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Jean Denis Degos - One of the best experts on this subject based on the ideXlab platform.
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Selective deficit ofvisual size perception: two cases ofhemiMicropsia
1994Co-Authors: L. Cohen, C Meyrignac, Stanislas Dehaene, Jean Denis DegosAbstract:HemiMicropsia isa raredisorder of visualperception characterised by an apparent reduction ofthesizeofobjects whenpresented inonehemifield. We reporttwo casesof hemuMicropsia resulting fromfocal brainlesions. The first patient wasanartteacher andcould accurately depicthisabnormalvisual perception. Hesubsequently diedandhis brainwasexamined postmortem.Inthe secondpatient, Micropsia wasassessed by a quantified sizecomparison task. The sizeofa givenobject isnormally perceived asconstant acrossanyspatial position. HemiMicropsia may thusbe considered alimited violation ofthesize constancyprinciple. Behavioural and anatomical dataarediscussed inrelation totheneural basisofvisual object per- ception inhumans. (7Neurol Neurosurg Psychiatry 1994;57:73-78)
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Selective deficit of visual size perception: Two cases of hemiMicropsia
Journal of Neurology Neurosurgery and Psychiatry, 1994Co-Authors: L. Cohen, F. Gray, Stanislas Dehaene, C Meyrignac, Jean Denis DegosAbstract:HemiMicropsia is a rare disorder of visual perception characterized by an apparent reduction of the size of objects when presented in one hemifield. We report two cases of hemiMicropsia resulting from focal brain lesions. The first patient was an art teacher and could accurately depict his abnormal visual perception. He subsequently died and his brain was examined post mortem. In the second patient, Micropsia was assessed by a quantified size comparison task. The size of a given object is normally perceived as constant across any spatial position. HemiMicropsia may thus be considered a limited violation of the size constancy principle. Behavioural and anatomical data are discussed in relation to the neural basis of visual object perception in humans.
Tetsuro Oshika - One of the best experts on this subject based on the ideXlab platform.
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Changes in aniseikonia and influencing-factors following successful macula-off retinal detachment surgery.
Scientific Reports, 2019Co-Authors: Tomoya Murakami, Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:This study investigated the changes in the severity of aniseikonia after surgery for macula-off retinal detachment (RD), and the relationship between aniseikonia and retinal microstructures. The study included 26 eyes of 26 patients undergoing RD surgery. Visual acuity was measured preoperatively, and at 3, 6, and 12 months postoperatively. Degree of aniseikonia and OCT images were obtained at 3, 6, and 12 months postoperatively. The aniseikonia values (mean ± standard deviation) at 3, 6, and 12 months postoperatively were −5.3 ± 4.2%, −4.4 ± 4.4%, and −3.1 ± 3.2%, respectively. Significant improvement was observed from 3 to 12 months postoperatively (P = 0.001). Twelve months postoperatively, 14 eyes had Micropsia, 1 eye had macropsia, and 11 eyes were free of aniseikonia. Stepwise multiple regression analyses revealed that the severity of aniseikonia at 12 months postoperatively was significantly associated with postoperative development of cystoid macular edema (CME) and epiretinal membrane (ERM), as well as area of preoperative RD. In conclusion, although aniseikonia was gradually relieved after RD surgery during a 1-year follow-up period, approximately half of patients had aniseikonia and almost all of them had Micropsia. Aniseikonia was associated with presence of postoperative CME, ERM, and area of preoperative RD.
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Aniseikonia in various retinal disorders
Graefe's Archive for Clinical and Experimental Ophthalmology, 2017Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:Purpose The purpose was to quantify and compare the severity of aniseikonia in patients undergoing vitrectomy for various retinal disorders. Methods We studied 357 patients with retinal disorders including epiretinal membrane (ERM), macular hole (MH), cystoid macular edema with branch / central retinal vein occlusion (BRVO-CME / CRVO-CME), diabetic macular edema (DME), macula-off rhegmatogenous retinal detachment (M-off RD), and macula-on RD (M-on RD) as well as 31 normal controls. The amount of aniseikonia was measured using the New Aniseikonia Test preoperatively and at 6 months postoperatively. Results Of all patients, 59% presented aniseikonia. Preoperative and postoperative mean aniseikonia were 4.0 ± 4.1% and 3.0 ± 3.6%, respectively. In particular, 68% of patients with ERM had macropsia, and approximately half of MH, RVO-CME, DME, and M-off RD patients had Micropsia. Preoperative aniseikonia was significantly severe in ERM than in other disorders. Vitrectomy improved aniseikonia only in MH, while visual acuity was improved in all disorders except CRVO-CME. Conclusion More than half of the patients showed aniseikonia preoperatively. A majority of ERM patients exhibited macropsia, whereas MH, RVO-CME, DME, and macula-off RD patients presented Micropsia. The aniseikonia score was greatest in ERM patients. In most retinal disorders, surgery significantly improved visual acuity, but not aniseikonia.
