Interventional Radiology is a technique based medical specialty, using all available imaging modalities (fluoroscopy, ultrasound, computed tomography, magnetic resonance, angiography) for guidance of interventional techniques for diagnostic or therapeutic purposes. Actual, percutaneous transthoracic needle biopsy includes core needle biopsy besides fine needle aspiration. Any pleural, pulmonary or mediastinal fluid or gas collection is amenable to percutaneous pulmonary catheter drainage. Treatment of haemoptysis of the bronchial artery or pulmonary artery origin, transcatheter embolization of pulmonary arteriovenous malformations and pseudoaneurysms, angioplasty and stenting of the superior vena caval system and percutaneous foreign body retrieval are well established routine procedures, precluding unnecessary surgery. These techniques are safe and effective in experienced hands. Computed tomography is helpful in pre- and postoperative imaging of patients being considered for endobronchial stenting. Many procedures can be performed on an outpatient basis, thus increasing the cost-effectiveness of radiologically guided interventions in the thorax. (+info)
Aberrant branch of the bronchoesophageal artery resembling patent ductus arteriosus in a dog.
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An anomalous shunt between the bronchoesophageal artery and pulmonary artery was diagnosed in a 1-year- old, 3.5 kg female Miniature Dachshund by selective contrast angiography. A cardiac murmur had been observed in the dog during examination at another hospital. The machinery murmur was auscultated at the left side of the base of the heart. Although thoracic radiography revealed mild cardiomegaly, the characteristic findings of patent ductus arteriosus (PDA), including as aortic arch enlargement and pulmonary artery enlargement were not observed. Echocardiography demonstrated shunting of blood flow presumably from the arterial duct at the pulmonary artery carina. Based on the above findings the case was diagnosed as PDA. Angiocardiography was performed to confirm the diagnosis in preparation for surgical treatment, but later we confirmed that the shunt vessel was not PDA, but apparently a branch of the bronchoesophageal artery. The shunt vessel was branching in a complicated manner and shunted to the pulmonary artery. (+info)
Primary racemose hemangioma of the bronchial artery.
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A 44-year-old woman was admitted to our hospital for repeated hemoptysis. Selective angiography of the bilateral bronchial arteries showed them to be enlarged and convoluted, and revealed shunts between the bronchial and pulmonary arteries. The patient was diagnosed as having racemose hemangioma of the bronchial artery. Although embolization of the bronchial artery with gelatin sponges was performed, hemoptysis emerged again about one year later. Finally, segmentectomy of the right lower lung was performed and primary racemose hemangioma of the bronchial artery was histopathologically confirmed. (+info)
The role of the bronchial vasculature in soluble particle clearance.
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Although a role for the airway circulation in the clearance of inhaled particles is generally assumed, there is little information to confirm its importance. We studied the effects of decreased bronchial blood flow on the uptake of the soluble tracer technetium=99m-labeled diethylenetriamine pentaacetic acid (99mTc-DTPA) from subcarinal airways in sheep (n = 7). The bronchial artery was cannulated and perfused with autologous blood at a control flow (0.6 mL/min/kg) or when the perfusion pump was stopped (no flow). (99m)Tc-DTPA (6-10 microL) was delivered by a microspray nozzle inserted through a bronchoscope to a fourth-generation bronchus both during control blood flow conditions and no-flow conditions. Airway retention (by scintigraphy) and blood uptake were monitored for 30 min after the local deposition of (99m(Tc-DTPA. During control flow conditions, 30 min after the delivery of the radiolabel, 21% of the tracer remained at the deposition site. Of the total delivered tracer, maximum blood uptake was 18% (n) = 3). When bronchial perfusion was stopped, airway retention 30 min after deposition increased to 43%, and maximum blood uptake decreased to 7% of the total delivered tracer. Although mucociliary clearance was not directly measured, radiolabel tracer was observed to move progressively from the deposition site up to larger airways and contributed to the overall removal of tracer from the site of deposition during both flow conditions. However, these results demonstrate that decreased bronchial perfusion increases airway retention by limiting vascular uptake of the soluble tracer. These results emphasize the importance of normal perfusion of the airway vasculature for uptake of therapeutic agents delivered specifically to the conducting airways. (+info)
Bronchopulmonary arterial shunting without anatomic anastomosis in the dog.
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The effects of bronchial arterial administration of vasoactive substances on the pulmonary circulation were studied by a new technique for selective catheterization of a bronchial artery in intact dogs. In most experiments, this technique permitted pressor agents to be distributed mainly to one lung with smaller amounts to the other lung. The intercostal arteries were avoided, and in all but 2 of 23 experiments only microscopic quantities of injected India ink could be identified in the distribution of the esophageal and mediastinal branches. These studies indicate that serotonin, angiotensin, histamine, and norepinephrine injected selectively into a bronchial artery increase lobar arterial pressure. Since blood flow was constant and left atrial pressure did not change, the increase in pressure suggests active pulmonary vasoconstriction. Additionally, the responses to bronchial and lobar arterial injections of pressor agents were similar. The contribution of bronchopulmonary shunt flow to pulmonary flow was small, since, under conditions of controlled lobar blood flow, changes in bronchial flow elicited by 65-75-mm Hg changes in bronchial arterial pressure produced little if any change in pressure in the perfused lobar artery or small vein. Bronchoconstriction contributed little to the response to bronchial administration of pressor agents, since responses were similar in the ventilated and the collapsed lobe. Injection of vasoflavine dyes into the bronchial artery showed the close proximity of bronchial and pulmonary arteries and confirmed the bronchial arterial origin of the vasa vasorum of pulmonary arteries. No vasa venorum were identified. Although no direct anatomic bronchial artery-pulmonary artery shunt was identified, ascorbic acid and 5-hydroxydopamine diffused rapidly into intrapulmonary arteries from the bronchial artery. These data suggest that the pulmonary pressor response results from passage of the vasoactive agents from the bronchial artery to the lobar artery through the vasa vasorum and by diffusion. Since no vasa venorum were found, pulmonary venoconstriction probably resulted from pressor agents reaching the veins by way of bronchopulmonary shunt flow. These results suggest a mechanism by which pressor substances present or liberated in the bronchial vascular bed can affect tone in the pulmonary vascular bed. (+info)
Pulmonary and bronchial circulations: contributions to heat and water exchange in isolated lungs.
