Emergency department screening for ectopic pregnancy: a prospective US study.

PURPOSE: To determine the effectiveness of pelvic sonography as a screening test for ectopic pregnancy. MATERIALS AND METHODS: Pelvic sonograms were prospectively analyzed in 1,427 consecutive patients with a serum level of the beta subunit of human chorionic gonadotropin of over 1,500 IU/L. RESULTS: Sonograms were diagnostic in 1,158 patients and indeterminate in 269. When indeterminate studies were considered falsely negative, the diagnostic accuracy was 81%. Twenty-four percent of patients with indeterminate studies were subsequently proved to have ectopic pregnancy. In ectopic pregnancy (n = 103), the most common finding was a complex adnexal mass (specificity = 92% [P < .001]). The sensitivity and specificity of screening sonography for ectopic pregnancy were 99% and 84%, respectively. CONCLUSION: Pelvic sonography is an effective screening test for ectopic pregnancy. Having a one in four chance of harboring an ectopic pregnancy, patients with indeterminate studies require close follow-up. The presence of a complex adnexal mass is a strong predictor of ectopic pregnancy.

Computed tomographic evaluation of benign and inflammatory disorders of the female pelvis.

The use and importance of CT in the evaluation of patients who have inflammatory conditions of the pelvis has increased in recent years. Although its role may be limited in women of childbearing age, CT may provide definitive diagnostic information concerning benign pelvic masses frequently present in this age group. CT is particularly valuable in detecting infectious complications in the postpartum and postoperative pelvis. In patients who have known or suspected inflammatory conditions of the bowel, CT is the imaging modality of choice to identify extraluminal complications such as abscess formation. CT is frequently diagnostic in cases of diverticulitis and appendicitis and is of recognized value in guiding percutaneous drainage procedures, often sparing emergent surgical intervention.

Magnetization transfer of hepatic lesions: evaluation of a novel contrast technique in the abdomen.

The authors evaluated the technique of magnetization transfer to determine if it could enable distinction of benign from malignant liver lesions. Thirteen patients with 27 hemangiomas or cysts and 13 patients with 31 malignant liver lesions underwent magnetic resonance imaging. Hepatic malignancies demonstrated magnetization transfer similar to that of the liver. However, hemangiomas and cysts showed significantly less magnetization transfer than malignant liver lesions. Gradient-recalled-echo imaging with the off-resonance saturation pulse showed increased lesion contrast compared with the liver for hemangiomas and cysts but not for malignancies. On the basis of signal intensity measurements alone (ie, ignoring morphologic criteria), the magnetization transfer studies showed an area under the receiver operating characteristic curve of 0.96 for distinguishing benign from malignant liver lesions. Though the separation of these two groups was imperfect, it was comparable with that achieved with qualitative analysis of signal intensity ratios at spin-echo imaging.

Differential diagnosis of hepatic neoplasms: spin echo versus gadolinium-diethylenetriaminepentaacetate-enhanced gradient echo imaging.

Early results are reported of hepatic neoplasms studied with dynamic gadolinium-diethylenetriaminepentaacetate (Gd-DTPA)-enhanced magnetic resonance imaging (MRI). The purpose of this study was to evaluate the potential of the Gd enhancement pattern for characterizing these neoplasms and to compare the performance of spin-echo (SE) to SE plus dynamic Gd-enhanced gradient-echo (GRE) pulse sequences. Forty-two patients with hepatic neoplasms were examined at 1.5 T field strength. In each patient, short and long repetition time/echo time (TR/TE) SE images were obtained, followed by pre- and post-Gd-DTPA (0.1 mmol/kg body wt), single-slice, breath-hold (13 s/scan) GRE images, which were serially acquired less than or equal to 12 min postinjection. The patterns of contrast enhancement of the various hepatic lesions were documented and analyzed. The time to peak Gd signal enhancement-to-noise ratio (SE/N), contrast-to-noise ratio (C/N), contrast (defined as the signal intensity ratio [SIR]), as well as the peak values of these quantities, were determined. The C/N and SIR values on the short and long TR/TE SE and pre-Gd GRE images for all hepatic neoplasms were also obtained. The discriminating abilities (hemangiomas vs. malignant neoplasms) of these quantities were analyzed statistically. In addition, the impact of lesion characterization on the SE versus the SE plus the Gd-enhanced GRE scans was assessed by means of a blinded reader study. Malignant hepatic neoplasms could be differentiated from hemangiomas by visual inspection of their enhancement patterns (p = 0.0009), by the time to peak C/N on Gd-enhanced images (p = 0.0002), and by the magnitude of such peak (p = 0.02). Combined SE + Gd-enhanced GRE scans afforded minor, though statistically significant (p less than 0.01), improvement of the accuracy in differentiating benign from malignant hepatic neoplasms. Late scans (12 min post-Gd) may be particularly useful in identifying hemangiomas that, unlike other neoplasms, have a significant high signal of their enhancing portions on such images.

