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find Keyword "Tomography" 365 results
  • Reproducibility of macular ganglion cell-inner plexiform layer measurements using spectral-domain optical coherence tomography

    ObjectiveTo evaluate the repeatability and reproducibility of macular ganglion cell-inner plexiform layer (GCIPL) thickness measurement using spectral-domain optical coherence tomography (Cirrus HD-OCT). MethodOne hundred and eight eyes of 54 normal subjects (26 males and 28 females) between 19 and 75 years of age were included. Each eye underwent macular scanning using Cirrus HD-OCT Macular Cube 512×128 protocol by two operators. Three scans of each eye were obtained by each operator. For the right eye of each subject, three extra scans were obtained using Macular Cube 200×200 protocol by one operator. The average, minimum, superotemporal, superior, superonasal, inferonasal, inferior, and inferotemporal GCIPL thickness was analyzed and the repeatability of GCIPL thickness measurement was evaluated with intra-operator, inter-operator, intra-protocol, and inter-protocol intraclass correlation coefficients (ICC). Ten extra scans were obtained from the left eyes of 10 randomly selected subjects for reproducibility assessment with coefficients of variation (CV). ResultsThe intra-operator ICC of macular GCIPL measurement using Macular Cube 512×128 protocol by two operators were 0.959-0.995 and 0.954-0.997, respectively; and the inter-operator ICC were 0.944-0.993. All intra-and inter-operator ICC were > 0.800 with the highest and lowest records of the average and minimum GCIPL thickness, respectively. The intra-protocol ICC of Macular Cube 512×128 protocol and Macular Cube 200×200 protocol were 0.986-0.996 and 0.927-0.997, respectively; and the inter-protocol ICC were 0.966-0.994. All intra-and inter-protocol ICC were > 0.800. CV of GCIPL thickness measurement using Macular Cube 512×128 protocol were (0.70±0.31)%-(1.35±0.86)%. ConclusionCirrus HD-OCT can measure macular GCIPL thickness in normal eyes with excellent repeatability and reproducibility.

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  • The relationship between the sizes of idiopathic macular hole and the healing types of fovea photoreceptor layer after vitrectomy

    Objective To observe the relationship between the size of idiopathic macular hole (IMH) and the healing types of postoperative photoreceptor layer after vitrectomy. Methods This prospective uncontrolled study included 33 eyes of 31 consecutive patients who underwent vitrectomy for IMH. There were 9 males (9 eyes) and 22 females (22 eyes), with the mean age of (58.16±9.10) years. The mean duration of symptoms was (4.97±5.97) months. The best corrected visual acuity (BCVA) and optical coherence tomography (OCT) were measured for all patients. BCVA was measured with international standard visual acuity chart and then converted to logarithm of the minimum angle of resolution (logMAR). The mean logMAR BCVA was 1.07± 0.38. The mean intraocular pressure was (14.05±0.54) mmHg (1 mmHg=0.133 kPa). The minimum size of the macular hole (MIN), the base diameter of the macular hole (BASE), the average width of the macular hole (AWMH) and the average height of the macular hole (AHMH) were (465.19±232.84), (943.63±389.26), (704.72±292.64), (443.84±72.47) μm, respectively. According to the MIN value, the hole size were divided into small, medium and large group which had 9 eyes, 15 eyes, 9 eyes, respectively. According to the postoperative OCT characteristics, the healing types of the photoreceptor layer were divided into 0 - Ⅳ types. All patients underwent pars plana vitrectomy (25G or 27G standard three-incision) with internal limiting membrane peeling with tamponade agents. The mean follow-up was (326.42±157.17) days. The first postoperative OCT characteristics were defined as the early period. The therapy results were evaluated according to the last follow-up time point. BCVA and intraocular pressure before and after operation were compared by paired t test. The postoperative BCVA were compared with preoperative BCVA, MIN, AWMH, AHMH and follow-up using Pearson correlation analysis. Results At the last follow-up, the LogMAR BCVA was 1.52 - 1.40 in 3 eyes, 1.30 - 0.52 in 22 eyes and 0.40 - −0.07 in 8 eyes. Compared with preoperative that, the difference was statistically significant (t=−6.023, P<0.001). The photoreceptor healing was type 0 in 10 eyes (30.3%), type Ⅰ in 4 eyes (12.1%), typeⅡ in 10 eyes (30.3%), type Ⅲ in 9 eyes (27.3%) at the early postoperative period. The photoreceptor healing was type 0 in 5 eyes (15.2%), type Ⅰ in 5 eyes (15.2%), type Ⅲ in 12 eyes (36.4 %), type Ⅳ in 11 eyes (33.3%) at the last follow-up. The preoperative size of IMH was negatively correlated to the photoreceptor healing types at early postoperative period (r=−0.590, P<0.01) and the last follow-up (r=−0.768, P<0.01), respectively. The correlation analysis showed that the postoperative BCVA associated with the preoperative BCVA, the stage of the macular hole, the size of the macular hole, MIN, BASE, AWMH, AHMH, the healing types of photoreceptor layer of the early and the last follow-up after surgery (r=0.500, 0.370, 0.470, 0.435, 0.533、0.505, 0.462, −0.442, −0.656, P<0.05). There was no correlation between age, visual decreasing times and follow-up times (r=0.285, 0.234, −0.310, P>0.05). Conclusion The preoperative sizes of IMH were associated with the postoperative healing types of photoreceptor layer.

