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Fig. 3.71 Internal view of the right ventricle.Arch of aortaSuperior vena cavaTricuspidvalveRight auricleRight atriumAnterior cuspSeptal cuspPosterior cuspPosterior papillary muscleTrabeculae carneaeAnterior papillary muscleChordae tendineaePulmonary trunkPulmonaryvalveLeft auricleSeptal papillary muscleSeptomarginal trabeculaAnterior semilunar cuspRight semilunar cuspLeft semilunar cuspConus arteriosus |
Fig. 3.72 Posterior view of the pulmonary valve.Fig. 3.73 Left atrium. A. Internal view. B. Axial computed tomography image showing the pulmonary veins entering the left atrium. |
Arch of aortaMitral valveLeft auricleABPulmonary arteriesPulmonary veinsValve of foramen ovaleLeft ventricleLeft atriumAscending aortaRight ventricleRight pulmonary veinLeft atriumEsophagusThoracic aortaLeft pulmonary vein |
Fig. 3.74 Internal view of the left ventricle.Arch of aortaCoronary sinusMitral valve posterior cuspPulmonary arteriesPulmonary veinsAnterior papillarymuscleMitral valve anterior cuspPosterior papillarymuscleChordae tendineaeTrabeculae carneaeLeft atrium |
Fig. 3.75 Anterior view of the aortic valve.Fig. 3.76 Cardiac skeleton (atria removed).Right fibrous trigoneLeft fibrous trigoneLeft atrioventricular ringFibrous ring of pulmonary valveAtrioventricular bundleRight atrioventricular ringFibrous ring of aortic valveAntAntAntRtRtPostPostPostPosteriorAnteriorLeftRightSeptalLtLt |
Fig. 3.77 Cardiac vasculature. A. Anterior view. B. Superior view (atria removed). |
Fig. 3.78 A. Anterior view of coronary arterial system. Right dominant coronary artery. B. Left anterior oblique view of right coronary artery. |
C. Right anterior oblique view of left coronary artery.Right marginal branch Posterior interventricular branchRight coronary artery Left marginal branch Circumflex branchAnterior interventricular branchRight marginal branchof right coronary artery Right coronary arteryRight atriumRight ventricleSinu-atrial nodal branchof right coronary arteryABCPosterior interventricularbranch of right coronary artery Anterior interventricularbranch of leftcoronary artery Left coronary arteryCircumflex branchof left coronary arteryLeft marginal branchof circumflex branchDiagonal branch ofanterior interventricular branchLeft auricleLeft ventricle |
Fig. 3.79 Left dominant coronary artery.Right marginal branchof right coronary arteryRight coronary arteryPosterior interventricular branch ofcircumflex branch of left coronary arterySinu-atrial nodal branchof left coronary arteryAnterior interventricularbranch of left coronary artery Left coronary arteryCircumflex branchof left coronary arteryLeft marginal branchof circumflex branchDiagonal branch ofanterior interventricular branch |
Fig. 3.80 A and B. Axial maximum intensity projection (MIP) CT image through the heart. A. Normal anterior interventricular (left anterior descending) artery. B. Stenotic (calcified) anterior interventricular (left anterior descending) artery. C and D. Vertical long axis multiplanar reformation (MRP) CT image through the heart. C. Normal anterior interventricular (left anterior descending) artery. D. Stenotic (calcified) anterior interventricular (left anterior descending) artery. |
Fig. 3.81 Heart sounds and how they relate to valve closure, the electrocardiogram (ECG), and ventricular pressure. |
RPQST1st2nd1stSYSTOLESYSTOLEDIASTOLEVentricularpressureECGHeartsoundsAtrial contractionClosure of mitraland tricuspid valvesClosure of aortic andpulmonary valves"lub""lub""dub" |
Fig. 3.82 Major cardiac veins. A. Anterior view of major cardiac veins. B. Posteroinferior view of major cardiac veins. |
Fig. 3.83 Conduction system of the heart. A. Right chambers. B. Left chambers. |
Fig. 3.84 Cardiac plexus. A. Superficial. B. Deep.Left vagus nerveRight vagus nerveVagal cardiac branchesVagal cardiac branchesCardiac nerves fromsympathetic trunkSuperior vena cavaArch of aortaSuperficial cardiac plexusPulmonary trunkLeft recurrent laryngeal nerveRight recurrent laryngeal nerveLeft vagus nerveRight vagus nerveCardiac nerves from sympathetic trunkDeep cardiac plexusVagal cardiac branchesVagal cardiac branchesAB |
