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find Keyword "blood flow" 66 results
  • Correlations between macular microvascular parameters in patients with type 2 diabetes mellitus and urinary albumin creatinine ratio

    ObjectiveTo observe and analyze the correlation between macular microvascular parameters and urinary albumin to creatinine ratio (UACR) in patients with type 2 diabetes mellitus (T2DM). MethodsA cross-sectional study. From October 2017 to April 2018, 100 eyes of 100 patients (T2DM) and 27 eyes of 27 healthy controls (the control group) were enrolled in Xuzhou First People’s Hospital. All subjects underwent anterior segment examination via slit-lamp biomicroscopy, dilated fundus examination, 7-field fundus photographs, OCT angiography (OCTA), the fasting glucose test, glycosylated hemoglobin (HbA1c), urinary albumin, urinary creatinine and UACR levels determination. Height and weight measurement were taken for calculating body mass index (BMI). Diabetic retinopathy was ruled out by fundoscopic examinations and 7-field fundus photographs in T2DM patients. According to the UACR, patients in the T2DM group were subdivided into A1 group (UACR< 30 mg/g), A2 group (UACR 30-300 mg/g), and A3 group (UACR>300 mg/g), with 38 cases and 38 eyes respectively , 40 cases with 40 eyes, 22 cases with 22 eyes. A 6 mm×6 mm scanning area centered on the macular fovea were scanned for right eye using a frequency domain OCTA instrument, which were divided into three concentric circles centered on the macular fovea by the software automatically. The foveal zone was defined as a circular area measuring 1 mm in diameter, the parafoveal zone was described as a middle circle area measuring 1-3 mm in diameter, and the perifoveal zone was an outer circle area measuring 3-6 mm in diameter. The vessel density of superficial capillary plexus (SCP) and deep capillary plexus (DCP), foveal avascular area (FAZ) and perimeter (PERIM), non-circularity index (AI) were measured. The correlation between the macular vessel density, FAZ and UACR was analyzed by Spearman correlation analysis. ResultsA1 group, A2 group, A3 group, and normal control group. The macular area SCP and DCP (F=13.722, 5.644), foveal area (F=4.607, 4.719), parafoveal area (H=23.142, F=2.904), the blood flow density of the area around the fovea (F=12.292, H=10.946), the difference was statistically significant (P<0.05); with the increase of UACR, the blood flow density of each area of SCP and DCP showed a downward trend. The results of correlation analysis showed that the blood flow density of the whole SCP, parafoveal area, and surrounding area of T2DM patients was negatively correlated with UACR (r=-0.376, -0.240, -0.364, -0.347, P<0.05). There were no correlation among fasting plasma glucose, HbAlc and UACR (r=0.179, 0.085, P>0.05). There were no correlation among blood flow density in BMI, SCP foveal area, DCP and UACR (|r|<0.3, P>0.05). ConclusionThe whole, parafovea and perifovea vessel density values of SCP in T2DM eyes without DR are negatively correlated with UACR.

    Release date:2022-05-18 04:03 Export PDF Favorites Scan
  • Application of transcranial Doppler monitoring cerebral blood flow in operation with anesthesia

    There are a variety of invasive or non-invasive methods for monitoring cerebral blood flow and cerebral metabolism in patients during operation with anesthesia, and different methods have their own scope of use. Transcranial Doppler can be used to monitor high-risk patients with intraoperative cerebral blood flow autoregulation dysfunction and patients with special positions during operation because of its convenience, continuity, and strong repeatability. Changes in cerebral blood flow detected by transcranial Doppler may be associated with postoperative central nervous system complications in patients. This article reviews the application of transcranial Doppler monitoring of cerebral blood flow in operation with anesthesia, aiming to provide a certain basis for the promotion of this technology in operation with anesthesia.

    Release date:2022-02-24 02:27 Export PDF Favorites Scan
  • Research progress on choroidal layer changes in eyes with retinal vein occlusion

    Retinal vein occlusion (RVO) is a serious retinal vascular disease, often accompanied by systemic cardiovascular and cerebrovascular diseases, the eye changes include macular edema, retinal ischemia, and even neovascularization, etc. As a common chronic disease of the fundus, it seriously affects patients' vision and quality of life. With the development of optical coherence tomography, the role of choroid in the occurrence and development of RVO has become a research hotspot. The research on the changes of the choroid layer of the eye with RVO has expanded from a simple two-dimensional thickness analysis to a more comprehensive multidimensional observation index such as three-dimensional volume, blood flow density and velocity. In addition, some cutting-edge research combines artificial intelligence algorithm techniques to improve the accuracy and depth of analysis. In the future, it is still necessary to further improve the data of the choroid layer of the eye with RVO, enhance the overall understanding of RVO, and provide new ideas for clinical prevention and treatment of RVO.

