• <xmp id="1ykh9"><source id="1ykh9"><mark id="1ykh9"></mark></source></xmp>
      <b id="1ykh9"><small id="1ykh9"></small></b>
    1. <b id="1ykh9"></b>

      1. <button id="1ykh9"></button>
        <video id="1ykh9"></video>
      2. west china medical publishers
        Keyword
        • Title
        • Author
        • Keyword
        • Abstract
        Advance search
        Advance search

        Search

        find Keyword "Tomography, optical coherence" 259 results
        • The status and advances in the application of optical coherence tomography and optical coherence tomography angiography in Leber's hereditary optic neuropathy

          Leber hereditary optic neuropathy is an optic neuropathy associated with mitochondrial DNA. The disease affects young men mainly, which is considered to be due to denaturation of the retinal nerve ganglion cell and axonal loss of optic nerve, leading to optic atrophy. Nowadays, there are some development in studying Leber hereditary optic neuropathy by optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). It is great help to know the disease, forecast the progression of disease, and take action on intervention. In addition, there is a lack of in-depth study on OCT and OCTA characteristics among different mutation sites of LHON, different genders of the same site, different families of the same site or even different branches of the same family. It is expected to be improved in the future work.

          Release date:2021-04-19 03:36 Export PDF Favorites Scan
        • Spectral domain-optical coherence tomography analysis of choroid osteoma

          Objective To observe the image characteristics of eyes with choroidal osteoma using enhanced spectral domain optical Cirrus coherence tomography (SD-OCT), and to explore their relationship with visual acuity. Methods The records and SD-OCT images of 14 patients(18 eyes) diagnosed with choroidal osteoma at this hospital were reviewed retrospectively. All patients received examinations of best corrected visual acuity (BCVA), direct or indirect ophthalmoscope, slit lamp ophthalmoscope, fundus fluorescein angiography, B scan and/or computerized tomography. Subtle structure changes of the retina and choroidal osteoma were observed by four lines of the horizontal, the vertical scanning lines through the foveal and the tumor basal diameter under the model of five Line Raster.The correlation between the retinal and choroidal morphology and visual acuity was evaluated. Results The choroidal features of SD-OCT image of choroidal osteoma can be categorized into hyper-reflective in six eyes (33.3%), isoreflective in five eyes (27.8%), hypo-reflective in three eyes (16.7%) and mixing-reflective in four eyes (22.2%). The foveal thickness ranged from 50.2 to 245.1μm, and the average foveal thickness was (130.2±58.3) μm. The horizontal and vertical diameters of choroidal osteoma ranged from 5.6 to 15.8 mm and 4.6 to 12.8 mm respectively. The average horizontal and vertical diameters of choroidal osteoma were (7.8±2.9) mm and (6.5±2.5) mm respectively. The statistical analysis revealed that BCVA was not related to the horizontal, vertical diameters of choroidal osteoma or the foveal thickness (r=0.262, 0.229, 0.137; P=0.284, 0.294, 0.362). BCVA was related to the involvement of fovea and the integrity of photoreceptor inner/outer segment junction (IS/OS) (r=-3.838,-4.559; P=0.0015, 0.0003),but not related to macular choroidal neovascularization (CNV) or serous retinal detachment (r=-0.144, 0.411; P=0.684, 0.687). Conclusions The main SD-OCT image characteristics of eyes with choroidal osteoma was hyper-reflective and isoreflective. BCVA was not related to the horizontal, the vertical diameters of choroidal osteoma, the foveal thickness, macular CNV or serous retinal detachment. It was related to the involvement of fovea and the integrity of IS/OS.

