A Retrospective View of the Inherited Errors of the Thyroid System
Geraldo Medeiros-Neto in Inherited Disorders of the Thyroid System, 2019
On a summer morning in 1949, a call to the thyroid unit of the Massachussets General Hospital from the Ambulatory Pediatric Clinic requested help with a newly arrived patient. This proved to be a 16-year-old who was startling in appearance to say the very least. She sat in a crib screaming. She was obviously profoundly mentally deficient. A huge multilobed mass protruded from the space between her manubrium and chin. A careful examination disclosed every evidence of hypothyroidism, except that the region of the thyroid was warm to touch. A bruit and thrill confirmed the massive blood flow through the thyroid as did the huge vessels in relief below the surface of the skin of the anterior neck.
A CFD-FEA Coupling Study of Blood Flow in the Abnormal Cardiovascular System
Z. Yang in Multiphysics Modeling with Application to Biomedical Engineering, 2020
Blood flows in abnormal cardiovascular conditions and generates special sounds called “murmurs” or “bruits.” Disturbances in the blood flow caused by obstruction in the vessels generate the sounds. This study simulated blood flow in abnormal cardiovascular conditions in ANSYS with two couplings. The first FSI coupling occurred between the blood flow and the blood vessel, which was simplified as one-way coupling. The second FSI coupling was defined between the blood vessel and the tissues and considered as acoustic FSI. In a simulation, the first coupling was analyzed first, and its computational results were the loadings of the second coupling. The whole simulation was completed in ANSYS Fluent and ANSYS MAPDL. The computational results show that the peak value of the blood vessel with obstruction is much higher than that of the normal blood vessel, which validates that obstruction in the vessels generates the sounds.
Examination
Clive Handler, Gerry Coghlan, Nick Brown in Management of Cardiac Problems in Primary Care, 2018
Modern cardiac investigations provide important diagnostic and prognostic information, but they have not made physical examination redundant. Although time restraints on consultations may make it difficult to examine patients in primary care, physical examination remains an essential and diagnostically useful part of the consultation. The finding of hypertension, an irregular pulse, signs of heart failure, heart murmurs, a dilated pulsating abdominal aorta, leg swelling, absent leg pulses and femoral artery or carotid artery bruits provides important diagnostic information. Several cardiac conditions can be diagnosed in primary care after a systematic physical examination and attention to discriminatory signs. Patients without cardiac disease are grateful and reassured when told after the examination that they have nothing to worry about. Some physical signs have a low predictive accuracy for diagnosis because they are not specific or sensitive for cardiac disease. Non-specialists may find auscultation difficult and intimidating, but practice with a cardiologist will improve this important and productive clinical skill.
Carotid bruit for detection of hemodynamically significant carotid stenosis: the Northern Manhattan Study
Published in Neurological Research, 2009
Elizabeth V. Ratchford, Zhezhen Jin, Marco R. Di Tullio, Maya J. Salameh, Shunichi Homma, Robert Gan, Bernadette Boden-Albala, Ralph L. Sacco, Tatjana Rundek
Objective: The prevalence of carotid bruits and the utility of auscultation for predicting carotid stenosis are not well known. We aimed to establish the prevalence of carotid bruits and the diagnostic accuracy of auscultation for detection of hemodynamically significant carotid stenosis, using carotid duplex as the gold standard. Methods: The Northern Manhattan Study (NOMAS) is a prospective multiethnic community-based cohort designed to examine the incidence of stroke and other vascular events and the association between various vascular risk factors and subclinical atherosclerosis. Of the stroke-free cohort (n=3298), 686 were examined for carotid bruits and underwent carotid duplex. Main outcome measures included prevalence of carotid bruits and sensitivity, specificity, positive predictive value, negative predictive value and accuracy of auscultation for prediction of ipsilateral carotid stenosis. Results: Among 686 subjects with a mean age of 68.2 ± 9.4 years, the prevalence of ≥60% carotid stenosis as detected by ultrasound was 2.2% and the prevalence of carotid bruits was 4.1%. For detection of carotid stenosis, sensitivity of auscultation was 56%, specificity was 98%, positive predictive value was 25%, negative predictive value was 99% and overall accuracy was 97.5%. Discussion: In this ethnically diverse cohort, the prevalence of carotid bruits and hemodynamically significant carotid stenosis was low. Sensitivity and positive predictive value were also low, and the 44% false-negative rate suggests that auscultation is not sufficient to exclude carotid stenosis. While the presence of a bruit may still warrant further evaluation with carotid duplex, ultrasonography may be considered in high-risk asymptomatic patients, irrespective of findings on auscultation.
Clinical significance of carotid bruits: an innocent finding or a useful warning sign?
Published in Neurological Research, 2008
Kosmas I. Paraskevas, George Hamilton, Dimitri P. Mikhailidis
Objective: To elucidate the clinical relevance of carotid bruits. Methods: A search using PubMed was performed using the terms: 'carotid bruit', 'stroke', 'cerebrovascular symptoms', 'carotid artery stenosis' and 'carotid artery disease' in various combinations. The reference lists of the gathered reports were also considered. Results: Current evidence shows that a carotid bruit is a useful clinical sign with a high specificity (>90%) for the detection of carotid artery stenosis. The negative predictive value (>90%), as well as the accuracy (>90%), of this inexpensive method, are additional advantages. The low sensitivity (
Indirect measurement of aneurysm wall thickness using digital stethoscope
Published in Neurological Research, 2010
Liang-Der Jou, Michel E. Mawad
Objective: No existing in vivo technique can measure aneurysm wall thickness for evaluation of rupture risk. Intracranial aneurysms produce bruits at a special range of frequency that are highly influenced by the wall thickness. Understanding of the mechanism that generates bruits may allow us to learn aneurysm behavior non-invasively. Methods: A new theory was proposed to account for an interaction between an aneurysm and its parent vessel. Four patients with ophthalmic aneurysms were studied with a digital electronic stethoscope before and after endovascular treatment. Energy spectra of bruits were obtained from digital recording at both eyes. Change of energy spectra was used as an objective indication for aneurysm bruits. Additional four cases were obtained from a previous report. Results: Aneurysm bruits are affected by both aneurysm size and wall thickness. These sounds disappear after coil embolization and parent artery occlusion, but not by stenting. Both large and small aneurysms generate sounds at high frequency. Aneurysms at 6 mm produced very low frequency sound. Wall thickness decreases with aneurysm size, and the decrease is more pronounced at 8 mm. Conclusions: Interaction between an intracranial aneurysm and its parent vessel is important in interpretation of aneurysm bruits. An analysis of in vivo measurements shows a rapid decline in wall thickness for 8 mm aneurysms.