    Release date:2025-02-25 09:39 Export PDF Favorites Scan
  • The fast blood flow density of intermediate choroid in endogenous Cushing syndrome: analysis of optical coherence tomography angiography

    ObjectiveTo compare the fast blood flow density (FBFD) of intermediate choroid between endogenous Cushing syndrome (ECS) patients and healthy control subjects.MethodsThirteen eyes of 7 eligible ECS patients (ECS group) and 13 eyes of 7 gender, age, axial length matched healthy volunteers (control group) were enrolled in this study. For each subject, macular radial scan with swept source optical coherence tomography (SS-OCT) was performed and subfoveal choroidal thickness (SCT) was measured. Then 3.0 mm×3.0 mm macular scan with SS-OCT angiography was performed, and selected blood flow image at intermediate choroid level or 1/2 SCT beneath Bruch membrane. The grayscale images were then binarized for the analysis of FBFD.ResultsThe SCT in ECS group was (394.7±77.7) μm, which was significantly thicker than (332.1±68.1) μm in control group (t=2.923, P=0.008). The FBFD of intermediate choroid in ECS group were (76.35±14.46)%, which were significantly greater than (63.57±13.42)% in control group (t=2.775, P=0.01).ConclusionECS patients had increased FBFD at intermediate choroid level compared with healthy controls.

    Release date:2017-07-17 02:38 Export PDF Favorites Scan
  • The changes of macular blood flow density in patients of macular telangiectasis type 1 with macular edema before and after the treatment of anti-vascular endothelial growth factor

    ObjectiveTo observe the changes of macular blood flow density in patients of macular telangiectasis type 1 (Mac-Tel type 1) with macular edema before and after the treatment of anti-VEGF.MethodsA retrospective clinical study. From January 2016 to December 2017, 14 Mac-Tel type 1 patients (14 eyes) diagnosed in Nanjing Medical University Eye Hospital were included in the study. There were 6 males (6 eyes) and 8 females (8 eyes), with the mean age of 35.3±9.3 years. All patients underwent BCVA and OCT angiography examinations. The BCVA examination was performed using the Snellen visual acuity chart, which was converted into logMAR visual acuity. All the patients were received anti-VEGF injection treatment once a month for 3 consecutive months. The OCTA scanning region in the macular area was 3 mm × 3 mm. Macular blood flow density in the superficial capillary plexus (SCP) and deep capillary plexus (DCP), the vessel density within a 300 μm width ring surrounding the foveal avascular area (FD-300) and central macular thickness (CMT) were measured in all eyes. Paired samples t-test and Pearson correlation analysis were used in this study.ResultsAt the baseline, logMAR BCVA was 0.69±0.07, CMT was 468.43±26.59 μm, SCP blood flow density was (50.99±1.19)%, DCP blood flow density was (43.79±1.44)%, FD-300 was (50.73±1.16)%. Compared with the baseline, there were significant differences between logMAR BCVA, CMT, DCP blood flow density and FD-300 in 1 week, 1 month, 3 months after treatment and 2 months after cessation of treatment (logMAR BCVA: t=6.77, 13.30, 16.99, 9.51; P=0.00, 0.01, 0.00, 0.01. CMT: t=6.99, 15.88, 26.10, 6.50; P=0.00, 0.01, 0.01, 0.00. DCP: t=6.75, 8.61, 15.12, 7.63; P=0.00, 0.01, 0.01, 0.00. FD-300: t=11.86, 13.08, 14.36, 4.41; P=0.00, 0.01, 0.01, 0.03). There was no significant difference in blood flow density of SCP between baseline and 2 months after cessation of treatment (t=1.36, P=0.19), but there was significant difference at the other time points after treatment (t=5.50, 6.84, 6.27; P=0.00, 0.01, 0.01). The Pearson's correlation analysis showed that there was a significant positive correlation between FD-300 and CMT (r2=0.54, P=0.04).ConclusionsThere is no significant change in the SCP blood flow density in the patients of Mac-Tel type 1 with macular edema, while the DCP blood flow density decreased and FD-300 increased. After anti-VEGF treatment, DCP blood flow density increased and FD-300 decreased. FD-300 is positively correlated with CMT.

