917 resultados para CAROTID-SINUS NERVE


Relevância:

30.00% 30.00%

Publicador:

Resumo:

BACKGROUND: The development of a microcomputer-based device permits quick, simple, and noninvasive quantification of the respiratory sinus arrhythmia (RSA) during quiet breathing. METHODS AND RESULTS: We prospectively and serially measured the radionuclide left ventricular ejection fraction and the RSA amplitude in 34 cancer patients receiving up to nine monthly bolus treatments with doxorubicin hydrochloride (60 mg/m2). Of the eight patients who ultimately developed symptomatic doxorubicin-induced congestive heart failure, seven (87.5%) demonstrated a significant decline in RSA amplitude; five of 26 subjects without clinical symptoms of cardiotoxicity (19.2%) showed a similar RSA amplitude decline. On average, significant RSA amplitude decline occurred 3 months before the last planned doxorubicin dose in patients destined to develop clinical congestive heart failure. CONCLUSION: Overall, RSA amplitude abnormality proved to be a more specific predictor of clinically significant congestive heart failure than did serial resting radionuclide ejection fractions.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

To assess 3-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT) techniques to see whether doses to critical structures could be reduced while maintaining planning target volume (PTV) coverage in patients receiving conventional radiotherapy (RT) for carcinoma of the maxillary sinus because of the risk of radiation-induced complications, particularly visual loss. Six patients who had recently received conventional RT for carcinoma of the maxillary sinus were studied. Conventional RT, 3D-CRT, and step-and-shoot IMRT plans were prepared using the same 2-field arrangement. The effect of reducing the number of segments in the IMRT beams was investigated. 3D-CRT and IMRT reduced the brain and ipsilateral parotid gland doses compared with the conventional plans. IMRT reduced doses to both optic nerves; for the contralateral optic nerve, 15-segment IMRT plans delivered an average maximal dose of 56.4 Gy (range 53.9–59.3) compared with 65.7 Gy (range 65.3–65.9) and 64.2 Gy (range 61.4–65.6) for conventional RT and 3D-CRT, respectively. IMRT also gave improved PTV homogeneity and improved coverage, with an average of 8.5% (range 7.0–11.7%) of the volume receiving

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Background Along the internal carotid artery (ICA), atherosclerotic plaques are often located in its cavernous sinus (parasellar) segments (pICA). Studies indicate that the incidence of pre-atherosclerotic lesions is linked with the complexity of the pICA; however, the pICA shape was never objectively characterized. Our study aims at providing objective mathematical characterizations of the pICA shape. Methods and results Three-dimensional (3D) computer models, reconstructed from contrast enhanced computed tomography (CT) data of 30 randomly selected patients (60 pICAs) were analyzed with modern visualization software and new mathematical algorithms. As objective measures for the pICA shape complexity, we provide calculations of curvature energy, torsion energy, and total complexity of 3D skeletons of the pICA lumen. We further measured the posterior knee of the so-called ""carotid siphon"" with a virtual goniometer and performed correlations between the objective mathematical calculations and the subjective angle measurements. Conclusions Firstly, our study provides mathematical characterizations of the pICA shape, which can serve as objective reference data for analyzing connections between pICA shape complexity and vascular diseases. Secondly, we provide an objective method for creating Such data. Thirdly, we evaluate the usefulness of subjective goniometric measurements of the angle of the posterior knee of the carotid siphon.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Inside the `cavernous sinus` or `parasellar region` the human internal carotid artery takes the shape of a siphon that is twisted and torqued in three dimensions and surrounded by a network of veins. The parasellar section of the internal carotid artery is of broad biological and medical interest, as its peculiar shape is associated with temperature regulation in the brain and correlated with the occurrence of vascular pathologies. The present study aims to provide anatomical descriptions and objective mathematical characterizations of the shape of the parasellar section of the internal carotid artery in human infants and its modifications during ontogeny. Three-dimensional (3D) computer models of the parasellar section of the internal carotid artery of infants were generated with a state-of-the-art 3D reconstruction method and analysed using both traditional morphometric methods and novel mathematical algorithms. We show that four constant, demarcated bends can be described along the infant parasellar section of the internal carotid artery, and we provide measurements of their angles. We further provide calculations of the curvature and torsion energy, and the total complexity of the 3D skeleton of the parasellar section of the internal carotid artery, and compare the complexity of this in infants and adults. Finally, we examine the relationship between shape parameters of the parasellar section of the internal carotid artery in infants, and the occurrence of intima cushions, and evaluate the reliability of subjective angle measurements for characterizing the complexity of the parasellar section of the internal carotid artery in infants. The results can serve as objective reference data for comparative studies and for medical imaging diagnostics. They also form the basis for a new hypothesis that explains the mechanisms responsible for the ontogenetic transformation in the shape of the parasellar section of the internal carotid artery.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Introduction: Impacted knife injuries in the maxillofacial region are rare and infrequently reported. In cases of injury involving orbit or eye, these reports are even rarer. Discussion: Damage to the orbital contents may result in a rupture of the globe, extraocular muscle injury, lacrimal gland damage, and others. Orbital foreign bodies are not only difficult to detect, and clinical features vary according to its size, characteristics, shape, penetrating method, and site. In this report, a case of abducens nerve palsy after orbitoethmoidal knife injury is presented. © 2010 Springer-Verlag.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Relevância:

30.00% 30.00%

Publicador:

Resumo:

BACKGROUND AND PURPOSE: Isolated Horner syndrome without associated cranial nerve palsies or ischemic symptoms is an important presentation of spontaneous internal carotid artery dissection (sICAD). Ultrasound is often used as a screening method in these patients because cervical MRI is not always available on an emergency basis. Current knowledge on ultrasound findings in patients with sICAD presenting with isolated Horner syndrome is limited. METHODS: Patients were recruited from prospective cervical artery dissection databases of 3 tertiary care centers. Diagnosis of sICAD was confirmed by cervical MRI and MR angiography or digital subtraction angiography in all patients. Data on Doppler sonography and color duplex sonography examinations performed within 30 days of symptom onset were analyzed. RESULTS: We identified 88 patients with Horner syndrome as the only sign of sICAD. Initial ultrasound examination was performed in 72 patients after a mean time interval from symptom onset to examination of 11 (SD 8) days. The overall frequency of false-negative ultrasound findings was 31% (22 of 72 patients). It showed stenosis >or=80% or occlusion in 34 (47%) patients, and stenosis

Relevância:

30.00% 30.00%

Publicador:

Resumo:

BACKGROUND: Recent dramatic changes in surgical training resulting from working-hour regulations may lead to lack of competence. Traditionally, carotid surgery has been the domain of specialists. This study was designed to compare the outcome of carotid endarterectomy performed by vascular surgical trainees versus vascular surgeon (VS). METHODS: A retrospective study of 1,379 consecutive patients who underwent carotid endarterectomy as the sole procedure under local or general anesthesia (from 1995-2004) was performed. All patients were admitted to the intensive care unit for 24 hours. Trainees performed 475 (34.5%) and vascular specialists performed 904 (65.5%) operations. RESULTS: Patient characteristics with regard to preoperative neurological status were similar. Trainees operated on 61.4% symptomatic patients and VS on 56.8% (P = 0.09). Shunt use did not differ (16% trainee vs. 17.8% VS). Clamping time and total operating time were longer among trainees (41.9 vs. 33.5 min, P < 0.001; and 121.2 vs. 101.8 min, P < 0.001, respectively). Postoperative stroke and death rates (3.2% vs. 3.1% and 0.4% vs. 0.9%, respectively) did not differ. Peripheral nerve complications were more common among trainees (12.2% vs. 6.5%; P < 0.0001); 99.6% of these nerve injuries had resolved at 3 months' follow-up. CONCLUSIONS: Carotid endarterectomy can be performed safely by a trainee vascular surgeon when assisted and supervised by a specialist vascular surgeon.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

BACKGROUND: No randomized study has yet compared efficacy and safety of aspirin and anticoagulants in patients with spontaneous dissection of the cervical carotid artery (sICAD). METHODS: Prospectively collected data from 298 consecutive patients with sICAD (56% men; mean age 46 +/- 10 years) treated with anticoagulants alone (n = 202) or aspirin alone (n = 96) were retrospectively analyzed. Admission diagnosis was ischemic stroke in 165, TIA in 37, retinal ischemia in 8, and local symptoms and signs (headache, neck pain, Horner syndrome, cranial nerve palsy) in 80 patients, while 8 patients were asymptomatic. Clinical follow-up was obtained after 3 months by neurologic examination (97% of patients) or structured telephone interview. Outcome measures were 1) new cerebral ischemic events, defined as ischemic stroke, TIA, or retinal ischemia, 2) symptomatic intracranial hemorrhage, and 3) major extracranial bleeding. RESULTS: During follow-up, ischemic events were rare (ischemic stroke, 0.3%; TIA, 3.4%; retinal ischemia, 1%); their frequency did not significantly differ between patients treated with anticoagulants (5.9%) and those treated with aspirin (2.1%). The same was true for hemorrhagic adverse events (anticoagulants, 2%; aspirin, 1%). New ischemic events were significantly more frequent in patients with ischemic events at onset (6.2%) than in patients with local symptoms or asymptomatic patients (1.1%). CONCLUSIONS: Within the limitations of a nonrandomized study, our data suggest that frequency of new cerebral and retinal ischemic events in patients with spontaneous dissection of the cervical carotid artery is low and probably independent of the type of antithrombotic treatment (aspirin or anticoagulants).

