1. <div id="8sgz1"><ol id="8sgz1"></ol></div>

        <em id="8sgz1"><label id="8sgz1"></label></em>
      2. <em id="8sgz1"><label id="8sgz1"></label></em>
        <em id="8sgz1"></em>
        <div id="8sgz1"><ol id="8sgz1"><mark id="8sgz1"></mark></ol></div>

        <button id="8sgz1"></button>
        west china medical publishers
        Keyword
        • Title
        • Author
        • Keyword
        • Abstract
        Advance search
        Advance search

        Search

        find Keyword "Tomography" 366 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
        • 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
        • Comparison of confocal laser scanning colorful fundus imaging and color fundus photography for detection of diabetic retinopathy

          ObjectiveTo compare the imaging characteristics and detection of various types of lesions in diabetic retinopathy (DR) with colorful laser scanning fundus imaging (MSLI) and traditional color fundus photography (CFP).MethodsProspective case series observational study. A total of 38 eyes of 38 patients with DR diagnosed by clinical examination were included in the study. Among them, 21 were male and 17 were female; the mean age was 62.6±11.2 years; the average duration of diabetes was 14.3±7.5 years. All the patients were performed CFP, MSLI, frequency domain optical coherence tomography (SD-OCT), fluorescein angiography (FFA) examination. Using the Helielberg Spectralis HRA+OCT MSLI inspection, one scan simultaneously obtained 488 nm blue reflection (BR), 515 nm green light reflection (GR), 820 nm infrared light reflection (IR), and multicolor image (MC). The detection of traditional CFP and MC on microaneurysm (MA), hard exudation (HEX), cotton plaque (CWS), intraretinal hemorrhage (IRH), intraretinal microvascular abnormality (IRMA), venous bead (VB), venous ring (VL), macular edema (DME), macular anterior membrane (MEM) and laser photocoagulation (LB) were comparatively observed. The results of FFA examination were used as the diagnostic criteria for lesions. SD-OCT was used to determine the location and depth of lesions and the diagnostic reference for DME and MEM.ResultsThe numbers of eyes with MA (χ2=10.460), DME (χ2=4.006), MEM (χ2=4.444) was significantly higher in MC than that of traditional CFP. But the number of eyes with IRH (χ2=0.103), CWS (χ2=1.515), HEX (χ2=0.227), IRMA (χ2=0.051), VB (χ2=0.001), VL (χ2=0.149), VH (χ2=0.693) and LB (χ2=0.720) were not statistically significant between two methods (P>0.05). The imaging quality of MSLI mode is obviously better than that of traditional CFP. Among them, GR imaging shows the best structural changes of superficial retina in MA, CWS, HEX, MEM, etc. IR imaging shows clear depth in deep retina such as LB. DME was green on MC and the weak low-reflection dark area was visible on the IR image, which were consistent with the DME range indicated by the SD-OCT examination.ConclusionsCompared with the traditional CFP, the MSLI can clearly show the DR lesion. The number of checkouts is high on MA, DME and MEM by MC image.

          Release date:2018-07-23 04:02 Export PDF Favorites Scan
        • Changes of foveal avascular zone size and correlation between foveal avascular zone size and metamorphopsia before and after idiopathic macular epiretinal membrane surgery

