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Jun Akiba - One of the best experts on this subject based on the ideXlab platform.
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classification of Posterior Vitreous Detachment
Clinical Ophthalmology, 2013Co-Authors: Akihiro Kakehashi, Mikiko Takezawa, Jun AkibaAbstract:Diagnosing a Posterior Vitreous Detachment (PVD) is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography (OCT). By biomicroscopy, the Vitreous condition is determined based on the presence or absence of a PVD. The PVD then is classified as either a complete Posterior Vitreous Detachment (C-PVD) or a partial Posterior Vitreous Detachment (P-PVD). A C-PVD is further divided into a C-PVD with collapse and a C-PVD without collapse, while a P-PVD is divided into a P-PVD with shrinkage of the Posterior hyaloid membrane (P-PVD with shrinkage) and a P-PVD without shrinkage of the Posterior hyaloid membrane (P-PVD without shrinkage). A P-PVD without shrinkage has a subtype characterized by Vitreous gel attachment through the premacular hole in a Posterior hyaloid membrane to the macula (P-PVD without shrinkage [M]). By OCT, a shallow PVD is classified as the absence of a shallow PVD or as a shallow PVD. A shallow PVD is then subclassified as a shallow PVD without shrinkage of the Posterior Vitreous cortex, a shallow PVD with shrinkage of the Posterior Vitreous cortex, and a peripheral shallow PVD. A shallow PVD without shrinkage of the Posterior Vitreous cortex has two subtypes: an age-related shallow PVD and a perifoveal PVD associated with a macular hole.
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Posterior Vitreous Detachment induced by injection of plasmin and sulfur hexafluoride in the rabbit Vitreous
Retina-the Journal of Retinal and Vitreous Diseases, 1999Co-Authors: Taiichi Hikichi, Jun Akiba, Masanori Kado, Norihiko Yanagiya, Akitoshi YoshidaAbstract:PURPOSE To investigate whether an injection of plasmin and sulfur hexafluoride (SF6) can induce Posterior Vitreous Detachment (PVD) without vitrectomy. METHODS One eye each of 15 New Zealand white rabbits was assigned to one of three groups. Eyes in group 1 received a Vitreous injection of 1 unit of human plasmin (0.1 mL reconstituted in balanced salt solution) and 0.5 mL of SF6; eyes in group 2 received a Vitreous injection of plasmin alone; eyes in group 3 received a Vitreous injection of SF6 alone. Seven days after injection, all animals were monitored electroretinographically and killed, and the eyes were enucleated. After fixation, scanning electron microscopy was performed. RESULTS In group 1 eyes, the retinal surface was smooth except for the Vitreous base, which showed complete separation of the Vitreous cortex from the retina, indicating PVD. In group 2 and 3 eyes, sparse collagen fibers remained on the retinal surface. CONCLUSION Vitreous injection of plasmin combined with SF6 can induce PVD without vitrectomy.
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variations of Posterior Vitreous Detachment
British Journal of Ophthalmology, 1997Co-Authors: Akihiro Kakehashi, Jun Akiba, Masanori Kado, Hiroyuki HirokawaAbstract:AIMS—To identify variations in Posterior Vitreous Detachment (PVD) and establish a clinical classification system for PVD. METHODS—400 consecutive eyes were examined using biomicroscopy and Vitreous photography and classified the PVD variations—complete PVD with collapse, complete PVD without collapse, partial PVD with thickened Posterior Vitreous cortex (TPVC), or partial PVD without TPVC. RESULTS—In each PVD type, the most frequently seen ocular pathologies were as follows: in complete PVD with collapse (186 eyes), age related changes without vitreoretinal diseases (77 eyes, 41.4%) and high myopia (55 eyes, 29.6%); in complete PVD without collapse (39 eyes), uveitis (23 eyes, 59.0%) and central retinal vein occlusion (8 eyes, 20.5%); in partial PVD with TPVC (64 eyes), proliferative diabetic retinopathy (30 eyes, 46.9%); and in partial PVD without TPVC (111 eyes), age related changes without vitreoretinal diseases (62 eyes, 55.9%). This PVD categorisation was significantly associated with the prevalence of each vitreoretinal disease (p<0.0001, χ2 test on contingency table). CONCLUSIONS—PVD variations can be classified into four types, which is clinically useful because each type corresponds well to specific vitreoretinal changes.
