1
|
Yan W, Chen Y, Chen X, Ye Q, Wang Y, Jiang C, Zheng X, Wang Y, Chen M. Diagnosis of keratoconus in a young male by electrophysiological test findings: A case report. Medicine (Baltimore) 2022; 101:e29351. [PMID: 35801804 PMCID: PMC9259123 DOI: 10.1097/md.0000000000029351] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
RATIONALE The purpose of this report was to describe the diagnostic process of a case of keratoconus (KCN) after electrophysiological examination. PATIENT CONCERNS A 23-year-old male army officer presented with decreased visual acuity (VA) in the left eye for 5 months. Best-corrected VA was 20/20 in the right eye and 20/300 in the left eye. The cornea and lens were clear in both eyes with a normal anterior chamber. No specific abnormalities were found on fundus photography, optical coherence tomography, fundus fluorescein angiography (FFA), indocyanine green angiography (ICGA), or full-field electroretinography (ffERG) of both eyes. Pattern visual-evoked potentials (PVEP) detected a reduced amplitude and delayed peak time of the P100-wave in both eyes, which was more severe in the left eye. The amplitude and peak time of the P2-wave in flash VEP (FVEP) were comparable in both eyes and were within the normal ranges. DIAGNOSIS Corneal topography was performed, and KCN was diagnosed by the presence of an asymmetrical bowtie pattern in both eyes, which was worse in the left eye. INTERVENTIONS Transepithelial corneal collagen cross-linking was performed. OUTCOMES The BCVA of both eyes remained stable after treatment at follow-up. LESSONS KCN should be suspected in cases of unimproved VA and significant irregular stigmatism, while no obvious lesions exist in other parts of the eyes. The evidence of lesion location by electrophysiological examinations could sometimes be of favor in diagnosing KCN.
Collapse
Affiliation(s)
- Weiming Yan
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Yanjin Chen
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Xiaohong Chen
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Qian Ye
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Yutong Wang
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Chuan Jiang
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Xiangrong Zheng
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Yunpeng Wang
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| | - Meizhu Chen
- Department of Ophthalmology, The 900th Hospital of Joint Logistic Support Force, PLA (Clinical Medical College of Fujian Medical University, Dongfang Hospital Affiliated to Xiamen University), Fuzhou, China
| |
Collapse
|
2
|
Dettoraki M, Droutsas K, Lazaridis A, Moschos MM. Evaluation of macular function and morphology following accelerated collagen cross-linking in progressive keratoconus. Eur J Ophthalmol 2022; 32:2547-2553. [PMID: 35450449 DOI: 10.1177/11206721221094880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE To assess any changes in macular function and morphology in patients with progressive keratoconus undergoing accelerated corneal cross-linking (CXL). METHODS This prospective case series included 9 eyes of 8 patients with progressive keratoconus undergoing CXL using a high intensity accelerated protocol (9 mW/cm2 for 14 min) with a total surface dose of 7.5 J/cm2. Visual acuity assessment, slit lamp biomicroscopy, dilated fundoscopy, corneal tomography, multifocal electroretinography (mfERG) and spectral domain optical coherence tomography scan were performed at baseline, 2 weeks and 6 weeks postoperatively. RESULTS Uncorrected and corrected distance visual acuity did not change significantly at 2 weeks and 6 weeks following accelerated CXL compared to baseline. Retinal response density (RRD) of mfERG significantly decreased at 2 weeks postoperatively compared to baseline (p = 0.008) but did not differ from the baseline value at 6 weeks postoperatively in the fovea (ring 1) (p = 0.95). Similarly, P1 latency significantly decreased at 2 weeks (p = 0.04) but did not change at 6 weeks (p = 1.00) postoperatively compared to baseline in the fovea. No changes in RRD or P1 latency were observed in the retinal rings surrounding the fovea (rings 2 to 5). Central foveal thickness did not change at 2 weeks and 6 weeks postoperatively compared to baseline (p = 0.53 and p = 0.93, respectively). CONCLUSIONS A short-term reversible decrease in macular electrical activity without any structural changes seems to occur after accelerated CXL in patients with progressive keratoconus. The return of macular response to the preoperative values shows the safety of the CXL protocol.
