			Home About us Contact

Short Posterior Ciliary Artery (short + posterior_ciliary_artery)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Observer experience improves reproducibility of color doppler sonography of orbital blood vessels

JOURNAL OF CLINICAL ULTRASOUND, Issue 6 2002
János Németh MD
Abstract Purpose. The study investigated the reproducibility of orbital blood flow measurements with color Doppler imaging (CDI) at different stages of observer experience. Methods. The subjects were 31 healthy volunteers and 2 sequential groups of 25 glaucoma patients each. Repeated blood flow measurements (usually 3 sets) in orbital vessels (ophthalmic artery, short posterior ciliary arteries, central retinal artery, and central retinal vein) were performed by the same observer in a single session in each subject. Results. The parameters with the best reproducibility were the resistance index (mean coefficient of variation [COV], 3.3,8.8%), the peak systolic velocity (mean COV, 6.9,13.7%), the time-averaged velocity (mean COV, 7.2,16.0%), and the systolic acceleration time (mean COV, 8.8,12.3%). The mean COV was greater (9.9,20.3%) for the other arterial flow parameters (end-diastolic velocity and systolic acceleration) and for the venous flow velocities (maximum and minimum). The COVs of the parameters were improved by 20,40% as the observer became more experienced in ophthalmic CDI. Conclusions. We confirm the general reliability of CDI measurements in orbital vessels and show that observer experience improves reproducibility. It appears, however, that observer performance in these measurements is vessel specific. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:332,335, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10079 [source]

Colour Doppler examination of early and late orbital haemodynamic changes in eyes with eyelid oedema due to blunt trauma

ACTA OPHTHALMOLOGICA, Issue 2 2006
Mehmet Numan Alp
Abstract. Purpose:,To evaluate the early and late alterations in orbital blood flow parameters in eyes with severe eyelid swelling due to blunt trauma by using colour Doppler ultrasonography (CDU). Methods:,Blood flow parameters in the ophthalmic artery (OA), central retinal artery (CRA), short posterior ciliary arteries (SPCAs) and central retinal vein (CRV) were examined by CDU in 62 eyes of 31 patients with unilateral blunt trauma and in 32 eyes of 32 normal subjects. Patients were examined within the first 5 days and at least 1 month after trauma. The traumatized eyes of patients were designated ,trauma eyes', non-traumatized fellow eyes were designated ,fellow eyes', and randomly chosen eyes of control subjects ,control eyes'. Results:,In the early phase, peak systolic velocity (PSV) and end diastolic velocity (EDV) in the OA in trauma eyes were statistically significantly higher than in both fellow eyes and control eyes: the p-values for the differences in PSV and EDV between trauma eyes and fellow eyes were p < 0.001 and p = 0.001, respectively, while the p-values for the differences in PSV and EDV between trauma eyes and control eyes were p = 0.002 and p = 0.019, respectively). No other blood flow parameters obtained at the first examination in all groups were statistically different. In the late phase, PSV in the OA in trauma eyes was found to be higher than that in both fellow eyes and control eyes, but the difference was significant only between trauma eyes and fellow eyes (p = 0.028). End diastolic velocity in the CRA was statistically significantly lower in fellow eyes than in control eyes (p = 0.046). No other blood flow parameters in any vessels examined in fellow eyes and control eyes were statistically significantly different during the study period. Conclusion:,Blood flow velocities detected by CDU are increased in the OA in eyes with eyelid oedema due to blunt trauma and some of these changes may persist for up to 1 month. This effect seems to be a consequence of trauma-induced hyperaemia in the orbital soft tissues rather than an expression of traumatic choroidal vasculopathy. [source]

Doppler measurement of blood flow velocities in extraocular orbital vessels in patients with obstructive sleep apnea syndrome