          ObjectiveTo observe the changes of foveal avascular zone (FAZ) size before and after surgery in idiopathic macular epiretinal membrane (IMEM) eyes and analyze the correlation of FAZ with metamorphopsia.MethodsA retrospective case series study. From August 2016 to October 2017, 42 eyes of 38 patients affected with IMEM diagnosed in Central Theater Command General Hospital of Chinese People's Liberation Army were enrolled in this study. All the patients underwent a 25G pars plana vitrectomy (PPV) with IMEM removal and ininternal limiting membrane (ILM) peeling. The BCVA was measured using the international standard visual acuity chart, and the results were converted to the logMAR visual acuity. The severity of metamorphopsia was measured using M-charts. The FAZ areas were evaluated with OCT angiography in both the superficial and deep capillary plexus layers. The central macular thickness (CMT) were assessed with spectral-domain OCT before and after surgery. The logMAR BCVA was 0.61±0.21. The M-score was 0.66±0.38. The CMT of fovea was 337.71±57.63 μm. The FAZ areas in superficial and deep capillary plexus were 0.113±0.037 mm2 and 0.202±0.03 mm2, respectively. The differences in BCVA, M-score and FAZ area before and 1, 3, 6, 12 months after surgery were analyzed by ANOVA. The Spearman rank correlation analysis was performed to investigate the relationship between FAZ areas, visual acuity and metamorphopsia.ResultsAt 12 month after surgery, the FAZ areas in superficial and deep capillary plexus were 0.146±0.021 mm2 and 0.240±0.019 mm2, respectively. Compared with baseline, the the FAZ areas in superficial and deep capillary plexus after surgery significantly increased (F=8.484, 14.346; P<0.001,<0.001). The postoperative logMAR BCVA 0.47±0.19, M-score 0.12±0.22 and CMT 270.60±33.27 μm were significantly improved compared with baseline (F=5.044, 17.763, 13.545; P=0.001,<0.001,<0.001). The preoperative FAZ area in superficial capillary plexus correlated negatively with preoperative M-score (r=-0.816, P<0.001); the preoperative FAZ area in deep capillary plexus correlated negatively with preoperative BCVA and M-score (r=-0.422, -0.882; P=0.005,<0.001). The postoperative FAZ area in superficial capillary plexus correlated negatively with preoperative and postoperative M-score (r=-0.791,-0.716; P<0.001,<0.001). The postoperative FAZ area in deep capillary plexus correlated negatively with BCVA and preoperative and postoperative M-score (r=-0.343, -0.330, -0.732, -0.694; P=0.026, 0.033,<0.001,<0.001).ConclusionsPPV with ILM peeling can effectively restore the FAZ areas in superficial and deep capillary plexus, improve the visual acuity and metamorphopsia in patients with IMEM. Both superficial and deep plexus FAZ areas correlated negatively with metamorphopsia, and deep plexus FAZ area also correlated negatively with BCVA.

          Release date:2020-04-18 07:44 Export PDF Favorites Scan
        • Dominant distribution and pathological basis of thin layer 16-slice spiral CT signs of coal workers’ pneumoconiosis

          Objective To clarify the thin-layer 16-slice spiral CT features of coal worker’s pneumoconiosis and the superior distribution of comorbidities in their staging and lobes and lung field anatomy. Methods Sixty-six patients with coal worker's pneumoconiosis diagnosed by the pneumoconiosis diagnosis and identification group from October 2014 to March 2015 were enrolled. All patients underwent 16-slice spiral CT and thin-layer CT reconstruction with a thickness of 1.5 mm. The thin-slice CT signs and comorbidities of coal workers’ pneumoconiosis were observed, and the superior distribution of CT signs in patients at different stage and different lobes and lung field anatomy were evaluated. Results There were 16 cases of irregular small nodules in the lungs, 22 cases of large shadow fusion, 18 cases of intraocular shadow calcification, 41 cases of emphysema, 21 cases of pulmonary bullae, 21 cases of pulmonary hypertension, and 31 cases of enlarged lymph nodes in the mediastinum and calcified. The above signs were mostly distributed in stage Ⅲ pneumoconiosis (P<0.05). There were 32 cases of regular small nodules, which were mostly distributed in stage Ⅰ pneumoconiosis. In the 16 cases of irregular small nodules, the advantage was distributed in the middle and outer lobes of the double lungs. In the 22 cases of large shadow fusion, the advantage was distributed in the upper and lower lobe of the lungs. In the 16 cases of tuberculosis, the advantage was distributed in the upper lobe of the lungs. In the 21 cases of bullous bullae, the advantage was distributed in the upper lobe of the two lungs, mostly in the right upper lung. Conclusion The thin 16-slice spiral CT signs of coal worker’s pneumoconiosis can reflect the pathological changes, and have a certain correlation with the stage of pneumoconiosis, and have obvious characteristics in the anatomical distribution of lung and lung fields.

