Kunifusa Tamada

Sensitivity and Specificity of Photopic Negative Response of Focal Electoretinogram to Detect Glaucomatous Eyes

Aims To determine the sensitivity and specificity of the photopic negative response (PhNR) of the focal electroretinograms (ERG; focal PhNR) to detect glaucomatous eyes with different degrees of visual field defects. Methods One-hundred and fourteen eyes of 114 patients with open angle glaucoma and 42 eyes of 42 normal controls were studied. The focal ERGs were elicited by a 15° stimulus spot centred on the macula, and on the supero-temporal and on the infero-temporal areas of the macula. The receiver operating characteristic curves were determined to obtain optimal cut-off values. Eyes were classified as being glaucomatous when their focal PhNRs were less than the cut-off values in either retinal area (combined criterion). Results The focal PhNR amplitudes were significantly reduced with an advance in the stage of glaucoma. In early glaucoma, the sensitivities of the PhNR measured for each retinal area ranged from 58.1% to 80.7%. The sensitivities were significantly increased to 90.6% and 96.9% for the focal PhNR amplitude and the focal PhNR/b-wave amplitude ratio, respectively, when the combined criterion was employed. The specificity was >90%. Conclusions Focal PhNRs have diagnostic ability in detecting early glaucoma with high sensitivity and specificity, especially when the combined criterion is used.

Comparison of Photopic Negative Response of Full-Field and Focal Electroretinograms in Detecting Glaucomatous Eyes

Purpose. To compare the photopic negative response (PhNR) of the full-field electroretinogram (ERG) to the PhNR of the focal ERGs in detecting glaucoma. Methods. One hundred and three eyes with glaucoma and 42 normal eyes were studied. Full-field ERGs were elicited by red stimuli on a blue background. The focal ERGs were elicited by a 15° white stimulus spot centered on the macula, the superotemporal or the inferotemporal areas of the macula. Results. In early glaucoma, the areas under the receiver operating characteristic curves (AUCs) were significantly larger for the focal PhNR (0.863–0.924) than those for the full-field PhNR (0.666–0.748) (P < .05). The sensitivity was significantly higher for the focal PhNR than for the full-field PhNR in early (P < .01) and intermediate glaucoma (P < .05). In advanced glaucoma, there was no difference in the AUCs and sensitivities between the focal and full-field PhNRs. Conclusions. The focal ERG has the diagnostic ability with higher sensitivity in detecting early and intermediate glaucoma than the full-field ERG.

Correlation between photopic negative response of focal electroretinograms and local loss of retinal neurons in glaucoma.

Purpose: To determine the relationship between the photopic negative response of the focal electroretinogram and the structural parameters of the inner retina and optic nerve head in glaucoma. Methods: Sixty-one eyes of 61 patients with open angle glaucoma, 13 eyes of 13 patients who were classified as glaucoma suspects, and 30 eyes of 30 normal subjects were studied. The focal electroretinograms were elicited by a 15° circular white stimulus on a white background centered on the fovea. The focal electroretinograms were also elicited by half of an annulus placed above or below the macula. The diameter of the inner border of the annulus was 15° and that of the outer border was 30°. The structure of the optic nerve head and retinal nerve fiber layer thickness were evaluated by scanning laser ophthalmoscopy and laser scanning polarimetry, respectively. Results: The amplitudes of the focal photopic negative responses and the ratio of the focal photopic negative response/b-wave amplitude were linearly correlated with the corresponding retinal nerve fiber layer thickness in the superior/temporal and inferior/temporal regions (r = 0.43 to 0.47; P < 0.0001) but not in the temporal region. The focal photopic negative response amplitude and focal photopic negative response/b-wave amplitude ratio were also linearly and significantly correlated with the corresponding rim areas and cup/disc area ratio (r = 0.38 to 0.50, P < 0.0001). Conclusions: These results strongly suggest that the anatomical losses of retinal neurons in local areas of the retina or optic nerve head are a cause of the reduction in the amplitude of the focal photopic negative response in open angle glaucoma.

Photopic negative response of full-field and focal macular electroretinograms in patients with optic nerve atrophy

PurposeTo determine alterations of the photopic negative response (PhNR) in the full-field and focal macular electroretinograms (ERGs) of patients with optic nerve atrophy (ONA).MethodsTen eyes of eight patients, five women and three men with a mean age of 55.1 years, with ONA were studied. Thirty-six age-matched controls were examined using the same protocol. Full-field cone ERGs were elicited by red stimuli on a blue background, and focal ERGs were elicited by a 15° white stimulus spot centered on the macular region.ResultsThe a- and b-wave amplitudes of the full-field and focal ERGs of the affected eyes were similar to those of the control eyes. The full-field PhNR amplitudes were significantly reduced in six of ten affected eyes. Four eyes with normal full-field PhNR amplitudes had central scotomas. The focal PhNR amplitudes were smaller than the normal limits in all affected eyes.ConclusionsThe reduction of the full-field and focal PhNR in eyes with ONA indicates that both originate from the retinal ganglion cells (RGCs) and their axons. The findings also indicate that focal PhNR amplitudes can be used to assess focal damages of both the RGCs and their axons in eyes with ONA.