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comparison of the prevalence of Posterior Vitreous Detachment in whites and japanese
Ophthalmic Surgery and Lasers, 1995Co-Authors: Taiichi Hikichi, Jun Akiba, Hiroyuki Hirokawa, Akihiro Kakehashi, Masanori Kado, Akitoshi Voshida, Clement L. TrempeAbstract:The Vitreous condition of healthy white (n = 551) and Japanese (n = 528) eyes were reviewed and compared with respect to the prevalence of Posterior Vitreous Detachment (PVD) in the two groups. No white or Japanese patient 39 years of age or younger had PVD; the prevalence among those older than 39 increased with age in the fifth through the ninth decades, i.e., respectively, to 4%, 24%, 37% 59%, and 87% in the whites, and to 5%, 21%, 43%, 72%, and 82% in the Japanese. In none of these decades was there any significant difference between the prevalence of complete or partial PVD in the whites and the Japanese. This finding is significant because the vitreoretinal relationship influences the development and prognoses of the various vitreoretinal disorders.
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Prevalence of Posterior Vitreous Detachment in high myopia.
Ophthalmology, 1993Co-Authors: Jun AkibaAbstract:Background: Posterior Vitreous Detachment is known to develop early in high myopia. However, the prevalence of Posterior Vitreous Detachment in relation to patient age and degree of myopia has not been studied by modern Vitreous examination methods. Methods: The Vitreous conditions of 224 eyes with high myopia (>-6 diopters [D]) were examined biomicroscopically with a +90-D preset lens and a Goldmann threemirror contact lens. The Vitreous conditions of 220 eyes with emmetropia (between −1 and +1 D) also were studied and served as controls. Results: In high myopia, no patients 29 years of age or younger had Posterior Vitreous Detachment. Thereafter, the prevalence of Posterior Vitreous Detachment increased with age (i.e., 23%, 29%, 44%, and 72% in the fourth through seventh decades, respectively, and 100% of patients 70 years or older). Moreover, Posterior Vitreous Detachment developed earlier in severe high myopia (>−10 D) than in moderate high myopia (>−6 to −10 D). In emmetropia, no patients 39 years of age or younger had Posterior Vitreous Detachment, and its prevalence also increased with age (i.e., 8%, 23%, 44%, 74%, and 86% in the fifth through ninth decades, respectively). Conclusion: In high myopia, Posterior Vitreous Detachment develops increasingly with age and degree of myopia. Although the sample size in each age group was small, the results suggested that Posterior Vitreous Detachment may develop nearly 10 years earlier in highly myopic than in emmetropic eyes.
Jose Lorenzo Carrero - One of the best experts on this subject based on the ideXlab platform.
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incomplete Posterior Vitreous Detachment prevalence and clinical relevance
Investigative Ophthalmology & Visual Science, 2012Co-Authors: Jose Lorenzo CarreroAbstract:w t d ● PURPOSE: To investigate the prevalence and clinical relevance of incomplete Posterior Vitreous Detachment (PVD). ● DESIGN: Prospective, observational cohort study. ● METHODS: SETTING: Institutional. PATIENTS: Consecutive patients without previous ocular history who were diagnosed with acute uncomplicated PVD. OBSERVATIONS: Baseline kinetic ultrasound evaluation differentiated Posterior Vitreous separation as complete or incomplete. Prospective follow-up searched for complications related to PVD. Multivariate analysis evaluated associations of baseline demographic and clinical characteristics to incomplete PVD. A Kaplan-Meier analysis evaluated the probability and its standard error of experiencing an adverse outcome. The log-rank test determined whether incomplete PVD modifies the natural history of PVD. MAIN OUTCOME MEASURES: Prevalence of incomplete PVD and the estimated incidence of late adverse outcomes such as new retinal tears, epimacular membranes, or both. ● RESULTS: A total of 54 of 207 patients had incomplete PVD (prevalence, 26.1%). Younger age and lattice degeneration were associated independently with incomplete PVD. After a mean follow-up of 5 years (range, 4 to 8 years), 16 patients (9.7%) experienced some adverse outcome. In 5 patients (2.7%), new retinal tears and 1 retinal Detachment developed. In 12 patients (7.6%), epimacular membranes developed. Patients with incomplete PVD at baseline experienced significantly more adverse outcomes than patients with complete PVD (Kaplan-Meier estimated probability and standard error, 19.2% and 0.061 vs 5.4% and 0.02; P .01, log-rank test). ● CONCLUSIONS: Up to one fourth of symptomatic, cute, and uncomplicated PVDs show incomplete posteior Vitreous separation. Delayed complications related to VD, like retinal tears and epimacular membranes, evelop more frequently in patients showing incomplete VD. (Am J Ophthalmol 2012;153:497–503. © 2012 y Elsevier Inc. All rights reserved.)