Collapse
Affiliation(s)
- M Dettoraki
- First Department of Ophthalmology, Medical School, 393206National and Kapodistrian University of Athens, Athens, Greece
| | - K Droutsas
- First Department of Ophthalmology, Medical School, 393206National and Kapodistrian University of Athens, Athens, Greece.,Department of Ophthalmology, 98594Philipps University of Marburg, Marburg, Germany
| | - A Lazaridis
- Department of Ophthalmology, 98594Philipps University of Marburg, Marburg, Germany
| | - M M Moschos
- First Department of Ophthalmology, Medical School, 393206National and Kapodistrian University of Athens, Athens, Greece
| |
Collapse
|
3
|
Entchev E, Antonelli S, Mauro V, Cimbolini N, Jantzen I, Roussey A, Germain JM, Zhang H, Luccarrini JM, Lacombe O, Young SP, Feraille L, Tallandier M. MPS VI associated ocular phenotypes in an MPS VI murine model and the therapeutic effects of odiparcil treatment. Mol Genet Metab 2022; 135:143-153. [PMID: 34417096 DOI: 10.1016/j.ymgme.2021.07.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 07/19/2021] [Accepted: 07/23/2021] [Indexed: 01/10/2023]
Abstract
Maroteaux - Lamy syndrome (mucopolysaccharidosis type VI, MPS VI) is a lysosomal storage disease resulting from insufficient enzymatic activity for degradation of the specific glycosaminoglycans (GAG) chondroitin sulphate (CS) and dermatan sulphate (DS). Among the most pronounced MPS VI clinical manifestations caused by cellular accumulation of excess CS and DS are eye disorders, in particular those that affect the cornea. Ocular manifestations are not treated by the current standard of care, enzyme replacement therapy (ERT), leaving patients with a significant unmet need. Using in vitro and in vivo models, we previously demonstrated the potential of the β-D-xyloside, odiparcil, as an oral GAG clearance therapy for MPS VI. Here, we characterized the eye phenotypes in MPS VI arylsulfatase B deficient mice (Arsb-) and studied the effects of odiparcil treatment in early and established disease models. Severe levels of opacification and GAG accumulation were detected in the eyes of MPS VI Arsb- mice. Histological examination of MPS VI Arsb- eyes showed an aggregate of corneal phenotypes, including reduction in the corneal epithelium thickness and number of epithelial cell layers, and morphological malformations in the stroma. In addition, colloidal iron staining showed specifically GAG accumulation in the cornea. Orally administered odiparcil markedly reduced GAG accumulation in the eyes of MPS VI Arsb- mice in both disease models and restored the corneal morphology (epithelial layers and stromal structure). In the early disease model of MPS VI, odiparcil partially reduced corneal opacity area, but did not affect opacity area in the established model. Analysis of GAG types accumulating in the MPS VI Arsb- eyes demonstrated major contribution of DS and CS, with some increase in heparan sulphate (HS) as well and all were reduced with odiparcil treatment. Taken together, we further reveal the potential of odiparcil to be an effective therapy for eye phenotypes associated with MPS VI disease.
Collapse
Affiliation(s)
| | - Sophie Antonelli
- Iris Pharma, Les Nertiéres, Allée Hector Pintus, La Gaude 06610, France
| | - Virginie Mauro
- Iris Pharma, Les Nertiéres, Allée Hector Pintus, La Gaude 06610, France
| | - Nicolas Cimbolini
- Iris Pharma, Les Nertiéres, Allée Hector Pintus, La Gaude 06610, France
| | | | | | | | - Haoyue Zhang
- Duke University Health System Biochemical Genetics Lab, Durham, NC, USA
| | | | | | - Sarah P Young
- Duke University Health System Biochemical Genetics Lab, Durham, NC, USA; Division of Medical Genetics, Department of Pediatrics, Duke School of Medicine, Durham, NC, USA
| | - Laurence Feraille
- Iris Pharma, Les Nertiéres, Allée Hector Pintus, La Gaude 06610, France
| | | |
Collapse
|
4
|
Hashemi H, Heirani M, Ambrósio R, Hafezi F, Naroo SA, Khorrami-Nejad M. The link between Keratoconus and posterior segment parameters: An updated, comprehensive review. Ocul Surf 2021; 23:116-122. [PMID: 34890805 DOI: 10.1016/j.jtos.2021.12.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 11/26/2021] [Accepted: 12/06/2021] [Indexed: 02/07/2023]
Abstract
Keratoconus (KCN) has been typically known as a disorder with effects limited to the cornea. Because of this viewpoint, less attention has been devoted to its effects on the posterior segment structures. We aimed to provide a comprehensive review of the literature to understand the potential link between KCN and posterior segment structures and their functions. It is clear from the extensive evidence in the literature that KCN can be associated with morphological and functional changes in different parts of the posterior segment. It is worth noting that anatomical changes have been not only noted in several layers of the retina but also in the optic nerve head and the choroid. Several mechanisms have been proposed to explain this observation, including incidents induced by oxidative stress in keratoconic corneas and retinal adaptions to the distorted image that lands on the retina. Consequently, when KCN has been diagnosed, it seems practical to consider assessing the retinal and choroidal profile using optical coherence tomography and potentially functional abnormalities through electrophysiology procedures.
