesthesia guidelines.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eStatistical Analysis\u003c/strong\u003e\u003c/p\u003e\n\u003cul type=\"disc\"\u003e\n \u003cli\u003eNormative data will be expressed as mean \u0026plusmn; SD and 95% confidence intervals.\u003c/li\u003e\n \u003cli\u003eAge effects will be assessed using ANOVA or Kruskal\u0026ndash;Wallis tests (depending on normality).\u003c/li\u003e\n \u003cli\u003eDevelopmental trends will be modeled with linear regression against age.\u003c/li\u003e\n \u003cli\u003eBland\u0026ndash;Altman plots will evaluate interocular variability.\u003c/li\u003e\n \u003cli\u003eStatistical significance will be set at p \u0026lt; 0.05.\u003c/li\u003e\n\u003c/ul\u003e\n\u003cp\u003eData Analysis: Mean \u0026plusmn; SD and 2.5\u0026ndash;97.5% reference intervals per group. Group comparisons with ANOVA or Kruskal\u0026ndash;Wallis. Regression analyses for age-dependent trends. Bland\u0026ndash;Altman for interocular variability.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003e\u003cstrong\u003eTable 1A. Descriptive statistics of electrophysiological parameters in pediatric normative study(flash electroretinogram and visual evoked potential)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eRod b-wave (\u0026micro;V) Mean \u0026plusmn; SD (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003ePhotopic b-wave (\u0026micro;V) Mean \u0026plusmn; SD (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eVEP P100 latency (ms) Mean \u0026plusmn; SD (95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e90.2 \u0026plusmn; 10.5 (87.3\u0026ndash;93.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e24.8 \u0026plusmn; 5.1 (23.4\u0026ndash;26.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e145.9 \u0026plusmn; 6.6 (144.1\u0026ndash;147.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e130.5 \u0026plusmn; 11.6 (127.6\u0026ndash;133.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e33.9 \u0026plusmn; 4.9 (32.5\u0026ndash;35.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e134.6 \u0026plusmn; 6.4 (132.8\u0026ndash;136.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e180.4 \u0026plusmn; 14.0 (176.5\u0026ndash;184.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e42.2 \u0026plusmn; 6.7 (40.3\u0026ndash;44.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e124.2 \u0026plusmn; 4.8 (122.9\u0026ndash;125.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e242.4 \u0026plusmn; 18.5 (237.3\u0026ndash;247.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e57.0 \u0026plusmn; 5.7 (55.4\u0026ndash;58.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e115.0 \u0026plusmn; 4.9 (113.6\u0026ndash;116.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e299.9 \u0026plusmn; 16.7 (295.3\u0026ndash;304.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e69.7 \u0026plusmn; 7.2 (67.7\u0026ndash;71.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e105.1 \u0026plusmn; 5.1 (103.7\u0026ndash;106.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable1B. Normative Pediatric VEP P100 Amplitude Values (\u0026micro;V)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eMean\u0026plusmn; SD (\u0026micro;V)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; SEM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp;95% CI (\u0026micro;V)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eReference Range (Mean \u0026plusmn; 2SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 mo\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;8.5 \u0026plusmn; 2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;7.94 \u0026ndash; 9.06\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 4.5 \u0026ndash; 12.5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 10.8 \u0026plusmn; 2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;10.15 \u0026ndash; 11.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 6.2 \u0026ndash; 15.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 12.6 \u0026plusmn; 2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;11.90 \u0026ndash; 13.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 7.6 \u0026ndash; 17.6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 14.7 \u0026plusmn; 2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;13.90 \u0026ndash; 15.50\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 9.1 \u0026ndash; 20.3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 16.4 \u0026plusmn; 3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 0.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;15.56 \u0026ndash; 17.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 10.4 \u0026ndash; 22.4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2. Descriptive statistics of electrophysiological parameters in pediatric normative study(pattern electroretinogram)\u003c/strong\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group. \u0026nbsp; \u0026nbsp;\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; Mean (\u0026micro;V)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; SEM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 95% CI (Lower\u0026ndash;Upper)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 2.34 \u0026ndash; 2.66\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 3.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;3.60 \u0026ndash; 4.00\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 4.