Pulmonary arteriovenous malformations: diagnosis by gradient-refocused MR imaging.

Six known or suspected pulmonary arteriovenous malformations (AVMs) in four patients were evaluated with magnetic resonance (MR) imaging at 1.5 T. All lesions were imaged using a gradient-refocused echo pulse sequence with a 25/13 ms [repetition (TR)/echo (TE) times] and a 30 degrees flip angle, as well as with a cardiac-gated spin echo short TR/TE pulse sequence technique. Five of the lesions were vascular in nature based on their signal intensity characteristics, and one nonvascular lesion was a carcinoid tumor. On the spin echo images, the AVMs showed a central signal intensity void with a peripheral rim of intermediate signal intensity that was detectable for lesions greater than or equal to 1.5 cm in size. Smaller lesions were more difficult to distinguish from the surrounding air-filled lung, which normally generates no appreciable signal on MR images. The AVMs demonstrated uniform high signal intensity on the gradient echo pulse sequence and were more conspicuous, irrespective of size. With a single breath-hold scan, the vascular nature of the lesion could be rapidly confirmed with an acquisition time of 13 s. In three patients, the cine MR gradient echo images showed a pulsatile quality to the signal intensity in the lesion over the cardiac cycle similar to that within adjacent pulmonary vessels. The results of this study show a potential role for gradient echo MR imaging as a rapid, noninvasive method to evaluate the vascular nature of an atypical pulmonary nodule.

Disorders of the fetal thorax and abdomen.

Many disorders of the fetal thorax and abdomen can be evaluated using ultrasound. Even when a definitive diagnosis cannot be made prenatally, sonography can provide valuable clinical information regarding the nature and location of the abnormality, associated anomalies, and the presence of secondary complications. An awareness of these disorders and their sonographic appearance is important to impact upon obstetrical management and overall prognosis.

Pulmonary vascular cine MR imaging: a noninvasive approach to dynamic imaging of the pulmonary circulation.

Cine gradient-recalled magnetic resonance (MR) imaging, which has flow sensitivity and high temporal resolution, may potentially yield both morphologic and dynamic flow-related information in the pulmonary vasculature. The authors used this modality to evaluate pulmonary vessels in 12 healthy subjects and in 14 patients with a variety of cardiopulmonary disorders. Normal pulmonary arteries and veins were characterized by distinctive signal intensity and diameter variations as well as motion of the vessels during the cardiac cycle. Patients with pulmonary arterial hypertension demonstrated loss of the normal pulsatile systolic increase and diastolic decline in velocity-related signal intensity and in diameter of the proximal pulmonary arteries. Disorders of pulmonary venous signal and diameter profiles during the cardiac cycle, which show a characteristic biphasic pattern in healthy subjects, were identified in five patients with mitral valvular disease. These initial results indicate that cine MR imaging techniques hold promise in the evaluation of pathophysiologic conditions in the pulmonary circulation.

Calcified transitional cell carcinoma of the renal pelvis.

Six patients with calcified transitional cell carcinoma of the renal pelvis were encountered over a 10-year period, and the radiographic features in these cases are presented. Radiographically discernible calcification is one of the less common manifestations of this lesion, and the pattern of calcification may be variable. However, the combination of a coarse, punctate pattern with a mucosal lesion on excretory or retrograde urography should suggest the diagnosis and prompt further investigation.