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Ophthalmic Artery (ophthalmic + artery)
Selected AbstractsOphthalmic Artery Flow Direction on Color Flow Duplex Imaging Is Highly Specific for Severe Carotid StenosisJOURNAL OF NEUROIMAGING, Issue 1 2002Patrick S. Reynolds MD Background/Purpose. Collateral flow patterns are important risk factors for brain ischemia in the presence of internal carotid artery (ICA) stenosis or occlusion. Ophthalmic artery (OA) flow reversal, routinely studied by transcranial Doppler sonography, is an important marker for high-grade ICA stenosis or occlusion. The authors sought to define the value of assessing OA flow direction with color flow duplex ultrasonography (CDUS) in the setting of significant ICA disease. Methods. Of all patients having routine carotid ultrasound in the neurosonology laboratory between July 1995 and November 2000, 152 had both carotid and orbital (OA flow direction by reduced power orbital CDUS) examinations as well as angiographic confirmation of stenosis to which North American Symptomatic Carotid Endarterectomy Trial criteria could be applied. Degree of angiographic stenosis in these 152 patients (304 arteries) was correlated with OA flow direction. Results. Of 304 arteries, 101 had greater than 80% stenosis by angiogram. In 56 of these 101 arteries with high-grade stenosis or occlusion, the ipsilateral OA was reversed; however, OA flow direction was never reversed ipsilateral to arteries with less than 80% stenosis (sensitivity 55%, specificity 100%, negative predictive value 82%, and positive predictive value 100% for OA flow reversal as a marker of high-grade carotid lesions). Discussion/Conclusions. OA flow direction is easily studied with CDUS. Reversed OA flow direction is highly specific (100%) for severe ipsilateral ICA stenosis or occlusion, with excellent positive predictive value, moderate negative predictive value, and limited sensitivity. OA flow reversal is not only quite specific for severe ICA disease, which may be helpful if the carotid CDUS is difficult or inadequate, but may also provide additional hemodynamic insights (ie, the inadequacy of other collateral channels such as the anterior communicating artery). OA evaluation can provide important hemodynamic information and should be included as part of carotid CDUS if there is any evidence of ICA stenosis or occlusion. [source] Application of an adaptive neuro-fuzzy inference system for classification of Behcet disease using the fast Fourier transform methodEXPERT SYSTEMS, Issue 2 2007Necaattin Bari Abstract: In this study, ophthalmic arterial Doppler signals were obtained from 200 subjects, 100 of whom suffered from ocular Behcet disease while the rest were healthy subjects. An adaptive neuro-fuzzy inference system (ANFIS) was used to detect the presence of ocular Behcet disease. Spectral analysis of the ophthalmic arterial Doppler signals was performed by the fast Fourier transform method for determining the ANFIS inputs. The ANFIS was trained with a training set and tested with a testing set. All these data sets were obtained from ophthalmic arteries of healthy subjects and subjects suffering from ocular Behcet disease. Performance indicators and statistical measures were used for evaluating the ANFIS. The correct classification rate was 94% for healthy subjects and 90% for unhealthy subjects suffering from ocular Behcet disease. The classification results showed that the ANFIS was effective at detecting ophthalmic arterial Doppler signals from subjects with Behcet disease. [source] Cluster headache: aetiology, diagnosis and management.HEADACHE, Issue 3 2003K Ekbom Drugs. 