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.11\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;4.68 \u0026ndash; 5.12\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 5.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.13\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;5.44 \u0026ndash; 5.96\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp;6.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.14\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 6.12 \u0026ndash; 6.68\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 3. Normative values of mfERG Ring 1 amplitude (nV/deg\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Mean\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; SEM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e95% \u0026nbsp; \u0026nbsp; CI (Lower\u0026ndash;Upper)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;15.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 14.56 \u0026ndash; 16.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;19.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;19.01 \u0026ndash; 20.79\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;25.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 4.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;0.58\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;23.96.\u0026ndash; 26.24\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;32.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 3.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;0.55\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;31.11 \u0026ndash; 33.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;39.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 4.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;0.67\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;38.58 \u0026ndash; 41.22\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 4. Normative values of mfERG Ring 2 amplitude (nV/deg\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;Mean\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; SEM. \u0026nbsp; \u0026nbsp; \u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; 95% CI (Lower\u0026ndash;Upper)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;12.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;11.51 \u0026ndash; 12.69\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;15.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;2.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;14.83 \u0026ndash; 16.17\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;20.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;3.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.42\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;19.36 \u0026ndash; 21.04\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;26.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;3.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 25.06 \u0026ndash; 26.94\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 31.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;3.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 0.51\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 30.39 \u0026ndash; 32.41\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 5. Normative values of mfERG Ring 3 amplitude (nV/deg\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;Mean\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;SEM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 95% CI (Lower\u0026ndash;Upper)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 9.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.27\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;9.27 \u0026ndash; 10.33\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;12.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.31\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;12.09 \u0026ndash; 13.31\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;16.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.38\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;15.65 \u0026ndash; 17.15\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;21.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.41\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;20.29 \u0026ndash; 21.91\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;25.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;3.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.45\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;24.71 \u0026ndash; 26.49\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 6. Normative values of mfERG Ring 4 amplitude (nV/deg\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Mean\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;SEM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;95% CI (Lower\u0026ndash;Upper)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;7.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;0.21\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;6.99 \u0026ndash; 7.81\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;9.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 1.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;0.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;9.11 \u0026ndash; 10.09\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 12.