Alexandria Radiology » Chest

Chest Case 15

anne — Tue, 17 Nov 2009 16:24:15 +0000

Chest radiographs are normal in more than half of patients with H1N1. The typical pattern when present is one of bilateral alveolar disease with lower and central lung preponderance. Small pleural effusions have also been described. Follow up radiographs usually show waxing and waning of alveolar disease. Agarwal et al. have recently shown that CT was more sensitive than plain radiographs (AJR oct 2009). The CT scans showed a combination of ground glass opacities and consolidation in most patients. The distribution was diffuse without zonal predominance in seven patients.

Pulmonary emboli were also identified on CT but determined not to be related to H1N1.

Chest Case 14

anne — Tue, 01 Sep 2009 11:48:05 +0000

Lymphangioleiomyomatosis (LAM) is a rare disorder resulting from proliferation of smooth muscle cells along lymphatics in lung, thorax and abdomen. The etiology of the disease is unknown. The disorder affects young patients with female predominance. It presents with spontaneous pneumothorax, chylothorax, hemoptysis, and slowly progressive dyspnea. Similar lesions may be seen in tuberous sclerosis (Some suggest LAM is a forme frust of tuberous sclerosis). Extrapulmonary LAM is rare.

Radiographically presents with numerous thin walled cysts, 90 percent with size of cysts < 5-10 mm. Recurrent pneumothotax, 70 percent. Chylous pleural effusions, 25 percent.

Chest Case 13

anne — Mon, 13 Jul 2009 16:39:14 +0000

Elastofibroma is a benign pseudotumoral reactive fibrous lesion of the chest wall likely secondary to chronic mechanical friction between the tip of the scapula and the chest wall. Characteristically located between the chest wall and the inferior tip of the scapula, but 5% of elastofibromas are found elsewhere. Most lesions are asymptomatic. Bilateral lesions are common but are often asymmetric. CT shows a mass with soft-tissue attenuation with striations of fat attenuation. On MR imaging, elastofibroma is a poorly circumscribed semilunar, heterogeneous soft-tissue mass, with signal intensity similar to that of skeletal muscle interlaced with strands of fat. Surgery is curative; recurrences (7%) are probably caused by incomplete excision.

Chest Case 12

anne — Mon, 13 Jul 2009 14:52:28 +0000

The incidence of primary neurogenic tumor of the lungs to be 0 to 2%. Likely originating from schwann cell and predominantly associated with neurofibromatosis. The diagnosis of intratracheal tumors is usually made by endoscopy. However, although the findings are not specific, CT scanning and magnetic resonance imaging (MRI) are increasingly used to delineate tumor size and extension as well as associated parencymal changes.

Chest Case 11

anne — Mon, 13 Jul 2009 14:48:08 +0000

Spindle cell carcinoma (SCC) is a rare form of lung cancer representing 0.2 to 0.3% of all primary pulmonary malignancies. More frequent in male than female and in smoker than nonsmoker with an age range between 50 to 80 years old. Pathologically contains malignant epithelial and sarcomatous elements. Considerable controversy regarding hystogenesis of these lesions exists.

Radiographic features of these lesions are often nonspecific warranting soft tissue sampling for further characterization.

Chest Case 10

anne — Mon, 13 Jul 2009 14:40:52 +0000

Pulmonary tuberculosis is caused by the bacteria Mycobacterium tuberculosis (M. tuberculosis). Radiographic screening for active TB in high-risk populations may demonstrate findings consistent with prior and/or current infection. A Ghon focus refers to the initial site of parenchymal involvement at the time of first infection; a Ranke complex is the combination of a Ghon focus and enlarged or calcified lymph nodes; and Simon foci are apical nodules that are often calcified and result from hematogenous seeding at the time of initial infection.

On a single screening chest radiograph, detection of any abnormality—parenchymal, nodal, or pleural—with or without associated calcification, should result in an interpretation of indeterminate disease activity. Radiographic differentiation between active and inactive disease can only be reliably made on the basis of temporal evolution. Lack of radiographic change over a 4- to 6-month interval generally indicates inactive disease.

Primary disease
Lymphadenopathy is the radiologic hallmark of primary TB. On contrast material–enhanced computed tomographic (CT) scans, mediastinal tuberculous lymphadenitis, particularly when nodal size exceeds 2 cm in diameter, may have a characteristic appearance consisting of central areas of low attenuation. Although the appearance is very suggestive, it is not pathognominic. Differential include: atypical mycobacterial infection; lymphoma; metastases, particularly from testicular carcinoma; and benign conditions such as Whipple and Crohn diseases.

