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find Keyword "光学相干断层扫描" 31 results
  • Optical coherence tomography in macular edema

    Objective To observe the characteristics of the images of optical coherence tomography (OCT) performed on the patients with macular edema, and investigate relationship between the retinal thickness at the central fovea and the best corrected visual acuity. Methods Fourty-seven patients (54 eyes) with macular edema diagnosed by direct and indirect ophthalmoscopy, three mirror contactlens, or fundus fluorescein angiography (FFA) underwent OCT which was also performed on 50 healthy individuals as the control. The examination focused on the horizontal and vertical planes crossing the central fovea to measure the thickness of the fovea. The correlation between retinal thickness at the central fovea and best-corrected visual acuity was analyzed, and the images of OCT in the patients with macular edema were classified according to the macular configuration. Results Significant difference of the macular configuration and best-corrected visual acuity was found between the control and macular edema group. Three characteristics were found in the images of OCT in the patients with macular edema: sponge-like retinal swelling in 20 eyes (37.1%), macular cystoid edema in 26 eyes (48.1%), and serous retinal detachment in 8 eyes (14.8%). The statistical analysis showed that there was a negative correlation between the thickness at the central fovea and best-corrected visual acuity of affected eyes (r=-0.569, P=0.000). Conclusions The images of OCT in macular edema include 3 types: sponge-like retinal swelling, macular cystoid edema, and serous retinal detachment. The retinal thickness at the central fovea of the eyes with macular edema was thicker than that of the normal ones, and the thicker the fovea is, the poorer the visual acuity will be. (Chin J Ocul Fundus Dis,2004,20:152-155)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • Anatomic evaluation of vitreous surgery of idiopathic macular hole with optical coherence tomography

    Purpose To evaluate the surgical effect of idiopathic macular hole (IMH),with optical coherence tomography (OCT). Methods To measure the diameter of holes and hole halos,the thickness of hole in edge,the changes of hole pattern in 19 cases (19 eyes) with IMH using OCT. Results By quantitatively measuring,OCT showed that after surgery the mean hole diameter lessened from (570.95plusmn;264.59 )mu;m to (337.05plusmn;335.95)mu;m.The mean diameter of hole halo lessened from (1043.53plusmn;278.80)mu;m to (695.00plusmn;483.00)mu;m and the mean thickness of the hole edge thinned from (389.78plusmn;60.58)mu;m to (298.78plusmn;109.80)mu;m.In 17 eyes the holes become closed or reduced in size or the hole halo,and thinned in hole edge.The anatomic successful rate of the surgery is 89%. Conclusion OCT can objectively,accurately and effectively judge the anatomic effect of IMH surgery. (Chin J Ocul Fundus Dis,2000,16:71-138)

    Release date:2016-09-02 06:05 Export PDF Favorites Scan
  • Retinal vascular characteristics in patients with obstructive sleep apnea syndrome assessed by optical coherence tomography angiography: a meta-analysis

