Jack L. Westcott

Interstitial Pulmonary Emphysema in Children and Adults: Roentgenographic Features

Chest films of 12 patients ranging in age from 3 to 55 years with autopsy-verified interstitial pulmonary emphysema (IPE) were reviewed. All had received positive pressure breathing. Opacification of the lungs due to edema, hemorrhage, or pneumonia often made IPE visualization possible. Diagnostic radiographic features include direct visualization of interstitial air, and the appearance of subpleural air cysts formed by continued dissection of interstitial air into the subpleural connective tissues. Recognition of IPE is of importance because it may directly impair pulmonary ventilation and perfusion and may be followed by development of pneumomediastinum, pneumothorax, and secondary infection.

Dissecting hematoma of the aorta secondary to blunt chest trauma.

Two types of dissecting aortic hematoma occasionally follow blunt chest trauma. Localized subadventitial dissecting may occasionally accompany aortic laceration or transection. This subadventitial hematoma may itself rupture, or it may compress the true aortic lumen. In the presence of arteriosclerosis, classical (medial) dissecting hematoma may occur following blunt trauma. The trauma may be considerably less than that required to cause aortic rupture. Differentiation of the two forms may have practical significance. The treatment of aortic laceration is surgical repair, whether or not there is an associated subadventitial dissection. However, medial dissection following trauma is indistinguishable from spontaneous aortic dissection, and medical therapy may sometimes be the preferred method of treatment.

Cecal herniation through the foramen of Winslow.

Two cases of foramen of Winslow hernia are presented and characteristic upper gastrointestinal findings are discussed. A diagnosis of cecal herniation can be made if there is (a) a collection of gas or gas and fluid in the lesser sac, displacing the stomach anteriorly and to the left, (b) failure to visualize the cecum in its usual position, and (c) displacement of the first and second portions of the duodenum to the left. This last finding is especially helpful in differentiating a foramen of Winslow hernia from a lesser sac abscess.

Intra-arterial lidocaine: an effective analgesic for peripheral angiography.

Intra-arterial lidocaine was found to be an effective and safe method for reducing pain associated with peripheral angiography. A convenient method for delivery is to directly mix 2% lidocaine and contrast material in a ratio of 1:10 by volume. In a comparative evaluation, 25 of 29 patients experienced significantly less discomfort when the lidocaine-contrast mixture was used as compared to contrast material alone. There were no apparent complications from the use of intra-arterial lidocaine.

Pulmonary Lesions Due to Dirofilaria immitis (Dog Heartworm)

Chest radiographs of 4 patients with Dirofilaria immitis (dog heartworm) revealed solitary, small, peripheral, noncalcified nodular lesions. The pulmonary lesions were apparently produced secondary to lodging of the parasite in peripheral pulmonary vessels. None of the patients had symptoms referable to the heartworm lesions. Needle aspiration in 2 patients revealed a nonspecific inflammatory lesion.

Lipoma of the Diaphragm: Report of a Case

A lipoma of the diaphragm was found at surgery in a 69-year-old man. Postmortem examination offered an unusual opportunity for radiological/pathological correlation. Diaphragmatic lipomas are usually asymptomatic and present radiographically as smooth, rounded masses which generally arise from the posterolateral portion of one hemidiaphragm. They may appear less radiopaque than would be expected of a lesion that size. Certain features of this case suggest that the lipoma may have been the result of chest trauma.

Mesentery and Colon Injuries Secondary to Blunt Trauma

Three cases of colon lesions following blunt trauma are presented to illustrate their varied manifestations. Although these injuries are not as common as those to the small bowel and solid viscera, the radiologists awareness of them and of their various presentations may be helpful in suggesting the correct diagnosis. The major types of colon injury include mesenteric laceration with blood loss, vascular injury with or without bowel ischemia, intramural hematoma, bowel wall laceration, and delayed cicatricial stenosis.

Pulmonary Edema and Respiratory Insufficiency in Acute Pancreatitis

Pulmonary edema, cardiac enlargement, and respiratory insufficiency may occur in patients with acute pancreatitis. The mechanisms are complex and incompletely understood, but probable etiologic factors include fluid overload, left ventricular failure, impaired respiratory excursion and microatelectasis, and a nonspecific response of the lung to various types of pulmonary injury including hypotension, intravenous crystalloids, and the effects of circulating pancreatic enzymes. Recognition of the association of pulmonary edema and respiratory insufficiency with pancreatitis is importance because early treatment with positive pressure breathing, careful fluid management and diuretics, and corticosteroids may prevent the development of irreversible respiratory failure.

Cardiopulmonary effects of intravenous fluid overload: radiologic manifestations.

Large volumes of normal saline were infused intravenously in 6 dogs until obvious pulmonary edema was observed radiographically. Following volume overload, statistically significant increases occurred in the size of the heart, left atrium, pulmonary arteries and veins, and systemic veins, without the development of congestive heart failure (CHF). The left ventricular end-diastolic pressure remained normal, and cardiac output and stroke volume increased. The results suggest that, in the absence of left ventricular failure, acute volume overload may simulate the radiographic changes produced by CHF. Pulmonary edema may have occurred at least partly from a marked decrease in serum colloid osmotic pressure.

The right pulmonary artery-left atrial axis line. A method for measuring left atrial size on lateral chest radiographs.

Based on the relationships of the aorta, right pulmonary artery (RPA), and left atrium (LA), a method for directly measuring the LA diameter is described. A line drawn downward from the anterior wall of the RPA, parallel to the barium-filled esophagus, will approximate the anterior wall of the LA and enable a direct measurement of the anteroposterior LA diameter. This radiological measurement correlated well with the echocardiographic determination of LA size in 82 adult patients. In some patients, direct measurement of LA size made it possible to detect chamber enlargement before other signs appeared. The major disadvantage of this method is the inability to clearly see the RPA in infants and in approximately 10-15% of adults.