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incomplete Posterior Vitreous Detachment prevalence and clinical relevance
American Journal of Ophthalmology, 2012Co-Authors: Jose Lorenzo CarreroAbstract:Purpose To investigate the prevalence and clinical relevance of incomplete Posterior Vitreous Detachment (PVD). Design Prospective, observational cohort study. Methods setting: Institutional. patients: Consecutive patients without previous ocular history who were diagnosed with acute uncomplicated PVD. observations: Baseline kinetic ultrasound evaluation differentiated Posterior Vitreous separation as complete or incomplete. Prospective follow-up searched for complications related to PVD. Multivariate analysis evaluated associations of baseline demographic and clinical characteristics to incomplete PVD. A Kaplan-Meier analysis evaluated the probability and its standard error of experiencing an adverse outcome. The log-rank test determined whether incomplete PVD modifies the natural history of PVD. main outcome measures: Prevalence of incomplete PVD and the estimated incidence of late adverse outcomes such as new retinal tears, epimacular membranes, or both. Results A total of 54 of 207 patients had incomplete PVD (prevalence, 26.1%). Younger age and lattice degeneration were associated independently with incomplete PVD. After a mean follow-up of 5 years (range, 4 to 8 years), 16 patients (9.7%) experienced some adverse outcome. In 5 patients (2.7%), new retinal tears and 1 retinal Detachment developed. In 12 patients (7.6%), epimacular membranes developed. Patients with incomplete PVD at baseline experienced significantly more adverse outcomes than patients with complete PVD (Kaplan-Meier estimated probability and standard error, 19.2% and 0.061 vs 5.4% and 0.02; P = .01, log-rank test). Conclusions Up to one fourth of symptomatic, acute, and uncomplicated PVDs show incomplete Posterior Vitreous separation. Delayed complications related to PVD, like retinal tears and epimacular membranes, develop more frequently in patients showing incomplete PVD.
Michael R Martinez - One of the best experts on this subject based on the ideXlab platform.
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epiretinal membranes and incomplete Posterior Vitreous Detachment in diabetic macular edema detected by spectral domain optical coherence tomography
Investigative Ophthalmology & Visual Science, 2011Co-Authors: Avinoam Ophir, Michael R MartinezAbstract:PURPOSE. To present the vitreoretinal interface in diabetic macular edema (DME) associated with both epiretinal membrane (ERM) and incomplete Posterior Vitreous Detachment (PVD), as detected by spectral-domain optical coherence tomography (SD-OCT). METHODS. In a retrospective study, findings were analyzed in one eye in consecutive patients. Excluded were eyes that had undergone vitreoretinal intervention or that had complete PVD or complete Vitreous attachment. RESULTS. Of 44 eyes with DME and ERM, incomplete PVD was apparent in 23 (52.2%) eyes. A hyperreflective unified ERM/Posterior Vitreous cortex (PViC) membrane, or EVi membrane, was apparent in various sizes in 20 (87.0%) of the 23 eyes. This unified membrane (n = 20) was associated with vitreopapillary adherence in 19 (82.6%) of 23 eyes. Two major OCT presentations (n = 23) were encountered: incomplete vitreopapillary Detachment (n = 11; 25% of 44), with attachment to the macular ERM, and Posterior Vitreous Detachment from the macula, associated with vitreopapillary adhesion (n = 10; 22.7%), in four different manifestations. In the remaining two eyes, there was no association between the ERM and the PViC. CONCLUSIONS. In eyes with DME, ERM, and incomplete PVD, the Posterior cortical Vitreous and ERM appeared as one united EVi membrane in various lengths in most eyes, typically associated with vitreopapillary adhesion. These findings may have clinical importance in the context of epimacular membrane characteristics and its removal in DME.
Taiichi Hikichi - One of the best experts on this subject based on the ideXlab platform.
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Incidence of retinal breaks in eyes undergoing 23-gauge or 20-gauge vitrectomy with induction of Posterior Vitreous Detachment.
