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find Keyword "体层摄影术,光学相干" 203 results
  • Clinical application and new progress of optical coherence tomography in detecting lamina cribrosa structure

    The lamina cribrosa (LC) is a complicated collagenous meshwork of trabeculae and laminar pores contain capillaries, nerves and neurogliocytes, which provides structural and nutrient support to the retinal ganglion cell axons as they exit the eye. The intraocular pressure causes direct damage or deformation and remodeling of LC, leads to axoplaxmic transport and blood supply disturbance. The preponderance of evidence suggests that LC is the principal site of glaucomatous damage. The development of optic coherence tomography (OCT) technology has improved the imaging quality of deep structures of the optic nerve head and makes it possible to detect LC. The quantitative research indexes of LC structure include LC depth, laminar curvature, laminar thickness, prelaminar tissue, laminar pore, laminar defect and hemodynamics. To improve the understanding of LC structure, explore the characteristics of LC and understand the biomechanical and hemodynamic pathogenesis of glaucoma, which would be contribute to the application of big data research in the diagnosis and treatment of glaucoma.

    Release date:2021-03-19 07:10 Export PDF Favorites Scan
  • 手术中光相干断层扫描辅助治疗视盘小凹1例

    Release date:2024-09-20 10:48 Export PDF Favorites Scan
  • Research progress of optical coherence tomography combined with microperimetry in diabetic macular edema

    Diabetic macular edema is the major cause of vision impairment in patients with non-proliferative diabetic retinopathy. Thickness and pathological alterations in each retina layer of diabetic macular edema (DME) patients can be performed by optical coherence tomography (OCT) device. And retinal light sensitivity at specific retinal point and fixation state can be detected by microperimetry qualitatively and quantitatively. Moreover, OCT can discover pathological anatomical changes in the retina of DME patients, thus facilitating the interpretation of the structure-function relationship in DME with combination of microperimetry results. At present, there are various therapies for DME patients, and the primary method in evaluating therapeutic efficacy is to compare the pathological changes in the retina before and after treatment by OCT. Besides, microperimetry can provide information in visual function restoration. The combined application of OCT and microperimetry has broad prospects in the diagnosis and treatment of DME patients.

    Release date:2018-07-23 04:02 Export PDF Favorites Scan
  • Scleral thickness in high myopic eyes

    Thinning and atrophy of sclerotic tissues play an important role in the development of high myopia. High myopic eyes had the thickest sclera at the posterior pole and the thinnest sclera at the equator. Most clinical studies found that scleral thickness was negatively correlative with the axial length. Patients complicated with posterior staphyloma had even thinner sclera, and its height was negatively related with the scleral thickness. At present, the main measurement methods for scleral thickness of high myopic eyes include histological measurement, enhanced depth imaging optical coherence tomography (OCT), and swept-source OCT. Following the development of OCT technique, it gradually becomes feasible to carry out studies on sclera thickness in mildly and moderately myopic populations, which is helpful to illuminate the mechanism of action of sclera on the onset and progression of high myopia.

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  • Research progress of optical coherence tomography biomarkers in macular edema secondary to retinal vein occlusion

    Retinal vein occlusion (RVO) is one of the most common retinal vascular diseases causing blindness, macular edema (ME) is often secondary to it, which causes serious visual impairment to patients. Imaging biomarkers in the changes of retina and choroid of ME secondary to RVO (RVO-ME) have important clinical value in the evaluation of condition, curative effect and visual acuity prediction of patients with RVO-ME. Among them, the disorganization of the retinal inner layers, the integrity of external limiting membrane and ellipsoid zone, and the change of central macular thickness are reliable indexes to evaluate the prognosis of visual acuity; hyperreflective foci, subretinal fluid and intraretinal fluid can be used as important parameters to reflect the level of inflammation; prominent middle limiting membrane and paracentral acute middle maculopathy are the objective basis for judging the degree of retinal ischemia; the changes of choroidal vascular index and choroidal thickness also have potential advantages in evaluating the progress of the disease. Accurately grasp the characteristics of biological markers of RVO-ME related optical coherence tomography is conducive to its reasonable and accurate use in the clinical diagnosis and treatment of RVO-ME, and helpful to further explore the pathogenesis of the disease.

