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find Keyword "coherence" 400 results
  • Imaging features of ultra-wide field fundus autofluorescence in multiple evanescent white dot syndrome

    Objective To observe the imaging features of ultra-wide field short wave fundus autofluorescence (SW-FAF) in eyes with multiple evanescent white dot syndrome (MEWDS), and analysis the correspondence to conventional images. Methods It was a retrospective case series study. Thirteen patients (14 eyes) diagnosed with MEWDS were enrolled. There were 12 females and 1 male, aged from 22 to 57 years, mean age was 34.5 years. All the eyes underwent fundus color photography, optical coherence tomography (OCT) and ultra-wide field autofluorescence (FAF). Simultaneous fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA) were performed in 6 eyes. The characteristic changes of SW-FAF in studied eyes were observed and compared with the images of FFA and ICGA. All the eyes were followed up every 1 to 2 weeks, with an average of 16.7 weeks. The characteristic images of SW-FAF and corresponding OCT were studied during follow up. Results MEWDS presented with numerous multiple hyper-autofluorescent spots, sized from 50-500 μm, with a vague boundary in ultra-wide field SW-FAF. These spots located mainly at the peripapillary area and the posterior pole with a confluent pattern. The lesions extended to the mid-peripheral retina as well and became more scattered. The distribution of the hyper-autofluorescent lesions in SW-FAF corresponded roughly to that of the greyish-white spots seen in color photograph and the hyper-fluorescent spots detected by FFA. It was consistent with the distribution of hypo-fluorescent spots in late-phase ICGA as well. But the number of the spot showed in FAF is much more than that in FFA, and slightly less than that in ICGA. The OCT scans through the hyper-autofluorescent lesions in SW-FAF showed impairment of outer retina. After the recovery, the hyper-autofluorescent spots disappeared with the outer retina structure repaired completely. Conclusions MEWDS presented with numerous multiple hyper-autofluorescent spots which located mainly at the peripapillary area in ultra-wide field SW-FAF. The distribution of the hyper-autofluorescent lesions in SW-FAF corresponded roughly to color photograph, FFA and ICGA in late-phase. The OCT scans through the hyper-autofluorescent lesions in SW-FAF showed impairment of outer retina.

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  • Research progress of optical coherence tomography angiography in retinal vein occlusion

    Retinal vein occlusion (RVO) is a vascular disease characterized by intraretinal hemorrhage, edema and hard exudation, which is caused by increased retinal vein pressure. OCT angiography (OCTA) has been widely used in the diagnosis of retinal vascular diseases including RVO by virtue of non-invasive, high resolution and stratified display of superficial, deep retinal vessels and quantification of retinal vessel density and non-perfusion area size. OCTA can provide information of retinal microvascular structure and blood perfusion under the condition of disease, it also can be used to evaluate the effect of treatment and changes of retinal circulation during the course of disease follow-up. Although OCTA cannot replace fundus angiography completely, it has brought us more information about the pathogenesis, disease progression and prognostic factors of RVO. It is believed that with the progress of technology, OCTA will bring us a new chapter in the study of retinal vascular diseases including RVO.

    Release date:2019-07-16 05:35 Export PDF Favorites Scan
  • Morphological characteristics and correlation of dome-shaped macula with macula hole in high myopia

