- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Steady-state pattern electroretinogram and frequency doubling technology in anisometropic amblyopia
摘要： Background: Steady-state pattern electroretinogram (PERG) and frequency doubling technology (FDT) perimetry can be used to selectively investigate the activity of the M-Y ganglion cells in adult anisometropic amblyopes. Methods: Fifteen normal subjects (mean 27.8±4.1 years) and 15 adults with anisometropic amblyopia (mean 28.7±5.9 years) were analyzed using steady-state PERG and FDT. Results: The amplitude of steady-state PERG was significantly different not only among the control group and both the amblyopic eye (P=0.0001) and the sound eye group (P=0.0001), but also between the latter two groups (P=0.006). The difference in FDT mean deviation was statistically significant not only between the control group and amblyopic eye group (P=0.0002), but also between the control group and the sound eye group (P=0.0009). The FDT pattern standard deviation was significantly higher in the control group rather than in the amblyopic eye (P=0.0001) or the sound eye group (P=0.0001). A correlation was found between the reduction in PERG amplitude and the increase in FDT-pattern standard deviation index not only in amblyopic (P=0.0025) and sound (P=0.0023) eyes, but also in the healthy control group (P=0.0001). Conclusion: These data demonstrate that in anisometropic amblyopia, there is an abnormal functionality of a subgroup of the magnocellular ganglion cells (M-Y), and the involvement of these cells, together with the parvocellular pathway, may play a key role in the clinical expression of the disease.
关键词： frequency doubling technology perimetry,pattern electroretinogram,amblyopia,retinogeniculate pathways
更新于2025-09-23 15:21:01
-
Two Patterns of Interocular Delay Revealed by Spontaneous Motion-in-Depth Pulfrich Phenomenon in Amblyopes with Stereopsis
摘要： PURPOSE. To assess interocular delays in amblyopes with stereopsis and to evaluate the relationship between interocular delays and the clinical characteristics. METHODS. Twenty amblyopes with stereopsis (median, 400 arcseconds) and 20 controls with normal or corrected to normal visual acuity (≤0 logMAR) and normal stereopsis (≤60 arcseconds) participated. Using a rotating cylinder defined by horizontally moving Gabor patches, we produced a spontaneous Pulfrich phenomenon in order to determine the interocular delays, that is, the interocular phase difference at which ambiguous motion in plane was perceived. Two spatial frequencies—a low (0.95 cycles/degree [c/d]) and a medium (2.85 c/d) spatial frequency—were tested. RESULTS. The absolute interocular delays of the amblyopic group was significantly longer than that of the controls at both low or medium spatial frequencies (P < 0.01). However, the interocular delays was not always in favor of the fellow eye: 35% of the amblyopes (7/20) showed a faster processing of the amblyopic eye than that of the fellow eye at 0.95 c/d and 29.5% (5/17) at 2.85 c/d. No significant correlation was found between interocular delays and the clinical characteristics (e.g., age, treatment history, stereoacuity, and magnitude of anisometropia) in this amblyopic cohort. CONCLUSIONS. The interocular delays in amblyopes with stereopsis might result from either a faster or slower processing of the amblyopic eye relative to the fellow eye. This work provides important additional information for binocular processing of dynamic visual stimuli in amblyopia. However, the special role between this form of interocular delays and patients’ clinical characteristics remains unknown.
关键词： Pulfrich phenomenon,amblyopia,interocular delay
更新于2025-09-23 15:19:57
-
Photobiomodulation for the treatment of retinal diseases: a review
摘要： Photobiomodulation (PBM), also known as low level laser therapy, has recently risen to the attention of the ophthalmology community as a promising new approach to treat a variety of retinal conditions including age-related macular degeneration, retinopathy of prematurity, diabetic retinopathy, Leber's hereditary optic neuropathy, amblyopia, methanol-induced retinal damage, and possibly others. This review evaluates the existing research pertaining to PBM applications in the retina, with a focus on the mechanisms of action and clinical outcomes. All available literature until April 2015 was reviewed using PubMed and the following keywords: 'photobiomodulation AND retina', 'low level light therapy AND retina', 'low level laser therapy AND retina', and 'FR/NIR therapy AND retina'. In addition, the relevant references listed within the papers identified through PubMed were incorporated. The literature supports the conclusion that the low-cost and non-invasive nature of PBM, coupled with the first promising clinical reports and the numerous preclinical-studies in animal models, make PBM well-poised to become an important player in the treatment of a wide range of retinal disorders. Nevertheless, large-scale clinical trials will be necessary to establish the PBM therapeutic ranges for the various retinal diseases, as well as to gain a deeper understanding of its mechanisms of action.