Fig. 3.85 Major vessels within the middle mediastinum. A. Anterior view. B. Posterior view. |
Ascending aortaPulmonary trunkSuperiorvena cavaSuperior vena cavaInferior vena cavaOblique pericardial sinusRight pulmonaryarteryRight pulmonaryveinsRight atriumLeft pulmonaryveinsLeft pulmonaryarteryArch of aortaAB |
Fig. 3.86 Structures in the superior mediastinum.Right internal jugular veinRight common carotid arteryLeft common carotid arteryLeft subclavian arteryRight subclavian arteryRight pulmonary arteryLeft pulmonary arteryPulmonary trunkLeft subclavian veinLeft brachiocephalic veinRight brachiocephalic veinRight subclavian veinLeft internal jugular veinTracheaEsophagusEsophagusArch of aortaAscending aortaThoracic aortaLeft main bronchusRight main bronchusSuperior vena cava |
Fig. 3.87 Cross section through the superior mediastinum at the level of vertebra TIII. A. Diagram. B. Axial computed tomography image. |
ThymusManubrium of sternumLeft brachiocephalic veinRight brachiocephalic veinBrachiocephalic trunkLeft phrenic nerveRight phrenic nerveLeft vagus nerveLeft recurrent laryngeal nerveRight vagus nerveLeft common carotid arteryLeft subclavian arteryThoracic ductEsophagusTIIITracheaABLeft common carotid arteryEsophagusLeft subclavian arteryTracheaLeft brachiocephalic veinBrachiocephalic trunkRight brachiocephalic vein |
Fig. 3.88 Superior mediastinum with thymus removed.Fig. 3.89 Left superior intercostal vein.Fig. 3.90 Superior mediastinum with thymus and venous channels removed. |
Fig. 3.91 Axial CT showing aortic dissection.Fig. 3.92 Cross section through the superior mediastinum at the level of vertebra TIV. A. Diagram. B. Axial computed tomography image. |
Manubrium of sternumThymusLeft phrenic nerveRight phrenicnerveArch of aortaLeft vagus nerveRight vagusnerveLeft recurrent laryngeal nerveThoracic ductTIVSuperior vena cavaTracheaArch ofazygos veinArch ofazygos veinEsophagusBAEsophagusTracheaArch of aortaSuperior vena cava |
Fig. 3.93 Trachea in the superior mediastinum.TracheaLeft brachiocephalicveinBrachiocephalictrunkLeft mainbronchusRight main bronchusPulmonary trunkSuperior venacavaArch of aortaTIV/V vertebrallevel |
Fig. 3.94 Right vagus nerve passing through the superior mediastinum. |
Fig. 3.95 Left vagus nerve passing through the superior mediastinum. |
Fig. 3.96 Left recurrent laryngeal nerve passing through the superior mediastinum. |
Left recurrent laryngeal nerveLeft vagus nerveRight mainbronchusTIV/VvertebrallevelLeft main bronchusLigamentum arteriosumLeft pulmonary arteryLeft subclavian arteryPulmonary trunkEsophagusEsophagusTracheaThoracic aortaArch of aorta |
Fig. 3.97 Esophagus.Right main bronchusLeft main bronchusLeft subclavian arteryLeft common carotid arteryEsophagusEsophagusTracheaThoracic aortaArch of aortaBrachiocephalic trunkDiaphragm |
Fig. 3.98 Sites of normal esophageal constrictions.EsophagusTracheaPharynxDiaphragmJunction of esophagus with pharynxWhere esophagus iscrossed by arch ofaortaWhere esophagus is compressed by left main bronchusAt the esophageal hiatusPosition ofesophagusposterior toleft atrium |
Fig. 3.99 Esophageal plexus.Fig. 3.100 Axial CT showing esophageal cancer.Fig. 3.101 Thoracic aorta and branches.Left subclavian arterySupremeintercostal arterySuperior leftbronchialarteryRightbronchialarteryEsophagusEsophagusTracheaArch of aortaPosteriorintercostalarteriesMediastinalbranchesEsophageal branchesFig. 3.102 Azygos system of veins.Left superior intercostal veinRight superior intercostal veinAccessory hemiazygos veinHemiazygos veinAzygos veinOpening of azygos veininto superior vena cavaPosterior intercostal veinRight subcostal veinAscending lumbar veinRight ascending lumbar veinInferior vena cava |
Fig. 3.103 Thoracic duct.Fig. 3.104 Thoracic portion of sympathetic trunks.Fig. 3.105 Anterior view of chest wall with the locations of skeletal structures shown. A. In women. The location of the nipple relative to a specific intercostal space varies depending on the size of the breasts, which may not be symmetrical. B. In men. Note the location of the nipple in the fourth intercostal space. |
ClavicleCostal cartilageCoracoid processCostal marginJugular notchSternoclavicular jointManubrium of sternumRib IRib XXiphoid processASternal angleIIIIIIVVVIVIIVIIIIXBody of sternum |