2002;62(1):61-69 Cluster headache is characterised by repeated attacks of strictly unilateral pain in the orbital region associated with local autonomic symptoms or signs. The attacks are brief but of a very severe, almost excruciating intensity. For unknown reasons males are affected more often than females. Recent studies suggest that an autosomal dominant gene has a role in some families with cluster headache. Hormonal studies indicate a dysfunction in the central nervous system. Neuroimaging has revealed primary defects in the hypothalamic grey matter. Local homolateral dilatation in the intracranial segment of the internal carotid and ophthalmic arteries during attacks is the result of a generic neurovascular activation, probably mediated by trigeminal parasympathetic reflexes. Sumatriptan 6mg subcutaneously is the drug of choice in the treatment of acute attacks. Inhalation of 100% oxygen can also be recommended. In the prophylactic treatment, verapamil is the first option. Other drugs that can be considered are corticosteroids, which may induce a remission of frequent, severe attacks, and lithium. Oral ergotamine tartrate may be sufficient for patients with night attacks and/or short, rather mild to moderately severe cluster headache periods. Third line drugs are serotonin inhibitors (methysergide and pizotifen) and valproic acid. Patients should be encouraged to keep headache diaries and be carefully instructed about the nature and treatment of the headaches. Alcohol can bring on extra attacks and should not be consumed during active periods of cluster headache. Comment: A useful review of clinical options. Given the effectiveness of injectable sumatriptan and the prophylactic use of ergotamine mentioned, one might speculate that the new intranasal formulations of triptans (eg, zolmitriptan) and triptans with a longer half-life (eg, frovatriptan) may prove to be effective in the treatment of cluster headache. DSM [source] Ultrasound assessment of short-term ocular vascular effects of intravitreal injection of bevacizumab (Avastin®) in neovascular age-related macular degenerationACTA OPHTHALMOLOGICA, Issue 6 2010Philippe Bonnin Acta Ophthalmol. 2010: 88: 641,645 Abstract. Purpose:, Angiogenic inhibitors, alone or combined with other therapies, are believed to represent a promising treatment for neovascularization in age-related macular degeneration (wet AMD). They can maintain or improve visual acuity (VA), at least for the first 2 years. However, evolution to retinal atrophy cannot be ruled out and it may be useful to assess the effects of antiangiogenic therapy on retinal and choroidal circulation. Methods:, We carried out a pilot study in 15 patients with wet AMD. Time-averaged mean blood flow velocities (BFVs) in the central retinal, temporal posterior ciliary and ophthalmic arteries (CRA, TPCA and OA) were measured by ultrasound imaging before and 4 weeks after a single intravitreal injection of 1.25 mg bevacizumab in 0.05 ml. Patients underwent two ophthalmic examinations, before and 4 weeks after injection, including VA measurement and optical coherence tomography (OCT3) examination. Results:, In treated eyes, bevacizumab injection was followed by a significant improvement in VA (from 20/125 to 20/80; p = 0.0214), and a decrease in mean central macular thickness (from 392 ± 96 ,m to 271 ± 50 ,m; p = 0.0038). Mean BFV decreased by 10% in the CRA (p = 0.0226), 20% in the TPCA (p = 0.0026) and 20% in the OA (p = 0.0003). No effect was observed in fellow eyes. Conclusions:, Intravitreal bevacizumab acutely improved VA and reduced central macular thickness in wet AMD. Ultrasound imaging revealed that BFVs decreased in all retrobulbar arteries, suggesting that after local diffusion, bevacizumab exerts a short-term regional effect. Bevacizumab might therefore induce hypoperfusion of the whole eye, which may correspond to a vascular side-effect. [source] Intrinsic vasomotricity and adrenergic effects in a model of isolated rabbit eyeACTA OPHTHALMOLOGICA, Issue 4 2009Esmeralda Delgado Abstract. Purpose:, We aimed to investigate the responsiveness of the ocular arteries to adrenergic drugs in a model of perfused isolated rabbit eye. Methods:, Rabbit external ophthalmic arteries (n = 15) in a head-mounted preparation were cannulated and the retinal and uveal vasculature perfused at a constant flow with warmed tyrode. The three-way polypropylene catheter was further connected to a pressure transducer and intraluminal pressure was taken as a measure of vascular resistance. Effects of intra-arterial injections of phenylephrine (group A, n = 5), prazosin (group B, n = 5) and phentolamine (group C, n = 5) on the recorded pressure were obtained. Student's paired- t test and one-way analysis of variance were used for