关键词： low level laser therapy,age-related macular degeneration,retinopathy of prematurity,photobiomodulation,retinal degeneration,amblyopia,far-red to near-infrared,methanol toxicity,retinitis pigmentosa
更新于2025-09-10 09:29:36
-
Neutral-Density Filters Are Not a Patch on Occlusion
摘要： A number of studies over the past decade have shown that a neutral-density (ND) ?lter placed in front of an eye of a healthy adult can mimic certain aspects of amblyopic function, particularly those related to contrast sensitivity loss, binocular summation, and interocular imbalance. Furthermore, wearing a ND ?lter over the fellow eye of an amblyope can rebalance the dominance and, in some cases, recover stereoscopic function. Neutral-density ?lters reduce the mean luminance of scenes without perturbing the physical contrast. However, the contrast gain of visual neurons from retinal to cortex is dependent on the mean luminance. What this means is that the visual systems’ contrast sensitivity is modulated by the mean luminance even though the physical contrast is itself unaltered. Because it has recently been demonstrated that a rebalancing of the contrast between the eyes of amblyopes can lead to a restoration of binocular function, one might reasonably conclude that the rebalancing effects reported in amblyopes as a result of changes in interocular mean luminance (i.e., use of ND ?lters) are simply due to indirect changes in contrast sensitivity. This leads to the expectation that occlusion with a ND ?lter might provide a way to treat amblyopia and recover binocular function based on the contrast rebalancing principle. This could provide a simple alternative to that of lens blur if occlusion was the preferred approach over the alternative of contrast rebalancing using the dichoptic videogame training.
关键词： binocular function,amblyopia,ocular dominance,contrast sensitivity,neutral-density filters
更新于2025-09-09 09:28:46
-
The Relationship between Higher-order Aberrations and Amblyopia Treatment in Hyperopic Anisometropic Amblyopia
摘要： Purpose: To investigate the relationship between higher-order aberrations (HOAs) and amblyopia treatment in children with hyperopic anisometropic amblyopia. Methods: The medical records of hyperopic amblyopia patients with both spherical anisometropia of 1.00 diopter (D) or more and astigmatic anisometropia of less than 1.00 D were reviewed retrospectively. Based on the results of the amblyopia treatment, patients were divided into two groups: treatment successes and failures. Using the degree of spherical anisometropia, subjects were categorized into mild, moderate, or severe groups. Ocular, corneal, and internal HOAs were measured using a KR-1W aberrometer at the initial visit, and at 3-month, 6-month, and 12-month follow-ups. Results: The results of the 45 (21 males and 24 females) hyperopic anisometropic amblyopia patients who completed the 12-month follow-up examinations were analyzed. The mean patient age at the initial visit was 70.3 months. In total, 28 patients (62.2%) had successful amblyopia treatments and 17 patients (37.8%) failed treatment after 12 months. Among the patient population, 24 (53.3%) had mild hyperopic anisometropia and 21 (46.7%) had moderate hyperopic anisometropia. When comparing the two groups (i.e., the success and failure groups), ocular spherical aberrations and internal spherical aberrations in the amblyopic eyes were significantly higher in the failure group at every follow-up point. There were no significant differences in any of the HOAs between mild and moderate cases of hyperopic anisometropia at any follow-up. When the amblyopic and fellow eyes were compared between the groups there were no significant differences in any of the HOAs. Conclusions: HOAs, particularly ocular spherical aberrations and internal spherical aberrations, should be considered as reasons for failed amblyopia treatment.