Retina (Philadelphia Pa.), 2012Co-Authors: Taiichi Hikichi, Shoko Kosaka, Kimitaka Takami, Hiroko Ariga, Hideo Ohtsuka, Makoto Higuchi, Takuro Matsushita, Reiko MatsushitaAbstract:PURPOSE To compare the incidence rates of retinal breaks in eyes in which Posterior Vitreous Detachment was induced during 23-gauge and 20-gauge vitrectomies to treat macular holes or preretinal membranes. METHODS We retrospectively reviewed 122 eyes of 115 patients with a macular hole or preretinal membrane who underwent induction of Posterior Vitreous Detachment during 23-gauge vitrectomy (23-gauge group) and 61 eyes of 58 consecutive patients with the disorders who underwent induction of Posterior Vitreous Detachment during 20-gauge vitrectomy performed by 1 surgeon. RESULTS No difference was found in the incidence rates of intraoperative retinal breaks between the 23-gauge (16% [20/122]) and 20-gauge (16% [10/61]) groups. A postoperative rhegmatogenous retinal Detachment developed in 2 (2%) eyes in the 23-gauge group, whereas no eyes in the 20-gauge group had postoperative retinal breaks or rhegmatogenous retinal Detachment. The incidence rates of retinal breaks in eyes with a macular hole and preretinal membrane did not differ significantly. CONCLUSION Posterior Vitreous Detachment induced during vitrectomy frequently results in intraoperative retinal breaks, the incidence of which may be independent of the gauge of the Vitreous instruments. Surgeons should be alert to the development of retinal breaks.
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intravitreal injection of hyaluronidase cannot induce Posterior Vitreous Detachment in the rabbit
Retina-the Journal of Retinal and Vitreous Diseases, 2000Co-Authors: Taiichi Hikichi, Masanori Kado, Akitoshi YoshidaAbstract:PURPOSE: To investigate whether intravitreal injection of hyaluronidase can induce Posterior Vitreous Detachment (PVD) in the rabbit. METHODS: One eye each of 12 New Zealand white rabbits received intravitreal injection via the pars plana of 20 IU of hyaluronidase (0.1 mL reconstituted in sterile balanced salt solution [BSS]) into the midVitreous cavity. The fellow eye of each rabbit received a Vitreous injection of 0.1 mL of BSS. At 3 and 6 months after intravitreal injection, four and eight rabbits were killed, respectively, and the eyes were enucleated. After fixation, scanning electron microscopy was performed to study the vitreoretinal interface. RESULTS: At 3 and 6 months after injection, scanning electron microscopy showed that the retinal surfaces in eyes that received either hyaluronidase or BSS were covered with Vitreous collagen fibers. No eyes, even those that received hyaluronidase over a period of 6 months, had the smooth retinal surface consistent with a bare internal limiting lamina that suggests the development of PVD. CONCLUSION: Hyaluronidase cannot induce PVD in the rabbit over a 6-month period after Vitreous injection.
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Posterior Vitreous Detachment induced by injection of plasmin and sulfur hexafluoride in the rabbit Vitreous
Retina-the Journal of Retinal and Vitreous Diseases, 1999Co-Authors: Taiichi Hikichi, Jun Akiba, Masanori Kado, Norihiko Yanagiya, Akitoshi YoshidaAbstract:PURPOSE To investigate whether an injection of plasmin and sulfur hexafluoride (SF6) can induce Posterior Vitreous Detachment (PVD) without vitrectomy. METHODS One eye each of 15 New Zealand white rabbits was assigned to one of three groups. Eyes in group 1 received a Vitreous injection of 1 unit of human plasmin (0.1 mL reconstituted in balanced salt solution) and 0.5 mL of SF6; eyes in group 2 received a Vitreous injection of plasmin alone; eyes in group 3 received a Vitreous injection of SF6 alone. Seven days after injection, all animals were monitored electroretinographically and killed, and the eyes were enucleated. After fixation, scanning electron microscopy was performed. RESULTS In group 1 eyes, the retinal surface was smooth except for the Vitreous base, which showed complete separation of the Vitreous cortex from the retina, indicating PVD. In group 2 and 3 eyes, sparse collagen fibers remained on the retinal surface. CONCLUSION Vitreous injection of plasmin combined with SF6 can induce PVD without vitrectomy.
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comparison of the prevalence of Posterior Vitreous Detachment in whites and japanese
Ophthalmic Surgery and Lasers, 1995Co-Authors: Taiichi Hikichi, Jun Akiba, Hiroyuki Hirokawa, Akihiro Kakehashi, Masanori Kado, Akitoshi Voshida, Clement L. TrempeAbstract:The Vitreous condition of healthy white (n = 551) and Japanese (n = 528) eyes were reviewed and compared with respect to the prevalence of Posterior Vitreous Detachment (PVD) in the two groups. No white or Japanese patient 39 years of age or younger had PVD; the prevalence among those older than 39 increased with age in the fifth through the ninth decades, i.e., respectively, to 4%, 24%, 37% 59%, and 87% in the whites, and to 5%, 21%, 43%, 72%, and 82% in the Japanese. In none of these decades was there any significant difference between the prevalence of complete or partial PVD in the whites and the Japanese. This finding is significant because the vitreoretinal relationship influences the development and prognoses of the various vitreoretinal disorders.
