Value of brominated fluorocarbons for the radiographic diagnosis of small-bowel obstruction: comparison with other contrast agents in rats.

OBJECTIVE: The disadvantages of water-soluble gastrointestinal contrast agents include high osmolality, contrast dilution, and severe toxicity if aspirated. Perfluorocarbons are nontoxic in the lung and peritoneal cavity. Because perfluorocarbons are immiscible with water, they have no osmotic effect and cannot be diluted. Because these properties offer theoretical advantages over traditional gastrointestinal contrast agents, we compared two perfluorocarbons with barium and ionic and nonionic iodinated contrast material in a rat model of small-bowel obstruction. MATERIALS AND METHODS: Twelve groups of six rats each had ligation of the terminal ileum (obstruction model) or of the terminal ileum and mesenteric artery (obstruction with ischemia model). Each rat received 3 ml of barium, meglumine sodium diatrizoate, iohexol, neat perfluorooctyl bromide, neat perfluorohexyl bromide, or saline (control animals). Contrast media were given at the recommended concentrations, and their progression was evaluated on serial radiographs by an observer who was not aware of the model or the contrast medium given. When one contrast material reached the point of obstruction, all rats in the group were sacrificed and a final radiograph was obtained. Three radiologists, who were not aware of the contrast medium given, on two separate occasions independently reviewed the radiographs and ranked the contrast agents for their relative radiopacity, mucosal definition, speed of transit, gastric retention, and bowel distension. RESULTS: When data from both models were combined, perfluorocarbons were judged on the final image to be the most radiodense, to provide the sharpest mucosal detail, to have the least gastric retention, and to have faster progression than barium. Whereas meglumine sodium diatrizoate and iohexol reached the point of obstruction more rapidly than the perfluorocarbons and barium, they had the greatest gastric retention, caused the most bowel distension, and were the least radiopaque. CONCLUSION: Our results show that the radiopaque perfluorocarbons are suitable as gastrointestinal contrast agents and have favorable radiographic characteristics in this animal model. When these results are combined with the low-toxicity profile of perflubron, clinical evaluation of this agent for the radiographic assessment of bowel obstruction is warranted.

Women's attitudes toward screening mammography.

Although mammography has been proven an effective tool in screening asymptomatic women, it has been underused because of poor physician and patient compliance. At a university mammography clinic in Southern California, we administered questionnaires to 381 asymptomatic women to determine what women perceived to be incentives and deterrents to mammography. A factor analysis grouped the incentives into five factors, in decreasing significance: "doctor's recommendation," "personal experience," "media," "others' recommendation," and "breast symptoms." Similarly, we grouped the deterrents according to five factors, in decreasing significance: "cost," "fear of medical intervention," "unnecessary screening," "time demands," and "transportation difficulties." We compared the relative significance of these incentive and deterrent factors for demographics, aspects of the doctor-patient relationship, and individual characteristics. Younger, married women rated incentives, particularly "personal experience," higher and deterrents lower in general than older, unmarried women who had more concerns about "cost." However, all demographic groups rated "doctor's recommendation" as the highest incentive, and we found few differences among races or socioeconomic status for any factor. Women whose physicians had initiated the discussion of mammography viewed the doctor's recommendation as a greater incentive than women who had to initiate the discussion about mammography. Women under the care of gynecologists saw the doctor's recommendation as a greater incentive than women under any other specialists' care. Gynecologists initiated the discussion of mammography and recommended screening more often than other specialists. Women with the following individual characteristics identified more incentives to mammography: knew someone with breast or other cancer, estimated themselves to be at high risk for breast cancer, or had at least one previous mammogram.(ABSTRACT TRUNCATED AT 250 WORDS)

Real-time breast sonography: application in 300 consecutive patients.

Sonography, disappointing as a primary screening method, has emerged as the single most helpful adjunct to mammography in evaluation of the clinically and/or mammographically abnormal breast. Sonography can reliably diagnose simple cysts presenting as palpable masses or as indeterminate, nonpalpable lesions on mammography. However, differentiation of benign from malignant solid masses cannot be reliably accomplished by sonography. The expense of an automated breast sonographic scanner has deterred many radiologists from the purchase of such a unit. The authors have used both an automated breast scanner and a real-time 10-MHz hand-held unit. This paper describes their experience with the real-time unit, demonstrating both normal and pathologic anatomy. Special emphasis has been placed on the sonographic diagnosis of a simple cyst because this lesion was the cause of one-quarter of all palpable masses and nonpalpable, mammographically dominant masses. Cysts are sharply marginated and anechoic. Posterior enhancement visible in 78 of 80 cysts was not demonstrable on all images in 25% of cysts.

Respiratory distress syndrome treated with human surfactant: radiographic findings.

Chest radiographs of 18 newborns treated with endotracheal instillation of human surfactant for respiratory distress syndrome (RDS) were compared with those of 18 similar but untreated infants. In the treated infants, severity of RDS significantly improved after surfactant administration. Most treated infants (16/18) exhibited a left-to-right shunt, presumably through a patent ductus arteriosus; similar findings were noted in untreated infants (17/18). Complications of respiratory assistance in the treated infants included transient pulmonary interstitial emphysema (n = 1), pneumothorax (n = 1), and mild (n = 4) to moderate (n = 2) bronchopulmonary dysplasia; the incidences of these complications did not exceed those in untreated infants. In three treated infants, a transient interstitial lung disease developed 3-4 days after surfactant administration.

Comparison of high resolution real time ultrasonography and high resolution computed tomography in an infant with spinal dysraphism.

An infant with a lumbosacral spinal subcutaneous and intraspinal lipoma involving the conus medullaris was studied with computed tomography and high resolution real time ultrasonography to determine the extent and location of the disease before operation. The high resolution ultrasonogram demonstrated the abnormality with good detail and the added advantage of real time display of the lack of pulsatile mobility of the neural elements, confirming spinal cord tethering. Spinal high resolution ultrasonography is a noninvasive diagnostic tool in infants with spinal abnormalities and should be an important part of a neurosurgeon's diagnostic support system.

Occult spinal dysraphism in infants: screening with high-resolution real-time ultrasound.

Spinal dysraphism refers to incomplete embryologic development of the dorsal midline. Frequently it is not clinically obvious, and lack of treatment can lead to progressive neurological damage. Early diagnosis of occult defects can allow appropriate surgical intervention and prevent neurological deficits. The authors have used high-resolution real-time ultrasound to screen infants with various cutaneous lumbosacral markers, all of whom were at risk of occult spinal dysraphism. Preliminary results suggest that ultrasound is a reliable screening procedure and could obviate the need for more costly and invasive tests.

Low-dose radiography of children.

During the past five years, over 50,000 routine examinations in pediatric radiology have been performed utilizing a high-speed, rare-earth system. A detailed study of the physical characteristics as well as subjective qualities of all of the commercially available rare-earth systems was performed. Our extensive clinical experience with a gadolinium oxysulfide system is described in detail. Practical points on how to avoid certain pitfalls when instituting a system of low-dose radiography are discussed. The present system allows a significant reduction in radiation dosage with maintenance of fine to excellent radiographic resolution.