Ebook Chest radiology: Part 2

(BQ) Part 2 book Chest radiology has contents: Miscellaneous cluster, positron e mission tomography computed tomography, diverse conditions, pediatric chest, esophagus, mediastinum, heart,.... and other contents.

Pericardial Effusion

Pericardial sac normally contains 15 to 50 ml of pericardial fluid

Pericardial effusion is an abnormal accumulation of fluid in the

pericardial cavity Excessive fluid accumulation leads to increased

intrapericardial pressure and when this is enough pressure to

adversely affect heart function, it is called cardiac tamponade

Pericardial effusion usually results from a disturbed equilibrium

between the production and re-absorption of pericardial fluid,

or from a structural abnormality that allows fluid to enter the

pericardial cavity

Types of pericardial effusion are:

a Transudative (congestive heart failure, myxoedema, neph rotic

syndrome)

b Exudative (tuberculosis, spread from empyema)

c Hemorrhagic (trauma, rupture of aneurysms, malignant

effusion)

d Malignant (due to fluid accumulation caused by metastasis)

Causes of pericardial effusion are:

a Idiopathic

b Inflammatory

i Postmyocardial infarction (Dressler’s syndrome)

ii Connective tissue disorders

Fig 8.1 Heart appears as a ular enlargement giving a water bottle configuration

glob-estimated USG can be used as a therapeutic moda lity to aspirate

the pericardial fluid CT chest is also diagnostic (Fig 8.2)

Tuberculous Effusions

Diseases of the pericardium are clearly visualized on CT It

detects thickening of the pericardium and calcification with a high

degree of sensitivity and specificity and is an accurate method

Fig 8.2 CT chest shows pericardial effusion

calcification CT also demonstrates the presence of additional pleural effusions or ascites (Figs 8.3A and B).

Constrictive Pericarditis

Constrictive pericarditis (CP) is stiffening or reduction in the elasticity of the pericardium, resulting in impaired filling of the heart The symptoms of CP include exercise intolerance, dyspnea, hepatic and renal failure, it appears insidiously Imaging findings

of calcifications and thickening of the pericardium, may be present (Fig 8.4), but the reliable and important findings are related to the filling pattern of the heart Patients respond dramatically to a complete surgical pericardiectomy when it is performed early in the disease process; therefore, it is important to consider CP when making the diagnosis

Figs 8.3A and B Pericardial effusion, pleural effusion and ascites in

a 13-year-old female (A) CT chest shows pericardial effusion with few air pockets (postdrainage), the fluid thickness is up to 25 mm, outer layer of pericardium is thickened Bilateral pleural effusion is present (B) Free fluid is present in the perihepatic and paracolic gutters and pericholecystic area

Atherosclerosis

Atherosclerosis is hardening of the arteries due to deposition

of cholesterol and other fat substances within the walls of the

arteries within a fibrous coat; these fatty deposits are called

plaques Plaque builds up on the inner wall of the intima with

secondary degeneration and fibrous replacement of media in

the arteries (Figs 8.5A and B) It is a progressive disease more

common in elderly and in males Atherosclerosis is a common

disorder of the arteries and is leading cause of thoracic aortic

aneurysm distal to left subclavian artery The other arteries

frequently affected are the coronary arteries and the cerebral

arteries

Redundant and Tortuous Aorta

Normal configuration of the aorta is maintained due to elasticity

of its wall As age advances there is degenerative change in

the elastic fibers of wall, it loses its elasticity and may become

redundant and tortuous Patients usually remain asymptomatic

border with roughening of cardiac outline as a result of pleuropericardial thick ening

in constrictive peri carditis

On chest X-ray, it may appear as a widening of the mediastinum It may mimic aneurysm However, cross-sectional imaging confirms the nonaneurysmal tortuous configuration and redundancy of the aorta (Figs 8.6A and B).