          Release date:2016-09-02 05:22 Export PDF Favorites Scan
        • A clinical study of the position relationship between the optical fixation and the fovea in healthy adults

          ObjectiveTo observe the positional relationship between the central fixation point of the retina and the fovea in normal adults.MethodsA retrospective clinical study. From August 2019 to January 2020, 100 eyes of 100 normal adults who underwent physical examination at the Fourth People's Hospital of Shenyang were included in the study. All patients underwent BCVA, diopter, microfield, OCT examination, and axial length (AL) measurement. There were 42 males and 58 females with the average age was 46.4±14.7 years. The average diopter was -1.02±1.99 D, the average AL was 23.22±0.47 mm, the average foveal avascular zone (FAZ) area was 0.38±0.13 mm2. The MP-3 microperimetry was used for central fixation examination. After the examination, high-definition fundus images were automatically taken and the central fixation point of the retina were automatically calculated by the equipment. The Nidek Overlay functional multi-mode imaging platform was used to superimpose the images containing the central fixation point of the retina and the macular fovea, the positional relationship between the two was observed, and the distance between the two was measured. Pearson correlation analysis was performed on the distance between the fixation point of the center of the retina and the center of the fovea, age, diopter, and FAZ area of the macula.ResultsThe fixation point of the retinal center of all tested eyes was within the range of the macular fovea, which did not coincide with the center of the macular fovea. Among 100 eyes, the fixation point of the center of the retina were 53, 23, 15, and 9 eyes at the nose, lower, temporal, and upper sides, respectively. The average distance between the fixation point of the center of the retina and the center of the fovea was 158.31±71.56 μm. The distance between the fixation point of the retinal center and the center of the macular fovea and age (r=0.140), diopter (r=-0.009), FAZ area ( r=0.038) were not correlated (P=0.165, 0.932, 0.707) in correlation analysis.ConclusionThe central fixation point of normal adult retina is more common on the fovea nasal side.

          Release date:2020-12-18 07:08 Export PDF Favorites Scan
        • Clinical observation of microcystic macular edema before and after surgery for idiopathic epiretinal membrane

          ObjectiveTo observe the incidence and risk factors of microcystic macular edema (MME) in patients with idiopathic macular epiretinal membrane (IMEM) preoperatively and postoperatively. MethodsA retrospective case series study. From January 2017 to May 2021, 72 eyes of 72 patients with IMEM in Eye Hospital of Wenzhou Medical University at Hangzhou were included. There were 18 male and 54 female. Average age was 64.8±7.8 years. Eyes were all monocular. All patients received the examination of best corrected visual acuity (BCVA) by standard logarithmic visual acuity chart, which was represented logarithmic of minimum angle of resolution (logMAR). Optical coherence tomography was used to measure central macular thickness (CMT). MME was defined as small, vertically bounded cystic space located outside the fovea in the inner layer of the retina. According to the presence or absence of MME before surgery, the affected eyes were divided into two groups: non-MME group (35 eyes) and MME group (37 eyes). The difference of logMAR BCVA and CMT was statistically significant between Group A and B (t=3.117, 2.589; P=0.003, 0.012). All patients with IMEM were treated with 23G three-channels pars plana vitrectomy (PPV) with epiretinal membrane and inner limiting membrane (ILM) peeling. The two groups were further divided into four groups according to whether there was MME in the postoperative follow-up time. The group A1 was without MME before and after surgery, group A2 was without MME before surgery and with MME after surgery. The MME group was subdivided into the group with MME before surgery and without MME after surgery (group B1) and the group with MME before and after surgery (group B2). The mean follow-up time was 8.8±7.7 months. The same equipment and methods were used to exam the patients during the follow-up. Paired t test was used to compare the changes of MME, BCVA and CMT before and after surgery. The differences of CMT and BCVA among groups before and after surgery were compared by independent sample t test and one-way ANOVA. Logistic regression was used to analyze the influencing factors of MME before and after surgery, and multiple linear regression was used to analyze the influencing factors of postoperative BCVA. ResultsThere were 35 eyes in the non-MME group, 18 eyes (51.43%, 18/35) in the A1 group and 17 eyes (48.57%, 17/35) in the A2 group, respectively. There were 37 eyes in MME group, 6 eyes (16.22%, 6/37) in group B1 and 31 eyes (83.78%, 31/37) in group B2, respectively. At last follow-up, the logMAR BCVA was 0.10±0.12, 0.25±0.17, 0.09±0.11, 0.30±0.26 in group A1, A2, B1, and B2, respectively. Compared with the logMAR BCVA before surgery, the differences were statistically significant (t=3.779, 4.253, 7.869, 6.668; P<0.01). There was significant difference in logMAR BCVA among the four groups (F=4.460, P<0.01). There was a significant difference in logMAR BCVA between group A1 and group A2 (t=-2.930, P=0.006). There was no significant difference between group B1 and group B2 (t=-1.921, P=0.063). The CMT of group A1, A2, B1 and B2 were 371.83±73.24, 431.24±83.13, 407.00±28.07 and 425.19±70.97 μm, respectively. Compared with those before operation, the differences were statistically significant (t=5.197, 2.465, 3.055, 6.078; P<0.05). There was no significant difference in CMT among the four groups (F=2.597, P=0.059). Logistic regression analysis showed that pre-operation MME was correlated with pre-operation IMEM stage (β=1.494, P=0.004). New MME after surgery was correlated with age (β=0.153, P=0.013). Multiple linear regression analysis showed that postoperative visual acuity was significantly correlated with CMT before surgery and MME after surgery (β=0.001, 0.134; P=0.015, 0.019). ConclusionsPPV combined with epiretinal membrane and ILM peeling surgery for IMEM can improve visual acuity and decrease CMT. MME regress or regenerate after surgery. Age is an independent predictor of the risk of newly formed MME after surgery.