    Release date:2020-02-18 09:28 Export PDF Favorites Scan
  • Observation on the imaging characteristics of optical coherence tomography angiography in eyes with macular telangiectasia type 2

    ObjectiveTo observe the imaging characteristics of optical coherence tomography angiography in macular telangiectasia type 2 (Mac-Tel 2). MethodsA retrospective case analysis. From October 2017 to June 2021, 11 patients (22 eyes) diagnosed as Mac-Tel type 2 by multi-modal imaging in Nanjing Medical University Eye Hospital were included in this study. There were 5 males (10 eyes) and 6 females (12 eyes). The age were 41.61±11.32 years old. All patients underwent the examinations of best corrected visual acuity, indirect ophthalmoscope, fundus color photography, fluorescein fundus angiography (FFA), optical coherence tomography (OCT), and OCT angiography (OCTA). The scope of 3 mm × 3 mm in macular area of eyes was scanned by OCTA. After automatic image processing, the system could provide the blood flow image of capillary layer, deep capillary layer, outer retina, choroidal capillary layer, and the B-scan image. The imaging characteristics were observed. ResultsAmong the 22 eyes, 14 eyes were in the early stage of the disease, and 8 eyes had secondary subretinal neovascularization (SRN) and/or choroidal neovascularization (CNV). FFA examination that in the early stage of the disease, the capillaries near the fovea were dilated, the blood vessels were stretched, and the late fluorescence was mainly stained; high-fluorescence leakage was seen when SRN and CNV were developed. OCTA examination showed that in the early stage of the disease, the temporal capillaries in the macular area were dilated and stretched, especially in the deep layer. The capillary space was enlarged, and the right-angled venules were seen to change and infiltrate into the deep layer; when the lesions invaded the outer retina, flower clusters-like SRN were seen; neovascularization was seen in the outer retina and choroidal capillary layer when CNV was developed. B-scan image showed that in the early stage of the disease, irregular weak reflex cavities and lamellar holes change between the neuroepithelial layers; secondary SRN and CNV showed strong little clumpy reflexes accompanied by abundant blood flow signals. ConclusionThe image characteristics of OCTA in the eyes of Mac-Tel 2 were dilated, stretched superficial and deep temporal capillaries in the macula area and right-angled changes in blood vessels.

    Release date:2022-01-19 03:48 Export PDF Favorites Scan
  • Multimodal imaging features of tamoxifen retinopathy

    ObjectiveTo observe the multimodal imaging characteristics of tamoxifen retinopathy. MethodsA retrospective case study. From January 2019 to December 2021, 4 patients (8 eyes) with tamoxifen retinopathy diagnosed in Tangshan Eye Hospital were included in the study. All patients were female, with sick binoculus. The age was 59.5±4.6 years. After breast cancer resection, tamoxifen 20 mg/d was taken orally consecutively, including 1, 1, and 2 cases who took tamoxifen orally for 5, 7, and ≥10 years. All eyes were examined by fundus color photography, optical coherence tomography (OCT), OCT angiography (OCTA), fundus fluorescein angiography (FFA), and fundus autofluorescence (AF). The multi-mode image features of the fundus of the affected eyes were observed. ResultsThe yellow white dot crystal like material deposition in the macular area was observed in all eyes. In fundus AF examination, macular area showed patchy strong AF. FFA examination showed telangiectasia and fluorescein leakage in macular area at late stage. OCT showed that punctate strong reflexes could be seen between the neuroepithelial layers in the macular region with the formation of a space between the neuroepithelial layers, the interruption of the elliptical zone (EZ), and the formation of a hole in the outer lamella including 4, 5 and 3 eyes; The thickness of ganglion cells in macular region decreased in 7 eyes. OCTA showed that the blood flow density of the superficial retinal capillary plexus around the arch ring was decreased, and the retinal venules were dilated in 2 eyes; Deep capillary plexus (DCP) showed telangiectasia. ConclusionDeposition of yellowish white dot like crystals can be seen in the macular region of tamoxifen retinopathy; dotted strong reflex between neuroepithelial layers, cavity formation, thinning of ganglion cell layer, EZ middle fissure and outer lamellar fissure; DCP capillaries and venules around the arch were dilated; telangiectasia in macular region; flaky strong AF in macular region.