    Release date:2024-06-18 11:04 Export PDF Favorites Scan
  • Image characteristics of optical coherence tomography vascular imaging on polypoid choroidal vascular disease after anti-vascular endothelial growth factor drug treatment

    ObjectiveTo observe the optical coherence tomography angiography (OCTA) image characteristics of polypoid choroidal vascular disease (PCV) after intravitreal injection of anti-vascular endothelial growth factor drugs, and to discuss its significance in the diagnosis and follow-up of PCV.MethodsA retrospective case study. From August 2018 to January 2020, 22 eyes of 22 patients with PCV diagnosed in the ophthalmological examination of Affiliated Hospital of Weifang Medical University were included in the study. Among them, there were 10 males with 10 eyes and 12 females with 12 eyes; the average age was 67.75±9.53 years. Best corrected visual acuity (BCVA), OCTA, and indocyanine green angiography (ICGA) were performed. All the affected eyes were injected vitreously with 10 mg/ml Conbercept 0.05 ml (including Conbercept 0.5 mg) once a month for 3 consecutive months.Tthe macular area of 3 mm×3 mm and 6 mm×6 mm with an OCTA instrument was scanned, and the foveal retinal thickness (CRT) was measured, the area of abnormal branch blood vessels (BVN). pigment epithelial detachment before and 12 months after treatment (PED) height, foveal choroid thickness (SFCT) were performed. The diagnosis rate of PCV by OCTA was observed, as well as the changes of various indicators of BCVA and OCTA. Before and after treatment, BCVA and CRT were compared by paired t test; BVN area, PED height, and SFCT were compared by variance analysis. The changes in imaging characteristics of OCTA before and after treatment were analyzed.ResultsAmong the 22 eyes, 8 eyes were BVN; 5 eyes were polypoid lesions (polyps); 5 eyes were BVN combined with polyps; 3 eyes were not found with BVN and polyps; 1 eye with small vascular network structure, this eye was ICGA Appears as strong nodular fluorescence (polyps). The detection rate of PCV by OCTA was 86.36% (19/22). Twelve months after treatment, BVN was significantly reduced or disappeared in 16 eyes (72.72%, 16/22); polyps disappeared in 17 eyes (77.27%, 17/22). Compared with before treatment, 12 months after treatment, BCVA increased (t=3.071), CRT decreased (t=2.440), the difference was statistically significant (P<0.05); the average BVN area, PED height, and SFCT decreased. The difference in average BVN area and PED height was statistically significant (F=2.805, 3.916; P<0.05), and the difference in SFCT was not statistically significant (F=0.047, P>0.05).ConclusionsThe detection rate of PCV by OCTA is 86.36%. After PCV anti-vascular endothelial growth factor drug treatment, BVN area decrease and polyps subside. OCTA is an effective means for PCV diagnosis and follow-up after anti-VEGF drug treatment.

    Release date:2021-07-21 02:11 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
  • Optical coherence tomography angiography imaging features of choroidal neovascularization with different activity in age-related macular degeneration

    Objective To observe the OCT angiography imaging features of choroidal neovascularization (CNV) with different activity in age-related macular degeneration (AMD). Methods A retrospective case analysis. Forty-two eyes of 33 patients (21 males and 12 females, aged 65.3±8.61 years) who were diagnosed with AMD by multi-mode fundus imaging examination at the Ophthalmology Department of Yunnan Second People's Hospital during January 2017 and October 2018 were enrolled in this study. All patients underwent BCVA, slit-lamp biomicroscopy, indirect ophthalmoscopy, fundus colorized photography, FAF, FFA and OCT examinations. The patients were divided into active CNV (27 eyes of 19 patients) and inactive CNV (15 eyes of 14 patients) by comprehensive analysis of fundus imaging characteristics and treatment process. The imaging features of OCTA in the two groups were compared. The number of eyes of each active or inactive indicator in the active CNV group and the inactive CNV group was calculated, and the composition ratio of each group of the indicators was subjected to the χ2 test. Results Among the 27 eyes of active CNV, 22 eyes (81.5%) of OCTA showed abundant small capillary branching structure, while 13 eyes (13.3%) of 15 eyes of inactive CNV showed more coarse blood vessel. Among the 27 eyes of active CNV, 26 eyes (96.3%) of OCTA showed that the marginal vascular end points of CNV lesions were "arcaded" or "ring", while 12 eyes (80.0%) of 15 eyes of inactive CNV showed the presence of isolated branches of peripheral vessels. Among the 27 eyes with active CNV lesions, there were no large feeder vessels inside the lesions, and 8 (53.3%) of the 15 inactive CNV lesions showed feeder vessels in the center of the lesion. Among the 27 eyes with active lesions, 23 eyes (85.2%) of OCTA showed a low-reflection "halo" around the CNV lesion, and no low-reflection "halo" structure was observed in the 5 eyes of the inactive CNV lesion. The statistical results showed that there were abundant small blood vessel branches (χ2=22.759, P=0.000), annular anastomosis around the lesion (χ2=31.704, P=0.000), low-reflection halo (χ2=32.327, P=0.000), and large nourishing blood vessels (χ2=26.063, P=0.000), dilated choroidal vessels (χ2=32.912, P=0.000). All the above indicators were statistically different between the two groups. Conclusion The abundant small vessel branches in OCTA, the surrounding anastomosis in a ring structure and the low reflex halo around the lesion are markers of active CNV, while the large feeding vessels and dilated choroidal vessels are indicators of inactive CNV.