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Aniseikonia and Foveal Microstructure in Patients with Idiopathic Macular Hole
Ophthalmology, 2016Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Yuki Moriya, Tomoya Murakami, Tetsuro OshikaAbstract:Purpose To quantify the severity of aniseikonia in patients undergoing vitrectomy for idiopathic macular hole (MH) and to examine any relationship between aniseikonia and the foveal microstructure. Design Prospective, consecutive, interventional case series. Participants We included 56 eyes of 56 patients who underwent vitrectomy to treat idiopathic MH. Methods We examined visual acuity, aniseikonia using the New Aniseikonia Test, and foveal structure using optical coherence tomography (OCT) before and 3, 6, and 12 months after surgery. Based on OCT images, minimum and base diameters of MH, height of MH, and defect lengths of the external limiting membrane (ELM), ellipsoid zone, and interdigitation zone were assessed. Main Outcome Measures Degree of aniseikonia before and after surgery. Results The mean aniseikonia was −3.2±4.6%, ranging from −15.5% to +5.0%. Of the patients, 55% had Micropsia, 7% had macropsia, and 38% had no aniseikonia. The mean absolute value of aniseikonia improved significantly from 3.8±4.1% before surgery to 1.0±1.5% at 12 months after surgery ( P P P P P Conclusions Approximately half of MH patients had Micropsia. Vitrectomy for MH improved aniseikonia. Preoperative aniseikonia was associated with MH size and the defect length of ELM.
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Aniseikonia and Foveal Microstructure after Retinal Detachment Surgery.
Investigative Ophthalmology & Visual Science, 2014Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:PURPOSE. To quantify aniseikonia after successful surgical repair of rhegmatogenous retinal detachment (RD), and to investigate the relationship between the severity of postoperative aniseikonia and retinal microstructures as well as clinical parameters. METHODS. The study included 106 eyes of 106 patients, without any history of ocular disease/ surgery and with less than 2 diopters of anisometropia, who had undergone successful retinal reattachment surgery. Aniseikonia was measured with the New Aniseikonia Test, and foveal microstructure was assessed with spectral-domain optical coherence tomography (OCT) at 6 months postoperatively. RESULTS. Twenty-eight of 106 patients (26%) had Micropsia; 17 patients (16%) had macropsia; and 61 patients (58%) had no aniseikonia. The mean absolute value of aniseikonia was 2.3 6 2.9% (range, � 12.5% to þ12.0%). Of 57 eyes with macula-on RD, 3 had Micropsia and 12 had macropsia. Of 49 eyes with macula-off RD, 25 had Micropsia and 5 had macropsia. Eyes with Micropsia mostly exhibited persistent or transient cystoid macular edema, subretinal fluid, hyperreflective or disruption of IS/OS line, while most of the eyes with macropsia presented epiretinal membrane. Stepwise multiple regression analysis revealed that postoperative bestcorrected visual acuity and the area of RD were significantly relevant to the mean absolute value of aniseikonia. CONCLUSIONS. These results suggested that approximately half of patients with successful repair of RD had aniseikonia. Eyes with macula-off RD tended to show Micropsia, while those with macula-on RD mostly presented macropsia. Micropsia and macropsia were primarily caused by respective specific abnormal structures at the foveal region.