Thoracic Aortic Aneurysm

A true aneurysm is defined as a localized dilatation of the aorta with

50 percent over the normal diameter and includes all three layers of the vessel, intima, media and adventitia Thoracic aortic aneurysms are less common than aneurysms of the abdominal aorta

There are two major types of aneurysm morphology: fusiform and saccular A pseudoaneurysm or false aneurysm is a collection

of blood and connective tissue outside the aortic wall, usually the result of a rupture

Figs 8.5A and B (A) Plain CT abdomen No clear demarcation is seen between the wall and lumen of aorta (B) Contrast CT abdomen clearly demarcates the aortic wall thickening and patent lumen

The incidence of thoracic aortic aneurysm is estimated to be

around six cases per lac patient years. Thoracic aneurysms occur

most commonly in the sixth and seventh decade of life

The vast majority of thoracic aneurysms are associated with

atherosclerosis Male:female ratio is 3:1 Hypertension is an

important risk factor, being present in 60 percent of patients

Asymptomatic aneurysms are incidentally detected on routine

X-ray chest The aortic aneurysm produces mediastinal widening

or alters contour of the heart or aotic outline (Figs 8.7 and 8.8)

Figs 8.6A and B Scout CT image of chest (A) shows prominent

des-cending aorta raising a suspicion of aneurysm Aortic recon struction

following contrast CT of chest and abdomen (B) shows no aneurysm but

only tortuous and elongated dilatation of thoracic aorta

Figs 8.7A and B X-ray chest on penetrated AP projection (A) shows alt ered contour of distal thoracic aorta and (B) late ral view shows the aneurysmal dilat ation of distal part of thoracic aorta

Figs 8.8A and B (A) X-ray chest PA view of another case shows dilatation

of distal thoracic aorta which is displaced to the left and is returning to its normal position at the level of diaphragm (B) Lateral view of thoracolumbar spine shows scalloping of the anterior margins of bodies of LV1 and LV2

limited availability, increased cost and lower resolution than

traditional contrast angiography

Coarctation of Aorta

Coarctation of aorta is a congenital aortic narrowing in the region

of the isthmus

Figs 8.9A to C Contrast-enhanced CT scan (A), and (B) axial sections,

and (C) coronal reformatted image shows a large descending thoracic

aorta aneurysm with a large com ponent of intramural thrombus

(arrows) which shows no contrast uptake Calcification is present in the

wall abutting the thrombus (arrow) in (A)

A

There is a characteristic shelf-like narrowing of the aorta which usually occurs just beyond the origin of the left subclavian artery (Figs 8.11A to D) The severity of coarctation or narrowing can vary considerably and it is this severity which determines the age of presentation (Figs 8.11E to G) It is more common in males (M:F = 4:1) and is rare in blacks.

The collateral circulation distal to the coarctation is through the subclavian arteries and its branches like internal mammary artery to intercostals, scapular artery to anterior spinal artery, transverse cervical artery to lateral thoracic artery

Fig 8.10 Thoracoabdominal aortic angiogram shows a fusiform aneurysm proximal to the origin of renal arteries and extends to just above the abdomen The dilatation of distal thoracic aorta seen on X-ray film is actually the redundant aorta

Figs 8.11A to D CT aortic angiography in a case of postductal

coarctation of aorta (A) Aortic arch shows reduction in diameter of

descending aorta as compared to ascending (B and C) The diameter of

ascending aorta (upright arrow) is maintained but that of descending

aorta (down pointing arrow) has abruptly reduced (D) Return of normal

caliber of descending aorta

Figs 8.11E to G Return of normal caliber of descending aorta

(E and F) Coronal and sagittal reformatted image shows the actual site of coar ctation (G) Color coded CT angiogram shows exact location

of narrowing

Rib notching (Fig 8.12) is seen in coarctation of aorta and

it usually takes several years to develop It is due to pressure erosion by the enlarged tortuous collaterals intercostal arteries It

is typically bilateral and is best seen on the inferior aspect of the posterior thirds of 4th to 9th ribs It may be unilateral Chest X-ray showing notching of posterior ribs bilaterally most prominent along inferior borders is likely a case of aortic coarctation

Tetralogy of Fallot

Tetralogy of Fallot is the most common cyanotic heart disease

Morphologic abnormalities of tetralogy of Fallot are as follows:

i Right ventricular outflow tract obstruction

ii Ventricular septal defect

iii Right ventricular hypertrophy

iv Overriding of aorta

On chest X-ray the right ventricular hypertrophy is seen as

elevated left ventricle Combined with a small or absent main

pulmonary artery segment, the heart shows the classic

boot-shaped appearance (Fig 8.13) Vascularity of the pulmonary artery

is reduced A right-sided arch is present in 25 percent of cases

Echocardiography is the primary imaging method in

sus-pected cases Echocardiography should be used to confirm

Fig 8.12 X-ray chest shows rib notching on the inferior aspect of the posterior 4th to 7th ribs

radiographic findings that are suggestive of tetralogy of Fallot Intracardiac anomalies, including pulmonary infundibular and valvular stenosis and the position of the aortic root overriding and the ventricular septal defect are identified.