Collapse
Affiliation(s)
- Hassan Hashemi
- Noor Ophthalmology Research Center, Noor Eye Hospital, Tehran, Iran
| | - Mohsen Heirani
- Translational Ophthalmology Research Center, Farabi Eye Hospital, Tehran University of Medical Sciences, Tehran, Iran.
| | - Renato Ambrósio
- Department of Ophthalmology, Federal University of the State of Rio de Janeiro, Brazil
| | - Farhad Hafezi
- ELZA Institute, Dietikon, Zurich, Switzerland; Faculty of Medicine, University of Geneva, Geneva, Switzerland
| | - Shehzad A Naroo
- College of Health and Life Sciences, Aston University, Birmingham, B4 7ET, UK
| | | |
Collapse
|
5
|
Hong IH, Chang IB, Jeon GS, Han JR. Evaluation of acute central serous chorioretinopathy using enhanced depth imaging OCT and multifocal electroretinography. Ophthalmologica 2021; 245:25-33. [PMID: 33957632 DOI: 10.1159/000516097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 03/17/2021] [Indexed: 11/19/2022]
Affiliation(s)
- In Hwan Hong
- Department of Ophthalmology, Dongtan Sacred Heart Hospital, Hallym University Medical Center, Hwaseong-si, Republic of Korea
| | | | - Gang Seok Jeon
- Dasan Samsung Bright Eye Clinic, Gyeonggi-do, Republic of Korea
| | - Jae Ryong Han
- Department of Ophthalmology, Dongtan Sacred Heart Hospital, Hallym University Medical Center, Hwaseong-si, Republic of Korea
| |
Collapse
|
6
|
Amorim-de-Sousa A, Macedo-de-Araújo R, Fernandes P, Queirós A, González-Méijome JM. Multifocal Electroretinogram in Keratoconus Patients without and with Scleral Lenses. Curr Eye Res 2021; 46:1732-1741. [PMID: 33823736 DOI: 10.1080/02713683.2021.1912781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Purpose: To investigate changes in the multifocal electroretinogram (mfERG) response in eyes with keratoconus when corrected with scleral lenses (SL) compared with the best correction in glasses.Methods: The mfERG responses in 10 eyes with keratoconus were recorded with the best correction using both a trial frame (baseline) and a hexafocon A SL using an electrophysiological diagnostic system. Electrophysiologic measurements were performed with the pupils fully dilated with instillation of 1% phenylephrine. The implicit time (milliseconds), amplitude (nV), and response density (nV/deg2) of the peaks (N1, P1, and N2) were analyzed for the total mfERG response, six rings and four quadrants of the retina, and compared between the two conditions.Results: All eyes had a significant improvement in visual quality with the SL compared with baseline (mean differences, 0.26 ± 0.17 and 0.22 ± 0.13 logarithm of the minimum angle of resolution for high- and low-contrast visual acuity, respectively). The peaks implicit times of the mfERG responses did not show significant differences (p > .05). The P1 amplitude decreased in all the retinal areas with the SL. Only the total retinal response and the nasal quadrants reached significance (p ≤ 0.044). The P1 response density in ring 1 was on average higher with the SL, but not significantly so. The decline in P1 response density from the center to the periphery was more abrupt with the SL, and was more similar to the response density distribution of a typical subject, without a corneal pathology.Conclusions: mfERG did not show any change associated with retinal disease in young patients with keratoconus. Although the improved visual performance was not associated with changes in the mfERG response, the correction of irregular astigmatism with the SL helps exclude the optical effect induced by keratoconus.