    Release date:2019-01-19 09:03 Export PDF Favorites Scan
  • Optical coherence tomography angiography characteristics of choroidal neovascularizaiton in eyes with flat irregular pigment epithelial detachments

    ObjectiveTo assess the occurrence of CNV in patients presenting with flat irregular pigment epithelial detachments (FIPED). MethodsForty-five patients (49 eyes) with FIPED on OCT were enrolled in this retrospective study. There were 25 males (28 eyes) and 20 females (21 eyes). The mean age was 61.022±9.292 years. FFA, ICGA, spectral domain OCT and OCT angiography (OCTA) were performed in all patients during the same period. The FIPED was defined as an irregular elevation of the RPE allowing distinct visualization of Bruch’s membrane on OCT B-scan. The abnormal vascular signals from the deep retinal layer to the choroid layer on OCTA was defined as CNV. The CNV was classified into a type 1 CNV and a type 2 CNV according to the OCT characteristics. The CNV was classified into a typical and occult CNV according to the characteristics of the FFA image. Of all 49 eyes, fundus angiography revealed 18 eyes (36.7%) with CNV, and 31 eyes (63.3%) with no characteristic signs of CNV. FFA examination found that CNV in 8 eyes (classic CNV in 1 eyes, occult CNV in 7 eyes), which confirmed by OCT were type 1 CNV; transmitted fluorescence in 41 eyes. ICGA examination showed that CNV-like hyperfluorescence spots in 18 eyes, suspicious hyperfluorescence spots in late stage in 20 eyes, and choroidal high permeability in 11 eyes, respectively; and 18 CNV eyes were confirmed to be type 1 CNV by OCT. To compare the detection of CNV by OCTA and fundus angiography. ResultsOf the 49 eyes with FIPED, OCTA detected 36 eyes (73.5%) of type 1 CNV, and full or partial strong reflex signals were seen in FIPED; 13 eyes (26.5%) were not associated with CNV, and some strong reflection signals were found in FIPED in 9 eyes, 4 eyes with weak reflection signal. The FFA was examined for 1, 7 eyes of the classic and occult CNV, which confirmed to be type 1 CNV by OCTA. Among the 18 eyes with CNV which detected by ICGA, OCTA also found type 1 CNV. Among the 20 eyes with ICGA’s late suspicious strong fluorescent spots, OCTA showed 17 eyes of type 1 CNV; in 11 eyes with high choroidal permeability, OCTA showed type 1 CNV in 1 eye. Among the 36 eyes with CNV which detected by OCT, there were SRD in 32 eyes, no SRD in 2 eyes and retinal interlamellar cavities in 2 eyes. ConclusionOCTA can detect 73.5% of FIPED eyes with CNV. Compared with traditional fundus angiography, OCTA has a higher detection rate of CNV under FIPED. The FIPED of the internal strong reflection signal has a certain diagnostic value for the type 1 CNV.

    Release date:2019-01-19 09:03 Export PDF Favorites Scan
  • The macular vascular density and the area of foveal avascular zone in the follow eyes of monocular retinal vein occlusion patients

    ObjectiveTo observe the macular vascular density and the area of foveal avascular zone (FAZ) in the follow eyes of monocular retinal vein occlusion (RVO) patients.MethodsRetrospective case-control study. From May to November 2018, 78 follow eyes of 78 monocular RVO patients who were clinically diagnosed in Changsha Aier Eye Hospital were included in the study. Among them, 44 were male and 34 were female. The average age was 53.17±10.12 years. There were 42 patients with central retinal vein occlusion (CRVO group) and 36 patients with branch retinal vein occlusion (BRVO group). Forty-two eyes of 33 gender and age matched healthy volunteers were selected as the control group. Among them, 17 were male (22 eyes) and 16 were female (20 eyes), with the mean age of 53.48±10.84 years. OCT angiography was performed on all eyes in CRVO group, BRVO group and control group. The scanning region in the macular area was 6 mm×6 mm. Macular vascular density and FAZ area in the superficial and deep retinal capillary plexi were measured.ResultsThe mean overall vascular density measured in the entire scan was lower in the CRVO group (t=-4.26, -4.93) and BRVO group (t=-4.79, -4.74) compared with the control group in both the superficial and deep capillary plexus (P<0.05). The reduce degree of vascular density in the deep capillary plexus (CRVO group:5.51%, BRVO group:4.58%) was higher than that in the superficial plexus (CRVO group:4.13%, BRVO group:3.50%). In the CRVO group, the FAZ area decreased compared with the control group (t=-3.43, P<0.05). There was no statistically significant difference in the area of FAZ between the BRVO group and the control group (t=-0.10, P>0.05).ConclusionsThe macular vascular density in the follow eyes of monocular RVO patients is lower than that of normal healthy eyes. The reduce degree of vascular density in the deep capillary plexus is higher than that in the superficial plexus. Compared with normal healthy eyes, the FAZ area in the follow eyes of monocular CRVO patients decreased, while it did not change significantly in the follow eyes of monocular BRVO patients.

    Release date:2020-05-19 02:20 Export PDF Favorites Scan
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