CT is useful for the evaluation of surgical complications such

as infection or pseudoaneurysm formation Also to identify airway compression that is caused by a large ascending aorta that is associated with tetralogy of Fallot and MRI can be used to identify the morphologic abnormalities

Cardiac catheterization and angiography is often required

in addition to echocardiography because precise assessment of anatomy is essential in surgical planning

Mitral Stenosis

Mitral stenosis (MS) results in the reduction of blood flow across the mitral valve due to fusion of leaflet commissures The most common cause of MS is rheumatic fever Chest radiograph provides

Fig 8.13 X-ray chest of a

one-year-old child shows a boot-shaped heart produced by elevated left ventricle combined with a small or absent main pulmonary artery segment and vascularity of the pulmonary artery is reduced

signs of LA enlargement are upward displacement of left main

bronchus resulting in widening of carinal angle (Figs 8.14A and B)

and deviation of the middle third of descending thoracic aorta to the

left (Bedford sign)

Figs 8.14A and B X-ray chest in mitral stenosis Double density due to

enlarged left atrium (white arrow) is seen and there is increased carinal

angle (black arrow) Normal carinal angle is 40–65° The left heart border

is straightened There is prominence of upper lobe vessels in the lungs

as appreciated by increased density in upper lobes

Hemodynamic changes in the pulmonary circulation are sensitive indicators of the severity of the disease displayed as prominence

of upper lobe vessels, diminution of lower lobe vessels (Figs 8.14A and B), Kerley B lines and pleural effusion suggests pulmonary venous hypertension

Enlargement of the main and branch pulmonary arteries indicate pulmonary arterial hypertension Double right heart border is due to enlargement of left atrium Hemosiderosis and ossific pulmonary nodules are noted in chronic long-standing cases Esophagus is pushed posteriorly and to the right (Figs 8.15A and B) due to enlarged left atrium

Figs 8.15A and B C-shaped extrinsic impression on the esophagus pushing it to the right (A), and (B) posteriorly (arrow) due to enlarged left atrium

heart goes to the right side of the heart This can occur either

through a hole in the ventricular or atrial septum or through a

hole in the walls of the great vessels leaving the heart Hence

L-R shunt occurs when oxygen-rich pulmonary venous blood

entering the left atrium is shunted to the right side of the ventricle

to be ejected into the pulmonary artery Left-to-right shunts

include atrial septal defect (ASD), ventricular septal defect (VSD),

patent ductus arteriosus (PDA), and patent foramen ovale (PFO)

Septal Defect (L to R Shunt)

Atrial Septal Defect

Atrial septal defect (ASD) is the most common congenital heart

disease diagnosed in adults It is classified into four types:

i Ostium secondum ASD: Exaggerated resorptive process of

Hemodynamics changes occur after birth due to increase in

phy siological pressure of left atrium (LA) with flow of blood

atrium (RA) to right ventricle (RV) and is termed as left to right shunt (L-R shunt), volume overload is well-tolerated during child -hood Later right ventricle dilates leading to right heart failure.

Chest X-ray is usually normal if the shunt is small In cases

of large shunt cardiomegaly and increased pulmonary vas cularity

is seen Aorta appears small with normal aortic knob Hilar dance is due to increased pulsations of central pulmonary arteries (Fig 8.16) 2D ECHO is diagnostic and shows paradoxical motion of interventricular septum due to volume overload of RV, interatrial septum is not visualized Color Doppler study helps to deter mine presence and direction of blood flow from interatrial septum crossing LA to RA to RV