    Release date:2018-03-16 02:36 Export PDF Favorites Scan
  • Correlation between macular blood flow density, structure and age in normal eyes

    ObjectiveTo observe the changes of blood flow density in the macular area of normal eyes, and to analyze its correlation with age. MethodsA cross-sectional study. Two hundred and fifty normal healthy subjects (125 males and 125 females, aged 44.76±14.77) in routine ophthalmologic examination at the Department of Ophtalmology of Guangdong Provincial People’s Hospital during June 2017 to June 2018 were enrolled. Among them, 20 to 29, 30 to 39, 40 to 49, 50 to 59, and ≥ 60 years old were 50 subjects (50 eyes) in each. BCVA, slit lamp microscope, indirect ophthalmoscope, OCT angiography (OCTA) examinations were conducted for all eyes. The subjects were examined by both eyes, and the data of 1 eye was selected by EXCEL to generate random numbers, including 126 right eyes and 124 left eyes. The range of 6 mm × 6 mm in the macular area was scanned using a frequency domain OCTA instrument. The software automatically divides it into three concentric circles centered on the macular fovea, which were foveal area with a diameter of 1 mm, parafoveal area of 1 to 3 mm, and foveal peripheral area of 3 to 6 mm. The blood flow density of superficial capillary vessel, deep capillary vessel and foveal avascular area (FAZ) within a 300 μm width (FD-300), FAZ area, perimeter (PERIM), non-circularity index, center retinal thickness (CRT) were measured. The relationship between the blood flow density in macula, CRT, FAZ and age was analyzed by Pearson correlation analysis. ResultsThe mean blood flow density of superficial capillary vessel and deep capillary vessel were (51.61±2.54)% and (54.04±5.46)%, respectively. The average FD-300, CRT, PERIM and non-circularity index were (285.55±12.13) μm, (2.150±0.367) mm, 1.10±0.04, respectively. The relevance of the results showed that the age was negatively correlated with the blood flow density of whole area (r=−0.335, −0.279; P<0.01), parafoveal area (r=−0.255, −0.368; P<0.01), foveal peripheral area (r=−0.330, −0.269; P<0.01) in superficial capillary vessel and deep capillary vessel as well as FD-300 (r=−0.311, P<0.01), but not correlated with the blood flow density of foveal area (r=−0.071, −0.118; P=0.264, 0.064). There was no relationship between the age and the FAZ area, PERIM, non-circularity index (r=−0.070, −0.055, 0.074; P=0.267, 0.385, 0.142). The age was negatively correlated with the average CRT (r=−0.217, P<0.01), but not correlated with the CRT in foveal area (r=0.115, P=0.068). The CRT was positively correlated with the blood flow density of superficial capillary vessel and deep capillary vessel in foveal area (r=0.715, 0.653; P<0.01), but negatively correlated with the FAZ area (r=−0.669, P<0.01). ConclusionThe capillary blood flow density of macular area in the normal eyes decreases with age.