Lovastatin Alters TGF-β-Induced Epithelial-Mesenchymal Transition in Porcine Lens Epithelial Cells

Purpose: To determine whether lovastatin affects the epithelial-mesenchymal transition (EMT) in porcine lens epithelial cells (LECs) induced by transforming growth factor-β (TGF-β). Materials and Methods: Porcine LECs were cultured in Dulbecco’s Modified Eagle Medium (DMEM) for 24 h. The cultured cells were then exposed or not exposed to lovastatin (10 µM) for 18 h and then stimulated with or not stimulated with TGF-β2 (5 ng/ml) for 24 h. The expression of α-smooth muscle actin (α-SMA), a marker of myofibroblasts, was determined by real-time PCR, and the expression of α-SMA protein was determined by Western blot. The effect of lovastatin on the expression of the mRNA of collagen type 1 (COL1) was determined by real-time PCR. To assess cell contractility, LECs were cultured in collagen gel with or without pretreatment of lovastatin and exposure of TGF-β2. The longest and shortest diameters of the gels were measured and the area was determined. Results: Exposure of LECs to TGF-β2 increased the expression of the mRNA and protein of α-SMA and the mRNA of COL1A1. TGF-β2 increased the degree of contraction of collagen gel. These findings indicated that TGF-β2 promoted EMT, and the pretreatment of the LECs with lovastatin blocked these changes induced by TGF-β2. Conclusion: Lovastatin inhibits the TGF-β-induced EMT of cultured porcine LECs. This suggests that lovastatin should be considered as a new agent to prevent postoperative complications associated with EMT of LECs.

Predominant loss of rod-mediated electroretinogram response in a case of acute annular outer retinopathy

described as “bilateral idiopathic multifocal retinal pigment epithelial detachments in otherwise healthy middle-aged adults,” as described by Gass and associates. The chief complaint of two patients was a mild blurring of vision, and that of two other patients was a blind area in the central visual fi eld, but four cases patients were asymptomatic. The size of the RPEDs ranged from one-sixteenth to one-half disc diameter (DD). A large RPED of more than 1 DD was observed in the central area of one American patient. Three patients were studied by IA, and they showed latephase hyperfl uorescence. Three patients were also examined by OCT, and the OCT images showed hyporefl ective spaces posterior to a smooth, elevated retinal pigment epithelium (RPE). Two cases were complicated by a CNV and extensive bleeding beneath the RPE and retina that resulted in a visual acuity decrease. Most of the eyes had a relatively good prognosis except for one eye of those reported by Gass and associates. The mfERG responses were slightly reduced in the central area of both eyes in our patient. The RPE in the macular area may be predominantly affected in this disease. Reduced mfERG responses in the central area may indicate secondary degeneration of the sensory retina in the macular area.

Differences in Functional Loss Associated with Ganglion Cell Complex Thinning between Patients with Glaucoma and Postoperative Macular Hole

Abstract Purpose: To compare the changes in the photopic negative response (PhNR) of the focal macular electoretinogram (fmERG) caused by a thinning of the ganglion cell complex (GCC) between patients with open angle glaucoma (OAG) and after successful macular hole (MH) surgery. Methods: Twenty-seven eyes of 27 OAG patients (OAG group), 28 eyes of 28 MH patients (MH group) and 23 eyes of 23 normal volunteers (control group) were studied. The OAG patients had early stage of glaucoma. The MH patients had been successfully treated with vitrectomy 12 months earlier. The averaged GCC thickness in the macular area (15 degree in a diameter) was measured by SD-OCT. The fmERGs were elicited by a 15° stimulus centered on the fovea. Results: The GCC was significantly thinner in the OAG and MH groups than in the control group (p < 0.0001). The PhNR amplitude and PhNR/b-wave amplitude ratio were significantly reduced in the OAG group compared to the control (p < 0.0001), while no significant reduction of the PhNR amplitude was observed in the MH group. The PhNR amplitude and PhNR/b-wave amplitude ratio were significantly correlated with the GCC thickness in the OAG group (R2 = 0.741 for the PhNR amplitude, R2 = 0.564 for the PhNR/b-wave amplitude ratio, p < 0.0001 for both). There were significant differences in the slopes of regression lines plotting the GCC thickness and the PhNR amplitude (p < 0.05) or the PhNR/b-wave amplitude ratio (p < 0.0005) between the OAG and MH groups. Conclusions: The thinning of the GCC affects the RGC function in the macula area differently for patients with OAG and patients after MH closure.

Depolarizing focal macular electroretinogram pattern after photodynamic therapy in a patient with polypoidal choroidal vasculopathy

tissue with a shallow subretinal space (Fig. 1B). The vitrectomy was canceled, and his right BCVA improved to 0.6 after another month. Eighteen months after the initial visit, the patient noticed decreased vision in his left eye. BCVA was 0.7 OD and 0.4 OS. OCT in his left eye showed a full-thickness macular hole with perifoveal cysts and a separated posterior hyaloid membrane containing a pseudo-operculum (Fig. 2A). The right macula was normal. While waiting for vitrectomy, the patient returned for a two-month follow-up visit, during which we discovered the spontaneous closure of the macular hole in his left eye, with a similar OCT image as that observed in his right eye (Fig. 2B), although BCVA remained 0.4. Six months later, the left fovea recovered its normal confi guration, except for a split in the photoreceptor junction line between the inner and outer segments (IS/OS line) (Fig. 2C). At the follow-up 37 months after the initial visit, despite cataract formation OU, BCVA was 0.8 OD and 0.9 OS. Spectral-domain OCT (Cirrus OCT; Carl Zeiss Meditec) confi rmed the integrity of the IS/OS line OU (Figs. 1D and 2D).