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Time Course of Changes in Aniseikonia and Foveal Microstructure after Vitrectomy for Epiretinal Membrane
Ophthalmology, 2014Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:Purpose To quantify aniseikonia in patients undergoing vitrectomy for epiretinal membrane (ERM) and to investigate the relationship between the aniseikonia and the foveal microstructure by spectral-domain (SD) optical coherence tomography (OCT). Design Prospective, consecutive, interventional case series. Subjects This study included 44 eyes of 44 patients undergoing vitrectomy for idiopathic ERM. Methods We examined visual acuity and aniseikonia using the New Aniseikonia Test and SD-OCT before and 3 and 6 months after surgery. On the basis of the obtained OCT image, we divided the 1.0×1.0-mm area centered on the fovea into 9 sections at 0.25-mm intervals and quantified the following parameters using an image-processing program: central foveal thickness and mean thickness of the ganglion cell layer, inner nuclear layer (INL), and outer retinal layer (outer nuclear layer + outer plexiform layer). The status of the photoreceptor inner segment/outer segment junction, external limiting membrane, and cone outer segment tips also was evaluated. Main Outcome Measures Amount of aniseikonia 6 months after surgery. Results Of 44 patients, 39 (89%) had macropsia, 1 (2%) had Micropsia, and 4 (9%) had no aniseikonia preoperatively. Mean preoperative aniseikonia was 6.2%±4.5%. Vitrectomy significantly improved visual acuity in patients with ERM but did not change the amount of aniseikonia. Multiple regression analysis revealed that preoperative aniseikonia at 6 months was significantly related to preoperative INL thickness, whereas postoperative aniseikonia at 6 months was associated with postoperative INL thickness at 6 months. Preoperative INL thickness was found to be of significant prognostic value for postoperative aniseikonia at 6 months. Conclusions Most of the patients with ERM had macropsia. Aniseikonia was not reduced after surgery. The amount of aniseikonia was associated with INL thickness.
L. Cohen - One of the best experts on this subject based on the ideXlab platform.
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Selective deficit ofvisual size perception: two cases ofhemiMicropsia
1994Co-Authors: L. Cohen, C Meyrignac, Stanislas Dehaene, Jean Denis DegosAbstract:HemiMicropsia isa raredisorder of visualperception characterised by an apparent reduction ofthesizeofobjects whenpresented inonehemifield. We reporttwo casesof hemuMicropsia resulting fromfocal brainlesions. The first patient wasanartteacher andcould accurately depicthisabnormalvisual perception. Hesubsequently diedandhis brainwasexamined postmortem.Inthe secondpatient, Micropsia wasassessed by a quantified sizecomparison task. The sizeofa givenobject isnormally perceived asconstant acrossanyspatial position. HemiMicropsia may thusbe considered alimited violation ofthesize constancyprinciple. Behavioural and anatomical dataarediscussed inrelation totheneural basisofvisual object per- ception inhumans. (7Neurol Neurosurg Psychiatry 1994;57:73-78)
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Selective deficit of visual size perception: Two cases of hemiMicropsia
Journal of Neurology Neurosurgery and Psychiatry, 1994Co-Authors: L. Cohen, F. Gray, Stanislas Dehaene, C Meyrignac, Jean Denis DegosAbstract:HemiMicropsia is a rare disorder of visual perception characterized by an apparent reduction of the size of objects when presented in one hemifield. We report two cases of hemiMicropsia resulting from focal brain lesions. The first patient was an art teacher and could accurately depict his abnormal visual perception. He subsequently died and his brain was examined post mortem. In the second patient, Micropsia was assessed by a quantified size comparison task. The size of a given object is normally perceived as constant across any spatial position. HemiMicropsia may thus be considered a limited violation of the size constancy principle. Behavioural and anatomical data are discussed in relation to the neural basis of visual object perception in humans.
Tom H Williamson - One of the best experts on this subject based on the ideXlab platform.
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horizontal and vertical Micropsia following macula off rhegmatogenous retinal detachment surgical repair
Graefes Archive for Clinical and Experimental Ophthalmology, 2006Co-Authors: Marta Ugarte, Tom H WilliamsonAbstract:BACKGROUND: Dysmetropsia or distorted image size perception (smaller: Micropsia; larger: macropsia) is known to occur after successful surgical re-attachment for macula-off rhegmatogenous retinal detachment. However, the vertical and horizontal components of size distortion have not been previously quantified separately. The purpose of this article is to describe horizontal and vertical dysmetropsia occurring in patients following pars plana vitrectomy and gas treatment (octafluoropropane, C(3)F(8) or sulfur hexafluoride, SF(6)) for macula-off rhegmatogenous retinal detachment. MATERIAL AND METHODS: Four patients (mean+/-SD, 59+/-8 years; three women and one man) who had had pars plana vitrectomy and gas treatment for macula-off rhegmatogenous retinal detachment 6-7 months earlier underwent ocular examination, best corrected visual acuity test, threshold horizontal and vertical dysmetropsia measurement using a computerised version of the New Aniseikonia Test, slit-lamp examination and optical coherence tomography of the macula. RESULTS: All patients had binocular visual complaints including difficulty judging distances or reading, rivalry or asthenopia. The logMAR visual acuity (mean+/-SD) in the operated eye was 0.52+/-0.199 and 0.02+/-0.171 in the unaffected eye. All patients perceived the image as smaller (Micropsia) with the affected eye, with differences ranging from -9 to 0%. Four patients showed 3% or more size difference between horizontal and vertical meridians. CONCLUSIONS: Dysmetropsia does occur in symptomatic patients following successful surgical repair of macula-off rhegmatogenous retinal detachment by pars plana vitrectomy and gas treatment. The effect on image size is heterogenous across the retinal area affected.