    Release date:2019-01-19 09:03 Export PDF Favorites Scan
  • Image features of spectraldomain optical coherence tomography of high myopia with retinoschisis

      Objective To observe the image features of high myopia with retinoschisis by spectraldomain optical coherence tomography (SD-OCT). Methods The clinical data of eight patients (eight eyes) of high myopia with retinoschisis were retrospective analyzed. All patients were diagnosed by SD-OCT (Topcon 3D-OCT 1000), had no macular holes and underwent vitrectomy including internal limiting membrane (ILM) peeling and gas tamponade. All patients also underwent visual acuity, refraction, premirror fundus examination and A/B mode ultrasound examination. Visual acuity and SD-OCT were followed up at one, three and six months after surgery. Before surgery, premirror fundus examination revealed shallow foveal detachment in 3/8 eyes, posterior scleral staphyloma in 7/8 eyes. SD-OCT showed concave arc stripes in 7/8 eyes, and outer retinoschisis in 8/8 eyes, middle or inner retinoschisis in 5/8 eyes and foveal detachment in 5/8 eyes. Results Six months after surgery, posterior retinoschisis disappeared in six eyes, foveal detachment still presented in one eye and parafoveal hole occurred in one eye. The corrected visual acuity improved from the 0.15 to 0.8 in one eye which had a restored continuous inner segment/outer segmen (IS/OS) line by SD-OCT. The corrected visual acuity improved from 0.01 to 0.1 in one eye, from 0.05 to 0.15 in one eye, not changed in five eyes. There was no continuous IS/OS line in those patients by SD-OCT. Conclusions SD-OCT shows a variety of morphological features of myopic retinoschisis which could be cured anatomically and functionally by vitrectomy combined ILM peeling. The continuity of IS/OS layer from SD-OCT could help to interpret the vision recovery after the operation.

    Release date:2016-09-02 05:37 Export PDF Favorites Scan
  • The status in the application of optical coherence tomography angiography in noninfectious uveitis

    Noninfectious uveitis refers to a category of inflammatory diseases involving the uvea, vitreous, optic disk and retina, with the exception of infectious factors or masquerade syndrome. These kind of blinding diseases are frequently recurrent, and the diagnosis and follow-up require fundus imaging techniques. OCT angiography (OCTA) is a rapid, noninvasive and quantifiable blood flow imaging modality that provides a depiction of the microvasculature morphology of the retinal and choroidal through different segmentation and detects the abnormal blood perfusion as well as the neovascularization. OCTA plays an important role in the diagnosis, assessment and follow-up for anterior uveitis, posterior uveitis and pan-uveitis such as Vogt-Koyanagi-Harada disease, Behçet’s disease, ocular sarcoidosis, birdshot chorioretinopathy, serpiginous choroiditis, multifocal choroiditis, punctate inner choroidopathy, acute zonal occult outer retinopathy, acute posterior multifocal placoid pigment epitheliopathy, multiple evanescent white dot syndrome, and also provides clue about their pathophysiologic mechanisms.

    Release date:2019-07-16 05:35 Export PDF Favorites Scan
  • Clinical observation of persistent submacular fluid after scleral buckling surgery