statistical analysis (p < 0.05). Results:, Intrinsic vasomotricity was observed in all preparations prior to any drug administration. Phenylephrine produced an increase in total vascular resistance. Intrinsic vasomotricity became more evident, showing a lower frequency but higher amplitude of oscillations. Evoked vasomotor responses with phenylephrine (250 ,g/ml) were inhibited by intra-arterial administration of the selective ,1 -adrenergic antagonist, prazosin (0.5 mg/ml), as well as the non-selective ,-adrenergic antagonist phentolamine (6 mg/ml). Conclusions:, Rabbit external ophthalmic arteries showed spontaneous contractions under constant perfusion. Phenylephrine elicited a vasoconstrictor response that was inhibited by adrenergic antagonists. In addition, the intrinsic vasomotricity was enhanced by phenylephrine and blocked by adrenergic antagonists. These results show that under in vitro perfusion the territory presents similar responses to adrenergic drugs to those observed in in vivo models and also provides evidence of myogenic autoregulatory properties in the rabbit ophthalmic artery and/or choroid. [source] Comparison of orbital colour Doppler findings with computed tomography angiographyCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2000Bill Gillies ABSTRACT Colour Doppler imaging (CDI) of orbital vessels is non- invasive but may be fallacious, while computed tomography (CT) angiography displays a visual outline of orbital vessels. We compared clinical findings of the two methods in 33 patients with a wide variety of clinical conditions. It was not possible to visualize the central retinal arteries with CT angiography, but it was possible to show the intracranial carotid, which CDI could not. Changes in the ophthalmic arteries on CDI usually showed changes in calibre on CT angiography. Patients with unexplained or gross visual loss often showed marked abnormalities on CT scanning, not entirely consistent with the clinical picture. Several patients showed marked ectasia of the intracranial carotid along with variable clinical findings. Findings on CT angiography complement and augment those on CDI, and are likely to be more clinically valuable in the future. [source] Effects of intravitreal bevacizumab (Avastin®) therapy on retrobulbar blood flow parameters in patients with neovascular age-related macular degenerationJOURNAL OF CLINICAL ULTRASOUND, Issue 2 2010Ahmet Mete MD Abstract Background. To investigate the effects of intravitreal bevacizumab on retrobulbar circulation in patients with neovascular age-related macular degeneration (AMD). Method. Thirty patients with neovascular age-related macular degeneration were assessed prospectively by both color Doppler imaging and fundus fluorescein angiography. Spectral Doppler analysis allowed the measurement of the maximum velocity (Vmax) and minimum velocity (Vmin) of the central retinal vein (CRV), and peak systolic (PSV), end-diastolic (EDV) velocities of blood flows, and pulsatility index (PI) and resistance index (RI) values in the central retinal artery (CRA), nasal and temporal posterior ciliary arteries (NPCA, TPCA), and ophthalmic artery (OA). The t test for paired samples was used to compare retrobulbar blood flow values before and after intravitreal bevacizumab injection. Result. PSV and EDV of the NPCA and PSV of the TPCA were significantly decreased after intravitreal bevacizumab injection (p < 0.05). There was no statistically significant difference in the other parameters. Conclusion. Our results suggest that intravitreal bevacizumab therapy has a measurable effect on retrobulbar blood flow. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound 2010 [source] Orbital blood flow velocities in patients with rheumatoid arthritisJOURNAL OF CLINICAL ULTRASOUND, Issue 7 2007Besir Erdogmus MD Abstract Purpose. To assess orbital blood flow changes in patients with rheumatoid arthritis using Doppler sonography. Patients and Methods. The study comprised 35 patients who were diagnosed with RA and were treated at the Department of Physical Therapy and Rehabilitation at Duzce Medical School. A control group consisted of 35 healthy volunteers. Color Doppler imaging was used to measure peak systolic velocity (PSV) and end diastolic velocity (EDV), from which the resistance index (RI) was calculated in the ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary arteries (PCAs). Results. In the OA, PSV, EDV, and RI were, respectively, 36.7 ± 0.6 cm/sec, 9.7 ± 0.2 cm/sec, and 0.73 in the control group versus 34.7 ± 3.0 cm/sec, 9.1 ± 1.1 cm/sec, and 0.74 in the patient group. In the CRA, they were, respectively, 11.8 ± 1.7 cm/sec, 3.6 ± 0.7 cm/sec, and 0.66 in the control group versus 11.1 ± 1.7 cm/sec, 3.4 ± 0.7 cm/sec, and 0.68 in the patient group. In the PCAs, they were, respectively, 13.2 ± 1.2 cm/sec, 4.7 ± 0.6 cm/sec, and 0.65 in the control group versus 12.4 ± 1.2 cm/sec, 4.2 ± 0.6 cm/sec, and 0.66 in the PCAs. PSV, EDV, and RI of the PCAs and OA and RI of the CRA were significantly different between patients and controls, whereas there was no difference in the serum levels of glucose, triglyceride, low-density lipoprotein cholesterol, and total cholesterol. In the patient group, there was a significant correlation between orbital blood flow and duration of disease. Conclusion. Ocular blood flow appears to be slightly lower in RA patients than in healthy controls, suggesting that RA is a systemic inflammatory disease that may also involve ocular vessels. © 2007 Wiley Periodicals, Inc. J Clin Ultrasound, 2007 [source] Doppler measurement of blood flow velocities in extraocular orbital vessels in patients with obstructive sleep apnea syndromeJOURNAL OF CLINICAL ULTRASOUND, Issue 5 2003C. 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] Observer experience improves reproducibility of color doppler sonography of orbital blood vesselsJOURNAL OF CLINICAL ULTRASOUND, Issue 6 2002János 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] The morphometric analysis of the central retinal arteryOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 4 2005Necdet Kocabiyik Abstract In this study, we aimed to investigate some features of the central retinal artery (CRA), which supplies the internal aspect of the retina. The CRA is the main vessel supplying blood to the retina. The origin, course and penetration point of the optic nerve by the CRA were studied in 30 human orbits. We compared the right sides to the left sides on the basis of gender in order to statistically analyse the relation between them. The CRA arose directly from the ophthalmic artery in 28 specimens. In two specimens, however, it arose in common with the medial posterior ciliary artery. When we observed the penetration point (site) of the CRA into the optic nerve, in 28 of 30 (93.3%) cases, the artery entered the nerve from the lower medial aspect and in two (6.7%) cases from the upper lateral aspect. The CRA penetrated the optic nerve between 6.4 and 15.2 mm behind the eyeball and reached the eyeball through the centre of the optic nerve. Because of the small diameter of the artery, it has a high risk of getting damaged during a surgical approach to the orbit. Therefore the anatomical relationships of this artery must be well known. [source] Access of autonomic nerves through the optic canal, and their orbital distribution in manTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 1 2003Gordon L. Ruskell Abstract The notion that autonomic nerves from the internal carotid plexus are transmitted to the orbit with the ophthalmic artery through the optic canal has been variously assumed, disregarded, or denied, but never demonstrated. The objective of this study was to examine the contents of the canal, identify any autonomic nerves, and follow their passage within the orbit. The soft tissues of the optic canal, and the apical tissues of the orbit were removed and examined histologically using 10 cadaver preparations. Additionally, tissues from an orbital exenteration and 10 ocular enucleation or donor specimens were prepared. Some of the latter material was examined with an electron microscope. Numerous autonomic nerves (four to 25, ranging in diameter from 23 to 130 ,m) entered the orbit from the internal carotid plexus in the periosteum of the optic canal, the optic nerve dura mater, or the adventitia of the ophthalmic artery. In the orbit they advanced in the loose connective