Fumiki Okamoto - One of the best experts on this subject based on the ideXlab platform.
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Changes in aniseikonia and influencing-factors following successful macula-off retinal detachment surgery.
Scientific Reports, 2019Co-Authors: Tomoya Murakami, Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:This study investigated the changes in the severity of aniseikonia after surgery for macula-off retinal detachment (RD), and the relationship between aniseikonia and retinal microstructures. The study included 26 eyes of 26 patients undergoing RD surgery. Visual acuity was measured preoperatively, and at 3, 6, and 12 months postoperatively. Degree of aniseikonia and OCT images were obtained at 3, 6, and 12 months postoperatively. The aniseikonia values (mean ± standard deviation) at 3, 6, and 12 months postoperatively were −5.3 ± 4.2%, −4.4 ± 4.4%, and −3.1 ± 3.2%, respectively. Significant improvement was observed from 3 to 12 months postoperatively (P = 0.001). Twelve months postoperatively, 14 eyes had Micropsia, 1 eye had macropsia, and 11 eyes were free of aniseikonia. Stepwise multiple regression analyses revealed that the severity of aniseikonia at 12 months postoperatively was significantly associated with postoperative development of cystoid macular edema (CME) and epiretinal membrane (ERM), as well as area of preoperative RD. In conclusion, although aniseikonia was gradually relieved after RD surgery during a 1-year follow-up period, approximately half of patients had aniseikonia and almost all of them had Micropsia. Aniseikonia was associated with presence of postoperative CME, ERM, and area of preoperative RD.
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Aniseikonia in various retinal disorders
Graefe's Archive for Clinical and Experimental Ophthalmology, 2017Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:Purpose The purpose was to quantify and compare the severity of aniseikonia in patients undergoing vitrectomy for various retinal disorders. Methods We studied 357 patients with retinal disorders including epiretinal membrane (ERM), macular hole (MH), cystoid macular edema with branch / central retinal vein occlusion (BRVO-CME / CRVO-CME), diabetic macular edema (DME), macula-off rhegmatogenous retinal detachment (M-off RD), and macula-on RD (M-on RD) as well as 31 normal controls. The amount of aniseikonia was measured using the New Aniseikonia Test preoperatively and at 6 months postoperatively. Results Of all patients, 59% presented aniseikonia. Preoperative and postoperative mean aniseikonia were 4.0 ± 4.1% and 3.0 ± 3.6%, respectively. In particular, 68% of patients with ERM had macropsia, and approximately half of MH, RVO-CME, DME, and M-off RD patients had Micropsia. Preoperative aniseikonia was significantly severe in ERM than in other disorders. Vitrectomy improved aniseikonia only in MH, while visual acuity was improved in all disorders except CRVO-CME. Conclusion More than half of the patients showed aniseikonia preoperatively. A majority of ERM patients exhibited macropsia, whereas MH, RVO-CME, DME, and macula-off RD patients presented Micropsia. The aniseikonia score was greatest in ERM patients. In most retinal disorders, surgery significantly improved visual acuity, but not aniseikonia.
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Aniseikonia and Foveal Microstructure in Patients with Idiopathic Macular Hole
Ophthalmology, 2016Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Yuki Moriya, Tomoya Murakami, Tetsuro OshikaAbstract:Purpose To quantify the severity of aniseikonia in patients undergoing vitrectomy for idiopathic macular hole (MH) and to examine any relationship between aniseikonia and the foveal microstructure. Design Prospective, consecutive, interventional case series. Participants We included 56 eyes of 56 patients who underwent vitrectomy to treat idiopathic MH. Methods We examined visual acuity, aniseikonia using the New Aniseikonia Test, and foveal structure using optical coherence tomography (OCT) before and 3, 6, and 12 months after surgery. Based on OCT images, minimum and base diameters of MH, height of MH, and defect lengths of the external limiting membrane (ELM), ellipsoid zone, and interdigitation zone were assessed. Main Outcome Measures Degree of aniseikonia before and after surgery. Results The mean aniseikonia was −3.2±4.6%, ranging from −15.5% to +5.0%. Of the patients, 55% had Micropsia, 7% had macropsia, and 38% had no aniseikonia. The mean absolute value of aniseikonia improved significantly from 3.8±4.1% before surgery to 1.0±1.5% at 12 months after surgery ( P P P P P Conclusions Approximately half of MH patients had Micropsia. Vitrectomy for MH improved aniseikonia. Preoperative aniseikonia was associated with MH size and the defect length of ELM.