Fig 8.16 Chest X-ray large shunt as seen from cardiomegaly and

increased pulmonary vascularity Aorta appears small with normal aortic knob Hilar dance is due to increased pulsations of central pulmonary arteries Multiple black and white spots seen are due to fungus in an old aged film

the derangement in the development of one of these structures:

i Membranous VSD

ii Supracristal or conal VSD

iii Muscular VSD

iv Atrioventricular or endocardial cushion type

It usually manifests after birth when pulmonary pressure

decr-eases and systemic arterial pressure incrdecr-eases with deve lop ment

of L to R shunt

X-ray chest shows variable appearance depending on the

size of the defect It shows cardiomegaly with enlargement of left

atrium, left ventricle and right ventricle Pulmonary artery segment

appears enlarged with increased pulmonary vascularity 2D ECHO

helps to identify and classify the VSD Pressure gradient across the

defect can be determined

Cross-sectional imaging CT and MRI are helpful in com plicated

cases to detect associated vascular anomalies and preoperative

planning

Pneumopericardium

Pneumopericardium is collection of air or gas in the pericardial

cavity Causes of pneumopericardium include blunt or penetrating

chest injuries, respiratory distress syndrome combined with

or without mechanical positive pressure ventilation in infants,

foreign body aspiration, and amebic abscess of the liver Iatrogenic causes included sternal bone marrow puncture, thoracic surgery, thoracocentesis and pericardiocentesis, dental extraction, and laparoscopy Symptoms of pneumopericardium include chest pain, dyspnea, cyanosis, hypotension, bradycardia or tachycardia, and pulsus paradoxus

Posteroanterior view chest helps to distinguish pericardium from pneumomediastinum: A left-side-down decubitus radiograph will show a rapid shift of air in the pericardial sac, while air in the mediastinum will not move in the short interval between films A radiolucent band of air partially

pneumo-or completely surrounding the heart in pneumopericardium (halo sign) and does not extend above the upper limit of the pericardial reflection in the erect position, thus the air is confined below the aortic arch In large pneumopericardium, an enlarged cardiac shadow can be found, CT can demonstrate very small pneumopericardium

Pneumopericardium is rarely associated with existence of air within the spinal epidural space is known as pneu morr hachis

It is usually iatrogenic or associated with trauma and is rare

in asthma This occurs due to lack of fascial wall between the posterior medi astinum and the retropharyngeal and epidural spaces; as a result air can diffuse freely to the epidural space and create pneumorrhachis It is usually asymptomatic A 14-year-old boy suffering from acute exacerbation of bronchial asthma on X-ray chest revealed surgical emphysema with pneumomediastinum and pneumopericardium (Figs 8.17A and B) When subjected to CT scan chest in addition to the findings of the plain film revealed presence of pneumorrhachis

Pulmonary Arterial Hypertension (PAH)

Dyspnea and breathlessness are the main symptom of pulmo nary

hypertension, occurring in more than 95 percent of patients Patients

may also complain of chest pain This can frequently occur on

exertion and radiate to the left shoulder, and may be relieved by rest

Normal pulmonary circulation is a high-flow, low-resistance

circuit capable of accommodating the entire right ventricular

output at one fifth the pressure of the systemic circulation level

The thin-walled right ventricle functions primarily as a

flow-generator pump and is particularly sensitive to increases in its

afterload Increased pulmonary artery pressure and pulmonary

vascular resistance is characteristic pulmonary hypertension

Figs 8.17A and B (A) This 14-year-old boy suffering from acute

exacerbation of bronchial asthma X-ray chest shows pneumo

media-stinum, pneumopericardium and subcutaneous emphysema (arrows)

(B) Axial CT chest shows pneumopericardium (white arrows) and

pneu-m orrhachis (black arrow)

the patient with pulmonary hypertension the mean blood pressure

in the pulmonary artery is greater than 25 mm Hg at rest and 30 mm

Hg during exercise The abnormally high blood pressure is associated with changes in the small blood vessels in the lungs, resulting in an increased resistance to blood flowing through the vessels

Seventy seven years old male had breathlessness for 15 days X-ray chest shows enlarged cardiac silhouette and round upper paracardiac opacities (Fig 8.18A) Main pulmonary artery (MPA) diameter in this case measures 4.5 cm (Figs 8.18A to D) Values for MPA greater than 3.37 cm is suggestive of pulmonary arterial hypertension, when viewed in an unenhanced axial

10 mm section on standard mediastinal window

Figs 8.18A to D CT shows dilated pulmonary arteries because of which upper paracardiac opacities are seen on X-ray chest (A)

A

C

B

D

Aortopulmonary Window

The aortopulmonary window is a small space between the aortic

arch and the pulmonary artery and is visible in the lateral chest

radiograph It contains the ligamentum arteriosum, the recurrent

laryngeal nerve, lymph nodes, and fatty tissue The space is

bounded anteriorly by the ascending aorta, medially by the left

main bronchus, and laterally by mediastinal pleura It is best

demonstrated on CT (Fig 9.1)

