The present status of imaging of the gallbladder.

Oral cholecystography is still the basic modality for the diagnosis of gallbladder disease. Now, for the first time since the introduction of this procedure in 1924, this status is being challenged by another diagnostic technique, ultrasonography of the gall bladder. Ultrasound studies have major advantages over conventional cholecystography. These are sufficiently important that it can be safely predicted that ultrasonography will eventually become the primary diagnostic tool for evaluating the gallbladder. Just as the use of colonoscopy has provoked a new analysis of the barium enema examination in the evaluation of the colon, the introduction of ultrasound examination of the gallbladder has revealed the fact that false-negative oral cholecystograms are not rare. Before ultrasonography this information was unobtainable, because of the surgeon's proper reluctance to perform a cholecystectomy in patients with normal oral cholecystograms. Indeed, the availability of an accurate alternate diagnostic procedure has stimulated a reevaluation of other difficulties associated with oral cholecystography. These include problems involved with non-visualization and impaired visualization of the gallbladder after a single dose of contrast material, misunderstandings concerning the uses of oral cholecystography compared to those for intravenous cholangiography and uncertainty regarding the value of cholecystokinin cholecystography in the diagnosis of acalculous cholecystitis. Knowledge of the pharmacokinetics of the oral cholecystographic contrast agents has been long overdue, considering the extensive use of these compounds in clinical practice for more than 50 years. However, information on this subject has finally reached a stage where the data can be applied to ensure that cholecystography is done with maximun efficiency and safety and with the least radiation exposure. The purpose of this report is to review the problems involved with imaging of the gallbladder by oral cholecystography and to discuss the indications, interpretation and accuracy of gallbladder imaging with ultrasonography. Data concerning the use of computerized tomography for evaluation of the gallbladder are still preliminary but are discussed.

Growth rates of small abdominal aortic aneurysms.

A policy of utilizing B-mode ultrasound scan measurements of abdominal aortic aneurysms to help determine operability in poor-risk patients with small asymptomatic aneurysms has been pursued for the past 6 years. Indications for surgery in such patients have included enlargement to 6 cm. in any transverse diameter, the development of symptoms, or evidence of leak or rupture. In addition, patients treated nonoperatively have been followed by serial B-mode echo scans, permitting the accumulation of aneurysm growth rate data. Such data indicate that small aneurysms grow an average of 0.4 cm. per year, but that dramatic increases in aneurysm size may occur unexpectedly in asymptomatic patients. These data appear to have value in both individual decision making and as a baseline for weighting the various risk factors in the poor-risk patient with a small asymptomatic abdominal aortic aneurysm.

The reliability and predictive value of an amniotic fluid scoring system in severe second-trimester oligohydramnios.

Sixty-two cases of oligohydramnios diagnosed by ultrasound between 13-28 weeks' gestation were reviewed. Three experienced ultrasonographers used a subjective scale to rate the oligohydramnios as mild, moderate, severe, or anhydramniotic. Interobserver reliability was excellent (intraclass correlation coefficient 0.81). The overall perinatal mortality rate was 43%, and the incidence of pulmonary hypoplasia was 33%. One-third had lethal congenital anomalies. The frequency of adverse outcome correlated strongly with the most severe degrees of oligohydramnios; 88% of the fetuses with severe oligohydramnios or anhydramnios had lethal outcomes, compared with 11% in the mild/moderate group. The presence of an anuric urinary tract anomaly was associated with the most severe grades of oligohydramnios and was uniformly fatal. Pulmonary hypoplasia was diagnosed in 60% of the severe group versus 6% in the moderate group. We conclude that subjective grading of oligohydramnios by experienced observers is both reliable and predictive of outcome. The finding of severe oligohydramnios in the second trimester is highly predictive of poor fetal outcome and should stimulate a thorough search for etiology and consideration of intervention. Moderate grades of reduced amniotic fluid may be managed with relative optimism.

Diagnostic imaging in head and neck disease: current applications of ultrasound.

Diagnostic ultrasound has become firmly established as a key imaging modality in obstetrics and gynecology. Its role in abdominal and retroperitoneal disease is also well known and continues to expand. Although usage of ultrasound in the head and neck had its beginnings many years ago, the advent of newer high-resolution transducers has allowed for further investigation of diseases in this area. Of particular interest are the thyroid gland and the extracranial carotid arteries. This review summarizes the current utility of gray-scale and real-time ultrasound in evaluating head and neck disease, and discusses potential future applications of the modality.