ClavicleCostal cartilageCoracoid processSternal angleCostal marginJugular notchSternoclavicular jointManubrium of sternumRib IRib XBody of sternumXiphoid processBIIIIIIVVVIVIIVIIIIX |
Fig. 3.106 A. Close-up view of nipple and surrounding areola of the breast. B. Lateral view of the chest wall of a woman showing the axillary process of the breast. |
Fig. 3.107 Anterior view of the chest wall of a man showing the locations of various structures related to the TIV/V level. |
Fig. 3.108 Anterior view of the chest wall of a man showing the locations of different structures in the superior mediastinum as they relate to the skeleton. |
Right internal jugular veinRight common carotid arteryLeft common carotid arteryLeft subclavian arteryRight subclavian arteryRight pulmonaryarteryLeft pulmonaryarteryPulmonary trunkLeft subclavian veinLeft brachiocephalicveinRight brachiocephalic veinRight subclavian veinLeft internal jugular veinTracheaEsophagusEsophagusArch of aortaAscending aortaThoracic aortaLeft main bronchusRight mainbronchusSuperiorvena cava |
Fig. 3.109 Anterior view of the chest wall of a man showing skeletal structures and the surface projection of the heart. |
Fig. 3.110 Anterior view of the chest wall of a man showing skeletal structures, heart, location of the heart valves, and auscultation points. |
Fig. 3.111 Views of the chest wall showing the surface projections of the lobes and the fissures of the lungs. A. Anterior view in a woman. On the right side, the superior, middle, and inferior lobes are illustrated. On the left side, the superior and inferior lobes are illustrated. |
B. Posterior view in a woman. On both sides, the superior and inferior lobes are illustrated. The middle lobe on the right side is not visible in this view. |
Fig. 3.112 Views of the chest wall. A. Posterior view in a woman with arms abducted and hands positioned behind her head. On both sides, the superior and inferior lobes of the lungs are illustrated. When the scapula is rotated into this position, the medial border of the scapula parallels the position of the oblique fissure and can be used as a guide for determining the surface projection of the superior and inferior lobes of the lungs. B. Lateral view in a man with his right arm abducted. The superior, middle, and inferior lobes of the right lung are illustrated. The oblique fissure begins posteriorly at the level of the spine of vertebra TIV, passes inferiorly crossing rib IV, the fourth intercostal space, and rib V. It crosses the fifth intercostal space at the midaxillary line and continues anteriorly along the contour of rib VI. The horizontal fissure crosses rib V in the midaxillary space and continues anteriorly, crossing the fourth intercostal space and following the contour of rib IV and its costal cartilage to the sternum. |
Fig. 3.113 Views of the chest wall of a man with stethoscope placements for listening to the lobes of the lungs. A. Anterior views. |
B. Posterior views.Apex of right lungApex of left lungSuperior lobe of right lungSuperior lobe of left lungMiddle lobe of right lungInferior lobe of right lungInferior lobe of left lungABIIIIIIIVVVIVIIVIIIIXXXIXIIIIIIIIIVVVIVIIVIIIIXX |
Fig. 3.114 A. Normal left coronary artery angiogram. B. Left coronary artery angiogram showing decreased flow due to blockages. |
C. Mechanism for perceiving heart pain in T1–4 dermatomes.Fig. 3.115 Axial maximum intensity projection (MIP) CT image through the heart. A. Normal anterior interventricular (left anterior descending) artery. B. Stenotic (calcified) anterior interventricular (left anterior descending) artery. |
eFig. 3.116 Cervical ribs. A. Neck radiograph demonstrating bilateral cervical ribs. B. Coronal computed tomography image showing cervical ribs. |
eFig. 3.117 Chest radiograph demonstrating an air/fluid level in the pleural cavity. |
eFig. 3.118 Chest radiograph of an individual with a pacemaker. The pacemaker wires (2) can be seen traveling through the venous system to the heart where one ends in the right atrium and the other ends in the right ventricle. |
eFig. 3.119 Chest radiograph demonstrating translucent notches along the inferior border of ribs III to VI. |