    ObjectiveTo observe the morphological characteristics of dome-shaped macula (DSM) and macular hole (MH) in high myopia by optical coherence tomography (OCT), to further explore the correlation between DSM and MH. MethodsA retrospective case-control study. From April 2021 to December 2023, 963 eyes of 503 patients with high myopia (myopic diopter ≥6.00 D) in Department of Ophthalmology of the Fourth Hospital of Hebei Medical University were enrolled in the study. The age of patients ranged from 5 to 89 years old, with the mean age of (48.91±16.69) years. Diopter was −6.00 to −26.00 (−10.49±3.15) D. All eyes were examined by OCT. The width and height of DSM, subfoveal choroidal thickness (SFCT), inner port diameter and base diameter of MH were measured by software on OCT. According to the OCT image features, DSM was divided into horizontal and vertical oval-shaped DSM, and symmetrical round DSM. According to the presence or absence of DSM, the eyes were divided into DSM group and non-DSM group. Then, the affected eyes with MH were divided into DSM with MH group and non-DSM with MH group. The incidence of DSM, the incidence of MH in the DSM group and the non-DSM group, the inner port diameter of MH, the base diameter of MH, SFCT, and the location of retinoschisis (RS) in the DSM with MH group and the non-DSM with MH group were observed. Independent sample t test or non-parametric Mann-Whitney U test was used for comparison between groups. Pearson correlation analysis was used to analyze the related factors of MH inner port diameter, base diameter and DSM width, height, height/width ratio. ResultsAmong the 963 eyes, the DSM group and the non-DSM group were 266 (27.6%, 266/963) and 697 (72.4%, 697/963) eyes. Compared with the non-DSM group, patients in the DSM group were older (Z=−11.302), had higher degree of myopia (Z=−8.944), thinner SFCT (Z=−16.244), and higher incidence of MH (χ2=8.828), and the differences were statistically significant (P<0.05). Compared with non-DSM with MH group, the patients in DSM with MH group were older (t=2.610), higher myopia diopter (t=3.593), and thinner SFCT (t=3.505), the differences were statistically significant (P<0.05). There was no significant difference in the number of eyes in the epiretinal membrane between the two groups (χ2=0.119, P=0.730). In the DSM with MH group, RS mostly occurred in the outer retina with a large range, while in the non-DSM with MH group, RS mostly occurred in the outer and inner retina with a small range. There was a statistically significant difference in the number of eyes at different positions of RS between the two groups (χ2=25.131, P<0.05). The results of correlation analysis showed that there was no correlation between the inner port and base diameter of MH and the width, height, height/width ratio of DSM (P>0.05). ConclusionsCompared with high myopia patients without DSM, patients with DSM are older, have more severe myopia and thinner SFCT. In DSM patients with MH, RS often occurs in the outer retina and has a large range. There was no significant association between DSM morphology and MH size.

    Release date:2025-02-25 09:39 Export PDF Favorites Scan
  • The status in the mechanism and significance of the hyperreflective foci in macular edema by optical coherence tomography

    Macular edema is an important cause of visual impairment in many eye diseases such as diabetic retinopathy, retinal vein occlusion and uveitis. Optical coherence tomography (OCT) provides high-resolution image of retinal microstructures in a non-contact and rapid manner, which greatly improves the ability of diagnosis and follow-up to macular edema patients. OCT has been widely used in the clinical detection of patients with macular edema. No matter what the cause of macular edema is, it can be observed in OCT images that there are spot-like deposits with strong reflection signals in the retina, which are mostly distributed discretely or partially convergent, and are called hyperreflective foci. At present, the nature or source of hyperreflective foci is not clear, however, may involve the destruction of the blood retina barrier, retinal inflammatory reaction, neurocellular degeneration, and so on. These mechanisms are also the key physiological mechanisms in the development of macular edema. The clinical research on hyperreflective foci provides a new direction for understanding the pathogenesis of macular edema and predicting the prognosis of macular edema. The distribution and quantity characteristics of hyperreflective foci may be an important biological marker to predict the prognosis of macular edema.nosis of macular edema. foci provides a new direction for understanding the pathogenesis of macular edema and predicting the prognosis of macular edema. The distribution and quantity characteristics of HRF may be an important biological marker to predict the prognosis of macular edema.

    Release date:2021-08-19 04:11 Export PDF Favorites Scan
  • The pathological changes of central retinal artery occlusion with Optical coherence tomography

    ObjectiveTo observe the pathological changes of central retinal artery occlusion (CRAO) by optical coherence tomography (OCT).MethodsFifty-three eyes of 53 patients who were diagnosed as CRAO in our center between January 2001 to January 2004 underwent the examination by OCT. The intervals between the disease onset and OCT examination were less than 2 weeks. The scan modes of OCT were horizontal or vertical line scan. The locations of scanning were macular, posterior pole of retina, optical papilla and the focus of bleeding or exudation.ResultsThe OCT pathological changes of CRAO in vivo includes increase of retinal thickness and reflex of retina, width of dark layer of photoreceptor (edema), edema or cystoid edema of fovea, retinal bleeding, cotton-wool spot and papilla edema. Four patients who had ciliary retinal artery showed normal retinal structure in the supply region of ciliary retinal artery.ConclusionOCT can display the pathological changes of retinal tissues in CRAO in vivo, especially on the old patients or the patients with systemic disease who were contraindicated by FFA. The unique OCT image of pathological changes of CRAO supply the objective signs for the instant clinical diagnosis.(Chin J Ocul Fundus Dis, 2005,21:74-78)