    ObjectiveTo observe the occurrence and evolution of persistent submacular fluid (SMF) after scleral buckling surgery (SB) in rhegmatogenous retinal detachment, and then to study the related factors of persistent SMF and the effect of persistent SMF on visual outcome. MethodsNinety eyes of 89 patients with rhegmatogenous retinal detachment which had been performed SB were included in this study. Best corrected visual acuity (BCVA), intraocular pressure, slit-lamp microscopy, three mirror contact lens, indirect ophthalmoscopy and B-scan ultrasonography were measured for all patients. There were 21 eyes with atrophic holes while 42 eyes with horse-shoe tears, 22 eyes with old retinal detachment while 68 new suffered eyes. Thirty-two eyes underwent scleral encircling surgery (SE) and 58 eyes underwent segmental scleral buckling surgery (SSB). The patients were divided into SMF group and non-SMF (NSMF) group according to the results of optical coherence tomography (OCT) at 1 month postoperatively. Thorough ophthalmologic examinations were performd at 1, 3, 6 and 12 months after surgery to the patients, further observations were continued to carry out unless the abnormality had resolved for at least 6 months. ResultsPatients who underwent SE (20 eyes, 62.5%) had a higher incidence of persistent SMF at 1 month after surgery than those who underwent SSB (23 eyes, 39.7%), the difference was significant (χ2=5.024, P < 0.05). Persistent SMF was more frequent in eyes with atrophic holes (66.7%) than that with horseshoe tears (38.1%), the difference was significant (χ2=4.582, P < 0.05). Persistent SMF was found in 72.7% old retinal detachment eyes and in 39.7% new suffered eyes, showed a striking differences (χ2=7.264, P < 0.01). There was no significant difference in BCVA among SE and SSB groups at every time point (t=0.659, 0.699, 1.108, 1.037, 1.902; P > 0.05). The SMF group have a similar BCVA with NSMF group 1 and 3 months after surgery (t=1.812, 1.957; P > 0.05), whereas the SMF group showed worse BCVA than NSMF group from since 6 months after surgery (t=2.324, 2.147, 2.184; P < 0.05). ConclusionsPersistent SMF is more frequent after SE than SSB, the type of retinal breaks and old retinal detachment may be the potential influencing factors. Persistent SMF after SB may affect the final visual outcome.

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  • Application of Fluorine-18 Fluorodeoxyglucose Positron Emission Tomography in Patients with Pulmonary Tuberculosis

    Objective To assess the value of fluorine-18 fluorodeoxyglucose (18 F-FDG) positron emission tomography (PET) in patients with pulmonary tuberculosis. Methods Fifty-three patients with pulmonary tuberculosis were imaged with 18SF-FDG-PET. 18F-FDG-PET data were analyzed retrospectively with visual method and semiquantitative method. When pulmonary tuberculosis with abnormal 18F-FDG uptake appeared in PET scans confirmed by visual method, their maximum standard uptake value (SUVmax), mean standard uptake value (SUVmean) and standard uptake value of normal lung (SUVlung) were measured using semiquantitative method. Results Thirty-six pulmonary tuberculous nodules could be detected by 18SF- FDG-PET, and were diagnosed active tuberculosis with visual method. SUVmax(2. 77±1. 20) and SUV mean(2.15±0.86) were higher than SUVlung(0.41± 0.09, Z=-5. 232, P〈0.01 ; Z=- 5. 232, P〈0.01). Correlations were not found between SUVmax ,SUVmax and nodule size (Dmax, Dmin), SUVlung, age, blood glucose level in these 36 patients (P〉0.05). Seventeen fibrosis and calcification cases without caseous necrosis were not found abnormal in 18F-FDG-PET. Conclusion 18F- FDG- PET is useful in diagnosing active tuberculosis , extent of tuberculosis and guiding therapeutic regimen.

    Release date:2016-08-30 06:18 Export PDF Favorites Scan
  • Analysis of central retinal and choroidal morphology and thickness after photodynamic therapy for idiopathic choroidal neovascularization

    Objective To observe the retinal and choroidal changes in morphology and thickness after photodynamic therapy(PDT) for idiopathic choroidal neovascularization(ICNV). Methods Sixteen eyes of 16 patients with ICNV were treated with verteporfin PDT. 16 eyes of 16 agematched normal subjects were observed for the purpose of comparison. The best corrected visual acuity(BCVA) was checked before and 1, 3 and 6 months after PDT treatment. Enhanced depth imaging optical coherence tomography (EDI-OCT) technique was used to measure central retinal thickness (CRT) and central choroidal thickness(CCT). The correlations between BCVA and CRT, CCT were analyzed by Pearson statistical anallyses. Results BCVA was improved at 1, 3 and 6 months after PDT, and the difference had statistical significance compared with that before treatment (F=3.08,P=0.030). There was edema in the retina at 1 month after PDT. CNV in 13 eyes became fibrotic at 3 months after PDT, and all became fibrotic at 6 months after PDT. The reflex of choroid correspond to CNV was weak at 1, 3 and 6 months after PDT. CRT decreased at 1, 3 and 6 months after PDT (F=8.946,P=0.000). The difference was statistically significant between the CRT of control group and that 1 months after PDT (P=0.001), but there was no statistically significant difference between the CRT of control group and that 3 and 6 months after PDT(P=0.128, 0.083). The CCT group had no statistically significant difference before and 1, 3 and 6 months after PDT (F=1.674, P=0.170). The CCT group also had no statistically significant differences between the control group and 1, 3 and 6 months after PDT (P=0.186, 0.551, 0.98). The BCVA was inversely correlated with CRT and CCT, and the correlation had no statistical significance (r=-0.051,-0.164;P=0.739,0.283). Conclusions PDT may improve BCVA in ICNV. Retinal edema resolves, CRT decreases, but CCT had almost no changes after PDT.

