Is age associated with size of adult extrahepatic bile duct: sonographic study.

PURPOSE: To determine if the size of the extrahepatic bile duct increases with age in adults. MATERIALS AND METHODS: A total of 258 consecutive patients 18 years and older, without known biliary or pancreatic disease, who were fasting to undergo routine abdominal sonography were examined. The transverse and anteroposterior dimensions of the extrahepatic bile duct were measured proximally at the porta hepatis, at the middle above the head of the pancreas, and distally at the head of the pancreas. Simple linear regression of the average of these measurements against age tested the hypothesis of a slope of 1.0 mm per decade. RESULTS: The sample included a wide variety of ages: 55 years +/- 16 (mean +/- SD), with a range of 20-92 years, including 151 men and 107 women. One-tenth of the cohort were younger than 35 years old and one-tenth were older than 77 years old. The six measurements were proximal-transverse 3.5 mm +/- 1.0, proximal-anteroposterior 2.9 mm +/- 1.1, middle-transverse 3.9 mm +/- 1.2, middle-anteroposterior 3.4 mm +/- 1.2, distal-transverse 4.1 mm +/- 1.2, distal-anteroposterior 3.5 mm +/- 1.2. Least squares regression slope differed significantly from 0.1 mm per year (95% CI; -0.000703, +0.00110) and in fact contained zero. CONCLUSION: Findings were not able to help confirm an association between age and size of the extrahepatic bile duct in an asymptomatic adult population.

Helical CT scanning: the primary imaging modality for acute flank pain.

We set out to evaluate the accuracy of nonenhanced helical computed tomography (CT) scanning at stone detection in the patient with acute flank pain, and as a means of detecting noncalculus causes of acute flank pain. Between April 1995 and April 1997, 412 consecutive patients with acute flank pain underwent noncontrast-enhanced helical CT. Two hundred eighty-one patients had confirmation of their CT diagnosis by other radiographic studies, urologic intervention, or spontaneous stone passage of calculi. We determined the presence or absence of urinary calculi, as well as the presence of other noncalculus pathology. CT scanning revealed a stone in 92/281 patients (32.7%) and no stone in 189/281 patients (67.3%). Of the 189 patients, 60/189 patients (32%) had another positive finding as a cause for flank pain. Eighty-one of 92 patients with a stone on CT (88%) had confirmation of stone disease by radiologic or surgical intervention. Eleven of 92 patients (12%) did not have confirmation of their diagnosis because of resolution of symptoms or refusal of further intervention. On helical CT scans 129/189 patients demonstrated no abnormalities. Two of 189 (1.5%) thought to be stone free by CT passed a stone. Helical CT had a sensitivity of 97%, a specificity of 92%, a positive predictive value of 88%, and a negative predictive value of 98% at stone detection. Noncontrast-enhanced helical CT is accurate and rapid in detecting calculus disease in patients with acute flank pain. Perhaps more importantly, it provides the added benefit of detecting noncalculus causes of flank pain in greater than 30% of patients.

The limitations of carotid sonography: interpretive and technology-related errors.

OBJECTIVE: This study compared carotid artery sonography with angiography to determine, in retrospect, which types of sonographic errors arose from incorrect interpretation of sonographic images and which errors could be ascribed to the limitations of sonographic imaging. MATERIALS AND METHODS: A review of all patients who underwent carotid artery sonography and angiography between 1993 and 1997 at our institution revealed 66 patients with complete sets of studies, yielding 132 examinations (right or left). Studies were not reinterpreted and angiography was considered to be the gold standard. Only stenoses of 60% or greater were included in our study. If the degree or location of stenosis differed on the two imaging studies, they were reviewed together to classify the type of sonographic error. RESULTS: We found complete agreement of sonography and angiography in 115 cases (87%) and discrepancies in 17 (13%). Thirteen of 17 sonographic errors were false-positive interpretations and three were false-negative interpretations. One was an error in location. Retrospective review showed seven interpretive errors. In all these cases, the color Doppler image better revealed the degree of stenosis. Other complicating factors included inconsistencies between absolute velocities, velocity ratios, and waveforms obtained while a patient was being treated with an intraaortic balloon pump. In the other 10 discrepancies, the sonographic interpretation was accurate. Seven of these cases were false-positive interpretations in patients with contralateral occlusions or stenoses. The other three cases in this group showed long segments of stenosis, ulcerations, or tortuous vessels on angiography. CONCLUSION: Our study suggests that increased accuracy can be achieved in the interpretation of carotid artery sonography by meticulous attention to the color image. When color Doppler sonography is technically limited by tortuosity or ulceration, or if significant contralateral disease is present, misinterpretation is more likely.