          Release date:2022-11-16 03:11 Export PDF Favorites Scan
        • The consistency and reproducibility of macular perfusion parameters in early diabetic retinopathy using optical coherence tomography angiography

          ObejctiveTo investigate the consistency and reproducibility of macular perfusion parameters in early diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA).MethodsA prospective cross-sectional observational study. Forty-six patients (46 eyes) diagnosed with mild nonproliferative DR were included in this study. There were 24 males and 22 females, with the mean age of 59.16±10.32 years. Two macular scan sizes of 3 mm×3 mm and 6 mm×6 mm were performed by the same operator, and the same test was performed by another operator. The superficial retinal layer (SRL) and deep retinal layer (DRL) in the foveal avascular zone (FAZ) and vessel density (VD) were quantified. The consistency of the two scan sizes and the reproducibility of the same scan size were also evaluated. The consistency was determined by the intraclass correlation coefficient (ICC). If the intraclass correlation coefficient (ICC)>0.80, consistency was good; if 0.4≤ICC<0.8, consistency was general; if ICC<0.40, consistency was poor.ResultsIn the 3 mm×3 mm and 6 mm×6 mm scanning sizes, the mean results of the two examiners were calculated. The FAZ of SRL were 0.39±0.13 mm2 and 0.42±0.15 mm2, FAZ of DRL were 0.74±0.22 mm2 and 0.89±0.23 mm2. The VD of SRL were (32.23±2.86)% and (31.91±3.01)%, VD of DRL were (43.73±4.64)% and (45.12±5.49)%. The consistency analysis showed that the ICC of SRL-FAZ and DRL-FAZ were 0.920 and 0.812, respectively; the ICC of VD were 0.833 and 0.830, respectively. The consistency was good. The reproducibility analysis of different examiners in the same scan size was better in the consistency of SRL FAZ and VD.ConclusionOCTA in two scanning sizes to measure FAZ and VD of early DR has good consistency and reproducibility.

