Breast skin thickness: normal range and causes of thickening shown on film-screen mammography.

We measured breast skin thickness on the film-screen mammograms of 250 asymptomatic women and found a normal range of 0.7-2.3 mm in the superior quadrant and 0.7-2.7 mm in the inferior quadrant as measured on the mediolateral view and 0.6-2.4 mm in the medial quadrant and 0.5-2.1 mm in the lateral quadrant as measured on the craniocaudad view. In our experience a skin thickness of greater than 2.5 mm suggests the presence of disease. Causes of skin thickening in our series of 44 patients included carcinoma, metastases, post radiation therapy, post surgery, infection, and anasarca. Other reported causes are trauma, fat necrosis, dermatologic conditions, and lymphoma.

Pulmonary sequestration: visualization of the feeding artery by CT.

Pulmonary sequestration (PS) is a relatively uncommon anomaly that usually requires invasive procedures such as arteriography for definitive diagnosis. We recently encountered a case in which the diagnosis of PS was strongly suggested by the findings on computed tomography (CT). Subsequently, an intralobar sequestration was found at surgery without the aid of a prior arteriogram. We feel that CT may have a definitive role in the radiological workup of suspected cases of PS.

The neonate with adult-type autosomal dominant polycystic kidney disease.

A premature infant with severe respiratory distress syndrome was found to have bilaterally enlarged kidneys and normal renal function. Renal ultrasonography confirmed renal enlargement but revealed no hydronephrosis or cysts. Family history was consistent with autosomal dominant polycystic kidney disease (ADPKD), and renal ultrasonography in the mother revealed bilateral multiple cysts of which she was previously unaware. The infant died of respiratory failure and septicemia, and autopsy revealed multiple microscopic renal cysts characteristic of early ADPKD. This case, along with 16 other affected newborns previously reported, illustrates the difficulty and importance of diagnosing ADPKD in the neonate. It is anticipated that awareness of this unusual cause of renal enlargement in the newborn will result in earlier diagnosis and appropriate genetic counselling.

Limitations of ultrasonography in evaluating patients with jaundice or cholecystectomy.

Abdominal ultrasonography has been shown to accurately distinguish medical (nonobstructive) jaundice from surgical (obstructive) jaundice. As occurs commonly with a new diagnostic procedure, initial evaluations are enthusiastic and emphasize the positive features of the technic. When further experience with the procedure is acquired, its negative features are recognised and reported. We review our experience and that of others to stress the limitations of ultrasonography and the potential for misinterpretation of its findings when evaluating the biliary tract in patients with jaundice or postcholecystectomy biliary colic. The applications of computed tomography and cholescintigraphy are briefly and critically evaluated in this same patient population. The role of sonography as a screening procedure and the findings that indicate the need to proceed to other imaging technics are examined. Finally, we describe our criteria for choosing the next step in the diagnostic evaluation--intravenous, percutaneous transhepatic, or endoscopic retrograde cholangiography.

Neonatal urinary ascites secondary to distal ureteral stenosis.

We report a case of neonatal urinary ascites secondary to distal ureteral stenosis. We believe that this is the first reported case of urinary ascites secondary to distal ureteral stenosis with a normal contralateral kidney and ureter.

Nuclear scintigraphy and ultrasound in the diagnosis of congenital ureteropelvic junction obstruction.

Congenital ureteropelvic junction obstruction is well known. The traditional mainstay of diagnosis has been excretory urography. However, in the neonatal period ultrasound and renal scintigraphy should be the initial diagnostic procedures for this disease. Excretory urography may be tailored or eliminated using these 2 tests as guides. We report a case of bilateral ureteropelvic junction obstruction diagnosed in utero and suggest a diagnostic study, stressing the liabilities of excretory urography in the neonate or young child.

In utero diagnosis of multicystic kidney disease by sonography.

Multicystic kidney, one of the more common renal anomalies presenting in the newborn period, can be diagnosed in utero sonographically. The sonographic differentiation among the varied renal cystic disease is briefly discussed and the utility outlined.

Choledochal cyst: sonographic evaluation of an unusual case.

The preeminence of sonography in the diagnosis of obstructive jaundice has already been established. Earlier reports have described a variety of radiologic modalities used to establish the diagnosis of choledochal cyst. Our case illustrates the usefulness of sonography in differential consideration, though either transhepatic or operative cholangiography is necessary to further define the point and nature of the obstructive process and to determine that the cyst communicates with the common bile duct.

Distended left renal vein: CT/sonographic normal variant.

The left renal vein frequently demonstrates a marked variation in caliber between the part distal to the aorta and the part directly in front of the aorta. This is well seen on both computed tomography (CT) and sonography. This variation in caliber or distention is believed to be secondary to a "nutcracker " effect formed by the aorta posteriorly and the superior mesenteric artery anteriorly. The third part of the duodenum may also add to the pincer effect on the left renal vein. A series of 72 patients was examined for this variation and the relation of the caliber of the left renal vein to the anatomy of the aorta, superior vena cava, and duodenum. These patients were also evaluated for any possible relation between the presence of a distended left renal vein and a varicocele.

Sonographic diagnosis of cholelithiasis in childhood.

With the development of new gray scale signal processing, a high level of accuracy has been obtained with gallbladder sonography. Biliary calculi seem to be more prevalent in the pediatric population than is generally appreciated. Two interesting features of childhood cholelithiasis are the increased incidence in patients without hemolytic anemia and the uncommonly high percentage of gallstones visible with plain roentgenograms of the abdomen. Cholecystosonography is offered as an additional method of establishing diagnostic certainty.

Falciform ligament: varieties of imaging experience.

The falciform ligament is commonly imaged by various modalities available to most radiologists. When displayed, its diagnostic value is limited, but knowledge of its appearance as encountered on different examinations is useful, lest pathologic significance be applied to its appearance.

Sonography of benign sacral teratoma in utero.

Sacral teratoma is rarely diagnosed in utero. In the case presented, gray-scale sonography revealed a teratoma in utero, demonstrated the proportion of solid and cystic components, and identified calcification. These are important features, since solid tumors lacking calcification are usually malignant, and cystic or complex tumors as well as those with calcification are usually benign.