    Release date:2016-09-02 05:52 Export PDF Favorites Scan
  • Correlations between the thickness of foveal ganglion cell-inner plexiform layer and visual field defect in patients of sellar region tumors with optic chiasmal compression before and after gamma knife treatment

    ObjectiveTo observe the correlation between the thickness of foveal ganglion cell-inner plexiform layer (GCIPL) and visual field mean defect before and after gamma knife treatment in patients of sellar region tumors with optic chiasmal compression. MethodsThis was a prospective case series. 72 eyes of 37 consecutive patients suffering from optic chiasmal compression of sellar region tumors treated with gamma knife were enrolled in the study. According to the change of visual field before and after gamma knife treatment, the patients were divided into three groups. There were 13 eyes of 7 patients in group 1 with no vision defect pre-and post-treated, 34 eyes of 17 patients in group 2 with improvement of visual field defect after treatment, 25 eyes of 13 patients in groups 3 with no improvement or reorganization of visual field defect after treatment. Overall average thickness of GCIPL, and of the superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal retina were measured with the Cirrus high-definition spectral domain optical coherence tomography, and mean deviation (MD) with the Humphrey field analyzer before and 6 months after treatment. There was no significant difference in MD values between group 2 and 3 pre-treated (t=1.471, P=0.084). There was significant difference between all the groups in total average value of GCIPL thickness and the 6 quadrant GCIPL thickness values pre-treated (P < 0.05). Logistic regression model was applied to analysis of the correlation between GCIPL thickness and the improvement of visual field after treatment. ResultsThe MD values of the group 1, 2 and 3 were (-2.96 ±0.75), (-10.24 ±1.31), (-20.2 ±5.88) dB at 6 months after treatment. There was significant difference between group 2 and 3 of MD value after treatment (t=6.974, P=0.000). In group 1, there was no significant difference in mean GCIPL thickness and the 6 quadrant GCIPL thickness values between pre-and post-treated (t=0.882, P=0.395).The mean thickness of GCIPL, superonasal and inferonasal GCIPL was increased than pre-treated in group 2, and the difference was statistically significant (t=2.438, 4.630, 4.457; P=0.035, 0.001, 0.001). The mean thickness of GCIPL, superonasal and inferonasal GCIPL was decreased than pre-treated in group 3, and the difference was statistically significant (t=-2.387, -4.603, -4.975; P=0.041, 0.002, 0.001).Logistic regression analysis showed that the greater of the value of average GCIPL thickness of patients with visual field defect pre-treated, the higher of the proportion of patients with improvement of visual field defect post-treated. There was a significant correlation between the value of superonasal or inferonasal GCIPL and the improvement of the visual field post-treated (OR=5.374, 4.693; P=0.000, 0.000). There was no significant correlation between the value of superotemporal or upper or lower or inferotemporal GCIPL and the improvement of the visual field post-treated (OR=1.058, 1.101, 1.074, 1.056; P=0.183, 0.080, 0.162, 0.186). ConclusionsIn patients with optic chiasmal compression of sellar region tumor, the greater of the average GCIPL thickness pre-treated, the higher of the proportion of patients with improvement of visual field defect post-treated. There was a significant correlation between superonasal or inferonasal value of the GCIPL thickness and the improvement of visual field defect post-treated.