          Release date:2019-01-23 01:20 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
        • 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
        • Optical coherence tomography: a new era of ocular-fundus imageologic

          Optical coherence tomography (OCT) has developed from time-doma in into Fourier-domain OCT (FD-OCT) which indicates clearer details and higher resolution of images. FD-OCT can indicate the structure and pathological changes of each retinal layer, and reveal the retinal external limiting membranes and changes of inner- and outer-segment of visual cells by 3D solid reconstruction. FD-OCT not only provide detailed information of the images for the clinical diagnosis, but also help us investigting the characteristics and pthological mechanisms of ocular fundus diseases, which lead us to a new era of technology of observation on ocualr fundus diseases. In the application, we should pay attention to the significance of different colors of OCT images, and focus on the cohenrence of the position in the image acquistion during the follow-up period. Dynamic observation on the lesions by FD-OCT and aggregated anaylsis of resutls of several imageological examination would be the development direction of imageological examination of ocular fundus diseases.

          Release date:2016-09-02 05:42 Export PDF Favorites Scan
        • The progress of the study of lipid globules in the retina and choroid

          Lipid globules in retina and choroid are new definitions based on pathology and high-resolution optical coherence tomography (OCT). OCT examination shows that the lipid globules are low reflective circular cavities in the choroid and retina, without strong reflective boundaries around them, followed by a characteristic superreflective tail. It occurs in healthy human eyes and in age-related macular degeneration characterized by retinal pigment epithelium (RPE) atrophy. Its characteristic superreflective tail is the key to distinguishing it from other diseases. At present, the understanding of lipid globules is still in the initial stage. Although lipid globules can be observed in healthy human eyes, a certain prevalence rate indicates that they are associated with choroidal hypoperfusion and RPE atrophy. In the future, larger randomized controlled trials and longer follow-up time are needed to explore its pathogenesis, pathological characteristics and treatment prognosis.

          Release date:2024-04-11 09:03 Export PDF Favorites Scan
        • The morphological characteristics and complications treatment of dome-shaped macula in high myopia

          Dome-shaped macula (DSM) of high myopia has been described as an inward convexity or bulge of the macular within the concavity of the posterior staphyloma in highly myopic eyes, with the bulge height over than 50 μm, which can be observed by optical coherence tomography. There are three patterns of DSM, including the typical round dome, the horizontally oriented oval-shaped dome and the vertically oriented oval-shaped dome. The pathogenesis of DSM development remains unclear, several hypotheses have been suggested, such as localized choroidal thickening in the macular area, relatively localized thickness variation of the sclera under the macula, resistance to deformation of sclera staphyloma, ocular hypotony and tangential vitreoretinal traction. Vision-threatening macular complications of DSM including serous retinal detachment, choroidal neovascularization, foveoschisis and retinal pigment epithelial atrophy. Clinically, asymptomatic patients with DSM mainly take regular follow-up observation. Appears serous retinal detachment and significant visual impairment, treatment with half-dose photodynamic therapy, supplementary of laser photocoagulation or oral spironolactone may have a beneficial effect. However, more large clinical studies are required to confirm the exact efficacy of these treatments.

          Release date: Export PDF Favorites Scan
        37 pages Previous 1 2 3 ... 37 Next

        Format

        Content

          1. <div id="8sgz1"><ol id="8sgz1"></ol></div>

            <em id="8sgz1"><label id="8sgz1"></label></em>
          2. <em id="8sgz1"><label id="8sgz1"></label></em>
            <em id="8sgz1"></em>
            <div id="8sgz1"><ol id="8sgz1"><mark id="8sgz1"></mark></ol></div>

            <button id="8sgz1"></button>
            欧美人与性动交α欧美精品