Fig 9.1 Axial CT section at the level of aortopulmonary window

showing an enlarged lymph node (arrow)

of the aortopulmonary window They are mainly oval or irregular, less than 10 mm across and sharply delineated from mediastinal fat Lymph nodes in this area are not usually considered sus­picious if they are more than three or a single node exceeds 1 cm

in diameter

Pretracheal Lymph Node

Pretracheal lymph node 1 cm in diameter (Fig 9.2)

Fig 9.2 Axial CT chest at the level of pulmonary artery shows a

pretracheal lymph node

Pneumomediastinum

Pneumomediastinum may result from intrathoracic causes like narrowed or plugged airway, straining against a closed glottis,

blunt chest trauma or extrathoracic causes like sinus fracture,

manipulation in dental extraction, perforation of a hollow viscus

The radiographic signs in pneumomediastinum X­ray show

normal anatomic structures outlined by the air CT confirms the

diagnosis (Figs 9.3A and B)

Pericardial Cyst

Pericardial cyst is a fluid­filled cyst of the parietal pericardium

con sis ting of a single layer of mesothelial cells generally asym­

ptomatic and is an incidental finding, in atypical case of pericardial

cyst chest pain can occur Usually discovered incidentally at 30 to

40 years of age, predominantly in males (3:2) On imaging they are

sharp in outline, round or oval in shape, measuring 3–8 cm in size,

they rarely calcify and on CT their attenuation values are 20–40 HU

They are usually located at the cardiophrenic angle almost always

Figs 9.3A and B (A) Pneumomediastinum (vertical arrows) following

tracheostomy (horizontal arrow) (B) Pneumomediastinum seen as air

lucencies in mediastinum

on the right (Fig 9.4) Differential diagnosis includes pericardial cyst, pericardial fat­pad, sequestration and  Morgagni hernia

Neurogenic Tumors

Neurogenic tumors represent approximately 20 percent of all adult and 35 percent of all pediatric mediastinal neoplasms (Figs 9.5 and 9.6) Neurogenic tumors are the most common cause of

a posterior mediastinal mass Approximately, 90 percent occur in the posterior mediastinum Seventy to 80 percent are benign and approximately half of the patients are asymptomatic

Neurofibroma

Neurogenic tumors are generally grouped into three cate gories: those arising from peripheral nerves, sympathetic ganglia, and parasympathetic ganglia Schwannoma, neuro fibroma and mali­gnant tumor of nerve sheath origin arise from the peri pheral nerves Neurofibromas have low attenuation on CT scans and enhance heterogeneously on postcontrast scans (Fig 9.7) Schw­annomas have attenuation similar to that of muscles on CT scans

Fig 9.4 CT chest axial section at

the level of cardia shows a well­defined rounded to oval lesion in right anterior cardiophrenic angle having mean CT value of 30 HU, the lesion appears to be arising from pericardium

Figs 9.5A and B X­ray chest PA and lateral views show a right well­

defined paratracheal mass on right side without calcification lying in the

posterior mediastinum

Figs 9.6A and B Plain axial CT shows a spherical well­defined soft

tissue mass in right posterior mediastinum with punctate calcific

densities within, in close proximity to T3 and T4 vertebrae measuring

6 x 5 x 5 cm The lesion is seen adjacent to trachea, right main bronchus

and esophagus It shows minimal enhancement on postcontrast studies

and was diagnosed as neurogenic tumor

and enhance mildly with contrast Approximately, 10 percent of nerve sheath tumors grow through the intervertebral foramen into the spinal canal producing a “dumbbell” configuration.

Thoracic Neuroblastoma

Neurogenic tumors are generally grouped into three categories: those arising from peripheral nerves, sympathetic ganglia, and parasympathetic ganglia

Schwannoma, neurofibroma and malignant tumor of nerve sheath origin arise from the peripheral nerves Ganglioneu­roma, gan glio neuroblastoma and neuroblastoma arise from the