    Release date:2016-11-25 01:11 Export PDF Favorites Scan
  • Macular thickness measurement of six-year-old children and analysis of its relevant factors

      Objective  To observe the distribution of macular thickness and its relationship with axial length, gender, refraction status and race in six-year-old children. Methods 1543 six-year-old children from 34 schools in Sydney were randomly selected. The thickness of center macula(CM), inner macula(IM)and outer macula(OM)were measured by optical coherence tomography(OCT), the differences of macular thickness between different genders and races were comparatively analyzed. The axial length and refraction status of all children were measured by IOL Master and autorefractor RK-F1 respectively. Results The CM, IM and OM thickness of all those six-year-old children were normally distributed,on average they were 193.6, 264.3 and 236.9 mu;m respectively,the differences were statistically significant(t=0.40,0.08,0.20;P<0.05). The CM,IM and OM average thickness was 194.2,264.9,229.0 mu;m for boys and 189.3,262.5,231.5 mu;m for girls respectively. CM and IM thickness of boys were thicker than those in girls(t=0.15,0.11;P<0.05). The CM,IM and OM average thickness was 196.0,265.2,237.5 mu;m for White kids,186.0,262.3,236.5 mu;m for East Asia kids and 19.4,263.7,233.8 mu;m for Central East kids respectively. The CM and IM thickness of White and Central East children were significantly thicker than East Asia children (t=0.12,0.15;Plt;0.05). There was no difference between these three races in OM thickness(t=0.16,P=0.6). The IM and OM were thinner with longer axial length (Plt;0.05). The CM,IM and OM thickness was thicker with higher hyperopic degrees (Plt;0.05). Conclusions Macular thickness was normally distributed in six-year-old children and was significantly affected by gender, race, axial length and refraction status.

    Release date:2016-09-02 05:41 Export PDF Favorites Scan
  • Correlation between macular microstructure changes and visual outcome before and after scleral buckling for macular-off primary rhegmatogenous retinal detachment

    ObjectiveTo evaluate the correlation between macular microstructure changes and visual outcome before and after scleral buckling for macular-off primary rhegmatogenous retinal detachment (RRD). MethodsA total of 43 eyes in 43 patients with RRD were enrolled in this retrospective study. All patients underwent scleral buckling and the retina was successfully reattached. Best corrected visual acuity (BCVA) and spectral domain optical coherence tomography (SD-OCT) were measured for all patients before and at 3 days, 1, 3 and 6 months after surgery. The height of subretinal fluids (SRF), the thickness of retinal neurosensory layer in foveal, and the thickness of outer nuclear layer (ONL) were measured. The microstructure changes of external limiting membrane (ELM), junction line and intermediate line of photoreceptor inner segment/outer segment (IS/OS) were observed. The correlation between morphologic changes in the macular foveal and BCVA on 6 months after surgery were also analyzed. ResultsThe mean preoperative BCVA was 1.18±0.93. The detached retinas had 3 types of SD-OCT images, including normal foveal contour without edema, diffuse edema with ONL cystoids cavities, diffuse edema with ONL cystoids cavities and wave-like ONL. The mean preoperative SRF height was (885.05±493.28) μm. The preoperative mean thickness of retinal neurosensory layer in foveal and ONL in the RRD eyes were thinner than the healthy fellow eyes (t=2.642, 1.895;P < 0.05). The fluids and cystoids cavities were absorbed, retina reattached in all the RRD eyes at 3 days after surgery. SRF had been detected in 100.0%, 93.0%, 77.8%, 46.5% RRD eyes on 3 days, 1 month, 3 months and 6 months after surgery, with heights of (219.00±117.02), (163.51±72.83), (101.27±64.47), (55.69±21.15) μm respectively. There were 3 patterns of residual SRF: diffuse, subfoveal multi-bleb, subfoveal single bleb. Compared with the healthy fellow eyes, there were significant differences in the mean thickness of foveal neurosensory layer (t=-10.658, -8.550, -6.955) and ONL thickness (t=-6.240, -5.424, -3.326, -3.323) at 3 days, 1 month, 3 months and 6 months after surgery(P < 0.05), except for the thickness of foveal neurosensory layer at 6 months after surgery (t=-2.186, P=0.570). The reattached retinas had 4 types of SD-OCT images, including: (1) disrupted ELM, IS/OS line and intermediate line; (2) intact ELM with disrupted IS/OS line and intermediate line; (3) intact ELM and IS/OS line with disrupted intermediate line; (4) intact ELM, IS/OS line and intermediate line. The mean postoperative BCVA at different time points were better than preoperative BCVA (t=-3.12, -4.89, -5.03, -4.53; P < 0.05). The postoperative BCVA of eyes with intact IS/OS was different from that of eyes with disrupted IS/OS at 6 months after surgery (t=2.609, P < 0.05). The preoperative SRF height, thickness of foveal neurosensory layer and ONL were correlated with the BCVA at 6 months after surgery (r=0.817, 0.028, 0.521; P < 0.05). ConclusionsMacular-off RRD eyes had SRF, thinner foveal neurosensory layer and ONL before and after scleral buckling. The disruption of ELM, IS/OS junction line and intermediate line can be seen in most of RRD patients. The thinner foveal neurosensory layer and ONL were correlated with the slow recovery of postoperative BCVA.

