Carotid System (carotid + system)

Distribution by Scientific Domains
Medical Sciences100%

Selected Abstracts

Assessment of Carotid Compliance Using Real Time Vascular Ultrasound Image Analysis in Marfan Syndrome

ECHOCARDIOGRAPHY, Issue 4 2009
Anatoli Kiotsekoglou M.D.
Background: Fibrillin-1 deficiency, dysregulated cytokine transforming growth factor-,, and increased collagen deposition related to fibrillin-1 gene mutations could predispose to impaired carotid compliance (CC) in Marfan syndrome (MFS). We sought to detect any alterations in CC using the vascular image analysis system (VIA). Methods and Results: Thirty-two MFS patients, 20 men and 12 women (mean age 34.2 ± 12.05 years), and 29 controls matched for age, sex, and body surface area (BSA) were recruited. The entire length of each carotid system was initially scanned longitudinally using a 14 MHz linear transducer. Then, a stereotactic clamp held the transducer in contact with the carotid artery. Arterial diameter changes during the cardiac cycle were recorded for 1 minute from both right (RCCA) and left common carotid arteries (LCCA) separately using the VIA system. RCCA and LCCA compliance and distensibility measurements were significantly reduced in MFS patients when compared to controls, P < 0.05. RCCA and LCCA intima-media thickness did not differ between patients and controls, P > 0.05. MFS diagnosis and age were associated with reduced CC in both carotid arteries after adjusting for variables such as, sex, BSA, heart rate, beta-blockade, intima-media thickness, and aortic root size. Conclusions: Our findings showed a reduction in CC in adult patients with MFS. This could be attributed to fibrillin-1 deficiency resulting in structural abnormalities in the carotid arterial wall. [source]

Bilateral common carotid occlusion without neurological deficit

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 4 2002
Serdar Karaköse
Summary A 40-year-old man presented with pain and numbness in his right arm. On his clinical examination, no neurological deficit was found. Bilateral common carotid artery duplex sonography scan demonstrated no flow in either lumen. No abnormality was recognized on brain CT. On cerebral digital substraction angiogram, total occlusion of the brachiocephalic trunk and left carotid artery were shown. There was a modest stenosis in the left vertebral artery. Collateral circulation feeding the intracranial carotid system mainly originated from the left vertebrobasilar system. Previous cases of bilateral carotid occlusion are reviewed and discussed. [source]

Embolization of indirect carotid-cavernous sinus fistulas using the superior ophthalmic vein approach

ACTA NEUROLOGICA SCANDINAVICA, Issue 3 2004
J. Baldauf
Objectives , In indirect carotid-cavernous sinus fistulas (CCF), abnormal connections exist between tiny dural branches of the external and/or internal carotid system and the cavernous sinus. Usually this kind of fistula occurs spontaneously and is characterized by a low shunt volume. Alternative vascular approaches for embolization are required when standard interventional neuroradiological access via arterial or transfemoral venous routes is not feasible. Patients and methods , Two symptomatic patients with indirect CCFs are described. Transarterial and transfemoral venous approach was unsuccessful or resulted in incomplete occlusion of the CCF. Therefore, the superior ophthalmic vein (SOV) was surgically exposed and retrograde catheterized to allow the delivery of platinum coils to the fistula point via a microcatheter. Results , Complete fistula obliteration was accompanied by recovery of the clinical symptoms. Conclusion , The surgical SOV approach might be sufficient when standard neuroradiological procedures do not succeed. The technique is safe and effective when performed by an interdisciplinary team. [source]

Autoregulation in the choroid

ACTA OPHTHALMOLOGICA, Issue 2009
S ORGUL
Purpose To compare subfoveal choroidal blood flow (ChBF) in sitting and supine position in normal volunteers. Methods ChBF was measured with laser Doppler flowmetry in 22 healthy volunteers (mean age ± SD: 24 ± 5 years). Six independent measurements of choroidal blood flow were obtained in one randomly selected eye of each subject. Subsequently, the subjects assumed a supine position for 30 minutes and a new series of 6 measurements was obtained. Parallel hereto, systemic blood pressure and intraocular pressure were measured. Ocular perfusion pressure (OPP) was calculated based on formulas derived from ophthalmodynamometric studies. The influence of changing OPP on the change in ChBF was assessed in a linear regression analysis. Results The coefficient of variation for ChBF was 10.28% and 9.58% in the sitting and the supine position respectively. ChBF decreased by 6.6% (p=0.0017) in the supine position. The estimate for ophthalmic blood pressure in the supine position was adjusted to obtain a result of no change in OPP for no change in ChBF, yielding an average decrease for the estimate of OPP of 6.7% (p=0.0002). Change in OPP correlated significantly with change in ChBF (R2: 0.20; p=0.036) with a slope for the regression line of 1.04. Conclusion The comparable degree of change in ChBF and OPP and the linear relationship between the two parameters suggest a passive response of the choroidal circulation to the posture change. In contrast, the OPP estimates suggest a marked buffering of the change in perfusion pressure by the carotid system, compatible with a close control of the gradient in perfusion pressure between the heart and its branches within the carotid system. [source]

Relationship between ocular pulse amplitude and systemic blood pressure measurements

ACTA OPHTHALMOLOGICA, Issue 3 2009
Matthias C. Grieshaber
Abstract. Purpose:, This study aimed to determine whether ocular pulse amplitude (OPA) measured with dynamic contour tonometry (DCT) is related to systemic blood pressure (BP) parameters. Methods:, Blood pressure was measured continuously and simultaneously with OPA in one randomly selected eye in 29 healthy subjects. Systemic parameters of interest were: systolic and diastolic BPs and their difference (BP amplitude), and left ventricle ejection time (LVET; defined as the time between the diastolic trough and the incisural notch in the BP curve). In addition, the axial length (AL) of the eye was measured. Associations between OPA, AL and systemic cardiovascular parameters were analysed in a multivariate regression model. Results:, Measurements of OPA ranged from 1.0 mmHg to 4.9 mmHg (mean 2.3 ± 0.9 mmHg, median 1.9 mmHg). In a univariate analysis with one predictor at a time, means of intraocular pressure (IOP) (p = 0.008), AL (p = 0.046) and LVET (p = 0.037) were significantly correlated with OPA, whereas systolic and diastolic BPs and their amplitude were not. A multiple linear regression analysis showed that mean IOP (p < 0.005), AL (p = 0.01) and LVET (p = 0.002) all independently contributed to OPA. Conclusions:, The OPA readings measured with DCT in healthy subjects were not related to BP levels and amplitude. It seems that the OPA strongly depends on the time,course of the cardiac contraction. Regulating mechanisms in the carotid system as well as scleral rigidity may be responsible for dampening the direct effect of BP variations. [source]