    Objective To evaluate the application value of optical coherence tomography angiography (OCTA) in obstructive sleep apnea syndrome (OSAS). Methods A comprehensive search of both domestic and international databases was conducted to identify clinical studies on the use of OCTA in OSAS, from the establishment of the databases to May 2024. A meta-analysis was performed using Revman 5.4 software. Results A total of 134 studies were initially identified, with 14 studies meeting the inclusion criteria, encompassing 999 subjects (739 in the OSAS group and 260 in the healthy group). Meta-analysis results indicated that the superficial capillary plexus (SCP) density in the fovea (MD=–2.05, 95%CI –3.75 to –0.35, P=0.02) and parafovea (MD=–1.56, 95%CI –2.44 to –0.68, P=0.000 5) was significantly lower in the OSAS group compared with the healthy group. In the mild to moderate OSAS group, SCP density was significantly lower in the fovea (MD=–2.41, 95%CI –4.32 to –0.49, P=0.01), parafovea (MD=–1.17, 95%CI –2.01 to –0.32, P=0.007), and perifovea (MD=–1.73, 95%CI –2.69 to –0.77, P=0.000 4) compared with the healthy group. In the severe OSAS group, SCP density in the perifovea (MD=–1.33, 95%CI –2.53 to –0.13, P=0.03) was significantly lower than that of the healthy group. SCP density in the whole area (MD=0.36, 95%CI 0.05 to 0.68, P=0.02) was significantly higher in the mild to moderate OSAS group compared with the severe OSAS group. In the deep capillary plexus (DCP) density, the OSAS group showed significantly lower densities in the whole area (MD=–2.16, 95%CI –3.51 to –0.81, P=0.002), fovea (MD=–2.38, 95%CI –4.38 to –0.37, P=0.02), and parafovea (MD=–2.33, 95%CI –3.93 to –0.73, P=0.004) compared with the healthy group. The mild to moderate OSAS group also showed significantly lower densities in the whole area (MD=–2.02, 95%CI –3.33 to –0.72, P=0.002) and parafovea (MD=–1.65, 95%CI –3.04 to –0.26, P=0.02) compared with the healthy group. The severe OSAS group had significantly lower DCP density in the whole area (MD=–2.26, 95%CI –3.85 to –0.66, P=0.006) and parafovea (MD=–1.47, 95%CI –2.31 to –0.62, P=0.000 7) compared with the healthy group. DCP density in the whole area (MD=0.54, 95%CI 0.02 to 1.07, P=0.04) was significantly higher in the mild to moderate OSAS group compared with the severe OSAS group. Regarding the retinal nerve fiber layer (RNFL) thickness, the inferior quadrant (MD=4.01, 95%CI 0.69 to 7.32, P=0.02) and temporal quadrant (MD=4.35, 95%CI 1.88 to 6.82, P=0.000 6) were significantly thicker in the mild to moderate OSAS group compared with the severe OSAS group. In terms of the foveal avascular zone (FAZ) area, the severe OSAS group showed a significantly larger FAZ area (MD=0.06, 95%CI 0.03 to 0.08, P<0.000 01) compared with the healthy group. Conclusion OCTA-related ocular biomarkers may be associated with the occurrence and progression of OSAS and have potential applications in the diagnosis and treatment of OSAS.

    Release date:2025-03-25 01:25 Export PDF Favorites Scan
  • Optical coherence tomography features of central exudative chorioretinopathy

    Objective lt;brgt;To investigate the morphological features of choroidal neovascularization (CNV) in central exudative chorioretinopathy (CEC) using optical coherence tomography(OCT). lt;brgt; lt;brgt;Methods lt;brgt;OCT and fundus fluorescein angiography (FFA) were performed in 41 cases (43 eyes) of CEC,and the course of CEC disease was from 1 week to 10 months. Twenty-seven of 43 eyes were also examined by indocyanine green angiography (ICGA). lt;brgt; lt;brgt;Results lt;brgt;OCT images revealed 5 kinds of morphological features of CEC: well-defined CNV(41.86 %),poorly-defined CNV(30.23 %),hemorrhagic pigment epithelium detachment (PED)(16.28 %), CNV companied with serous (6.98 %) or hemorrhagic neurosensory retina detachment (4.65 %). CNV mainly showed well-defined and poorly-defined CNV (72.09 %).In those eyes that could clear define the CNV boundary,there were 12 eyes on FFA examination and 20 eyes on ICGA examination which defined the boundary from retinal horizontal plane, while there were 23 eyes on OCT examination which defined the boundary from retinal vertical section. Classic CNV on FFA consistently presented with well-defined boundaries on OCT, whereas non-classic CNV had a variable cross-sectional appearance. lt;brgt; lt;brgt;Conclusions lt;brgt;The OCT morphological features of CNV in CEC is mainly well-defined CNV and poorly-defined CNV; OCT examination can precisely observe the retinal and choriocapillaries pathological anatomy of CEC from retinal vertical section, in making the CEC diagnosis as an important complementary examination of FFA and ICGA which observe the focus from retinal horizontal plane. lt;brgt; lt;brgt;(Chin J Ocul Fundus Dis, 2002, 18: 121-124)

    Release date:2016-09-02 06:01 Export PDF Favorites Scan
  • The pattern characteristics of optical coherence tomography in diabetic maculopathy