Collapse
Affiliation(s)
- Ana Amorim-de-Sousa
- Clinical & Experimental Optometry Research Lab (CEORLab), Center of Physics, University of Minho, Braga, Portugal
| | - Rute Macedo-de-Araújo
- Clinical & Experimental Optometry Research Lab (CEORLab), Center of Physics, University of Minho, Braga, Portugal
| | - Paulo Fernandes
- Clinical & Experimental Optometry Research Lab (CEORLab), Center of Physics, University of Minho, Braga, Portugal
| | - António Queirós
- Clinical & Experimental Optometry Research Lab (CEORLab), Center of Physics, University of Minho, Braga, Portugal
| | - José M González-Méijome
- Clinical & Experimental Optometry Research Lab (CEORLab), Center of Physics, University of Minho, Braga, Portugal
| |
Collapse
|
7
|
Fung MMY, Choi KY, Chan HHL. The effect of simultaneous dual-focus integration on the global flash multifocal electroretinogram in the human eye. Ophthalmic Physiol Opt 2020; 41:171-178. [PMID: 33119966 DOI: 10.1111/opo.12751] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 09/10/2020] [Indexed: 01/01/2023]
Abstract
PURPOSE To investigate the effect of simultaneous dual-focus (DF) on retinal activities measured by global flash multifocal electroretinogram (mfERG). METHODS Thirty adults were recruited for mfERG measurement under three conditions: in-focus (i.e., no defocus), +2.50 D DF and +7.50 D DF, administered using single vision contact lenses and DF lenses. The direct component (DC) and the induced component (IC) of the mfERG were pooled into central macular (0-8°), para-macular (8-18°) and peri-macular (18-30°) regions, and then compared across the three conditions using two-way, repeated measures ANOVA. RESULTS Simultaneous DF had a significant effect on the IC amplitude, which was significantly stronger under +7.50 D DF (p < 0.01) than for the in-focus condition, which was mostly derived from the central and para-macular regions. No significant effect was observed for the +2.50 D DF condition. CONCLUSION Under the effect of relatively strong simultaneous DF integration, the retina showed an enhanced retinal response, which originated from the inner retina. Compared with the peri-macular region, central and para-macular responses appeared to be enhanced.
Collapse
Affiliation(s)
- Mavis M Y Fung
- The Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Kai Yip Choi
- The Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China.,Laboratory of Experimental Optometry (Neuroscience), School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China
| | - Henry H L Chan
- The Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China.,Laboratory of Experimental Optometry (Neuroscience), School of Optometry, The Hong Kong Polytechnic University, Hong Kong, China.,Centre for Eye and Vision Research, Hong Kong, China
| |
Collapse
|
8
|
Miura G, Baba T, Oshitari T, Yamamoto S. Flicker electroretinograms of eyes with cataract recorded with RETeval system before and after mydriasis. Clin Ophthalmol 2018. [PMID: 29535500 PMCID: PMC5840279 DOI: 10.2147/opth.s157505] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose The aim of this study is to determine the effect of pupil size of eyes with cataracts on the flicker electroretinograms (ERGs) elicited and recorded with the RETeval system. Patients and methods Forty-one eyes of 41 patients (mean age, 76.5±7.3 years) that had grade 2 nuclear or cortical cataract without any other abnormalities were studied. Flicker ERGs were recorded before and after mydriatic drops instillation. The ERGs were elicited by the white light delivered at the frequency of 28.3 Hz and intensities of 2, 8, and 32 Td-s. The amplitudes and the implicit times of the flicker ERGs before and after mydriasis were compared. Results There were no significant differences between the amplitudes before and after mydriasis (P=0.35, 2 Td-s; P=0.31, 8 Td-s; P=0.50, 32 Td-s). There were also no significant differences between the implicit times before and after mydriasis (P=0.86, 2 Td-s; P=0.98, 8 Td-s; P=0.95, 32 Td-s). The mean amplitudes and implicit times of the nuclear and cortical cataracts groups before the mydriasis were also not significantly different from those after mydriasis for all stimulus intensities. Conclusion The lack of significant differences in the amplitudes and the implicit times of the flicker ERG of cataractous eyes before and after mydriasis indicated that the RETeval flicker ERGs in cataractous eyes is less affected by the pupil diameter. With our earlier study, it was assumed that the effect of cataracts on the RETeval flicker ERGs was due to the opacity of the crystalline lens, and the influence of the cataract would not be reduced or increased by mydriasis.