Parenchymal opacities typically an area of homogeneous consolidation occur in association with and affect the same side as nodal enlargement in approximately two-thirds of pediatric cases of primary TB.

Pleural effusion is an uncommon manifestation of primary TB in infants and young children (<2 years of age) (32). The prevalence of effusion increases with age and is reported to be 6–11% in children (58,59) and 29–38% in adult

Postprimary disease
Parenchymal opacities situated in the apical and posterior segments of the upper lobes and the superior segment of the lower lobes, often associated with cavitation, are the characteristic radiographic manifestations of postprimary TB.

Parenchymal involvement occurs in more than one segment in the majority of cases. Cavitation in single or multiple sites is evident radiographically in 40%–45% of cases of postprimary TB (66,78). Walls of cavities may range from thin and smooth to thick and nodular. Hilar and mediastinal lymphadenopathy are uncommon manifestations of postprimary TB and occur in only approximately 5% of cases. Tuberculous pleural effusion, although usually regarded as a manifestation of primary disease, may occur in association with postprimary disease in up to 19% of detected cases.

Chest Case 9

anne — Mon, 13 Jul 2009 14:37:52 +0000

Extramedullary hematopoiesis refers to the location of hematopoietic elements in locations other than the bone marrow medullary space most often seen in chronic anemias. Most often, it is microscopic and asymptomatic, but it can manifest as organomegaly and tumor-like masses. Intrathoracic EMH usually presents as paraspinal masses and can be confused with neurogenic tumors, lymphoma, metastasis, paravertebral abscess, and lateral meningocele. Associated bone changes manifested by marrow expansion, cortical thinning and trabecular rarefaction are often present. These lesions are usually slow-growing and do not cause any significant bone erosion. Chronic, inactive lesions may reveal iron and/or fatty deposition. Radionuclide imaging with technetium-99m sulfur colloid may reveal extrahepatosplenic uptake of colloid. Fine-needle biopsy can confirm the diagnosis.

Chest Case 8

anne — Mon, 13 Jul 2009 13:40:26 +0000

Aortic intramural hematoma (IMH) is related but is pathologically a different entity from aortic dissection, characterized by hemorrhage into the aortic media without an intimal tear. Although intimal disruption is not present, the prognosis is similar to that of classic aortic dissection and both are potentially lethal.

IMH is difficult to distinguish from classic dissection on purely clinical grounds. IMH has a variable clinical course. While some patients have limited hemorrhage and respond well to medical therapy, IMH may progress to classic dissection.

Lacking data from clinical trials, treatment of IMH has been mostly empiric. Most authorities currently recommend treatment of IMH similar to that of classic aortic dissection.

Chest Case 7

anne — Mon, 13 Jul 2009 13:38:08 +0000

Poland syndrome is a rare birth defect characterized by underdevelopment or absence of chest wall muscles (pectoralis major and/or minor) as well as webbing of the fingers. The precise cause for Poland syndrome is largely unknown. Geneticists currently hold that Poland syndrome is rarely inherited and generally is a sporadic event.

There is variation in expression of the physical changes among patients. Common features include:

underdevelopment or absence of the pectoralis
the end of the pectoralis muscle attachment to the breastbone (sternum) is absent
the nipple, areola, and (in females) underlying breast tissue is underdeveloped or absent
short and webbed fingers (cutaneous syndactyly) on the effected side
armpit hair on the effected side is missing

Chest Case 6

anne — Mon, 13 Jul 2009 13:35:19 +0000

The azygos system is a paired paravertebral venous pathway in the posterior thorax. The azygos vein originates at the junction of the right ascending lumbar and subcostal veins, enters the chest through the aortic hiatus, and ascends along the anterolateral surface of the thoracic vertebrae At T5-T6. It arches ventrally just cephalad to the right main bronchus and drains into the SVC. Similar to the azygos vein, the hemiazygos vein originates at the junction of the left ascending lumbar and left subcostal veins and often receives tributaries from the left renal vein and inferior vena cava (IVC).

These anomalies may be isolated or associated with other anomalies. The incidence in patients with congenital heart disease undergoing cardiac catheterization ranges from 0.2 – 1.3 percent. Azygos continuation is common in patients with polysplenia (left isomerism) but rare in patients with asplenia (right isomerism). Other associated anomalies include abnormal abdominal situs and a left or duplicated IVC. The imaging features of azygos continuation of the IVC include dilatation of the azygos vein, azygos arch and SVC caused by increased flow. The hepatic veins drain into the right atrium via the suprahepatic IVC. The hepatic segment of the IVC is absent or hypoplastic, and this condition must be documented to exclude other causes of an enlarged azygos vein. Azygos continuation has also been reported in association with an azygos lobe.