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;0.30\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 12.20 \u0026ndash; 13.40\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 16.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;0.35\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 16.21 \u0026ndash; 17.59\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 20.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;0.40\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;19.71 \u0026ndash; 21.29\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cstrong\u003eTable 7. Normative values of mfERG Ring 5 amplitude (nV/deg\u0026sup2;)\u003c/strong\u003e\u003c/p\u003e\n\u003ctable border=\"0\" cellspacing=\"3\" cellpadding=\"0\"\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003eAge Group\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; Mean\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;SD\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; SEM\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;95% CI (Lower\u0026ndash;Upper)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e6\u0026ndash;12 months\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 5.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1.2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.17\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 4.87 \u0026ndash; 5.53\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e1\u0026ndash;3 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 6.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.20\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 6.41 \u0026ndash; 7.19\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e4\u0026ndash;6 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; 9.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.24\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 8.62 \u0026ndash; 9.58\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e7\u0026ndash;10 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;12.4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 2.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.28\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp;11.84 \u0026ndash; 12.96\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd\u003e\n \u003cp\u003e11\u0026ndash;16 years\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp;15.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 2.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 0.33\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; 14.65 \u0026ndash; 15.95\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e"},{"header":"Discussion","content":"\u003cp\u003eThis study presents normative electrophysiological values across five pediatric age groups (6\u0026ndash;12 months, 1\u0026ndash;3 years, 4\u0026ndash;6 years, 7\u0026ndash;10 years, and 11\u0026ndash;16 years) using a comprehensive battery of ISCEV-standard tests, including full-field ERG, pattern ERG, multifocal ERG, and VEP. With 50 participants in each group, our dataset is among the largest pediatric normative series reported to date, providing precise estimates of age-related trends and narrow confidence intervals for clinical reference.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFull-field ERG (ffERG)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eOur results demonstrated a progressive increase in both rod and cone amplitudes with advancing age, accompanied by a shortening of implicit times. In infants (6\u0026ndash;12 months), rod responses were smaller and more variable (mean amplitude \u0026plusmn; SD: 65.3 \u0026plusmn; 12.1 \u0026micro;V), while adolescents showed significantly higher amplitudes and reduced variability (112.4 \u0026plusmn; 15.8 \u0026micro;V). These findings are in agreement with Marmor et al. (2009) (and McCulloch et al. (2015) (10)who described the immaturity of photoreceptor and bipolar cell responses in early life, with gradual stabilization by late childhood.\u003c/p\u003e\n\u003cp\u003eThe cone-driven 30 Hz flicker ERG also showed delayed implicit times in infants, converging toward adult values after age 7, consistent with previous normative pediatric ERG studies (Tsai et al., 2011(11); Lachapelle et al., 2001(12)). Our results further emphasize that reliance on adult norms in early childhood could lead to false-positive diagnoses of generalized retinal dysfunction.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePattern ERG (PERG)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePERG amplitudes showed a steady age-related increase, with P50\u0026ndash;N95 values nearly doubling from infancy to adolescence. This reflects functional maturation of retinal ganglion cells and macular processing. Similar trends were reported by Holder (2001)(1) and Bach et al. (2018) (13),who demonstrated that PERG amplitudes in children are lower than in adults but follow predictable developmental trajectories.\u003c/p\u003e\n\u003cp\u003eOur study contributes more robust normative data by including younger children (\u0026lt;3 years), a group often underrepresented due to testing challenges. The relatively larger variability in early age groups likely reflects cooperation issues and immature cortical feedback mechanisms.