Wandering humeral head mimicking a breast mass.

A 74-year-old woman was incidentally found to have a left breast mass. The mass could not be adequately compressed to be visualized on mammography. Ultrasonography showed a heavily-calcified rounded mass in the left axillary tail of the left breast. Chest radiograph confirmed that the mass was a migrated humeral head. Remotely-displaced fracture-dislocations of the humeral head are very rare and to our knowledge, displacement into the breast, clinically mimicking a breast mass, has not been previously described.

Adult intussusception: experience in Singapore.

INTRODUCTION: Gastrointestinal intussusception is an uncommon clinical entity in adults and is interestingly distinct from its paediatric form. In adults an identifiable lead lesion is found in the majority of cases, of which a significant percentage are malignant. Its treatment is thus different from that of paediatric intussusception. The present study reviews our experience of treating adult intussusception. METHODS: A retrospective review of patients with a postoperative diagnosis of gastrointestinal intussusception between January 1997 and December 2002 was conducted. All patients under the age of 18 and cases of rectal prolapse were excluded. RESULTS: During the 5-year period, there were nine cases of intussusception. There were four male and five female patients, with a mean age of 63.8 years (range 37-85 years). Less than half of the patients (44.4%) presented with acute symptoms. The most common symptoms were abdominal pain and distension. The symptoms were intermittent in 77.8% (7 of 9) of patients. Only two patients had a palpable abdominal mass, while another had signs of acute intestinal obstruction. Computed tomography was the most useful imaging modality, identifying intussusception in six out of six patients. Eight patients had lead lesions occurring at the ileocaecal junction resulting in ileo-colonic intussusception. Of these eight, four were malignant (two adenocarcinomas and two lymphomas). There was one sigmoid-rectal intussusception secondary to adenocarcinoma. All patients were treated operatively. Seven patients were treated with en bloc resection. CONCLUSION: Although uncommon, surgeons need to be aware of the epidemiology and treatment options for adult intussusception. The symptoms and signs are often non-specific and the surgeon might be faced with the diagnosis only at laparotomy. Computed tomography is the most useful imaging modality. An identifiable organic lesion is present in most cases, of which more than 50% are malignant (especially in the large bowel). Operative treatment is thus prudent. En bloc resection is recommended for ileo-colonic and colo-colonic intussusception. There is, however, a role of initial reduction in selected patients with ileo-ileal intussusception.

Celiac artery compression by the median arcuate ligament: a pitfall of end-expiratory MR imaging.

PURPOSE: To measure the prevalence and degree of celiac artery compression during breath-hold imaging at end inspiration and end expiration in patients referred to undergo magnetic resonance (MR) imaging of the abdomen for reasons unrelated to intestinal ischemia. MATERIALS AND METHODS: A series of 100 patients underwent routine MR imaging of the upper abdomen at 1.5 T; imaging included multiple dynamic contrast-enhanced fat-suppressed transverse three-dimensional spoiled gradient-echo acquisitions (3.6-4.5/1.5-1.9 [repetition time msec/echo time msec], 12 degrees flip angle). Arterial phase acquisitions were obtained during suspended respiration at end expiration (n = 50) or at end inspiration (n = 50), and venous phase acquisitions were obtained at the opposite respiratory phase. Two radiologists, blinded to patient identity and the phase of respiration, independently assessed the degree of narrowing on reconstructed oblique sagittal images. Radiologists reached consensus in 97 patients, who formed the cohort for this study. The percentage of stenosis of the celiac artery relative to its origin and the angle formed by the proximal celiac artery and the aorta were also measured in all patients. This angle and the arcsine transformation of the percentage of stenosis were compared for the two respiratory phases by using a paired Student t test. chi2 analysis was used to evaluate whether the degree of narrowing was independent of the breath-hold protocol that was used. RESULTS: In total, 55 (57%) of 97 patients had at least mild artery narrowing at end expiration, of whom 40 (73%) had less narrowing at end inspiration and 11 (20%) had no change. The average percentage of stenosis at end expiration (21% +/- 16) was significantly higher than that at end inspiration (11% +/- 11; P <.001). At end expiration, the average celiac artery angle was significantly lower in patients with mild to severe narrowing (41 degrees +/- 19) than in those without narrowing (50 degrees +/- 19; P <.03). CONCLUSION: Accentuation of celiac artery compression at end expiration can give rise to a potential pitfall of breath-hold abdominal imaging. When compression is suspected, imaging should be performed during inspiration.

Three-dimensional, T1-weighted gradient-echo imaging of the brain with a volumetric interpolated examination.

BACKGROUND AND PURPOSE: T1-weighted, 3D gradient-echo MR sequences can be optimized for rapid acquisition and improved resolution through asymmetric k-space sampling and interpolation. We compared a volumetric interpolated brain examination (VIBE) sequence with a magnetization-prepared rapid acquisition gradient echo (MP RAGE) sequence and a 2D T1-weighted spin-echo (SE) sequence. METHODS: Thirty consecutive patients known or suspected to have focal brain lesions underwent postcontrast studies (20 mL of gadopentetate dimeglumine) with VIBE, MP RAGE, and 2D T1-weighted SE imaging. Source and 5-mm VIBE and MP RAGE reformations, and 5-mm T1-weighted SE images were compared qualitatively and by using signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR). SNRs in a gadolinium-doped water phantom were also measured for all three sequences. RESULTS: On the source images, SNRs for gray matter (GM) and white matter (WM), and CNRs for WM-to-GM and contrast-enhancing lesion-to-GM were slightly, but significantly higher for the VIBE sequence than for the MP RAGE sequence (P <.05). On 5-mm reformations, WM-to-GM CNR was significantly higher on VIBE and MP RAGE images than on T1-weighted SE images (P <.001), but contrast-enhancing lesion-to-GM CNRs were higher on SE images compared with both gradient-echo sequences (P <.001). Qualitatively, VIBE images showed fewer flow artifacts than did SE and MP RAGE images (P <.05). In the phantom, VIBE SNR was higher than MP RAGE SNR for short T1 relaxation times. CONCLUSION: VIBE provides an effective, alternative approach to MP RAGE for fast 3D T1-weighted imaging of the brain.