Improved estimation of low velocities in color Doppler imaging by adapting the mean frequency estimator to the clutter rejection filter

1996 ◽  
Vol 43 (9) ◽  
pp. 919-927 ◽  
Author(s):  
A. Herment ◽  
G. Demoment ◽  
P. Dumee
Keyword(s):  
Color Doppler ◽  
Color Doppler Imaging ◽  
Doppler Imaging ◽  
Mean Frequency ◽  
Clutter Rejection ◽  
Rejection Filter ◽  
The Mean ◽  
Frequency Estimator

Effect of Intravitreal Aflibercept on Central Retinal Arterial Blood Flow in Type 1 Retinopathy of Prematurity

2017 ◽  
Vol 27 (6) ◽  
pp. 751-755 ◽  
Author(s):  
Emine A. Sukgen ◽  
Gökhan Söker ◽  
Yusuf Koçluk ◽  
Bozkurt Gülek
Keyword(s):  
Blood Flow ◽  
Retinopathy Of Prematurity ◽  
Color Doppler ◽  
Color Doppler Imaging ◽  
Doppler Imaging ◽  
Intravitreal Aflibercept ◽  
Retinal Artery ◽  
The Mean ◽  
Type 1 Rop

Purpose To evaluate the blood flow changes of the central retinal artery measured with color Doppler imaging (CDI) in infants receiving intravitreal aflibercept (IVA) for treatment of type 1 retinopathy of prematurity (ROP). Methods Patients with type 1 ROP were assessed prospectively by CDI following IVA. Color Doppler imaging was used to measure the peak systolic velocity, end diastolic velocity (EDV), pulsatility index (PI), and resistivity index (RI) of the central retinal artery (CRA) before IVA injection and 1 hour, 1 week, and 1 month after injection. Results A total of 29 eyes of 15 infants were included in this study. The mean gestational age at birth was 28.62 ± 2.48 weeks and the mean birthweight was 1,198.62 ± 348.99 g. All treated eyes showed complete regression of ROP and peripheral retinal vascularization continued. Measurements of EDV-CRA, RI-CRA, and PI-CRA showed significant changes after IVA treatment. Conclusions This study showed that IVA is an effective treatment for type 1 ROP. After IVA treatment, vascular resistance increases, ocular blood flow decreases, and changes in hemodynamic parameters of CRA may remain for a month. Further studies are needed to evaluate the effect of anti-vascular endothelial growth factor agents on ocular hemodynamics in infants with ROP.

scholarly journals Comparison of Color Doppler Imaging Criteria for the Ophthalmic Artery and Central Retinal Artery in Infants with Retinopathy of Prematurity with and Without Plus Disease

2021 ◽  
Vol 18 (2) ◽  
Author(s):  
Marzieh Soleimani ◽  
Seyed Ehsan Ghetmiri ◽  
Mohammad Hossein Ahrar Yazdi
Keyword(s):  
Retinopathy Of Prematurity ◽  
Ophthalmic Artery ◽  
Color Doppler ◽  
Resistance Index ◽  
Color Doppler Imaging ◽  
Central Retinal Artery ◽  
Doppler Imaging ◽  
Significant Difference ◽  
Retinal Artery ◽  
The Mean

Background: Color Doppler imaging (CDI) is a non-aggressive and safe technique for the clinical management of retinal diseases. Recently, the number of infants with retinopathy of prematurity (ROP) has increased due to the incidence of premature births. Objectives: This study aimed to compare the CDI criteria for the ophthalmic artery (OA) and central retinal artery (CRA) in ROP infants with and without plus disease. Patients and Methods: In this case-control study, 42 premature infants (21 infants with plus disease and 21 infants without plus disease) underwent CDI. The arterial CDI parameters, including end-diastolic velocity (EDV), pulsatility index (PI), resistance index (RI), and peak systolic velocity (PSV), were measured in these patients. After collecting the data, t-test and chi-square tests were used for data analysis. P < 0.05 was considered to be statistically significant. Results: The mean EDV of CRA in patients with and without plus disease was 4.35 ± 1.00 and 5.27 ± 1.02 cm/sec, respectively (P = 0.005). The mean PSV of CRA in patients with and without plus disease was 15.65 ± 3.35 and 18.39 ± 4.39 cm/sec, respectively (P = 0.029). However, no significant difference was found between the two groups in terms of PSV or EDV of OA (P > 0.05). Also, no significant difference was observed between the two groups considering the RI and PI of CRA and OA (P > 0.05). Conclusion: According to the findings of this study, CDI criteria, such as EDV and PSV of CRA, were significantly lower in infants with plus disease as compared to those without plus disease. Since detecting the early stages of plus disease is a challenge for ophthalmologists, assessment of these criteria can be helpful for differentiation of these two subgroups of patients. However, further studies with a larger sample size are needed to determine the cutoff value.