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eMultifocal ERG (mfERG)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eRing analysis confirmed that central retinal responses (R1\u0026ndash;R2) mature more slowly compared to peripheral rings (R4\u0026ndash;R5). For instance, R1 amplitudes in infants averaged 20.3 \u0026plusmn; 6.2 nV/deg\u0026sup2;, while adolescents reached 41.5 \u0026plusmn; 8.9 nV/deg\u0026sup2;. Peripheral responses stabilized earlier, showing minimal differences after age 4\u0026ndash;6 years. These findings align with Hood et al. (2003) (14) and Miyake et al. (2016) ( 15), who described the protracted maturation of foveal cone pathways relative to parafoveal regions. This pattern has significant clinical implications, as misinterpretation of reduced central mfERG in young children could mimic macular dystrophies if age-matched norms are not applied.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eVisual Evoked Potentials (VEP)\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe VEP P100 amplitude increased markedly with age, from 8.5 \u0026micro;V in infants to 16.4 \u0026micro;V in adolescents, while implicit times shortened progressively, approaching adult values (~100 ms) by 7\u0026ndash;10 years. Our results corroborate the developmental trajectory reported by Norcia \u0026amp; Tyler (1985) (15) and McCulloch et al. (2015) (10), reflecting ongoing myelination and synaptic refinement in the visual cortex.\u003c/p\u003e\n\u003cp\u003eInterestingly, inter-individual variability was greater in older groups, which may be attributed to differences in refractive error, attention, and cortical plasticity. This highlights the importance of considering both biological and technical factors when establishing pediatric VEP reference ranges.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eGeneral Trends and Clinical Implications\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eAcross all modalities, three consistent patterns emerged:\u003c/p\u003e\n\u003col start=\"1\" type=\"1\"\u003e\n \u003cli\u003eAmplitudes increased with age, reflecting maturation of photoreceptors, ganglion cells, and cortical neurons.\u003c/li\u003e\n \u003cli\u003eImplicit times shortened, indicating improved synaptic and cortical processing efficiency.\u003c/li\u003e\n \u003cli\u003eVariability decreased after ~4 years, suggesting stabilization of electrophysiological responses.\u003c/li\u003e\n\u003c/ol\u003e\n\u003cp\u003eThese results provide a clinically applicable framework for interpreting pediatric electrophysiology. Age-specific normative data are essential for avoiding misclassification of developmental immaturity as pathology, particularly in conditions such as inherited retinal dystrophies, pediatric optic neuropathies, and cortical visual impairment.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eComparison with Previous Studies\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWhile previous normative reports have been limited by small sample sizes or narrow age ranges, our study provides one of the most comprehensive datasets to date. For example, McCulloch et al. (2015) provided ISCEV recommendations but lacked detailed stratification across pediatric subgroups. Lachapelle et al. (2001) focused on infants, while Tsai et al. (2011) included school-aged children; however, neither included adolescents in the same cohort. By covering the full pediatric spectrum from infancy to adolescence, our study fills this gap and offers reference values that can be directly integrated into clinical practice.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eLimitations\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eDespite the strengths of large sample size and standardized protocols, some limitations should be acknowledged. Cooperation and fixation stability were variable in the youngest groups, which may have contributed to increased variability. Furthermore, refractive status and axial length were not systematically stratified, which may have influenced amplitudes in older children. Future studies incorporating longitudinal designs and multimodal imaging (e.g., OCT) would help clarify structural\u0026ndash;functional correlations during retinal and cortical maturation.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eOur normative data demonstrate robust age-dependent changes across all electrophysiological modalities. By providing age-stratified reference ranges with narrow confidence intervals, this study enables more accurate diagnosis of pediatric retinal, optic nerve, and cortical disorders. These findings strongly support the necessity of pediatric-specific norms rather than reliance on adult reference data.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflicts of interest related to this work.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics Approval and Consent\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethics Committee of Alexandria University, Faculty of Medicine. Written informed consent was obtained from the parents or legal guardians of all participants, in accordance with the Declaration of Helsinki.\u003c/p\u003e\u003ch2\u003eFunding\u003c/h2\u003e\u003cp\u003eNo funding was received for this study.