Thoracolumbar compression fractures presenting with an acute ileus.

Corticosteroids are commonly used in the treatment of connective tissue diseases such as systemic lupus erythematosus. Although they are usually efficacious, osteoporosis leading to spine compression fractures is not uncommon. In this case report, we describe an elderly patient with systemic lupus erythematosus on long-term corticosteroid therapy who presented with symptoms of acute abdomen with minimal low back symptoms. No intraabdominal process was found by abdominal studies and exploratory laparotomy. Increased lower back symptoms led to further skeletal spine studies, which initially demonstrated a compression fracture at the twelfth thoracic (T12) vertebra. Later, a T8 and a fourth lumbar (L4) compression fracture were also found. Her abdominal and lower back symptoms resolved on conservative therapy. Although the rate of these occurrences are unknown, compression spine fractures should be considered in elderly patients presenting with acute abdomen after being on long-term corticosteroid therapy.

Cardiovascular disease: evaluation with MR phase imaging.

Magnetic resonance phase images are derived from conventional spin-echo (SE) pulse sequences and display properties of proton movement that occurs with blood flow. SE magnitude and phase images were obtained and retrospectively evaluated in 21 patients referred for potential cardiovascular abnormalities in which intracardiac or intravascular signal was detected. Abnormalities included intravascular and intracardiac thrombus, aneurysm, aortic dissection, flow alteration, atherosclerotic disease, and congenital cardiac anomaly. Thrombosis (six cases) was successfully differentiated from flow-related signal (15 cases) by comparing phase images with SE magnitude images; in cases of thrombosis, there was no phase shift in corresponding areas of increased signal intensity. In comparison, SE magnitude signal intensities alone were not an accurate indicator in differentiating thrombus from flow-related enhancement. Because phase images are sensitive for identifying flow, the SE magnitude signal of intravascular tumor or thrombus can be differentiated from that of flow effects with more clinical confidence.

Pitfalls in the CT diagnosis of atlantoaxial rotary subluxation.

CT was used to examine six patients with clinically evident atlantoaxial rotary fixation, two patients with torticollis, and six normal subjects who had turned their heads to the side as far as voluntarily possible. The CT appearances of the atlantoaxial complex were identical in all three groups. To differentiate these groups, we propose a functional scan through C1-C2 in which patients are scanned initially as they present, with their heads fixed in lateral rotation. Subsequent scans are obtained with their heads turned to the maximum contralateral rotation. CT scans in patients with atlantoaxial rotary fixation demonstrate no motion at C1-C2 during this maneuver, while those in patients with transient torticollis show a reduction or reversal of the rotation of C1 on C2.

Heterogeneity of tumor cells from a single mouse mammary tumor.

By the use of a variety of cell culture and separation methods, four cell lines were isolated from a single autochthonous BALB/cfC3H mammary tumor. These lines differ markedly from each other in culture morphology, various in vitro growth properties, expression of murine mammary tumor virus antigen, and karyotype, yet all four lines are tumorigenic in normal, syngeneic hosts, yielding tumors of generally similar histology, although distinct from the original neoplasm. Three of the four lines have been cloned from soft agar. The clones exhibit the same growth properties as the lines from which they were derived. Karyotypic analysis of the parent tumor revealed the presence of cells with heterogeneous numbers of chromosomes similar to those seen in the isolated lines, suggesting both the presence of these distinct cell types in the original neoplasm and a genetic origin of the diversity.