JOURNAL OF CLINICAL ULTRASOUND, Issue 5 2003
C. Zuhal Erdem MD
Abstract Purpose. We used color Doppler sonography to determine blood flow velocities in the extraocular orbital vessels of patients with obstructive sleep apnea syndrome (OSAS) and compared the results with those of healthy control subjects without OSAS. Methods. Patients with OSAS were classified according to the apnea-hypopnea index (AHI) as having mild OSAS (AHI < 20) or severe OSAS (AHI , 20). The peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistance index were measured in the ophthalmic artery (OA), central retinal artery (CRA), lateral short posterior ciliary artery, and medial short posterior ciliary artery using color Doppler sonography. Only 1 eye was measured in each study participant, and right and left eyes were chosen randomly. The blood flow velocities of patients with OSAS and those of control subjects were compared with the Kruskal-Wallis test and Wilcoxon's rank-sum test. Results. The study comprised 30 patients (15 with mild and 15 with severe OSAS) and 20 healthy control subjects. Blood flow velocities were higher in most measured vessels in patients with OSAS than they were in the control subjects. Among patients with mild OSAS, the PSVs and EDVs in the posterior ciliary arteries were statistically significantly higher than those of the control group (p < 0.05), but those in the OA and CRA did not differ significantly between the mild OSAS group and the control group (p > 0.05). However, as the severity of OSAS increased, the PSVs and EDVs of the OA and CRA were also affected (p < 0.05). Conclusions. Color Doppler sonographic measurements of blood flow parameters in the orbital vessels may differ significantly between patients with OSAS and those without the syndrome. Therefore, OSAS should be considered in addition to other conditions when interpreting the results of color Doppler sonography of the extraocular orbital vessels if the clinical history points toward such a diagnosis. © 2003 Wiley Periodicals, Inc. 31:250,257, 2003 [source]

3254: Neurovascular coupling in the retrobulbar ciliary circulation

ACTA OPHTHALMOLOGICA, Issue 2010
O ZEITZ
Purpose Perfusion of the retina is adapted to the metabolic demand by neurovascular coupling. Neurovascular coupling has shown to be present in the retinal vasculature, but not in vessels supplying the optic nerve. The present study investigated the presence of neurovascular coupling in the anterior part of the optic nerve in healthy and glaucoma subjects. Methods Retrobulbar blood flow velocities were determined by color Doppler imaging (CDI). A Siemens Elegra ultrasound system with a 7.5L40 transducer was used. Peak-systolic and end-diastolic velocities (PSV and EDV) in the central retinal artery (CRA) or the short posterior ciliary artery (SPCA) were the primary readout. CDI measurements were performed shortly before, during, immediately after, 60 s after, and 120 s after a 10-Hz flicker stimulation of the retina. Results Thirty-five glaucoma patients and 44 healthy control subjects were included in the study. In the SPCA of healthy controls, flicker stimulation led to a rise of PSV from 9.7±0.8 to 12.5±0.8 cm/s (P<0.001; N=24) and of EDV from 2.4±0.3 to 3.6±0.3 cm/s (P<0.001; N=24). This effect was not detectable in glaucoma patients. In the CRA, flicker light led to an increase of EDV from 2.1±0.2 to 3.0±0.3 cm/s (P=0.002; N=20) in healthy volunteers and from 1.3±0.2 to 2.0±0.2 cm/s in glaucoma patients (P=0.004; N=15). PSV was affected by flicker stimulation in neither the healthy volunteers nor glaucoma patients. Conclusion The data indicate the presence of neurovascular coupling in the vascular bed supplied by the paraoptic SPCA. The response pattern to the flicker stimulus differs between healthy and glaucoma subjects. [source]

Predictors for visual field progression and the effects of treatment with dorzolamide 2% or brinzolamide 1% each added to timolol 0.5% in primary open-angle glaucoma

ACTA OPHTHALMOLOGICA, Issue 5 2010
Antonio Martínez
Abstract. Purpose:, This study aims to identify progression factors in patients with primary open-angle glaucoma (POAG), including the effects of treatment with dorzolamide 2% or brinzolamide 1%, each added to timolol 0.5%. Methods:, A sample of 161 POAG patients were prospectively randomized to receive either dorzolamide 2% (DT) or brinzolamide 1% (BT) b.i.d., each added to timolol 0.5%, during a 60-month, evaluator-masked study. Progression was determined by perimetric criteria. Factors associated with visual field progression were estimated using a conditional Cox hazard model with patient intraclass correlation and were expressed as hazard ratios (HRs) with 95% confidence intervals (95% CIs). Results:, Predictive baseline factors were lower diastolic blood pressure (DBP), lower mean arterial pressure (MAP), antihypertensive treatment, lower end-diastolic velocity (EDV) in the ophthalmic artery (OA) and short posterior ciliary artery (SPCA), and a higher resistivity index (RI) in the OA and SPCA. Progression risk decreased by approximately 30% and 20% with each centimetre per second increase of EDV in the OA and SPCA, respectively, from baseline to the last follow-up visit. Each RI decrease (or increase) of 0.01 unit in the OA or SPCA was associated with an approximate 20% decrease (or increase) in risk for progression. In a multivariate analysis, progression risk was significantly lower in eyes treated with DT (HR = 0.65, 95% CI 0.41,0.90) compared with those treated with BT. Conclusions:, Progression increased with lower DBP, lower MAP, antihypertensive medication, lower EDV in the OA and SPCA, and higher RI in the OA and SPCA. The risk for progression in patients treated with DT was half that in patients treated with BT. [source]