tissue covering the optic nerve dura and joined ciliary nerves close to the eye or entered the eye directly. None were observed to penetrate the dura, apart from a nerve accompanying the central retinal artery. Others were distributed with the ophthalmic artery and its branches. It is concluded that the optic canal is a regular, and often major, route for autonomic nerve distribution to the eye and orbit. Anat Rec Part A 275A:973,978, 2003. © 2003 Wiley-Liss, Inc. [source] 4364: Direct intra-arterial (ophthalmic artery) chemotherapy with melphalan for advanced intraocular retinoblastoma: the Italian experienceACTA OPHTHALMOLOGICA, Issue 2010T HADJISTILIANOU Purpose To report the preliminary results of the conservative treatment of advanced retinoblastoma (Stage Va e Vb) obtained with the melphalan protocol (direct intraarterial-ophthalmic artery infusion ). Methods 33 children (35 eyes) with advanced retinoblastoma who were eligible for enucleation were entered in phase two of one center open study-approved protocol of ophthalmic artery infusion of Melphalan to avoid enucleation (Italian Melphalan protocol, approved by the Ethic Commettee , University Hospital of Siena). Two cases have been treated bilaterally. 15 eyes were first diagnosis and 18 were relapses following chemo and/or radiotherapy. In two cases has not been possible to conclude the procedure due to haemodynamic problems. Results The ophthalmic artery was successfully cannulated in 35 eyes (total, 121 procedures). In 2 attempts was impossible to successfully conclude the procedure due to hemodynamic problems. Cannulation of the ophthalmic artery was performed by a femoral artery approach using microcatheters (magic 1.5) while the children were under general anesthesia and anticoagulated. Melphalan was infused into the artery over a 30-minute period (dose of 3-7 mg according to the age and size of the globe). Local and systemic toxicity have been evaluated and documented. Conclusion 33 children (35 eyes) with advanced retinoblastoma (Stage Va and Vb Reese classification) were eligible for the Melphalan Italian Protocol. The 78.7% of treated eyes is in complete remission. Superselective chemotherapy delivered through the ophthalmic artery can avoid enucleation, primary radiation or abuse of systemic chemotherapy. [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 glaucomaACTA OPHTHALMOLOGICA, Issue 5 2010Antonio 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] Effects of moxaverine on ocular blood flow in patients with age-related macular degeneration, patients with primary open angle glaucoma and in healthy controlsACTA OPHTHALMOLOGICA, Issue 2009B PEMP Purpose Several common eye diseases including age-related macular degeneration (AMD) and primary open angle glaucoma (POAG) are associated with ocular perfusion abnormalities. Moxaverine has been shown to increase ocular blood flow in young, healthy volunteers after intravenous administration. The present study investigated whether moxaverine alters ocular blood flow in elderly patients with AMD or POAG and in healthy control subjects. Methods 20 patients with AMD, 20 patients with POAG and 20 age-matched healthy subjects were included in this trial. 150 mg moxaverine (Ursapharm, Saarbrücken, Germany) was administered intravenously over 30 minutes. Systemic haemodynamics, retinal vessel diameters, choroidal, optic nerve head and retrobulbar blood flow were measured before and up to 90 minutes after drug administration. Results Administration of moxaverine increased choroidal blood flow by 8.7 ± 21.8% (p=0.012) and optic nerve head blood flow by 12.9 ± 33.3% (p=0.021). Additionally, an increase in the mean flow velocities of posterior ciliary arteries (24.8 ± 34.7%, p<0.001) and in the ophthalmic artery (23.3 ± 33.5%, p<0.001) was found after administration of moxaverine. However, no differences were found between the 3 study groups. No significant change of retinal vessel diameters was observed. Conclusion The present study indicates an increase of ocular blood flow after systemic administration of a single dose of moxaverine in patients with POAG, patients with AMD and in age-matched healthy controls. Further studies are needed to investigate