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The Barostim neo ™ system is a novel implantable device that activates the carotid baroreflex. It decreases the sympathetic activity and inhibits the renin system, which results in reduced blood pressure and heart rate. In patients with resistant hypertension, electrically activation of the baroreflex leads to an average decrease in systolic blood pressure of 38, 36, 40 and 53 mmHg at 1, 2, 3 and 4 years, respectively. Additionally, cardiac remodelling with reduced left ventricular mass and posterior wall thickness has been observed in long-term studies. In a limited number of patients with heart failure, baroreflex activation therapy leads to a decrease in muscle sympathetic nerve activity and to improved quality of life and functional capacities. The implantation procedure is safe and associated with risks comparable with those of other active implantable devices. Barostim neo is currently available in several European countries.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

The anterior superior alveolar nerve (ASAN) is a branch of the infraorbital nerve. Only few studies have morphometrically evaluated the course of the ASAN. Midfacial segments of ten hemisectioned fresh adult cadaver heads were dissected to uncover the anterior wall of the maxilla. Specimens were subsequently decalcified and the bone overlying the ASAN was removed under a microscope to expose the ASAN. Its branching pattern from the infraorbital nerve was recorded, and the course of the ASAN within the anterior wall of the maxillary sinus was morphometrically assessed measuring distances to predefined landmarks using a digital caliper. A distinct ASAN was observed in all specimens. It arose lateral (six cases) or inferior (four cases) from the infraorbital nerve. The point of origin was located at a mean distance of 12.2 ± 5.79 mm posterior to the infraorbital foramen. The ASAN was located on average 2.8 ± 5.13 mm lateral to the infraorbital foramen. After coursing medially, the ASAN ran inferior to the foramen at a mean distance of 5.5 ± 3.07 mm. When approaching the nasal aperture, the loop of the ASAN was on average 13.6 ± 3.07 mm above the nasal floor. The horizontal mean distance from the ASAN to the nasal aperture was 4.3 ± 2.74 mm halfway down from the loop, and 3.3 ± 2.60 mm at the floor of the nose, respectively. In conclusion, the present study evaluated the course of the ASAN relative to the infraorbital foramen and nasal aperture. This information is helpful to avoid damage to this anatomical structure during interventions in the infraobrital region of the maxilla. Further, knowledge of the course of the ASAN and of its bony correlate (canalis sinuosus) may be valuable in interpreting anesthetic or radiologic findings in the anterior maxilla.

Relevância:

30.00% 30.00%

Publicador:

Resumo:

Objective: Laryngeal and tongue function was assessed in 28 patients to evaluate the presence, nature, and resolution of superior recurrent laryngeal and hypoglossal nerve damage resulting from standard open primary carotid endarterectomy (CEA). Methods. The laryngeal and tongue function in 28 patients who underwent CEA were examined prospectively with various physiologic (Aerophone II, laryngograph, tongue transducer), acoustic (Multi-Dimensional Voice Program), and perceptual speech assessments. Measures were obtained from all participants preoperatively, and at 2 weeks and at 3 months postoperatively. Results. The perceptual speech assessment indicated that the vocal quality of roughness was significantly more apparent at the 2-week postoperative assessment than preoperatively. However, by the 3-month postoperative assessment these values had returned to near preoperative levels, with no significant difference detected between preoperative and 3-month postoperative levels or between 2-week and 3-month postoperative levels. Both the instrumental assessments of laryngeal function and the acoustic assessment of vocal quality failed to identify any significant difference on any measure across the three assessment periods. Similarly, no significant impairment in tongue strength, endurance, or rate of repetitive tongue movements was detected at instrumental assessment of tongue function. Conclusions: No permanent changes to vocal or tongue function occurred in this group of participants after primary CEA. The lack of any significant long-term laryngeal or tongue dysfunction in this group suggests that the standard open CEA procedure is not associated with high rates of superior recurrent and hypoglossal nerve dysfunction, as previously believed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Purpose: To determine the subbasal nerve density and tortuosity at 5 corneal locations and to investigate whether these microstructural observations correlate with corneal sensitivity. Method: Sixty eyes of 60 normal human subjects were recruited into 1 of 3 age groups, group 1: aged ,35 years, group 2: aged 35–50 years, and group 3: aged .50 years. All eyes were examined using slit-lamp biomicroscopy, noncontact corneal esthesiometry, and slit scanning in vivo confocal microscopy. Results: The mean subbasal nerve density and the mean corneal sensitivity were greatest centrally (14,731 6 6056 mm/mm2 and 0.38 6 0.21 millibars, respectively) and lowest in the nasal mid periphery (7850 6 4947 mm/mm2 and 0.49 6 0.25 millibars, respectively). The mean subbasal nerve tortuosity coefficient was greatest in the temporal mid periphery (27.3 6 6.4) and lowest in the superior mid periphery (19.3 6 14.1). There was no significant difference in mean total subbasal nerve density between age groups. However, corneal sensation (P = 0.001) and subbasal nerve tortuosity (P = 0.004) demonstrated significant differences between age groups. Subbasal nerve density only showed significant correlations with corneal sensitivity threshold in the temporal cornea and with subbasal nerve tortuosity in the inferior and nasal cornea. However, these correlations were weak. Conclusions: This study quantitatively analyzes living human corneal nerve structure and an aspect of nerve function. There is no strong correlation between subbasal nerve density and corneal sensation. This study provides useful baseline data for the normal living human cornea at central and mid-peripheral locations