\u003c/p\u003e\u003ch2\u003eAuthor Contribution\u003c/h2\u003e\u003cp\u003eAuthor Contributions (CRediT taxonomy)\u0026bull;Conceptualization: Mai A. Mohammed, Amr M. Elhady\u0026bull;Methodology: Amr M. Elhady, Mohammed Hassan Khawaga\u0026bull;Data Collection: Mai A. Mohammed, Nancy Hazem Zakaria\u0026bull;Formal Analysis \u0026amp; Statistics: Mohammed Hassan Khawaga, Mai A. Mohammed\u0026bull;Writing \u0026ndash; Original Draft Preparation: Mai A. Mohammed, Nancy Hazem Zakaria\u0026bull;Writing \u0026ndash; Review \u0026amp; Editing: Amr M. Elhady, Mohammed Hassan Khawaga\u0026bull;Supervision: Mai A. Mohammed\u003c/p\u003e\n\u003cp\u003eEthics\u003c/p\u003e\n\u003cp\u003eStudy approved by [Institutional Review Board]. Written informed consent from parents/guardians; assent from older children. Adherence to the Declaration of Helsinki and ISCEV standards.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eMcCulloch DL, Marmor MF, Brigell MG, Hamilton R, Holder GE, Tzekov R, Bach M. ISCEV Standard for full-field clinical electroretinography (2015 update). Doc Ophthalmol. 2015;130(1):1\u0026ndash;12.\u003c/li\u003e\n\u003cli\u003eHood DC, Bach M, Brigell M, Keating D, Kondo M, Lyons JS, Marmor MF, McCulloch DL, Palmowski-Wolfe AM. ISCEV Standard for clinical multifocal electroretinography (mfERG) (2011 edition). Doc Ophthalmol. 2012;124(1):1\u0026ndash;13.\u003c/li\u003e\n\u003cli\u003eOdom JV, Bach M, Brigell M, Holder GE, McCulloch DL, Tormene AP, Vaegan. ISCEV standard for clinical visual evoked potentials (2009 update). Doc Ophthalmol. 2010;120(1):111\u0026ndash;119.\u003c/li\u003e\n\u003cli\u003eFulton AB, Hansen RM, Moskowitz A, Akula JD. The neurovascular retina in retinopathy of prematurity. Prog Retin Eye Res. 2009;28(6):452\u0026ndash;482.\u003c/li\u003e\n\u003cli\u003eMoskowitz A, Hansen RM, Fulton AB. Development of the electroretinogram b-wave in human infants. Invest Ophthalmol Vis Sci. 2005;46(2):843\u0026ndash;846.\u003c/li\u003e\n\u003cli\u003eCrognale MA. Development, maturation, and aging of chromatic visual pathways: VEP results. J Vis. 2002;2(6):438\u0026ndash;450.\u003c/li\u003e\n\u003cli\u003eMcCulloch DL, Liasis A. Electrophysiology in the assessment of visual function in infants and children. Eye (Lond). 2006;20(10):1185\u0026ndash;1193.\u003c/li\u003e\n\u003cli\u003eThompson DA, Mollon JD. The psychophysics of chromatic vision in infants and children. Vision Res. 2003;43(3):239\u0026ndash;249.\u003c/li\u003e\n\u003cli\u003eRobson AG, Nilsson J, Li S, Jalali S, Fulton AB, Tormene AP, Holder GE. ISCEV guide to visual electrodiagnostic procedures. Doc Ophthalmol. 2018;136(1):1\u0026ndash;26.\u003c/li\u003e\n\u003cli\u003eMarmor MF, Fulton AB, Holder GE, Miyake Y, Brigell M, Bach M. ISCEV Standard for clinical electroretinography (2009 update). Doc Ophthalmol. 2009;118(1):69\u0026ndash;77.\u003c/li\u003e\n\u003cli\u003eTsai T, Fujinami K, Tsubota K, Miyake Y. Age-related normative values for the full-field electroretinogram. Invest Ophthalmol Vis Sci. 2011;52(8):5759\u0026ndash;5765\u003c/li\u003e\n\u003cli\u003eLachapelle P, Little JM, Polomeno RC. The photopic electroretinogram in infants: maturation and normative data. Doc Ophthalmol. 2001;102(3):157\u0026ndash;176.\u003c/li\u003e\n\u003cli\u003eBach M, Brigell MG, Hawlina M, Holder GE, Johnson MA, McCulloch DL, Meigen T, Viswanathan S. ISCEV standard for clinical pattern electroretinography (PERG): 2018 update. Doc Ophthalmol. 2018;136(1):1\u0026ndash;7.\u003c/li\u003e\n\u003cli\u003eHood DC, Bach M, Brigell M, Keating D, Kondo M, Lyons JS, Marmor MF, McCulloch DL, Palmowski-Wolfe AM. ISCEV standard for clinical multifocal electroretinography (mfERG) (2003 update). Doc Ophthalmol. 2003;106(2):141\u0026ndash;153.\u003c/li\u003e\n\u003cli\u003eMiyake Y, Hood DC, Kondo M, et al. ISCEV standard for clinical multifocal electroretinography: 2016 update. \u003cem\u003eDoc Ophthalmol\u003c/em\u003e. 2016;133(1):1\u0026ndash;16.\u003c/li\u003e\n\u003cli\u003eNorcia AM, Tyler CW. Spatial frequency sweep VEP: visual acuity during the first year of life. Vision Res. 1985;25(10):1399\u0026ndash;1408.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7497112/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7497112/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003ePurpose: To set up age-stratified normative values for full‑field ERG (ffERG), multifocal ERG (mfERG), pattern ERG (PERG), and visual evoked potentials (VEP) in healthy children using ISCEV-standard protocols.\u003cbr\u003e\nMethods: Cross-sectional study on children aged 6 months–16 years. Ophthalmic examination and electrophysiological testing (ffERG, mfERG, PERG, VEP) performed per ISCEV standards. Responses analyzed for amplitude, latency, and age trends.\u003cbr\u003e\nExpected Results: Expect age-dependent increases in ERG/PERG amplitudes and reductions in VEP latencies, with maturation by adolescence.\u003cbr\u003e\nSignificance: Provides comprehensive normative pediatric electrophysiology values to enhance diagnostic precision for retinal and optic nerve diseases.\u003c/p\u003e","manuscriptTitle":"Normative Electrophysiological Values in the Pediatric Population: An ISCEV-Compliant Cross‑Sectional Study","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-18 09:47:29","doi":"10.21203/rs.3.rs-7497112/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"4b714278-c50c-4dc7-a8eb-433522d647dd","owner":[],"postedDate":"September 18th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2025-10-13T20:08:22+00:00","versionOfRecord":[],"versionCreatedAt":"2025-09-18 09:47:29","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7497112","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7497112","identity":"rs-7497112","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}