Electrophysiology and ocular blood flow in a family with dominant optic nerve atrophy and a mutation in the OPA1 gene

Chan

Survey of Ophthalmology

et al. 2007

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 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.

Section: Other Multifocal Techniquesmentioning

confidence: 98%

The Clinical Applications of Multifocal Electroretinography: A Systematic Review

Chan

Survey of Ophthalmology

et al. 2007

Invest. Ophthalmol. Vis. Sci.

“…9,31 In addition, the electroretinograms in patients with ADOA are, in general, normal. 1,[41][42][43] Thus, the photoreceptor layer is most likely not affected in this disease. The overall sensory retinal thickness at the fovea was normal in patients with ADOA probably because the RNFL and ganglion cell layer are essentially absent in this area.…”

Section: Discussionmentioning

confidence: 99%

Reduction of Inner Retinal Thickness in Patients with Autosomal Dominant Optic Atrophy Associated withOPA1Mutations

Ito¹,

Nakamura²,

Yamakoshi³

et al. 2007

PURPOSE.To determine the morphologic changes in the retina in the macula and around the optic disc in patients with autosomal dominant optic atrophy (ADOA) associated with a mutation in the OPA1 gene. METHODS. Cross-sectional images of the macular area of the retina were obtained by optical coherence tomography (OCT) in patients with ADOA who had a heterozygous mutation in the OPA1 gene. There were 15 eyes of eight patients from five families: four men and four women. The average age of the patients was 48.1 years. In the OCT images, the cross sections of the sensory retina were divided manually into four areas. The thickness of the overall sensory retina and the divided areas were measured at 1 and 2 mm on the temporal, nasal, superior, and inferior sides of the fovea as well as at the fovea. The thickness of the retinal nerve fiber layer (RNFL) around the optic discs was measured by taking circular scans (3.4 mm in diameter) centered on the optic disc. The results in the patients with ADOA were compared with those from 11 normal control subjects. RESULTS. The overall thickness of the sensory retina in the macular area was significantly thinner in the patients with ADOA than in the control subjects at all points except the fovea (P Ͻ 0.0001). The RNFL in the macular area in the patients with ADOA was significantly thinner than that in control subjects at all points (P Ͻ 0.0001), especially at 1 mm from the fovea. The circumpapillary RNFL was significantly thinner at the temporal, superior, and inferior areas in patients with ADOA but not in the nasal area. The total cross-sectional area of the circumpapillary RNFL was significantly correlated with visual acuity. The thickness of the combined ganglion cell layer, inner plexiform layer, inner nuclear layer, and outer plexiform layer in the macular area was significantly thinner in the patients (P Ͻ 0.0056). The thickness of the outer nuclear layer and the photoreceptor inner segments and the thickness of the photoreceptor outer segments were not significantly different between the patients with ADOA and normal control subjects. CONCLUSIONS. The RNFL and the layer including the ganglion cell layer are significantly thinner in patients with ADOA associated with an OPA1 gene mutation, whereas the photoreceptor layers are not affected morphologically. The inner retina is the main area of the retina altered in ADOA. (Invest Ophthalmol Vis Sci. 2007;48:4079 -4086)

Acta Ophthalmologica Scandinavica

“…The amplitudes in a defined central region of the cortical response, where we usually obtain the best results ( Fig. 1) (Gra¨nse et al 2003), were measured and compared with those in 10 normal controls ( (Berson 1993). Electrophysiological findings in RP patients were reported as early as 1951 (Bjo¨rk & Karpe 1951), demonstrating that the electroretinograms were often extinguished.…”

Section: Multifocal Vepmentioning

confidence: 99%

Full‐field ERG, multifocal ERG and multifocal VEP in patients with retinitis pigmentosa and residual central visual fields

Gränse¹,

Ponjavic²,

Andréasson³

2004

Self Cite

ABSTRACT.Purpose: To evaluate (with three different electrophysiological methods) the residual retinal function in a selected group of patients with retinitis pigmentosa and remaining small central visual fields. Methods: Fourteen patients from several different genetic subgroups, who had been followed with visual acuity and visual field testing for periods up to 32 years, were examined. Ophthalmological examination included full-field electroretinography (ERG), multifocal electroretinography (mfERG) and multifocal visual evoked potential (mfVEP). Results: The ERGs were severely reduced in all patients. The mfERGs demonstrated the residual central retinal function in five of the patients. The mfVEPs showed measurable amplitudes centrally in most of the patients. The follow-up examinations demonstrated the slowly progressive course of the disease with preservation or only slight further loss of visual fields over a period of 7-32 years. Conclusion: Patients with retinitis pigmentosa may not always follow the typical natural course with progressive loss of visual fields, which may in some patients remain unaffected over several decades. Multifocal ERG and mfVEP may be clinically useful for evaluating remaining visual function in these patients.