Fig 9.7 Mediastinal neurofibroma (arrows)

sym pa thetic ganglia Nerve sheath tumors are most common in

adults while sympathetic ganglia tumors are more common in

children

Neuroblastoma is a malignancy of young children Approxi­

mately 60 percent of cases occur in children younger than 2 years

Two­thirds of children with neuroblastoma are symptomatic,

typically from distant metastases Neuroblastoma manifests

as an elongated to oval paraspinous mass with a propensity

to displace and invade adjacent structures, cross the midline,

and produce extensive skeletal erosion Calcification on X­ray

is seen in approximately 30 percent of cases and 80 percent of

neuroblastomas show calcification on CT

Some neuroblastomas are known to undergo spontaneous

regression (Figs 9.8A and B) or induced differentiation to benign

ganglioneuroma

Figs 9.8A and B (A) Posterior mediastinal mass seen incidentally on

chest roentgeno gram in a 6 weeks old female infant CT chest at the

level of main bronchi demonstrates posterior mediastinal mass 3 x 3

cm seen lifting the left main bronchus and the left pulmonary artery

which is seen as a nipple like small nodule without infiltrations into

the surrounding tissue Histologically confirmed as neuroblastoma

(B) CT scan 3 months later, section at the same level shows marked

spontaneous regression of lesion to 8 mm size

Non­Hodgkin’s lymphoma is much more common than Hodgkin’s disease Non­Hodgkin’s lymphoma is the sixth most common malignancy among males and the fifth most common cancer among females

Both Hodgkin’s disease and non­Hodgkin’s lymphoma can occur in people of any age, but the risk of developing non­Hodg­kin’s lymphoma increases with age, with most patients being diagnosed in their 60s

The symptoms of both types of lymphoma include painless swelling of involved lymph nodes, and further symptoms are dependent upon the location and their extent Hodgkin’s lymphomas are more likely to begin in lymph nodes (Figs 9.9A to C) in the upper body (such as in the neck, underarms, or chest), but both types of lymphoma can be found anywhere in the body Both types of lymphoma may also be associated with general symptoms of weight loss, fever, and night sweats

Both radiation therapy and various chemotherapeutic drugs have been used with success in the treatment of both Hodgkin’s and non­Hodgkin’s lymphoma

Hodgkin’s Disease

Hodgkin lymphoma (Hodgkin’s disease) and non­Hodgkin lymphoma originate in a subset of white blood cells (lympho­cytes), they are an important part of immune system The diff­erence between Hodgkin and non­Hodgkin lymphoma is in the specific lymphocyte involved and these abnormal cells are called Reed­Sternberg cells seen in Hodgkin If the Reed­Sternberg cell is not present, the lymphoma is classified as non­Hodgkin

The distinction is important because the treatment of the two is

different

Hodgkin’s disease occurs most commonly in two distinct age

groups (Figs 9.10A and B) younger people between 15 and 40

years of age (most commonly in the age range of 20–30 years) and

people who are 55 or older at the time of diagnosis

Figs 9.9A to C Show anterior mediastinal lymph nodal mass encasing

the major vessels of the mediastinum in a case of non­Hodgkin’s

lymphoma

A

Thymic hyperplasia usually enlarges the gland but maintains its normal pyramidal shape Thymoma is a lymphoepithelial neoplasm Fifteen to thirty percent are malignant They usually arise in the upper anterior mediastinum, but may project into the adjacent middle mediastinum

CT scan shows a homogeneous density with uniform enhan­cement, invasion of the adjacent structures may be identified with malignant thymomas (Fig 9.11) It may occasionally be cystic

Teratoma

Teratomas (Fig 9.12) comprise of ectodermal, mesodermal and endodermal components Germ cell tumors/teratomas arise from primordial germ cells that undergo aberrant midline

Figs 9.10A and B Contrast CT in a proven case of Hodgkin’s lymphoma shows a large mediastinal lymph node mass There is compression of mediastinal structures including SVC and main pulmonary artery Left pleural calcification is present

cava (white arrow) and left pulmonary artery (black arrow)

Fig 9.12 CT shows a rounded, mixed attenuation enhancing mass

lesion measuring 12 x 10 cm in anterior mediastinum This mass has fat components (asteriks) having attenuation value (–)80 to (–)110 HU, calcific foci of attenuation value 150 to 190 HU (arrow) and soft tissue component with attenuation value of 30 to 45 HU Confirmed as mature teratoma on histopathology

migration during embryologic development They are divided into seminomatous and nonseminomatous tumors and both these groups have benign and malignant varieties

Primary achalasia is the most common subtype and results from the loss of ganglion cells in the esophageal myenteric plexus Secondary achalasia is uncommon and may develop secondary to certain malignancies, diabetes mellitus, and Chagas disease