          Release date:2018-07-23 04:02 Export PDF Favorites Scan
        • The thickness of the retina, choroid and sclera in different posterior sclera shape in high myopia

          Objective To observe the thickness of the retina, retinal nerve fiber layer (RNFL), choroid and sclera among the difference posterior sclera shape (PSS) in high myopia (HM). Methods Sixty HM patients (96 eyes) were enrolled in this study. There were 18 males (25 eyes) and 42 females (71 eyes). The mean age was (51.32±10.06) years. The mean spherical equivalent was (-14.38±6.31) DS. The mean axial length was (29.49±2.44) mm. The eyes were evaluated from deep range imaging optical coherent tomography (DRI-OCT) Atlantis 3D model, and divided as four groups include PSS-Ⅰ (27 eyes), PSS-Ⅱ (46 eyes), PSS-Ⅲ (11 eyes) and PSS-Ⅸ (12 eyes) according to the Curtin classification method. The thickness of the retina, RNFL, choroid and sclera were measured in the EDTRS Grid area. Results There were statistically significant differences in the thickness of retina of the central, first circle, second circle in the EDTRS Grid area among PSS-Ⅰ, PSS-Ⅱ, PSS-Ⅲ and PSS-Ⅸ groups (F=4.48, 5.03, 4.98; P<0.01). There was no statistically significant differences in the thickness of RNFL among four groups (F=0.13, P=0.93). There was no statistically significant differences in the central choroidal thickness (F=0.31, P=0.81). There were statistically significant differences in the first circle, second circle choroidal thickness among four groups (F=2.86, 2.96; P=0.04, 0.04). There was no statistically significant differences in the thickness of sclera under macular fovea among four groups (F=0.80, P=0.49). Conlusions There are changes of thickness of the retina, choroid present in the difference EDTRS Grid area among the difference PSS in HM, and changes in PSS-Ⅸ is most obvious.

          Release date:2017-11-20 02:25 Export PDF Favorites Scan
        • Analysis of macular choroidal thickness in children with occult high myopia

          ObjectiveTo observe and analyze the changes of macular choroidal thickness in children with occult high myopia and its influencing factors.MethodsA prospective, non-randomized, contemporaneous controlled trial. From September 2019 to October 2020, 56 children (110 eyes) who first visited the ophthalmic clinic of the Affiliated Hospital of Chengde Medical College without any myopia correction training were enrolled in this study. There were 33 males (64 eyes) and 23 females (46 eyes), with the average age of 8.62±1.87 years old; the age ranged from 6 to 12 years old. According to the clinical manifestations of myopia in children, they were divided into occult high myopia group (27 cases, 52 eyes) and control group (29 cases, 58 eyes). In the 52 eyes of the occult high myopia group, the spherical equivalent refraction (SER) of -0.00 to -1.00 D, >-1.00 to -2.00 D, >-2.00 to -3.00 D were 15, 16 and 21 eyes. Among 58 eyes in the control group, the SER of -0.00 to -1.00 D, >-1.00 to -2.00 D, >-2.00 to -3.00 D were 21, 18 and 19 eyes, respectively. The macular fovea within 6 mm was divided into three concentric circles centered on the macular fovea, which included the central area with a diameter of 1 mm, the inner ring area with a diameter of 1-3 mm, and the outer ring area with a diameter of 3-6 mm, totally 9 areas. The inner ring and outer ring were divided into upper, lower, nasal and temporal areas. The changes of choroidal thickness in each macular area of children in occult high myopia group and control group were observed. The choroidal thickness in each macular area was compared between the two groups using independent sample t-test. Pearson correlation analysis was used to analyze the correlation between mean foveal choroidal thickness and gender, age, intraocular pressure, ocular axis, diopter and corneal curvature in occult high myopia group.ResultsChoroidal thickness in macular area of children in occult high myopia group was thinnest in nasal side and thickest in temporal side. Compared with the control group, the mean choroidal thickness in the 9 macular zones of children in the occult high myopia group was significantly thinner than that in the control group, and the difference was statistically significant (P<0.05). The mean choroidal thickness in each macular region decreased with the increase of diopter in children with occult high myopia. Compared with the control group with the same spherical equivalent, there was no significant difference in the area above the inner ring and the outer ring of the macular fovea in the occult high myopia group of -0.00 to -1.00 D and the temporal side of the inner ring and the outer ring of the macular fovea in the occult high myopia group of >-2.00 to -3.00 D (P>0.05), but there were significant differences among the other regions (P<0.05). Pearson correlation analysis results showed that the average choroidal thickness of the fovea in children with occult high myopia was negatively correlated with age (r=-3.410, R2=11.630, P=0.010), eye axis (r=1.420, R2=2.016, P=0.030) and diopter (r=-2.680, R2=7.182, P=0.040), but not significantly correlated with gender (r=0.166, R2=0.028, P=0.240), intraocular pressure (r=0.330, R2=0.109, P=0.800) and corneal curvature (r=-0.260, R2=0.068, P=0.850).ConclusionsThe thickness of macular choroidal in children with occult high myopia is the thinnest on the nasal side of the macular fovea and the thickest on the temporal side of the macular fovea. The mean choroidal thickness in each region of the macular is thinner than that in the common myopia children with the same diopter. The mean choroidal thickness of fovea is negatively correlated with age, ocular axis and diopter.