Collapse
Affiliation(s)
- Gen Miura
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Takayuki Baba
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Toshiyuki Oshitari
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba, Japan
| | - Shuichi Yamamoto
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Chiba, Japan
| |
Collapse
|
9
|
Flicker electroretinograms recorded with mydriasis-free RETeval system before and after cataract surgery. Eye (Lond) 2017. [PMID: 28622319 DOI: 10.1038/eye.2017.110] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
PurposeThe purpose of this study is to compare the amplitudes and peak times of the flicker electroretinograms (ERGs) recorded before and after cataract surgery with the RETeval system (LKC Technologies, Gaithersburg, MD, USA) from eyes without dilation.Patients and methodsThirty-two eyes of 32 patients (77.3±6.5 years) that had grade 2 Emery-Little nuclear or cortical cataract without any other abnormalities were studied. Flicker ERGs were recorded with the RETeval system under mydriatic-free conditions. Skin electrodes were used to pick-up the ERGs that were elicited by white light delivered at a rate of 28.3 Hz and intensity of 2, 8, and 32 Td-s. The amplitudes and peak times of the flicker ERGs before and after cataract surgery were compared.ResultsThe mean amplitudes were significantly increased after the removal of the cataractous lenses at the three stimulus intensities (2 Td-s, P<0.0001; 8 Td-s, P<0.0001; and 32 Td-s, P<0.0001). The mean peak times of the flicker ERGs elicited by 2 and 8 Td-s were significantly shortened after the surgery (2 td-s, P<0.0001 and 8 td-s, P=0.0127) but not at 32 td-s (P=0.595).ConclusionsThese results indicate that the presence of cataracts will affect both the amplitudes and the peak times of the flicker ERGs even if the cataract is mild. In addition, the results indicate that as stimulus intensity increases, the peak times is less affected by a cataract. The clarity of the crystalline lens should be considered when interpreting the flicker ERGs recorded with the RETeval system.
Collapse
|
10
|
Miura G, Nakamura Y, Sato E, Yamamoto S. Effects of cataracts on flicker electroretinograms recorded with RETeval™ system: new mydriasis-free ERG device. BMC Ophthalmol 2016; 16:22. [PMID: 26944722 PMCID: PMC4779227 DOI: 10.1186/s12886-016-0200-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Accepted: 02/28/2016] [Indexed: 11/10/2022] Open
Abstract
Background The purpose of this study was to evaluate the effects of cataracts on the flicker electroretinograms (ERGs) recorded with the RETeval™ system under mydriatic-free conditions. Methods This was a retrospective study of 82 eyes of 60 patients with cataracts and 52 eyes of 38 patients who were pseudophakic. Flicker ERGs were recorded with the RETeval™ system (LKC Technologies, Gaithersburg, MD) under mydriatic-free condition with skin electrodes. Flicker ERGs were elicited by white light delivered at a frequency of 28.3 Hz and intensity of 8 Td-s. The implicit times and amplitudes of the ERGs recorded from the Grade 2 cataract, Grade 3 cataract, and pseudophakic groups were compared. Results The mean amplitude was significantly smaller in both cataract groups than the pseudophakic group (Grade 2 cataract vs pseudophakic group, P < 0.0001; Grade 3 cataract vs pseudophakic group, P < 0.0001; Grade 2 cataract vs Grade 3 cataract, P = 0.027). The mean implicit times was significantly longer in both cataract groups than the pseudophakic group (Grade 2 cataract vs pseudophakic group, P = 0.046; Grade 3 cataract vs pseudophakic group, P = 0.0004; Grade 2 cataract vs Grade 3 cataract, P = 0.0084). Conclusions The results indicate that the presence of Grade 2 or more cataracts will affect both the amplitude and the implicit time of the flicker ERGs. The presence of cataracts should be taken into consideration when interpreting the flicker ERG recorded with RETeval™.
Collapse
Affiliation(s)
- Gen Miura
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, 260-8670, Japan.
| | - Yosuke Nakamura
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, 260-8670, Japan.
| | - Eiju Sato
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, 260-8670, Japan.
| | - Shuichi Yamamoto
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, 260-8670, Japan.
| |
Collapse
|
11
|
Herbik A, Hölzl GC, Reupsch J, Hoffmann MB. Differential effects of optic media opacities on mfERGs and mfVEPs. Clin Neurophysiol 2013; 124:1225-31. [PMID: 23352815 DOI: 10.1016/j.clinph.2012.11.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2012] [Revised: 11/21/2012] [Accepted: 11/28/2012] [Indexed: 11/19/2022]
Abstract
OBJECTIVE To assess different effects of image degradation that could result from optic media opacities on multifocal retinal (mfERG) and cortical responses (mfVEP). METHODS Monocular flash-mfERGs and pattern-reversal mfVEPs were recorded. MfERG-P1 amplitudes and implicit times and mfVEP root-mean-square values (RMS) and delays were compared for different filter conditions (none, 8% luminance, 50% luminance, 50% luminance plus blur) in a total of ten participants with normal vision. RESULTS Reducing stimulus luminance down to 50% and 8% reduced mfERG amplitudes to 86% and 42%, respectively, with no significant effect on mfVEP amplitude. Implicit times were increased for mfERGs by 0.9 ms and 6.0 ms, respectively, and for mfVEPs by 1.0 ms and 6.3 ms, respectively. For '50% luminance plus blur' mfERG amplitudes were significantly reduced centrally and enhanced peripherally and delayed by 1.3 ms. MfVEPs were reduced close to noise level independent of eccentricity. CONCLUSIONS Degradation of the retinal image is a potential source of discrepancies between mfERGs and mfVEPs. Image blur suppresses the mfVEP at all locations and changes mfERG topography, resulting in a selective loss of central responses. SIGNIFICANCE Considering optic media opacities is of importance for the correct interpretation of mfERG and mfVEP recordings, particularly in elderly patients.