eFig. 3.120 A. CT image of aortic dissection. B. Normal aorta (left) and an aortic dissection (right). The line in the right figure indicates the plane of the CT scan shown in A. |
The true lumen surroundedby the collapsed intima and mediaCollapsed intima and mediaABThe false lumenThe false lumenAscendingaortaThoracic aortaThe true lumenEntrypointReturnpoint eFig. 3.121 Chest radiograph showing left upper lobe infection. |
Table 3.1 Muscles of the pectoral regionTable 3.2 Muscles of the thoracic wallTable 3.3 Branches of the thoracic aortaIn the clinicAxillary tail of breastIt is important for clinicians to remember when evaluating the breast for pathology that the upper lateral region of the breast can project around the lateral margin of the pectoralis major muscle and into the axilla. This axillary process (axillary tail) may perforate deep fascia and extend as far superiorly as the apex of the axilla. |
In the clinicBreast cancer is one of the most common malignancies in women. It develops in the cells of the acini, lactiferous ducts, and lobules of the breast. Tumor growth and spread depends on the exact cellular site of origin of the cancer. These factors affect the response to surgery, chemotherapy, and radiotherapy. Breast tumors spread via the lymphatics and veins, or by direct invasion. |
When a patient has a lump in the breast, a diagnosis of breast cancer is confirmed by a biopsy and histological evaluation. Once confirmed, the clinician must attempt to stage the tumor. |
Staging the tumor means defining the: size of the primary tumor, exact site of the primary tumor, number and sites of lymph node spread, and organs to which the tumor may have spread. |
Computed tomography (CT) scanning of the body may be carried out to look for any spread to the lungs (pulmonary metastases), liver (hepatic metastases), or bone (bony metastases). |
Further imaging may include bone scanning using radioactive isotopes, which are avidly taken up by the tumor metastases in bone, and PET-CT, which can visualize active foci of the metastatic disease in the body. |
Lymph drainage of the breast is complex. Lymph vessels pass to axillary, supraclavicular, and parasternal nodes and may even pass to abdominal lymph nodes, as well as to the opposite breast. Containment of nodal metastatic breast cancer is therefore potentially difficult because it can spread through many lymph node groups. |
Subcutaneous lymphatic obstruction and tumor growth pull on connective tissue ligaments in the breast, resulting in the appearance of an orange peel texture (peau d’orange) on the surface of the breast. Further subcutaneous spread can induce a rare manifestation of breast cancer that produces a hard, woody texture to the skin (cancer en cuirasse). |
A mastectomy (surgical removal of the breast) involves excision of breast tissue. Within the axilla the breast tissue must be removed from the medial axillary wall. Closely applied to the medial axillary wall is the long thoracic nerve. Damage to this nerve can result in paralysis of the serratus anterior muscle, producing a characteristic “winged” scapula. It is also possible to damage the nerve to the latissimus dorsi muscle, and this may affect extension, medial rotation, and adduction of the humerus. |
In the clinicCervical ribs are present in approximately 1% of the population. |
A cervical rib is an accessory rib articulating with vertebra CVII; the anterior end attaches to the superior border of the anterior aspect of rib I. |
Plain radiographs may demonstrate cervical ribs as small horn-like structures (see Fig. 3.106). |
It is often not appreciated by clinicians that a fibrous band commonly extends from the anterior tip of the small cervical ribs to rib I, producing a “cervical band” that is not visualized on radiography. In patients with cervical ribs and cervical bands, structures that normally pass over rib I (see Fig. 3.7) are elevated by, and pass over, the cervical rib and band. |
