RESUMEN
OBJECTIVES: The geometry of carotid bifurcation is a crucial contributing factor to the localization of atherosclerotic lesions. Currently, studies on carotid bifurcation geometry are limited to the region near to bifurcation. This study aimed to determine the influence of carotid bifurcation geometry on the blood flow using numerical simulations considering magnitude of haemodynamic parameters in the extended regions of carotid artery. METHODS: In the present study, haemodynamic analysis is carried out using the non-Newtonian viscosity model for patient-specific geometries consisting of both Left and Right carotid arteries. A 3D patient-specific geometric model is generated using MIMICS, and a numerical model is created using ANSYS. RESULTS: The results obtained from patient-specific cases are compared. The influence of geometric features such as lumen diameter, bifurcation angle, and tortuosity on the haemodynamics parameters such as velocity, WSS, pressure, Oscillatory Shear Index (OSI), and Time-Averaged Wall Shear Stress (TAWSS) are compared. CONCLUSION: The results demonstrate significant changes in the flow regime due to the geometric shape of the carotid artery. It is observed that the lower value of TAWSS occurs near the bifurcation region and carotid bulb region. In addition, the higher value of the (OSI) is observed in the Internal Carotid Artery (ICA) and the tortuous carotid artery region. However, it is also observed that apart from the bifurcation angle, other factors, such as tortuosity and area ratio, play a significant role in the flow dynamics of the carotid artery.
Asunto(s)
Arterias Carótidas , Hemodinámica , Humanos , Arterias Carótidas/diagnóstico por imagen , Arteria Carótida Interna/diagnóstico por imagen , Viscosidad , Velocidad del Flujo Sanguíneo/fisiología , Estrés MecánicoRESUMEN
Although insertion of chest drain tubes is a common medical practice, there are risks associated with this procedure, especially when inexperienced physicians perform it. Wrong insertion of the tube has been known to cause morbidity and occasional mortality. We report a case where the left ventricle was accidentally punctured leading to near-exsanguination. This report is to highlight the need for experienced physicians to supervise the procedure and train the younger physician in the safe performance of the procedure.
Asunto(s)
Tubos Torácicos/efectos adversos , Drenaje/instrumentación , Ventrículos Cardíacos/lesiones , Adulto , Drenaje/efectos adversos , Drenaje/métodos , Extravasación de Materiales Terapéuticos y Diagnósticos , Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/cirugía , Humanos , Masculino , Errores Médicos , Tomografía Computarizada por Rayos XRESUMEN
Gravity associated with postural changes has a strong bearing on haemodynamics of blood flow in arteries. Its effect on stenosed cases has not been widely investigated. In the present study, variation observed in blood flow during postural changes is investigated for different conditions like standing, sleeping and head-down position. A fluid structure interaction study is carried out for idealized normal and 75% eccentric and concentric stenosed common carotid normal artery. The results clearly indicate the effects of altered gravity on flow conditions. It was found to be very significant during head-down position and demonstrated very high arterial blood pressure in stenosed common carotid when compared with normal carotid.
Asunto(s)
Arteria Carótida Común/fisiología , Estenosis Carotídea/fisiopatología , Modelos Cardiovasculares , Postura/fisiología , Algoritmos , Velocidad del Flujo Sanguíneo/fisiología , Presión Sanguínea/fisiología , Hemorreología , HumanosRESUMEN
We report the case of a 49-year-old woman who presented with breathlessness on exertion and iron deficiency anaemia. Evaluation revealed a large mass in the right lung which on further investigation was determined to be a pulmonary arteriovenous malformation (PAVM) with a large aneurysmal sac. The patient subsequently underwent a lobectomy with an uneventful recovery. The pathophysiology of PAVM and its varied presentations are also discussed.
Asunto(s)
Fístula Arteriovenosa/diagnóstico , Fístula Arteriovenosa/cirugía , Angiografía , Fístula Arteriovenosa/complicaciones , Disnea/etiología , Femenino , Humanos , Persona de Mediana Edad , Arteria Pulmonar/anomalías , Arteria Pulmonar/cirugía , Venas Pulmonares/anomalías , Venas Pulmonares/cirugíaRESUMEN
A tracheo-innominate artery fistula is an uncommon but frequently fatal complication of tracheostomy. Rarely, it can also occur in laryngectomized patients. We report a post-laryngectomy, post-radiotherapy patient using a metal tracheostomy tube, who developed a tracheo-innominate artery fistula about two months after radiotherapy. To our knowledge this is only the second reported case in a laryngectomized patient. The computed tomography (CT) angiography findings helped confirm the diagnosis and the patient was successfully managed by surgical exploration and ligation of the innominate artery. Coagulase negative Staphylococcus aureus was cultured from a tracheal swab. The clinical features, CT angiography findings, management protocols and possible aetiological factors are discussed.