Collapse
Affiliation(s)
- A Herbik
- Visual Processing Laboratory, Ophthalmology, Otto-von-Guericke-University, Magdeburg, Germany
| | | | | | | |
Collapse
|
12
|
Moschos MM, Chatziralli IP, Koutsandrea C, Siasou G, Droutsas D. Assessment of the Macula in Keratoconus: An Optical Coherence Tomography and Multifocal Electroretinography Study. Ophthalmologica 2013; 229:203-207. [DOI: 10.1159/000350801] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Abstract
<b><i>Purpose:</i></b> The purpose of our study was to assess the macular thickness and the electrophysiological changes in keratoconic patients without any systemic or ocular disorders.<b><i> Methods: </i></b>64 eyes of 32 keratoconus patients as well as 60 eyes of 30 controls participated in the study. All participants underwent a complete ophthalmological examination, including best-corrected visual acuity (BCVA) assessment, color vision testing, fundus examination, intraocular pressure measurement, central foveal thickness (CFT) measurement by optical coherence tomography (OCT) scan, and multifocal-electroretinogram (mf-ERG) recording. CFT, retinal response density (RRD) and P<sub>1</sub> latency were measured. <b><i>Results:</i></b> There was no statistically significant difference between the two groups concerning CFT and P<sub>1</sub> latency in mf-ERG. The RRD in mf-ERG differed significantly between keratoconus patients and controls. Of note, BCVA was positively associated with RRD in keratoconus patients. <b><i>Conclusion:</i></b> In some cases of keratoconus, a macular dysfunction not visible ophthalmoscopically may coexist and the low visual acuity could be due not only to the corneal abnormality, but also to the photoreceptor dysfunction. As a result, the preoperative electrophysiological study of patients with keratoconus is crucial to avoid a needless corneal transplantation.
Collapse
|
13
|
Tam WK, Chan H, Brown B, Leung KW, Woo V, Yap M. Comparing the Multifocal Electroretinogram Topography before and after Cataract Surgery. Curr Eye Res 2009; 30:593-9. [PMID: 16020294 DOI: 10.1080/02713680590968565] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To investigate whether multifocal electroretinogram (mfERG) topography would be affected by nuclear cataract. METHODS Multifocal electroretinograms were recorded from 10 elderly subjects (10 eyes) with nuclear cataract of grade five (LOCS III) before and after cataract surgery (phacoemulsification). Their visual acuity before the cataract surgery was between 6/12 and 6/18. The postoperative period was from 2 to 3 months. None of the subjects had any significant eye disease apart from cataract. The mfERG responses were grouped into six concentric rings for analysis. Both the amplitudes and the latencies of N1 and P1 of first-order responses were used for analysis. RESULTS N1 amplitude only from ring 1 increased significantly after cataract surgery. P1 amplitude from ring 1 and ring 2 also increased significantly after cataract surgery. The latencies of neither N1 nor P1 from all rings changed significantly. CONCLUSIONS Nuclear cataract could affect the topography of mfERG, so clinicians should be aware of the effects of cataract when interpreting mfERG responses in cataract patients.