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relationship between floaters light flashes or both and complications of Posterior Vitreous Detachment
American Journal of Ophthalmology, 1994Co-Authors: Taiichi Hikichi, Clement L. TrempeAbstract:We examined biomicroscopically the Vitreous and retinal conditions of 902 consecutive symptomatic eyes (785 patients) to ascertain the relationship between floaters, light flashes, or both, and complications of Posterior Vitreous Detachment. Of 785 patients, 785 symptomatic eyes were divided as follows: group 1, 342 eyes with floaters alone; group 2, 240 eyes with floaters and light flashes; and group 3, 203 eyes with light flashes alone. We also studied 636 asymptomatic fellow eyes. The prevalence of Posterior Vitreous Detachment was significantly higher in groups 1 (138 of 342, 40%), 2 (214 of 240, 89%), and 3 (137 of 203, 67%) than in the asymptomatic eyes (127 of 636, 20%), in group 2 than in groups 1 and 3, and in group 3 than in group 1 (P = .01). The prevalence of retinal breaks in eyes with Posterior Vitreous Detachment was 5% (seven of 138), 13% (27 of 214), 12% (16 of 137), and 4% (five of 127) in groups 1, 2, 3, and the asymptomatic eyes, respectively; the prevalence was significantly higher in groups 2 and 3 than in asymptomatic eyes (P = .02 and P = .04) and group 1 (P = .04 and P = .05). The prevalence of Vitreous hemorrhage in eyes with retinal breaks was 71% (five of seven), 70% (19 of 27), and 6% (one of 16) in groups 1, 2, and 3, respectively. Of 117 patients with bilateral symptoms, 105 (90%) had the same symptoms and 104 (89%) had the same vitreoretinal relationship bilaterally.(ABSTRACT TRUNCATED AT 250 WORDS)
Akitoshi Yoshida - One of the best experts on this subject based on the ideXlab platform.
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intravitreal injection of hyaluronidase cannot induce Posterior Vitreous Detachment in the rabbit
Retina-the Journal of Retinal and Vitreous Diseases, 2000Co-Authors: Taiichi Hikichi, Masanori Kado, Akitoshi YoshidaAbstract:PURPOSE: To investigate whether intravitreal injection of hyaluronidase can induce Posterior Vitreous Detachment (PVD) in the rabbit. METHODS: One eye each of 12 New Zealand white rabbits received intravitreal injection via the pars plana of 20 IU of hyaluronidase (0.1 mL reconstituted in sterile balanced salt solution [BSS]) into the midVitreous cavity. The fellow eye of each rabbit received a Vitreous injection of 0.1 mL of BSS. At 3 and 6 months after intravitreal injection, four and eight rabbits were killed, respectively, and the eyes were enucleated. After fixation, scanning electron microscopy was performed to study the vitreoretinal interface. RESULTS: At 3 and 6 months after injection, scanning electron microscopy showed that the retinal surfaces in eyes that received either hyaluronidase or BSS were covered with Vitreous collagen fibers. No eyes, even those that received hyaluronidase over a period of 6 months, had the smooth retinal surface consistent with a bare internal limiting lamina that suggests the development of PVD. CONCLUSION: Hyaluronidase cannot induce PVD in the rabbit over a 6-month period after Vitreous injection.
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Posterior Vitreous Detachment induced by injection of plasmin and sulfur hexafluoride in the rabbit Vitreous
Retina-the Journal of Retinal and Vitreous Diseases, 1999Co-Authors: Taiichi Hikichi, Jun Akiba, Masanori Kado, Norihiko Yanagiya, Akitoshi YoshidaAbstract:PURPOSE To investigate whether an injection of plasmin and sulfur hexafluoride (SF6) can induce Posterior Vitreous Detachment (PVD) without vitrectomy. METHODS One eye each of 15 New Zealand white rabbits was assigned to one of three groups. Eyes in group 1 received a Vitreous injection of 1 unit of human plasmin (0.1 mL reconstituted in balanced salt solution) and 0.5 mL of SF6; eyes in group 2 received a Vitreous injection of plasmin alone; eyes in group 3 received a Vitreous injection of SF6 alone. Seven days after injection, all animals were monitored electroretinographically and killed, and the eyes were enucleated. After fixation, scanning electron microscopy was performed. RESULTS In group 1 eyes, the retinal surface was smooth except for the Vitreous base, which showed complete separation of the Vitreous cortex from the retina, indicating PVD. In group 2 and 3 eyes, sparse collagen fibers remained on the retinal surface. CONCLUSION Vitreous injection of plasmin combined with SF6 can induce PVD without vitrectomy.