    Objective To verify the pattern characteristics of optical coherance tomography (OCT) images in diabetic maculopathy (DM). Methods OCT were performed in sixty cases of DM and 30 cases of normal control group,and in 54 cases of DM,fundus fluorescein angiography (FFA) was performed simutaneously.The results from 2 kinds of examinations were compared each other. Results The average retinal thickness at the central fovea was (314.54plusmn;154.13) mu;m in DM group.The macular edema in the cases of DM accounted to 57.1% on OCT examination. The rate of retinal swelling associated with cystoid macular edema (CME) was 38.5%,with retinal detachment (RD) 9.2%,and with both CME and RD was 16.9%Those with mormal macular thickness and mild macular edema primarily showed focal leakage in FFA exam,while those with moderate and severe macular edema showed diffuse leakage in FFA exam.The rate of CME was 28.6% presented in FFA and 58.9% in OCT examination (t= 3.39,Plt;0.05). Conclusion OCT images of DM reveal 3 kinds of morphological features:retinal welling,CME,and sensory retinals de tachment.OCT is superior to FFA in detecting CME. (Chin J Ocul Fundus Dis, 2001,17:184-186)

    Release date:2016-09-02 06:03 Export PDF Favorites Scan
  • 努力提高光相干断层扫描检查结果的认知水平提升检查的临床应用价值

    Release date:2016-09-02 05:52 Export PDF Favorites Scan
  • 黄斑裂孔手术治疗中内界膜的处理

    黄斑裂孔手术中内界膜(internal limiting membrane,ILM)剥除的有效性尚有许多争议。目前,多数研究者提倡进行ILM的剥除。因ILM的剥除提高了黄斑裂孔手术的解剖成功率,并使视力明显提高,且缩短了手术后俯卧位的时间;但在手术适应证的选择上还存在分歧。文献报道的资料由于标准不同,难以进行统计学方面比较。只有前瞻、随机、双盲、足够病例的临床试验,进一步加强临床追踪以及随着黄斑裂孔手术方式、技巧的不断改进完善,进一步验证ILM剥除的利弊,才能对其做出全面客观的评价。 (中华眼底病杂志,2003,19:201-268)

    Release date:2016-09-02 06:00 Export PDF Favorites Scan
  • Analysis of Flash Electroretinogram and Optical Coherence Tomography for Patients with Primary Retinitis Pigmentosa

    ObjectiveTo use flash electroretinogram (F-ERG) and optical coherence tomography (OCT) to examine patients with primary retinitis pigmentosa (RP), and analyze the specificity of the disease on F-ERG and OCT. MethodsThirty-seven patients (74 eyes) diagnosed with primary retinitis pigmentosa in the Department of Ophthalmology, West China Hospital between September 2013 to October 2014 and 38 normal volunteers (76 eyes) were included in this study. F-ERG and OCT examinations were performed on all the patients. Then, we analyzed the differences between the two groups of subjects. ResultsFor RP patients undergoing P-ERG examination with the dark adaptation of 0.01 ERG, the latency of b wave was (73.24±6.42) ms and the amplitude of b wave was (22.87±22.48) μV; when dark adaptation of 3.0 ERG was adopted, the latency of a wave was (24.57±6.30) ms, the amplitude of a wave was (35.45±25.54) μV, the latency of b wave was (48.19±8.18) ms, and the amplitude of b wave was (119.47±50.89) μV; with the light adaptation of 3.0 ERG, the latency of a wave was (21.01±4.86) ms, the amplitude of a wave was (12.59±13.43) μV, the latency of b wave was (38.43±5.00) ms, and the amplitude of b wave was (27.19±38.12) μV. For normal volunteers undergoing F-ERG examination with the dark adaptation of 0.01 ERG, the latency of b wave was (72.63±3.49) ms and the amplitude of b wave was (86.36±21.57) μV; when the dark adaptation was 3.0 ERG, the latency of a wave was (22.88±1.62) ms, the amplitude of a wave was (210.74±43.57) μV, the latency of b wave was (42.59±2.60) ms, and the amplitude of b wave was (398.29±62.42) μV; when the light adaptation of 3.0 ERG was adopted, the latency of a wave was (16.61±0.87) ms, the amplitude of a wave was (54.26±19.64) μV, the latency of b wave was (33.29±1.11) ms, and the amplitude of b wave was (176.98±63.44) μV. There were no significant differences between the two groups when dark adaptation ERG was 0.01 (P=0.48), but for other adaptations, there were significant differences in the latency and amplitude of a and b wave between the two groups (P<0.05). The results of OCT showed that the retinal thickness of the RP patients with a range of 1 mm diameter centered on macular center concave was (218.66±74.14) mm, 3 mm diameter was (275.03±47.85) mm, and 6 mm diameter was (247.37±46.44) mm. For normal volunteers, OCT showed that the retinal thickness with a 1 mm range centered on macular center concave was (250.38±15.79) mm, 3 mm was (323.64±17.26) mm, and 6 mm was (283.44±12.50) mm. The differences between the two groups were statistically significant for each range (P<0.01). ConclusionFor patients with RP, F-ERG shows latency delay and amplitude decrease for each response, while OCT displays a thinning thickness of macular fovea. Therefore, F-ERG and OCT can not only effectively evaluate the functions of macular and the surrounding retina, but can also be used as an effective method for the diagnosis of RP.