Clinically, “thoracic outlet syndrome” is used to describe symptoms resulting from abnormal compression of the brachial plexus of nerves as it passes over the first rib and through the axillary inlet into the upper limb. The anterior ramus of T1 passes superiorly out of the superior thoracic aperture to join and become part of the brachial plexus. The cervical band from a cervical rib is one cause of thoracic outlet syndrome by putting upward stresses on the lower parts of the brachial plexus as they pass over the cervical band and related cervical rib. |
In the clinicCollection of sternal bone marrowThe subcutaneous position of the sternum makes it possible to place a needle through the hard outer cortex into the internal (or medullary) cavity containing bone marrow. Once the needle is in this position, bone marrow can be aspirated. Evaluation of this material under the microscope helps clinicians diagnose certain blood diseases such as leukemia. |
In the clinicSingle rib fractures are of little consequence, though extremely painful. |
After severe trauma, ribs may be broken in two or more places. If enough ribs are broken, a loose segment of chest wall, a flail segment (flail chest), is produced. When the patient takes a deep inspiration, the flail segment moves in the opposite direction to the chest wall, preventing full lung expansion and creating a paradoxically moving segment. If a large enough segment of chest wall is affected, ventilation may be impaired and assisted ventilation may be required until the ribs have healed. |
In the clinicSurgical access to the chestA surgical access is potentially more challenging in the chest given the rigid nature of the thoracic cage. Moreover, access is also dependent upon the organ that is operated upon and its relationships to subdiaphragmatic structures and structures in the neck. |
The most common approaches are a median sternotomy and a lateral thoracotomy. |
A median sternotomy involves making a vertical incision in the sternum from just below the sternal notch to the distal end of the xiphoid process. Care must be taken not to cause injury to the vessels, in particular to the brachiocephalic veins. Bleeding from the branches of the internal thoracic artery can occur and needs to be controlled. Opening the sternum causes traction on the upper ribs and may lead to rib fractures. Sometimes partial sternotomy is performed with the incision involving only the upper part of the sternum and ending at the level of manubriosternal junction or just below. A median sternotomy allows access to the heart, including coronary arteries and valves, pericardium, great vessels, anterior mediastinum, and thymus, as well as to the lower trachea. It can also be used for removal of retrosternal goiter or during esophagectomy. The incision can be extended laterally into the supraclavicular region, giving access to the subclavian and carotid arteries. |
A lateral thoracotomy gives access to the ipsilateral hemithorax and its contents including the lung, mediastinum, esophagus, and heart (left lateral thoracotomy) (Fig. 3.33). |
However, it involves division of muscles of the thoracic wall which leads to significant postoperative pain that needs to be well controlled to avoid restricted lung function. The incision starts at the anterior axillary line and then passes below the tip of the scapula and is extended superiorly between the posterior midline and medial border of the scapula. The pleural cavity is entered through an intercostal space. In older patients and those with osteoporosis, a short segment of rib is often resected to minimize the risk of a rib fracture. |
Minimally invasive thoracic surgery (video-assisted thoracic surgery [VATS]) involves making small (1-cm) incisions in the intercostal spaces, placing a small camera on a telescope, and manipulating other instruments through additional small incisions. A number of procedures can be performed in this manner, including lobectomy, lung biopsy, and esophagectomy. |
In the clinicInsertion of a chest tube is a commonly performed procedure and is indicated to relieve air or fluid trapped in the thorax between the lung and the chest wall (pleural cavity). This procedure is done for pneumothorax, hemothorax, hemopneumothorax, malignant pleural effusion empyema, hydrothorax, and chylothorax, and also after thoracic surgery. |