possible beneficial effects after long-term treatment in patients with ocular diseases associated with hypoperfusion. [source] Intrinsic vasomotricity and adrenergic effects in a model of isolated rabbit eyeACTA OPHTHALMOLOGICA, Issue 4 2009Esmeralda Delgado Abstract. Purpose:, We aimed to investigate the responsiveness of the ocular arteries to adrenergic drugs in a model of perfused isolated rabbit eye. Methods:, Rabbit external ophthalmic arteries (n = 15) in a head-mounted preparation were cannulated and the retinal and uveal vasculature perfused at a constant flow with warmed tyrode. The three-way polypropylene catheter was further connected to a pressure transducer and intraluminal pressure was taken as a measure of vascular resistance. Effects of intra-arterial injections of phenylephrine (group A, n = 5), prazosin (group B, n = 5) and phentolamine (group C, n = 5) on the recorded pressure were obtained. Student's paired- t test and one-way analysis of variance were used for statistical analysis (p < 0.05). Results:, Intrinsic vasomotricity was observed in all preparations prior to any drug administration. Phenylephrine produced an increase in total vascular resistance. Intrinsic vasomotricity became more evident, showing a lower frequency but higher amplitude of oscillations. Evoked vasomotor responses with phenylephrine (250 ,g/ml) were inhibited by intra-arterial administration of the selective ,1 -adrenergic antagonist, prazosin (0.5 mg/ml), as well as the non-selective ,-adrenergic antagonist phentolamine (6 mg/ml). Conclusions:, Rabbit external ophthalmic arteries showed spontaneous contractions under constant perfusion. Phenylephrine elicited a vasoconstrictor response that was inhibited by adrenergic antagonists. In addition, the intrinsic vasomotricity was enhanced by phenylephrine and blocked by adrenergic antagonists. These results show that under in vitro perfusion the territory presents similar responses to adrenergic drugs to those observed in in vivo models and also provides evidence of myogenic autoregulatory properties in the rabbit ophthalmic artery and/or choroid. [source] Colour Doppler imaging evaluation of blood flow parameters in the ophthalmic artery in acute and chronic phases of optic neuritis in multiple sclerosisACTA OPHTHALMOLOGICA, Issue 1 2009Pavel Hradílek Abstract. Purpose:, Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS). It is caused by the immune-mediated inflammation of the optic nerve. Some vascular factors that may influence blood flow in the ophthalmic artery (OA) have also been suggested as factors in the pathogenesis of ON. The purpose of our study was to evaluate blood flow velocities and resistance (RI) and pulsatile (PI) indices in the OA in both orbits in patients in the acute and chronic phases of unilateral ON and to compare these with equivalent findings in healthy control subjects. Methods:, Orbital colour Doppler imaging (CDI) was performed in 40 consecutive MS patients during acute unilateral ON prior to corticosteroid treatment. Optic neuritis was diagnosed on the basis of clinical presentation and facultative assessment of visual evoked potentials (VEPs). The peak systolic (PSV) and end-diastolic (EDV) velocities and RI and PI were measured in the OA in both eyes. We compared results from affected and unaffected orbits using the paired t -test. The same measurements were performed in 114 MS patients with a history of acute unilateral ON that occurred > 1 year prior to ultrasound examination. We also measured the same parameters in the middle cerebral arteries (MCAs) on both sides in all subjects in both groups. The same measurements were obtained in healthy controls. Results:, The PSV (p < 0.0001), RI (p < 0.0001) and PI (p < 0.0001) in the OA in the eye affected with acute ON were significantly higher than in the unaffected eye. There was no difference in EDV in the OA between affected and unaffected eyes (p > 0.05) in the group with acute ON. We did not observe any significant differences between eyes in either blood flow velocities or the RI or PI (p > 0.05) in the group in the chronic phase of ON or in the control group. All the parameters in the MCAs on both sides were normal in both