Clinical features include dysphagia for solids and liquids, regurgitation of food, pneumonia due to aspiration of food, severe retrosternal chest pain in 30–40 percent of patients, weight loss and increased risk for esophageal cancer

Imaging

X-ray chest and abdomen may show air-fluid level in retro cardiac region, nonvisualization of gastric fundic bubble and aspiration pneumonia (Fig 10.1)

Barium swallow shows variable degree of dilation of the esophagus with smooth narrowing at lower esophageal sphincter (Fig 10.2) Distal two-thirds of esophagus may be ape ri staltic

Amol Sasane

Upper GI endoscopy shows undigested food particles along

with ingested fluid filled esophagus and lower end of esophagus

fails to open even after air insufflation

Fig 10.1 X-ray chest an air column on right side behind the heart and great vessels

Fig 10.2 Barium swallow shows dilation of the esophagus (white arrow) proximal to the smooth narrowing at lower esophageal sphincter (black arrow)

of relaxation of lower end of esophagus and pressure at lower end

of esophagus may be high

Endoscopic ultrasound shows thickened muscle layers in the lower part of esophagus

CT scan demonstrates the structural esophageal malities

abnor-Treatment includes:

1 Drugs

i Calcium channel blockers

ii Anticholinergic agents

is considered as early malignancy Barium swallow may show a depressed, polypoid plaque The 5-year survival rate is 70 percent Adenocarcinomas generally spread across the gastroesophageal junction to involve the gastric fundus

Early detection remains the goal of research Only surgical resection at a very early stage has shown improved survival rates For the purpose of staging esophageal carcinoma contrast-enhan-ced CT offer unique information (Figs 10.3 and 10.4) Limitation

Fig 10.3 CT shows prestenotic dilatation of esophagus with air fluid

(contrast) level (arrow)

Fig 10.4 CECT chest shows circumferential wall thickening of mid

esophagus with loss of fat planes with bronchus, pulmonary artery and

aorta The esophageal lumen is narrowed (arrows)

size criteria is used to determine possible metastatic involvement; however, lymph nodes may be enlarged because of infectious or inflammatory etiologies Conversely, subcentimeter lymph nodes may harbor metastatic tumor.

Holt-Oram Syndrome

HoltOram syndrome is an inherited disorder that causes abnor

-malities of the hands, arms, spine and heart Occurs approximately

one in every 1,00,000 and affects both sexes equally

It falls into two groups: (1) Defects in arm and hand bones

involv-ing one or both sides of the body Most commonly the defects are

in the carpal bones and thumb The thumb may be malformed

or missing In severe cases the arms may be very short such that

the hands are attached close to the body (phocomelia) (2) Heart

abnormalities—three-forths of cases with Holt-Oram syndrome

have heart abnormality It may be abnormal rhythms, atrial or

ventricular septal defect (Figs 11.1A to D)

Tracheoesophageal Fistula

The trachea and esophagus develop from the common foregut

during early first trimester Incomplete separation results in

esophageal atresia with or without associated tracheoesophageal

fistula (T-E fistula)

The T-E fistula occurs one in every 3,000 to 5,000 live births

The neonate usually present with choking while feeding, cough,

cyanosis, recurrent pneumonia A nasogastric tube cannot be

passed into the stomach On X-ray abdomen, it is gasless and may

be scaphoid

Classification of T-E Fistula (Figs 11.2A to E)

Type A: Esophageal atresia without fistula

Type B: Esophageal atresia with proximal T-E fistula

Type C: Esophageal atresia with distal T-E fistula

Type D: Esophageal atresia + proximal and distal T-E fistula

Type E: Tracheoesophageal fistula without atresia

Fifty percent of cases are associated with VACTERL bral, anorectal, cardiac, tracheoesophageal fistula, renal and limb anomalies) syndrome

(verte-Chest radiograph immediately after birth reveals distended proximal esophageal pouch with round distal margin and coiled nasogastric tube within the esophageal pouch is diag no stic The presence of air in the stomach and small bowel indicates eso-phageal atresia with a distal tracheoesophageal fistula Absence

of air in the stomach eliminates the possibility of a distal fistula

Figs 11.1A to D (A) and (B) X-ray spine show multiple spinal anomalies (C) Shows congenital heart disease (VSD) (D) Shows absence of radius All these are features

of Holt-Oram syndrome

C B