The position of the thoracostomy tube is usually between the anterior axillary and midaxillary anatomical lines from anterior to posterior and in either the fourth or fifth intercostal space. The position of the ribs in this region should be clearly marked. Anesthetic should be applied to the superior border of the rib and the inferior aspect of the intercostal space, including one rib and space above and one rib and space below. The neurovascular bundle runs in the neurovascular plane, which lies in the superior aspect of the intercostal space (just below the rib); hence, the reason for positioning the tube on the superior border of a rib (i.e., at the lowest position in the intercostal space). |
Chest tube insertion is now commonly done with direct ultrasound guidance. This approach allows the physician both to assess whether the pleural effusion is simple or complex and loculated, and to select the safest site for entering the pleural space. In some cases of pneumothorax, a chest drain can be inserted under computed tomography-guidance, especially in patients with underlying lung disease where it is difficult to differentiate a large bulla from free air in the pleural space. |
In the clinicLocal anesthesia of intercostal nerves produces excellent analgesia in patients with chest trauma and in those patients requiring anesthesia for a thoracotomy, mastectomy, or upper abdominal surgical procedures. |
The intercostal nerves are situated inferior to the rib borders in the neurovascular bundle. Each neurovascular bundle is situated deep to the external and internal intercostal muscle groups. |
The nerve block may be undertaken using a “blind” technique or under direct imaging guidance. |
The patient is placed in the appropriate position to access the rib. Typically, under ultrasound guidance, a needle may be advanced into the region of the subcostal groove, followed by an injection with a local anesthetic. Depending on the type of anesthetic used, analgesia may be shortor long-acting. |
Given the position of the neurovascular bundle and the subcostal groove, complications may include puncture of the parietal pleura and an ensuing pneumothorax. Bleeding may also occur if the artery or vein is damaged during the procedure. |
In the clinicIn cases of phrenic nerve palsy, diaphragmatic paralysis ensues, which is manifested by the elevation of the diaphragm muscle on the affected side (Fig. 3.36). The most important cause of the phrenic nerve palsy that should never be overlooked is malignant infiltration of the nerve by lung cancer. Other causes include postviral neuropathy (in particular, related to varicella zoster virus), trauma, iatrogenic injury during thoracic surgery, and degenerative changes in the cervical spine with compression of the C3–C5 nerve roots. |
Most patients with unilateral diaphragmatic paralysis are asymptomatic and require no treatment. Some may report shortness of breath, particularly on exertion. Bilateral paralysis of the diaphragm is rare but can cause significant respiratory distress. |
Surgical plication of the diaphragm can be performed in cases with respiratory compromise and is often done laparoscopically. The surgeon creates folds in the paralyzed diaphragm and sutures them in place, reducing the mobility of the diaphragmatic muscle. There is usually good improvement in lung function, exercise tolerance, and shortness of breath after the procedure. |
In the clinicA pleural effusion occurs when excess fluid accumulates within the pleural space. As the fluid accumulates within the pleural space the underlying lung is compromised and may collapse as the volume of fluid increases. Once a pleural effusion has been diagnosed, fluid often will be aspirated to determine the cause, which can include infection, malignancy, cardiac failure, hepatic disease, and pulmonary embolism. A large pleural effusion needs to be drained to allow the collapsed part of the lung to reexpand and improve breathing (Fig. 3.41). |
In the clinicA pneumothorax is a collection of gas or air within the pleural cavity (Fig. 3.42). When air enters the pleural cavity the tissue elasticity of the parenchyma causes the lung to collapse within the chest, impairing the lung function. Occasionally, the gas within the pleural cavity may accumulate to such an extent that the mediastinum is “pushed” to the opposite side, compromising the other lung. This is termed a tension pneumothorax and requires urgent treatment. |