关键词： Hyperopia,Amblyopia,Spherical aberration,Anisometropia,Higher order aberration
更新于2025-09-09 09:28:46
-
Is Suppression Just Normal Dichoptic Masking? Suprathreshold Considerations
摘要： PURPOSE. Amblyopic patients have a de?cit in visual acuity and contrast sensitivity in their amblyopic eye as well as suppression of the amblyopic eye input under binocular viewing conditions. In this study we wanted to assess the origin of the amblyopic suppression by studying the contrast perception of the amblyopic eye at suprathreshold levels under binocular and monocular viewing. METHODS. Using a suprathreshold contrast matching task in which the reference and target stimuli were presented to different eyes either simultaneously or successively, we measured interocular contrast matching in 10 controls and 11 amblyopes (mean age 35 6 15; 5 strabismics; 3 anisometropes; 3 mixed). This was then used as an index of the binocular balance across spatial frequency and compared against the contrast sensitivity ratio measured with the same stimuli. RESULTS. We observed that binocular matching becomes more imbalanced at high spatial frequency for amblyopes, compared with controls; that this imbalance did not depend in either group on whether the stimuli were presented simultaneously or successively; and that for both modes of presentation the matching balance correlates well with the interocular contrast sensitivity ratio (mean correlation coef?cient of the slopes R ? 0.7125). CONCLUSIONS. The results from our amblyopes show comparable losses of contrast perception at and above threshold under these binocular viewing conditions across a wide spatial frequency range, much stronger than that observed for our controls. This occurs under conditions in which there should be no dichoptic masking. Furthermore, the matching contrast could be well predicted by the monocular contrast sensitivity. Altogether, this suggests that amblyopic suppression cannot be explained by normal dichoptic masking but rather an attenuation of the input.
关键词： amblyopia,qCSF,suppression,contrast constancy,interocular matching
更新于2025-09-09 09:28:46
-
Phakic posterior chamber intraocular lens for unilateral high myopic amblyopia in Chinese pediatric patients
摘要： · AIM:Toassesstheoutcomesofposteriorchamberimplantablecollamerlens(ICL)implantationinChinesepediatricpatientswithunilateralhighmyopicamblyopia.·METHODS:Eleveneyesof11amblyopicpatientsaged11.02依3.34yunderwentICL(modelV4,StaarSurgicalInc.)implantationtotreatunilateralanisometropiawerestudied.Visualacuity,cycloplegicrefraction,contrastsensitivity,stereopsis,intraocularpressure(IOP),vaulting,cornealendothelialcellcountandcomplicationswereevaluated.Patientscompletedfollow-upat3d,1,3moandthelastfollow-uptime(mean8.18依2.82mo)aftersurgery.·RESULTS:Themeanmyopicanisometropiawas-13.70依3.25Dpreoperativelyand+0.69依2.63Dat8mopostoperatively.ThelogMARcorrecteddistancevisualacuity(CDVA)oftheamblyopiceyewas1.51依0.72preoperativelyand0.75依0.40at8mopostoperatively.ThelogMARCDVAat3d,1,3and8mopostoperativelyimprovedbyameanof0.64,1.55,1.82and2.64linesandgainedmorethan2linesaccountedfor18%,45%,45%,64%,respectively.Thecontrastsensitivityof0.5,1and2cpdinamblyopiceyeswassignificantlyincreasedaftersurgery.Nopatienthadnearstereopsisrecovery.Thevaultingat3and8mowassignificantlylowerthanthatat1mopostoperatively.Nootherpostoperativecomplicationswereobserved,exceptanintraoperativeoracutepupillaryblockglaucomahappenedinapatientattwoweekspostoperatively.·CONCLUSION:Thisshort-termresultsindicatethatICLimplantationcanbeapromisingalternativetherapyforhighmyopicanisometropicamblyopiainpediatricpatientswhohavefailedwithconventionaltreatmentsandnotsuitabletocornealrefractionsurgery.
关键词： amblyopia,myopicanisometropic,pediatricpatients,refractivesurgery,phakicintraocularlens
更新于2025-09-04 15:30:14