Collapse
Affiliation(s)
- Wing-Kin Tam
- Department of Optometry and Radiography, The Hong Kong Polytechnic University, Hong Kong
| | | | | | | | | | | |
Collapse
|
14
|
Harrison WW, Bearse MA, Ng JS, Barez S, Schneck ME, Adams AJ. Reproducibility of the mfERG between instruments. Doc Ophthalmol 2009; 119:67-78. [PMID: 19322597 PMCID: PMC2700238 DOI: 10.1007/s10633-009-9171-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2008] [Accepted: 03/03/2009] [Indexed: 11/02/2022]
Abstract
PURPOSE First, to examine both the reproducibility of the multifocal electroretinogram (mfERG) recorded on different versions of the same instrument, and the repeatability of the mfERG recorded on a single instrument using two different amplifiers. Second, to demonstrate a means by which multicenter and longitudinal studies that use more than one recording instrument can compare and combine data effectively. METHODS Three different amplifiers and two mfERG setups, one using VERIS 4.3 software (mfERG1) and another using VERIS Pro 5.2 software (mfERG2), were evaluated. A total of 73 subjects with normal vision were tested in three groups. Group 1 (n = 42) was recorded using two amplifiers in parallel on mfERG1. Group 2 (n = 52) was recorded on mfERG2 using a single amplifier. Group 3 was a subgroup of 21 subjects from groups 1 and 2 that were tested sequentially on both instruments. A fourth group of 26 subjects with diabetes were also recorded using the two parallel amplifiers on mfERG1. P1 implicit times and N1-P1 amplitudes of the 103 local first order mfERGs were measured, and the differences between the instruments and amplifiers were evaluated as raw scores and Z-scores based on normative data. Measurements of individual responses and measurements averaged over the 103 responses were analyzed. RESULTS Simultaneous recordings made on mfERG1 with the two different amplifiers showed differences in implicit times but similar amplitudes. There was a mean implicit time difference of 2.5 ms between the amplifiers but conversion to Z-scores improved their agreement. Recordings made on different days with the two instruments produced similar but more variable results, with amplitudes differing between them more than implicit times. For local response implicit times, the 95% confidence interval of the difference between instruments was approximately +/-1 Z-score (+/-0.9 ms) in either direction. For local response amplitude, it was approximately +/-1.6 Z-scores (+/-0.3 microV). CONCLUSIONS Different amplifiers can yield quite different mfERG P1 implicit times, even with identical band-pass settings. However, the reproducibility of mfERG Z-scores across recording instrumentation is relatively high. Comparison of data across systems and laboratories, necessary for multicenter or longitudinal investigations, is facilitated if raw data are converted into Z-scores based on normative data.
Collapse
Affiliation(s)
- Wendy W Harrison
- University of California Berkeley School of Optometry, 94720-2020, USA.
| | | | | | | | | | | |
Collapse
|
15
|
Lai TYY, Chan WM, Lai RYK, Ngai JWS, Li H, Lam DSC. The clinical applications of multifocal electroretinography: a systematic review. Surv Ophthalmol 2007; 52:61-96. [PMID: 17212991 DOI: 10.1016/j.survophthal.2006.10.005] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Multifocal electroretinography (mfERG) is an investigation that can simultaneously measure multiple electroretinographic responses at different retinal locations by cross-correlation techniques. mfERG therefore allows topographic mapping of retinal function in the central 40-50 degrees of the retina. The strength of mfERG lies in its ability to provide objective assessment of the central retinal function at different retinal areas within a short duration of time. Since the introduction of mfERG in 1992, mfERG has been applied in a large variety of clinical settings. This article reviews the clinical applications of mfERG based on the currently available evidence. mfERG has been found to be useful in the assessment of localized retinal dysfunction caused by various acquired or hereditary retinal disorders. The use of mfERG also enabled clinicians to objectively monitor the treatment outcomes as the changes in visual functions might not be reflected by subjective methods of assessment. By changing the stimulus, recording, and analysis parameters, investigation of specific retinal electrophysiological components can be performed topographically. Further developments and consolidations of these parameters will likely broaden the use of mfERG in the clinical setting.