Induction of ovulation and pregnancy with pulsatile luteinizing hormone releasing factor: dosage and mode of delivery.

The efficacy of intravenous and subcutaneous routes for pulsatile delivery of differing dosages of synthetic luteinizing hormone releasing factor (LRF) for ovulation induction were evaluated sequentially in two patients with presumed deficiency of endogenous LRF: isolated gonadotropin deficiency and pituitary stalk transection with hyperprolactinemia. Observations were made of the amplitude and duration of the induced LH-FSH pulses, of follicular growth and ovulation (via ultrasound), and of ovarian steroids. Remarkable differences in each of these parameters were found between the two modes of LRF delivery. LRF pulses administered subcutaneously resulted in inappropriate gonadotropin secretion, arrest of follicular development, elevated ratios of E1/E2 and androgens/estrogens, and the appearance of acne - features of polycystic ovary syndrome. In contrast, the first intravenous course of pulsatile LRF induced orderly follicular maturation and ovulation with subsequent pregnancy in both subjects. From these findings we conclude that, in these patients, the intravenous mode of delivery of LRF pulses was superior to the subcutaneous route at all doses tested.

Ultrasonography of jaundice.

Ultrasonography is proposed as a valuable first step in the study of the jaundiced patient. Utilizing modern gray scale technology, it is nearly always possible to determine whether or not dilatation of the biliary tree is present. In the presence of diffuse liver disease without obstruction, some assessment of the state of the parenchyma can often be made. In patients with obstruction, its severity and level are usually easy to determine. It may be considerably harder to correctly diagnose the etiology of the obstruction, and more invasive investigations will then be required.

Ultrasonic imaging of the carotid arterial system.

The ability of a B-mode, real-time, high frequency ultrasonic imager to diagnose carotid arterial disease was evaluated in 81 carotid arteries. The imager was relatively sensitive in detecting the presence of significant stenosis but was relatively insensitive in its ability to quantitate the degree of stenosis. The imager was unable to detect the presence of ulcerations. The oculoplethysmograph had a greater sensitivity, specificity and accuracy than the ultrasonic imager in diagnosing carotid arterial stenosis in the same group of patients. Ultrasonic imaging appears to be useful as a screening test of cerebrovascular disease when used in combination with the oculoplethysmographic test.

Sonography of gallstones and biliary dilatation without a visible aetiology: the infrequency of obstructing choledocholithiasis.

This paper describes 50 consecutive patients who sonographically had gallbladder stones and dilated bile ducts, but no visible aetiology for the dilatation. We reviewed these cases to determine the frequency of choledocholithiasis in this setting. Common duct stones caused obstruction in only 36% of these patients. Other aetiologies included strictures due to chronic pancreatitis or prior stone passage in 24% of the patients, and malignant obstruction in 16%. In 24% of the patients, no cause was found for biliary dilatation; common duct stones or obstructing tumours were excluded in the group. Since aetiologies other than stones are likely in a majority of cases, further preoperative workup (CT, percutaneous transhepatic cholangiography, ERCP) or intraoperative cholangiography (if the patient requires urgent cholecystectomy) is indicated. The additional studies should provide a diagnosis, help determine whether or not the common duct should be explored, or avoid unnecessary operation in case of incurable malignancy.

Prenatal ultrasonographic diagnosis of congenital adenomatoid malformation of the lung. Correlation with pathology and implications for pregnancy management.

Congenital cystic adenomatoid malformation of the lung is an uncommon malformation. The solid type III variety is the rarest and carries the poorest prognosis. This report describes the prenatal diagnosis of a case of congenital cystic adenomatoid malformation type III at 24 weeks' gestation. The pathologic features of the malformation and the etiology and prognostic significance of hydramnios and anasarca are discussed. This case indicates that the malformation can be diagnosed early enough to allow for therapeutic intervention.

Fetuses aren't small children.

Although great strides in prenatal diagnosis have been made by sonography, interpretation has been complicated by failure to recognize fundamental differences between the uterine and extra-uterine environment. Furthermore, extrapolation of knowledge concerning the same disorders in childhood to fetuses produces misleading information about diagnosis and often, prognosis.