          Release date:2021-01-16 10:10 Export PDF Favorites Scan
        • Correlation of inner-retinal irregularity index with visual function before and after surgery in idiopathic macular epiretinal membrane

          ObjectiveTo observe the changes of the inner-retinal irregularity index (IRII) of eyes with idiopathic macular epiretinal membrane (IMEM) before and after surgery and its correlation with visual function.Methodsretrospective series of studies. From March 2017 to May 2018, 46 IMEM patients (46 eyes) diagnosed in the Department of Ophthalmology of Central Theater Command General Hospital were included in the study. BCVA, visual deformation degree (M), OCT inspection with swept source were all performed. The BCVA examination was carried out using the international standard visual acuity chart, which was converted into logMAR visual acuity for record. The average IRII was 1.255±0.048, the average logMAR BCVA was 0.63±0.21, the average M value was 0.68±0.38, the average of central macular thickness (CMT) was 353.57±73.92 μm, the average inner retinal layer thickness (IRT) was 181.50±40.91 μm. The complete and incomplete ellipsoid zone (EZ) were 17 and 29 eyes, respectively. All eyes underwent a 25G three-incision closed vitrectomy through the flat part of the ciliary body, and the epiretinal membrane and inner limiting membrane were removed at the same time. The changes of IRII, M value, BCVA, CMT, IRT and EZ were observed at 1, 3, 6, and 12 months after surgery, and the correlation were analyzed between IRII and M value and BCVA before and after surgery. Single-factor repeated measurement data analysis of variance was used for the comparison of BCVA, M value, CMT, and IRT before and after surgery. Spearman rank correlation analysis were adopted for the correlation analysis between IRII and BCVA, M value, CMT, IRT and EZ integrity before and after surgery.ResultsTwelve months after surgery, the average IRII and logMAR BCVA were 1.175±0.032 and 0.47±0.16, respectively. Compared with those before surgery, they were significantly improved, and the difference was statistically significant (F=22.273, 5.453; P<0.001, <0.001). The average M value (F=20.109), CMT (F=14.273), IRN (F=13.665) were significantly lower than those before the operation, and the difference was statistically significant (P<0.001, 0.001, <0.001). The integrity of EZ was significantly improved compared with that before surgery, and the difference was statistically significant (χ2=12.715, P<0.001). The results of correlation analysis showed that preoperative IRII was positively correlated with preoperative M value and CMT (r=0.951, 0.701; P<0.001, <0.001). It was positively correlated with postoperative M value, logMAR BCVA, CMT and EZ integrity (r=0.650, 0.369, 0.720, 0.293; P<0.001, <0.001, P=0.048). It was not correlated with preoperative logMAR BCVA and EZ integrity (r=0.283, 0.001; P=0.056, 0.996).ConclusionThe IRII of IMEM eyes before surgery is significantly correlated with the BCVA and M values after surgery.