the acute and chronic groups, as well as in the control group. Conclusions:, Pathophysiological changes during acute unilateral ON influence orbital haemodynamics, as is indicated by increased PSV, RI and PI in the OA in eyes affected with ON. However, these changes do not persist over longer periods. [source] Colour Doppler examination of early and late orbital haemodynamic changes in eyes with eyelid oedema due to blunt traumaACTA OPHTHALMOLOGICA, Issue 2 2006Mehmet 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] Ophthalmic artery blood flow velocity changes in diabetic patients as a manifestation of macroangiopathyACTA OPHTHALMOLOGICA, Issue 2 2000Masanori Ino-ue ABSTRACT. Purpose: The hemodynamic characteristics of ophthalmic artery (OA) blood flow velocity in diabetic patients with ocular involvement were evaluated. Methods: Changes in OA blood flow of eyes with background diabetic retinopathy (BDR), proliferative retinopathy (PDR) and ocular ischemic syndrome (OIS) were ananalyzed by Color Doppler imaging. Results: Patients with BDR and PDR had significantly lower diastolic and mean blood flow velocities and higher pulsatility indices compared to controls. Diabetic patients with OIS had significantly lower systolic, diastolic and mean anterograde OA blood flow velocities than the controls. Pulsatility indices were higher in anterograde OA blood flow measurements compared to controls. Systolic blood flow velocities in rubeotic eyes with OIS were significantly lower than in rubeotic eyes with PDR. Conclusion: OA blood flow measurements by color doppler imaging may detect macroangiopathies in diabetic patients as manifested by carotid atheromas and arterio- and arterosclerosis of the OA and its branches. [source] Paraclinoid and cavernous sinus regions: Measurement of critical structures relevant for surgical procedureCLINICAL ANATOMY, Issue 1 2005Frederic Collignon Abstract Determination of the safest distance the falciform ligament can be incised from its origin to the orbital apex. Measurement of the distance between the oculomotor foramen and the IV nerve in the lateral wall of the cavernous sinus. Evaluation of the optic strut as an accurate landmark between the intradural (subarachnoid) and extradural segment of the internal carotid artery (ICA). Ten fixed human cadaver heads were examined for a total of 20 sides. A frontotemporal craniotomy, an orbito-optic osteotomy, and extradural anterior clinoidectomy were carried out followed by opening the falciform ligament, circumferentially releasing the distal dural ring and dissection of the lateral wall of the cavernous sinus under the operating microscope. We measured: 1) the distance between the entry of the III nerve and the point where the IV nerve crosses over it into the cavernous sinus; 2) the distance the falciform ligament can be incised along the optic nerve laterally until the IV nerve is encountered at the orbital apex; 3) the distance between the optic strut and the lateral part of the distal dural ring; and 4) the distance between the optic strut and the ophthalmic artery. All measurements were made in millimeters, using small calipers. The distance between the optic strut and the lateral part of the distal dural ring ranges from 3,7.5 mm (mean = 5.47 mm). In all our specimens, the ophthalmic artery was found distally from the optic strut in the intradural space at a distance ranging from 0.5,7 mm (mean = 3.35 mm). The distance between the entry of the third nerve and the IV nerve into the cavernous sinus ranged from 7,15 mm (mean = 10.9 mm). The distance between the origin of the falciform ligament and the IV nerve at the level of the orbital apex ranged from 9,15 mm (mean = 10.75 mm). The falciform ligament and the optic sheath should not be opened longer than 9 mm along the lateral optic nerve or injury to the IV nerve can occur. Starting at the oculomotor foramen, the opening of the cavernous sinus should be limited to 7 mm to avoid injuring the IV nerve. Finally, the optic strut can be a reliable bony landmark that separates the subarachnoid space and extradural compartments along the anterior and medial ICA. Clin. Anat. 18:3,9, 2005. © 2004 Wiley-Liss, Inc. [source] | |||||||||||||