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The relative contribution of the pulmonary and bronchial circulatory systems to heat and water exchange in normal lungs was evaluated in 20 isolated, in situ perfused dog lungs and in four patients undergoing elective cardiopulmonary bypass. In isolated dog lungs, if the pulmonary artery was perfused at a nominal flow rate (0.5 l/min), bronchial artery perfusion (up to 70 ml/min) did not significantly affect the expired gas temperature. When the lungs were not perfused through either system, 8 min of ventilation with cool, dry gas decreased the temperature of the expired gas by 6.2 +/- 1.4 degrees C. Selective perfusion of bronchial arteries at 68 +/- 10 mmHg resulted in a mean flow rate of 28 +/- 16 ml/min and increased the average temperature of the expired gas by 0.6 degrees C. An increase in the rate of bronchial arterial perfusion to 55 +/- 14 ml/min increased the average temperature of the expired gas by 1.3 degrees C. The time constant for equilibration of tritiated water between the perfusate and the lung parenchyma was 130 +/- 33 min for pulmonary arterial perfusion and 35 +/- 13 min for combined bronchial and pulmonary perfusion, which indicated that filtration of water from high-pressure bronchial vessels facilitated water exchange in the lung interstitium. The rate of tracer equilibration was similar between the perfusate and gas in both variants of perfusion, but the ratios of tracer gas to perfusate were different (0.42 +/- 0.06 for pulmonary, 0.98 +/- 0.07 for combined), which indicates that bronchial vessels contribute mainly to the hydration of the bronchial mucosa. In humans, the bronchial blood flow was capable of maintaining heat supply after the initiation of cardiopulmonary bypass. Before bypass, when both pulmonary and bronchial blood flow were present, the mean time constant of the temperature decay after a switch to ventilation with cool, dry gas was 35 +/- 12 s. The average temperature difference between the blood and expired gas was 2.4 +/- 0.50 degrees C. After 5 min of dry gas ventilation, the temperature difference between the expired gas and initial blood temperature decreased an average of 3.8 +/- 0.06 degrees C (P < 0.05). The time constant of temperature decay increased to 56 +/- 14 s (P < 0.05). We conclude that bronchial perfusion has a less important role in the temperature balance of the respiratory tract compared with pulmonary arterial perfusion because heat flux is "flow limited" but is important in providing water for hydration of the mucosal surface and interstitial compartments of peribronchial tissues. (+info)
Management of life-threatening haemoptysis.
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Massive haemoptysis represents a major medical emergency that is associated with a high mortality. Here we present two cases of life-threatening haemoptysis, the first caused by rupture of an aortic aneurysm into the lung in a 37-yr-old woman with polyarteritis nodosa and the second caused by massive bleeding from an angiectatic vascular malformation in the right main bronchus in a 21-yr-old woman. Fibreoptic bronchoscopy played an essential role in the diagnostic process and management of the respiratory tract. Diagnosis in the first case was obtained by CT scan and the aneurysm was treated surgically. In the second case, bronchial arteriography contributed to both definitive diagnosis and treatment. Initial cardiorespiratory management, diagnostic procedures and definitive therapy are described and reviewed. Adequate early management of the cardiorespiratory system is essential to the outcome. Aggressive measures to elucidate the cause of haemoptysis and prompt therapy are warranted because of the high risk of recurrence. (+info)
Blood flow distribution within the airway wall.
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Altered perfusion of the bronchial mucosal plexus relative to the adventitial plexus may contribute to geometric changes in the airway wall and lumen. We studied bronchial perfusion distribution in sheep by using fluorescent microspheres at baseline and during intrabronchial artery challenge with methacholine chloride (MCh; n = 7). Additionally, we measured airway resistance (Raw) during MCh with control or increased perfusion (n = 9). Raw with MCh was significantly greater for high than control flow. Microspheres in histological sections lodged predominantly in the mucosa (60%), and this was not altered by MCh. However, more microspheres lodged in airways >1-mm in diameter during MCh and increased perfusion than MCh and control flow. In airways < or =1 mm in diameter, fewer microspheres lodged during control than increased flow. If the number of microspheres represents regional agonist access to airway smooth muscle, then the differences observed in Raw can be explained by the distribution of agonist. During challenge, there was greater MCh delivery to larger airways during increased flow and less delivery to smaller airways during control flow. The results demonstrate the effects of axial perfusion distribution on Raw. (+info)