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  • Characteristics of spectral-domain optical coherence tomography of drusen in atrophic age-related macular degeneration

    ObjectiveTo observe the morphologic characteristics of drusen in atrophic age-related macular degeneration (AMD) by spectral domain optical coherence tomography (SD-OCT). MethodsFifty-four patients (84 eyes) with macular drusen and atrophic AMD, and 56 age-matched control patients (56 eyes) with cataract were included in this study. Atrophic AMD patients were divided into two groups: D1 group with drusen involving the fovea (42 eyes) and D2 group with drusen not involving the fovea (42 eyes). The SD-OCT images in macular (6 mm×6 mm scans) were acquired, and the foveal retinal thickness (FRT) was measured. The size, morphology, inner reflection, homogeneity of drusen and its relationship with surrounding tissues were analyzed. ResultsThe FRT of D1 group, D2 group and control group were (160.90±38.47), (194.21±26.11), (222.42±19.29) μm respectively. The FRT of D1 group and D2 group were thinner than that of control group (F=57.08, P=0.00). Totally 1124 drusen were found by SD-OCT images in 84 eyes, with an average of 10.84 drusen in each eye. 3.0%, 12.5% and 84.5% of all 1124 drusen were small, medium and large sized respectively. 56.6%, 14.2%, 20.4% and 8.8% of all drusen were dome, pointed, saw-toothed and basal-shaped respectively. 17.1%, 57.5% and 25.4% of all drusen had low, medium and high internal reflectivity respectively. The internal reflectivity of 65.6%, 2.8% and 31.7% of all drusen were homogeneous, nonhomogeneous with core, and nonhomogeneous without core respectively. Overlying retinal pigment epithelium (RPE) damage and photoreceptor inner segment/outer segment (IS/OS) junction damage were presented in 34.5% and 24.8% drusen respectively. The most common type of drusen was dome-shape, homogeneous, with medium internal reflectivity, and without overlying RPE or IS/OS junction damage (81.0%). ConclusionsThe FRT becomes thinner in patients with drusen. The most common drusen types are dome-shaped, homogeneous, with medium internal reflectivity, and without overlying RPE or IS/OS junction damage.

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  • The fast blood flow density of intermediate choroid in endogenous Cushing syndrome: analysis of optical coherence tomography angiography

    ObjectiveTo compare the fast blood flow density (FBFD) of intermediate choroid between endogenous Cushing syndrome (ECS) patients and healthy control subjects.MethodsThirteen eyes of 7 eligible ECS patients (ECS group) and 13 eyes of 7 gender, age, axial length matched healthy volunteers (control group) were enrolled in this study. For each subject, macular radial scan with swept source optical coherence tomography (SS-OCT) was performed and subfoveal choroidal thickness (SCT) was measured. Then 3.0 mm×3.0 mm macular scan with SS-OCT angiography was performed, and selected blood flow image at intermediate choroid level or 1/2 SCT beneath Bruch membrane. The grayscale images were then binarized for the analysis of FBFD.ResultsThe SCT in ECS group was (394.7±77.7) μm, which was significantly thicker than (332.1±68.1) μm in control group (t=2.923, P=0.008). The FBFD of intermediate choroid in ECS group were (76.35±14.46)%, which were significantly greater than (63.57±13.42)% in control group (t=2.775, P=0.01).ConclusionECS patients had increased FBFD at intermediate choroid level compared with healthy controls.

    Release date:2017-07-17 02:38 Export PDF Favorites Scan
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