Abdominal lymphangioma in a preterm infant.

A newborn infant, noted on prenatal ultrasonography to have a huge, multiseptated cystic intraabdominal mass, had severe respiratory failure at birth because of a massively distended abdomen. Acute treatment included removal of 1.7 L of serous fluid, aggressive respiratory support, and numerous diagnostic studies. Definitive therapy was excision of the cyst by laparoscopy. Pathologic examination showed cystic lymphangioma.

Ultrasonographic features of gastrointestinal duplications.

The variable sonographic appearance of duplication cysts is presented. Eighteen sonograms from 14 patients, aged 1 day to 8 years, were reviewed over an 8 year period. Water and other aqueous contrast agents were used in six patients as part of the sonographic evaluation. All lesions were confirmed by surgery. All but two patients were symptomatic. Twenty-four cysts were detected, ranging in size from 1.7 to 15.5 cm. The duplication cysts revealed a spectrum of sonographic findings (cystic to solid appearing masses). The mass characteristics, including the "muscular rim sign," and internal debris or hemorrhage, were demonstrated. Multiple unsuspected cysts (3 of 14 or 20%) and complications such as perforation were readily seen with ultrasonography. Serial sonograms demonstrated the changing morphology of two cysts. Other unsuspected intra-abdominal and pelvic pathologic conditions, including pyloric stenosis and ovarian cysts, were identified. Identification of the muscular rim sign is the most reliable indication of a duplication cyst. Multiple masses as well as possible accompanying anomalies in the abdomen and pelvis are readily evaluated with sonography. Lesions are easily followed with serial studies if there is no surgical intervention.

The use of ultrasound to determine the position of the mandibular condyle.

A randomized, single blind study of 20 patients examined the accuracy of ultrasound in establishing the position of the mandibular condyle in relation to the glenoid fossa. The sonographic technique is described. The temporomandibular joint was imaged sonographically with the patients in an open- and a closed-mouth position as a model for condylar sag and proper condylar seating, respectively, during mandibular ramus osteotomy procedures. One radiologist identified condylar position correctly in 38 of 40 still ultrasound images, with a sensitivity and a specificity of 95%. During real time ultrasound examination, it is possible to visualize varying degrees of condylar movement in relation to the glenoid fossa. The results of this study support the potential use of ultrasound as an adjunct to mandibular orthognathic surgery.

Enlarged amniotic cavity: a new sonographic sign of early embryonic death.

In the process of evaluating sonograms to determine the status of early gestations, it was noted that enlargement of the amniotic cavity appeared to correlate with embryonic death. This study tested that hypothesis by comparing the size of the amniotic cavity with the crown-rump length (CRL) and the size of the chorionic cavity in 25 normal gestations and 10 cases of embryonic death. Measurements included diameter of the amniotic cavity (Da), diameter of the chorionic cavity (Dc), and CRL. Normal first-trimester embryos have distinct rates of growth for both chorionic and amniotic cavities. Least-squares linear regression of CRL on Da for normal embryos reveals Da = 1.1 x CRL - 0.07 (r = .988, n = 25, p less than 10(-8)), indicating that Da and CRL are almost equal. An abnormal embryo, especially at 5-6 weeks' gestation, will have an abnormally large amniotic cavity for its CRL and the size of its chorionic cavity. The CRL-Da difference of 0.11 +/- 0.20 cm in normal embryos differed significantly from that difference of 0.86 +/- 0.38 cm in abnormal embryos (p less than 10(-8)); however, the chorionic cavity was still appropriate in size for the CRL. These results suggest that an amniotic cavity that is enlarged relative to the CRL and the size of the chorionic cavity is evidence of embryonic death.

Leukemic intestinal pneumatosis.

A benign form of pneumatosis intestinalis has been reported in children with leukemia but also occurs in adults as we report here. Radiologists must be familiar with this entity or a mistaken diagnosis of an abdominal catastrophe will be made, committing the patient to unneccessary emergency surgery.