Collapse
Affiliation(s)
- Timothy Y Y Lai
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, People's Republic of China
| | | | | | | | | | | |
Collapse
|
16
|
Gjörloff KW, Andréasson S, Ghosh F. mfERG in normal and lesioned rabbit retina. Graefes Arch Clin Exp Ophthalmol 2005; 244:83-9. [PMID: 15983815 DOI: 10.1007/s00417-005-0019-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2004] [Revised: 02/17/2005] [Accepted: 04/14/2005] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND To evaluate and describe the cone function in the normal and lesioned rabbit retina using the multifocal electroretinogram (mfERG). METHODS Twelve animals underwent a two-port vitrectomy with subsequent retinectomy in one eye. The area of removed retina was located in the nasal part of the visual streak, and measured approximately 1-2 disc diameters. Both eyes were investigated with mfERG preoperatively and up to 13 weeks postoperatively. A Burian-Allen bipolar contact lens with built-in infrared emitters was used to visualize the retina during the recordings. The averages of the trace array amplitudes in the lower nasal and temporal quadrants were calculated and statistically analyzed at the different time intervals. All eyes were examined histologically with hematoxylin and eosin staining. RESULTS The retina could be visualized during the mfERG examinations. Postoperatively, up to 3 weeks, amplitudes were reduced over the entire stimulated area in retinectomized eyes (2.20 microV+/-1.22 SD) as compared with preoperative examinations (3.40 microV+/-1.00 SD). After 7 weeks the amplitudes in the quadrant including the retinectomized area remained low (2.62 microV+/-1.02 SD), whereas they were higher than at earlier postoperative examinations in the lower unlesioned temporal quadrant (3.56 microV+/-0.71 SD) with a statistical difference between the quadrants. At 13 weeks this was even more pronounced. In unoperated eyes, the area corresponding to the visual streak displayed significantly higher amplitudes than the area superior to the myelinated streak, corresponding well to the cone distribution. High amplitudes were also detected in the area of the myelinated nerve fibers and optic nerve head, most likely as a result of scattering light. In histological sections, the retinectomized area had a diameter of 1-3 mm. CONCLUSIONS This study shows that the mfERG technique can be used as a tool in experimental retinal research involving the rabbit eye, where retinal lesions down to at least 1 mm can be detected. One difficulty involves scattering light emanating from the relatively large optic disc and the myelinated nerve fibers, which makes the use of a mfERG system, in which the fundus can be visualized during stimulation, mandatory.
Collapse
|
17
|
Chan HL, Chu HW, Ng YF, Tam WK, Young SM, Lam CH, Cheung AL. The detection of small relative simulated field defects using multifocal VEPs. Ophthalmic Physiol Opt 2005; 25:224-32. [PMID: 15854069 DOI: 10.1111/j.1475-1313.2005.00273.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
INTRODUCTION The multifocal visual-evoked potential (mfVEP) has been widely used in the study of diseases of the visual system. However, the sensitivity of the mfVEP in the objective detection of relative field defects has not been determined. This study investigates variations in mfVEP responses while simulating relative field defects by using different luminous transmission masks [neutral density (ND) filters] on the stimulus pattern. METHODS Simulated relative field defects with four different luminous transmissions were obtained by using 0.2, 0.4, 0.6, and 0.8 ND filters, 5 degrees in size, at two different retinal eccentricities (10 and 16 degrees) on a standard mfVEP dartboard stimulus. Eleven normal subjects were recruited for mfVEP measurements. The response amplitudes and latencies of the N1 and P1 of the mfVEP, with and without small simulated relative field defects, were compared. RESULTS The mfVEP amplitudes of N1 and P1 decreased substantially when 0.6 and 0.8 ND filters were introduced. The effects were similar at both the 10- and 16-degree eccentricities but there was no change in latency with simulated field defects at either location. CONCLUSIONS The mfVEP can detect a simulated relative field defect 5 degrees in size starting with 0.6 log unit reduction in luminance at both 10-degree and 16-degree eccentricities. This illustrates that the sensitivity of the mfVEP measurement is nearly comparable with that of the Humphrey Visual Field Analyser.
Collapse
Affiliation(s)
- H L Chan
- Department of Optometry and Radiography, The Hong Kong Polytechnic University, China.
| | | | | | | | | | | | | |
Collapse
|
18
|
Abstract
AIM To study the effect of aging retina on the multifocal electroretinogram (mfERG). METHODS A total of 18 young subjects (age 18-24 years) and 36 elderly subjects (aged 60-85 years) with intraocular lenses (IOLs) were recruited for this study. No subjects had significant eye diseases or media opacities. mfERG was measured in standard conditions using the VERIS system (version 4.1). There were three groups of 18 subjects: (1) 18-25 years, (2) 60-70 years, and (3) 75-85 years. mfERG responses were grouped into central, paracentral, and peripheral regions for analysis. The N1 amplitude, P1 amplitude, N1 latency, and P1 latency of the first-order responses were analysed. RESULTS Age had no effect on P1 latency, N1 amplitude, and P1 amplitude; however, N1 latencies from central to peripheral regions were significantly longer for group 3 than for group 1. CONCLUSIONS This study suggests that measured age-related decreases in mfERG responses are due to optical factors (decrease in retinal light levels, scatter) before the age of 70 years, but neural factors significantly affect mfERG topography after the age of 70 years.
Collapse
Affiliation(s)
- W-K Tam
- Department of Optometry and Radiography, The Hong Kong Polytechnic University, Hong Kong
| | | | | | | | | | | |
Collapse
|