    Release date:2016-09-02 05:37 Export PDF Favorites Scan
  • Analysis of the images of optical cohference tomography in the patients with macular hole caused by closed ocular trauma

    Objective To observe the features of the images of optical coherence tomograpy (OCT) in patients with traumatic macular hole (TMH), and detect the clinical significance of OCT. Methods Consecutive 74 patients (74 eyes) diagnosed with TMH by examinations of visual acuity, slit lamp, and direct or indirect ophthalmoscopy underwent optical coherence tomography (OCT). The analysis software of OCT was used to make the quantitative measurements of TMH. And the TMH were classified according to the morphological characteristics of the images of OCT. 50deg;color fundus photography was performed on the patients after OCT. The relationship of TMH with the average visual acuity, disease duration, average neuroepithelial thickness on the margin of hole, and the base diameter and the apex diameter of macular hole were retrospectively analyzed. Results The characterisctics of the images of 74 cases (74 eyes) of TMH were classified into 5 types: macular holes with symmetric edema of the neurosensory retina at the margin in 27 eyes (36.5%), macular holes with asymmetric edema of the neurosensory retina at the margin in 12 eyes (16.2%), macular hole with full-thickness defect of neurosensory retina without edema or detachment at the margin in 14 eyes (18.9%), macular hole with localized detachment of the neurosensory retina at the margin without edema in 17 eyes (23.0%), and macular hole with thinning neurosensory retina in 4 eyes ( 5.4%). There was no significant difference of visual acuity among different types of TMH (F=1.574, P=0.191). The visual acuity was positively related with the marginal retinal thickness (r=0.342, P=0.003), but not related to age, diameter of macular hole or the disease duration (r value was from -0.022 to -0.134,P value was from 0.863 to 0.261). The disease duration of Type IV TMH was shorter than that of other TMH types. In the patients with the disease duration over 90 days, Type I TMH was predominant. The average retinal thicknesses at the margin of the hole showed significant differences among different TMH types (F=13.921, P=0.000). Conclusions TMH could be divided into 5 types according to the characteristics of images of OCT; the clinical characteristics of different types of TMH varies. 

    Release date:2016-09-02 05:42 Export PDF Favorites Scan
  • The Clinic Value of Computed Tomography Examination in the Treatment of Uremic Pneumonia

    ObjectiveTo evaluate the value of computed tomography examination in the clinical diagnosis guidance and therapeutic effect assessment for patients with uremic pneumonia. MethodsWe reviewed the clinical situation and pathogenesis turnover of 64 cases of uremic pneumonia from February 2011 to January 2013,and analyzed the correlation between image modification and treatment effectiveness. ResultsSixty-four cases of uremic pneumonia had different image manifestations in each phase of the disease course,including 27 cases of pulmonary venous pleonaemia,51 of lung interstitial edema,8 of pulmonary alveoli effusion,and 15 of pulmonary interstitial fibrosis.Dropsy of serous cavity and the heart shape could be viewed by CT scanning.CT rechecking was carried out after hemodialysis and symptom-targeted treatment.The results showed that CT results of 27 cases of pulmonary venous pleonaemia,51 cases of edema in the interstitial tissue and 41 cases of pleural effusion changed significantly after treatment (P<0.001);the image manifestations of 8 cases of pulmonary alveoli edema also changed significantly (P<0.05);the CT result of 15 cases of pulmonary interstitial fibrosis had no change;six cases among the fourteen cases of pericardial effusion were not absorbed by treatment (P>0.05). ConclusionThe diagnosis of uremic pneumonia mainly depends on imaging results.CT scanning plays an important role on the determination of clinical stage,the choice of therapeutic method,and evaluation of curative effect for uremic pneumonia.

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