Added Diagnostic Value of Cerebrospinal Fluid Carcinoembryonic Antigen in a Patient with Leptomeningeal Carcinomatosis as the Initial Manifestation of Gastric Cancer

A 77-year-old woman with no history of malignancy presented with anorexia and bilateral lower extremity weakness. Her consciousness level worsened daily, so we performed a lumbar puncture. Cerebrospinal fluid (CSF) analysis indicated meningitis, but three rounds of CSF cytology showed no malignant cells. The patient’s carcinoembryonic antigen (CEA) level was highly elevated in CSF, but normal in serum. Through gadolinium-enhanced brain/spinal magnetic resonance imaging and gastrointestinal endoscopy, she was diagnosed with leptomeningeal carcinomatosis (LC) from gastric cancer. CEA level in CSF facilitated the diagnosis of LC from gastric cancer because there were no malignant cells on CSF cytology

Assessment of MRI Contrast Agent Kinetics via Retro-Orbital Injection in Mice: Comparison with Tail Vein Injection.

It is not known whether administration of contrast agent via retro-orbital injection or the tail vein route affects the efficiency of dynamic contrast-enhanced magnetic resonance imaging (MRI). Therefore, we compared the effects of retro-orbital and tail vein injection on the kinetics of the contrast agent used for MRI in mice. The same group of nine healthy female mice received contrast agent via either route. An extracellular contrast agent was infused via the tail vein and retro-orbital vein, in random order. Dynamic contrast-enhanced MRI was performed before and after administering the contrast agent. The contrast effects in the liver, kidney, lung, and myocardium were assessed. The average total times of venous puncture and mounting of the injection system were about 10 and 4 min for the tail vein and retro-orbital route, respectively. For all organs assessed, the maximum contrast ratio occurred 30 s after administration and the time course of the contrast ratio was similar with either routes. For each organ, the contrast ratios correlated strongly; the contrast ratios were similar. The retro-orbital and tail vein routes afforded similar results in terms of the kinetics of the contrast agent. The retro-orbital route can be used as a simple efficient alternative to tail vein injection for dynamic contrast-enhanced MRI of mice

Typical thoracoabdominal coronal MRI.

<p>Left column, from top to bottom, images acquired before (a), 30 s (b), 3 min 30 s (c), and 10 min (d) after delivery of the contrast agent via the retro-orbital route. Right column, images obtained before (e), 30 s (f), 3 min 30 s (g), and 10 min (h) after delivery of the contrast agent via the tail vein route.</p

Correlation of contrast ratio between tail vein and retro-orbital route.

<p>Panel a, b, c and d shows liver, kidney, lung, and myocardium, respectively.</p