          Release date:2020-12-18 07:08 Export PDF Favorites Scan
        • Macular morphological changes of choroidal melanoma with optical coherence tomography after plaque radiotherapy

          Objective To observe the macular morphological changes of choroidal melanoma with coherence tomography (OCT) after plaque radiotherapy (PRT). Methods A total of 48 patients (48 eyes) with choroidal melanoma who underwent125I PRT were enrolled in this study. All the patients were examined documenting OCT to get the image of macula. The macula of all the patients was not involved. The median visual acuity was 0.4plusmn;0.2, which ranged from 0.02 to 1.0. There were 18 eyes (37.5%) with retinal detachment, 12 eyes (25.0%) with retinal pigment epithelium (RPE) changes, seven eyes (14.6%) with macular edema, epimacular membrane, detachment combined with edema, exudation and RPE changes, 11 eyes (22.9%) with normal macular structure. The median follow-up time was (10.4plusmn;5.9) months, which ranged from one to 24 months. The tumor control situation and visual acuity were observed in follow-up period. The same equipment and methods of OCT were used to return visit in follow-up period. The macular morphological changes at the final visit and its relationship with PRT and visual acuity were contrastively analyzed. Results All the patients had good control of tumor. The vision acuity improved in two eyes (4.2%), unchanged in 10 eyes (20.8%), and decreased in 36 eyes (75.0%). The differences of the visual acuity was statistically significant between before and after treatment (Z=-3.778,P<0.05). There were 13 eyes (27.1%) with retinal detachment; nine eyes (18.8%) with RPE changes; 17 eyes (35.4%) with macular edema, detachment combined with edema, exudation and RPE changes; six eyes (12.5%) with proliferation, atrophy, detachment combined with edema, exudation and epimacular membrane;three eyes (6.3%) with normal macular structure. There were 15 patients (31.3%) with two or more abnormal macular morphology after PRT. Conclusions Retinal detachment, RPE changes, macular edema and exudation are common abnormal macular morphology after PRT. The incidence rate of abnormal macular morphology is increased. There are 31.3% patients with two or more abnormal macular morphology.

          Release date:2016-09-02 05:26 Export PDF Favorites Scan
        • Optic disc drusen: a review

          Optic disc drusen (ODD) is an acellular deposit located in front of the cribriform of the optic disc. ODD has been much underdiagnosed due to few obvious clinical symptoms. These clinical symptoms are easily confused with optic disc edema caused by systemic high-risk diseases. The current mainstream view is that optic nerve fiber axon metabolism is disordered, leading to intracellular mitochondrial calcification. After axon chronic disintegration, calcified mitochondria continuously release outside the cell, resulting in a much higher concentration of extracellular calcium than inside the cell. The continuous deposit and accumulation of extracellular calcification fuse to small calcified corpuscles, which lead to ODD formation. OCT enhanced deep imaging can detect ODD sensitively, and its image feature is a weak reflection core completely or partially surrounded by a strong reflection edge. ODD is one of the common causes for optic disc crowding. During adolescence, the accumulating calcified bodies buried in the deep optic disc gradually extrude and migrate to the superficial optic disc, which turn into superficial ODD. As a consequence, part of these ODD patients rapidly progress during adolescence and generally become stable in adulthood with anterior ischemic optic neuropathy, or other vascular complications.

          Release date:2020-09-22 04:09 Export PDF Favorites Scan
        26 pages Previous 1 2 3 ... 26 Next

        Format

        Content

      3. <xmp id="1ykh9"><source id="1ykh9"><mark id="1ykh9"></mark></source></xmp>
          <b id="1ykh9"><small id="1ykh9"></small></b>
        1. <b id="1ykh9"></b>

          1. <button id="1ykh9"></button>
            <video id="1ykh9"></video>
          2. 射丝袜