Adaptive Clutter Rejection for 3D Color Doppler Imaging: Preliminary Clinical Study

2008 ◽  
Vol 34 (8) ◽  
pp. 1221-1231 ◽  
Author(s):  
Yang Mo Yoo ◽  
Siddhartha Sikdar ◽  
Kerem Karadayi ◽  
Orpheus Kolokythas ◽  
Yongmin Kim
Keyword(s):  
Clinical Study ◽  
Color Doppler ◽  
Color Doppler Imaging ◽  
Doppler Imaging ◽  
Clutter Rejection ◽  
3D Color Doppler

Color Doppler Imaging Study in Patients with Primary Open-Angle Glaucoma Treated with Timolol 0.5% and Carteolol 2%

2001 ◽  
Vol 11 (3) ◽  
pp. 240-244 ◽  
Author(s):  
P. Montanari ◽  
P. Marangoni ◽  
A. Oldani ◽  
R. Ratiglia ◽  
M. Raiteri ◽  
...  
Keyword(s):  
Intraocular Pressure ◽  
Primary Open Angle Glaucoma ◽  
Open Angle Glaucoma ◽  
Color Doppler ◽  
Resistance Index ◽  
Color Doppler Imaging ◽  
Doppler Imaging ◽  
Open Angle ◽  
Significant Difference ◽  
The Mean

Purpose To evaluate with color Doppler imaging (CDI), in patients with primary open-angle glaucoma (PDAG), the possible influence on ocular hemodynamics of a beta-blocking agent with intrinsic sympathomimetic acitivity (carteolol 2%) compared to a beta-blocker agent without this activity. Methods A study was carried out on 20 patients, with bilateral POaG, intraocular pressure (IOP) ≤ 20 mmHg, all treated twice a day with timolol maleate 0.5% ophthalmic solution. The visual field was evaluated (Octopus 2000 perimeter, G1 program) examining the mean sensitivity (MS) and the mean defect (MD). CDI was carried out to evaluate the resistance index of the internal carotid artery (ICA), the ophthalmic artery (OA), the central retinal artery (CRA), and the short posterior ciliary arteries (SPCA). After these examinations, the therapy was changed to carteolol 2% twice a day. After six months of treatment the examinations were repeated. The data were analysed statistically using Student's t test. Results The mean intraocular pressure during treatment with timolol 0.5% was 16.7 ± 1.67 mmHg and 16.33 ± 1.72 mmHg after treatment with carteolol 2%, the difference not being significant (p=0.494). After six months of treatment with carteolol 2% the MS increased significantly from 22.4 ± 2.5 dB to 24.1 ± 1.8 dB (p=0.018), and the mean defect (MD) fell from 5.3 ± 0.8 dB to 4.7 ± 0.6 dB (p=0.011). There was no significant difference in the resistance index of the CA, the OA and the CRA with the two treatments, whereas the resistance index of the SPCA dropped significantly, from 0.80 ± 0.05 to 0.77 ± 0.02 (p = 0.017). Conclusions CDI did not show significant differences in the resistance indexes of the internal CA, the OA, and the CRA after treatment with carteolol 2% but the resistance index of the SPCA was significantly reduced. Carteolol 2% induced significant changes in the perimetric indexes examined, with an increase in MS and a decrease in MD. These findings suggest that the intrinsic sympathomimetic activity of carteolol may reduce peripheral vascular resistance of the SCA, thus improving perfusion of the optic nerve head, with a protective effect on visual function.

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