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Aniseikonia and Foveal Microstructure after Retinal Detachment Surgery.
Investigative Ophthalmology & Visual Science, 2014Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:PURPOSE. To quantify aniseikonia after successful surgical repair of rhegmatogenous retinal detachment (RD), and to investigate the relationship between the severity of postoperative aniseikonia and retinal microstructures as well as clinical parameters. METHODS. The study included 106 eyes of 106 patients, without any history of ocular disease/ surgery and with less than 2 diopters of anisometropia, who had undergone successful retinal reattachment surgery. Aniseikonia was measured with the New Aniseikonia Test, and foveal microstructure was assessed with spectral-domain optical coherence tomography (OCT) at 6 months postoperatively. RESULTS. Twenty-eight of 106 patients (26%) had Micropsia; 17 patients (16%) had macropsia; and 61 patients (58%) had no aniseikonia. The mean absolute value of aniseikonia was 2.3 6 2.9% (range, � 12.5% to þ12.0%). Of 57 eyes with macula-on RD, 3 had Micropsia and 12 had macropsia. Of 49 eyes with macula-off RD, 25 had Micropsia and 5 had macropsia. Eyes with Micropsia mostly exhibited persistent or transient cystoid macular edema, subretinal fluid, hyperreflective or disruption of IS/OS line, while most of the eyes with macropsia presented epiretinal membrane. Stepwise multiple regression analysis revealed that postoperative bestcorrected visual acuity and the area of RD were significantly relevant to the mean absolute value of aniseikonia. CONCLUSIONS. These results suggested that approximately half of patients with successful repair of RD had aniseikonia. Eyes with macula-off RD tended to show Micropsia, while those with macula-on RD mostly presented macropsia. Micropsia and macropsia were primarily caused by respective specific abnormal structures at the foveal region.
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Time Course of Changes in Aniseikonia and Foveal Microstructure after Vitrectomy for Epiretinal Membrane
Ophthalmology, 2014Co-Authors: Fumiki Okamoto, Yoshimi Sugiura, Yoshifumi Okamoto, Takahiro Hiraoka, Tetsuro OshikaAbstract:Purpose To quantify aniseikonia in patients undergoing vitrectomy for epiretinal membrane (ERM) and to investigate the relationship between the aniseikonia and the foveal microstructure by spectral-domain (SD) optical coherence tomography (OCT). Design Prospective, consecutive, interventional case series. Subjects This study included 44 eyes of 44 patients undergoing vitrectomy for idiopathic ERM. Methods We examined visual acuity and aniseikonia using the New Aniseikonia Test and SD-OCT before and 3 and 6 months after surgery. On the basis of the obtained OCT image, we divided the 1.0×1.0-mm area centered on the fovea into 9 sections at 0.25-mm intervals and quantified the following parameters using an image-processing program: central foveal thickness and mean thickness of the ganglion cell layer, inner nuclear layer (INL), and outer retinal layer (outer nuclear layer + outer plexiform layer). The status of the photoreceptor inner segment/outer segment junction, external limiting membrane, and cone outer segment tips also was evaluated. Main Outcome Measures Amount of aniseikonia 6 months after surgery. Results Of 44 patients, 39 (89%) had macropsia, 1 (2%) had Micropsia, and 4 (9%) had no aniseikonia preoperatively. Mean preoperative aniseikonia was 6.2%±4.5%. Vitrectomy significantly improved visual acuity in patients with ERM but did not change the amount of aniseikonia. Multiple regression analysis revealed that preoperative aniseikonia at 6 months was significantly related to preoperative INL thickness, whereas postoperative aniseikonia at 6 months was associated with postoperative INL thickness at 6 months. Preoperative INL thickness was found to be of significant prognostic value for postoperative aniseikonia at 6 months. Conclusions Most of the patients with ERM had macropsia. Aniseikonia was not reduced after surgery. The amount of aniseikonia was associated with INL thickness.