Most pneumothoraces are spontaneous (i.e., they occur in the absence of no known pathology and no known lung disease). In addition, pneumothoraces may occur as a result of trauma, inflammation, smoking, and other underlying pulmonary diseases. Certain pulmonary metastases, such as in patients with osteosarcoma, may cause spontaneous pneumothorax especially after chemotherapy. The occurrence of pneumothorax interferes with cancer treatment and increases mortality. |
The symptoms of pneumothorax are often determined by the degree of air leak and the rate at which the accumulation of gas occurs and the ensuing lung collapses. They include pain, shortness of breath, and cardiorespiratory collapse, if severe. |
In the clinicImaging the lungsMedical imaging of the lungs is important because they are one of the commonest sites for disease in the body. While the body is at rest, the lungs exchange up to 5 L of air per minute, and this may contain pathogens and other potentially harmful elements (e.g., allergens). Techniques to visualize the lung range from plain chest radiographs to high-resolution computed tomography (CT), which enables precise localization of a lesion within the lung. |
In the clinicHigh-resolution computed tomography (HRCT) is a diagnostic method for assessing the lungs but more specifically the interstitium of the lungs. The technique involves obtaining narrow cross-sectional slices of 1 to 2 mm. These scans enable the physician and radiologist to view the patterns of disease and their distribution. Diseases that may be easily demonstrated using this procedure include emphysema (Fig. 3.52), pneumoconiosis (coal worker’s pneumoconiosis), and asbestosis. HRCT is also useful in regular follow-ups of patients with interstitial disease to monitor disease progression. |
In the clinicPatients who have an endobronchial lesion (i.e., a lesion within a bronchus) may undergo bronchoscopic evaluation of the trachea and its main branches (Fig. 3.53). The bronchoscope is passed through the nose into the oropharynx and is then directed by a control system past the vocal cords into the trachea. The bronchi are inspected and, if necessary, small biopsies are obtained. Bronchoscopy can also be used in combination with ultrasound (a technique known as EBUS, endobronchial ultrasound). An ultrasound probe is inserted through a working channel of the bronchoscope to visualize the airway walls and adjacent structures. EBUS allows an accurate localization of the lesion and therefore provides a higher diagnostic yield. It can be used for sampling of mediastinal and hilar lymph nodes or to assist in transbronchial biopsy of pulmonary nodules. |
In the clinicIt is important to stage lung cancer because the treatment depends on its stage. |
If a small malignant nodule is found within the lung, it can sometimes be excised and the prognosis is excellent. Unfortunately, many patients present with a tumor mass that has invaded structures in the mediastinum or the pleurae or has metastasized. The tumor may then be inoperable and is treated with radiotherapy and chemotherapy. |
Spread of the tumor is by lymphatics to lymph nodes within the hila, mediastinum, and root of the neck. |
A key factor affecting the prognosis and ability to cure the disease is the distant spread of metastases. Imaging methods to assess spread include plain radiography (Fig. 3.54A), computed tomography (CT; Fig. 3.54B,C), and magnetic resonance imaging (MRI). Increasingly, radionuclide studies using fluorodeoxyglucose positron emission tomography (FDG PET; Fig. 3.54D) are being used. |
In FDG PET a gamma radiation emitter is attached to a glucose molecule. In areas of high metabolic activity (i.e., the tumor), excessive uptake occurs and is recorded by a gamma camera. |
In the clinicPericarditis is an inflammatory condition of the pericardium. Common causes are viral and bacterial infections, systemic illnesses (e.g., chronic renal failure), and after myocardial infarction. |