    Release date:2022-12-16 10:13 Export PDF Favorites Scan
  • The comparison of macular blood flow parameters in myopic choroidal neovascularization, high myopia and normal people

    ObjectiveTo compared the macular blood flow parameters among myopic choroidal neovascularization (mCNV), high myopia (HM) and normal subjects.MethodsRetrospective study. Forty patients (40 eyes) diagnosed as mCNV (mCNV group) in the Eye Hospital of Wenzhou Medical University at Hangzhou from June 2016 to November 2018, age-matched, sex-matched and diopter-matched 40 HM patients (40 eyes, HM group), age-matched and sex-matched 40 healthy persons (40 eyes, normal group) were enrolled in this study. Retina superficial and deep vessel density, the area of foveal avascular zone (FAZ), a-circularity index (AI) and vessel density around the 300 μm width of the FAZ region (FD) on macular 3 mm×3 mm scan on OCTA of 3 groups were compared.ResultsThere were significant differences in the average retina superficial, deep vessel density, the area of FAZ, AI and FD among 3 groups (F=24.82, 9.18, 3.58, 7.68, 14.15; P<0.05). The average retina superficial and deep vessel density and FD in mCNV group were lower than those in HM group (P<0.05). The average retina superficial and deep vessel density and FD in HM group were lower than those in control group (P<0.05). The average area of FAZ in mCNV group was smaller than that in control group (P<0.05). The average AI in mCNV group was less than that in the other 2 groups (P<0.05).ConclusionsThe retina superficial, deep vessel density and FD decreased, the area and the form of FAZ remained unchanged in HM subjects comparing with normal subjects. While retina superficial, deep vessel density and FD decreased more, the area of FAZ reduced, the form of FAZ tend to be irregular in mCNV.

    Release date:2019-11-19 09:24 Export PDF Favorites Scan
  • EFFECT OF ENDOTHELIN-1 ON HEPATIC BLOOD FLOW IN RATS

    In order to study effect of endothelin (ET-1) on hepatic blood flow in rats and effect of nitric oxide (NO) and prostacyclin (PGI2) on ET-1 biological function, 20 rats were randomized into control, ET-1, ET-1 plus nitric-Larginine, ET-1 plus prostacyclin and indomethen groups. The result showed that ET-1 decreased hepatic blood flow and lasted for longer time. NO and PGI2 may antagonize the biological action of ET-1 during endotoxemia. Therefore, the endothelium-derived vascular factors may regulate hepatic blood flow.

    Release date:2016-08-29 03:18 Export PDF Favorites Scan
  • The macular structure and blood flow in familial exudative vitreoretinopathy with inner retinal layer persistence

    Objective To compared the changes of macular microvascular architecture in early stage familial exudative vitreoretinopathy (FEVR) patients with inner retinal layer (IRL) persistence and without IRL persistence. MethodsA retrospective clinical study. From 2017 to 2022, 94 patients with stage 1 FEVR with or without IRL residue and 45 age- and sex-matched healthy volunteers with 45 eyes (normal control group) who were confirmed by ophthalmology examination in Hangzhou Hospital of Optometry Affiliated to Wenzhou Medical University and Zhejiang Provincial People's Hospital were included in the study. According to whether there was IRL residue, the patients were divided into IRL group and non-IRL group, with 22 patients (22 eyes) and 72 patients (72 eyes), respectively. Best corrected visual acuity (BCVA) and optical coherence tomography angiography (OCTA) were performed in all eyes. Superficial vessel density (SCP) and deep vessel density (DCP) of whole image, fovea and parafovea, the area and perimeter of fovea avascular area (FAZ), A-circularity index (AI, perimeter/standard circle perimeter with equal area) and vessel density around the 300 μm width of the FAZ (FD), central macular thickness (CMT) on macular 3 mm × 3 mm scan on OCTA were measured. ResultsSCP and DCP of whole image (F=10.774, 4.583) and parafovea (F=10.433, 3.912), CMT (F=171.940) in IRL group and non-IRL group on macular 3 mm × 3 mm scan on OCTA were significantly lower than that in normal persons (P<0.05). There were significant differences among three groups of the area of FAZ (F=4.315), AI (F=3.413), FD-300 (F=13.592) (P<0.05). BCVA were worst in IRL group (P<0.05). ConclusionsBlood flow density decreased in macular area of FEVR patients. CMT is significantly thicker than normal population. The FAZ area of the foveal IRL residual eyes is small and irregular, with worse BCVA and lower macular blood density.

    Release date:2023-08-17 08:49 Export PDF Favorites Scan
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