    Release date:2016-11-23 05:46 Export PDF Favorites Scan
  • Analysis of changes of visual acuity, multifocal electroretinogram and optical coherence tomogram before and after successful idiopathic macular hole surgery

    Objective To observe the changes of visual acuity、multifocal electroretinogram (mfERG) and optical coherence tomogram(OCT)before and after successful idiopathic macular hole (IMH) surgery, and evaluate the efficiency of the IMH surgery. Methods A total of 28 eyes of 28 patients with IMH who underwent vitrectomy during February 2001 and May 2002 in our hospital were collected. visual acuity, mfERG, and OCT were examined preoperatively and 1, 3, 6, and 12 months postoperatively, respectively. The results were analyzed statistically compared with 33 eyes in control group. Results (1) OCT showed that 27 eyes (96.43%) had anatomic closure of the macular hole 1 month after the surgery without recurrence in 12 months. Just 1 eye (3.57%) failed in the closure within 1 year. (2) The visual acuity was much higher in the eyes 1 year after surgery, especially within 6 months postoperatively, than that before the vitrectomy(P<0.01). (3) Before the operation, the mfERG topographies of IMH eyes seem like volcanoes becase the response densities of wave P1 of ring 1 and ring 2 were lower than control group while the other three rings kept in normal. The central peaks of mfERG topographies reappeared little by little during 1 year after the surgery, and the response densities of wave P1 of ring 1 and ring 2 were higher than before, which was still lower than the control group(P<0.05). (4) The thickness of neuroepithelial layer (NEL) of fovea measured by OCT of 27 eyes with anatomic closure was no longer varied and kept lower than control group throughout the follow-up time (P<0.05). (5) One year after the operation, there were positive correlations among visual acuity, mfERG and NEL(P<0.05). Conclusions Vitrectomy is useful for IMH, which could be evaluated by visual acuity mfERG and OCT efficiently. The three factors had consistency. (Chin J Ocul Fundus Dis,2004,20:221-225)

    Release date:2016-09-02 05:58 Export PDF Favorites Scan
  • Numerical Simulation of Heat Transfer in the Human Anterior Chamber at Different Corneal Temperatures

    A three-dimensional (3D) model of human anterior chamber is reconstructed to explore the effect of different corneal temperatures on the heat transfer in the chamber. Based on the optical coherence tomography imaging of the volunteers with normal anterior chamber, a 3D anterior chamber model was reconstructed by the method of UG parametric design. Numerical simulation of heat transfer and aqueous humor flow in the whole anterior chamber were analyzed by the finite volume methods at different corneal temperatures. The results showed that different corneal temperatures had obvious influence on the temperature distribution and the aqueous flow in the anterior chamber. The temperature distribution is linear and axial symmetrical around the pupillary axis. As the temperature difference increases, the symmetry becomes poorer. Aqueous floated along the warm side and sank along the cool side which forms a vortexing flow. Its velocity increased with the addition of temperature difference. Heat fluxes of cornea, lens andiris were mainly affected by the aqueous velocity. The higher the velocity, the bigger more absolute value of the above-mentioned heat fluxes became. It is practicable to perform the numerical simulation of anterior chamber by the optical coherence tomography imaging. The results are useful for studying the important effect of corneal temperature on the heat transfer and aqueous humor dynamics in the anterior chamber.

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