Child ; Child, Preschool ; Female ; Gastrointestinal Hemorrhage ; diagnosis ; Gastrointestinal Tract ; diagnostic imaging ; Humans ; Infant ; Male ; Radionuclide Imaging ; Sodium Pertechnetate Tc 99m

Computed tomography (CT) is an imaging modality that provides otherwise unobtainable information in the diagnostic workup for acute abdomen. The patient's clinical history, physical examination, and laboratory findings are essential for a correct diagnosis; however, some diagnoses are difficult to establish. Although contrast-enhanced CT is the preferred diagnostic tool and provides invaluable information, using only post-contrast images can lead to misdiagnoses. Unenhanced CT images are more useful than post-contrast images for detecting high-attenuation lesions or materials because surrounding tissues also show high attenuation on post-contrast images. Unenhanced CT often provides key imaging findings for a correct diagnosis; hence, the purpose of this article is to describe CT findings in acute abdomen with high-attenuation lesions in the gastrointestinal tract.
Adult ; Humans ; Abdomen, Acute/diagnostic imaging* ; Contrast Media ; Tomography, X-Ray Computed/methods* ; Gastrointestinal Tract/diagnostic imaging* ; Retrospective Studies

Wireless capsule endoscopy is currently the outstanding technical innovation in diagnostic gastrointestinal endoscopy. Especially for small bowel diseases this new technique offers several potential advantages over traditional diagnostic tools. The Given Diagnostic Imaging System (Given Imaging Ltd, Norcross, GA) consists of 3 components : the M2A capsule, an external receiving antenna with an attached portable hard drive, and a personal computer workstation for review and interpretation of images. The M2A capsule is a single-use device measuring 11x 26 mm and weighing 3.7 g. It is made of a biocompatible plastic and contains a complimentary metal oxide silicon chip camera, lens, light source, battery, and radio telemetry transmitter. Images are transmitted at 2 per second to an antenna array worn on the abdomen and stored on a Walkman-sized data recorder. The Given system was approved by the Food and Drug Administration in August 2001. The method has chiefly been used in patients with obscure gastrointestinal bleeding, and in some cases has allowed additional diagnoses to be made in comparison with push enteroscopy, with a positive influence on patient management. Contraindications to performance of capsule endoscopy include known or suspected GI obstruction, strictures or fistula, and presence of a cardiac pacemaker, defibrillator, or other implanted electromedical device. The M2A capsule is probably just the first in a long line of wireless endoscopic devices. There are already prototypes of self-propelled devices. Soon to come will real-time imaging, devices to image the proximal GI tract and colon, and devices that can take biopsies or provide therapy.
Abdomen ; Biopsy ; Capsule Endoscopes* ; Capsule Endoscopy ; Colon ; Constriction, Pathologic ; Defibrillators ; Diagnosis ; Diagnostic Imaging ; Endoscopy, Gastrointestinal ; Fistula ; Gastrointestinal Tract ; Hemorrhage ; Humans ; Microcomputers ; Plastics ; Telemetry ; United States Food and Drug Administration

A 16-year-old Chinese male patient presented with constipation lasting five days, colicky abdominal pain, lethargy, weakness and body aches. He was able to pass flatus. Abdominal radiography showed a distended stomach causing inferior displacement of the transverse colon. Computed tomography revealed a dilated oesophagus, stomach and duodenum up to its third portion, with a short aortomesenteric distance and narrow angle. There was also consolidation in the lungs bilaterally. Based on the constellation of clinical and imaging findings, a diagnosis of superior mesenteric artery syndrome complicated by aspiration pneumonia was made. The patient was subsequently started on intravenous hydration, nasogastric tube aspiration and antibiotics. Following stabilisation of his acute condition, a nasojejunal feeding tube was inserted and a feeding plan was implemented to promote weight gain. The clinical presentation, differentials, diagnosis and treatment of superior mesenteric artery syndrome are discussed.
Adolescent ; Aged ; Child ; China ; Duodenum ; diagnostic imaging ; Enteral Nutrition ; Fluoroscopy ; Gastrointestinal Tract ; diagnostic imaging ; Humans ; Male ; Mesenteric Arteries ; diagnostic imaging ; physiopathology ; Pneumonia, Aspiration ; diagnostic imaging ; Radiography, Abdominal ; Superior Mesenteric Artery Syndrome ; diagnostic imaging ; Syndrome ; Tomography, X-Ray Computed ; Vomiting ; diagnostic imaging

OBJECTIVE: Suspicious incidental gastrointestinal FDG uptake during positron-emission tomography/computed tomography (PET/CT) examinations can be caused by different diseases, including malignancies. However, differentiation with PET alone is difficult. The aim of this study was to investigate the potential of PET alone, contrast-enhanced CT (ceCT), and low-dose CT (ldCT) in routine PET/CT protocols for differentiation of incidental gastrointestinal lesions. MATERIALS AND METHODS: Sixty patients with incidental gastrointestinal lesions who underwent a routine PET/CT protocol with ldCT and ceCT were retrospectively analysed. The PET lesions were evaluated regarding their FDG uptake patterns and the standard uptake value. The anatomical correlates in both CT protocols were compared in regard to the correct lesion classification with the reference standard endoscopy. RESULTS: Sixty-two lesions were found in 60 patients (17 malignant, 10 premalignant, 5 benign, 13 inflammatory, 17 physiological). The differentiation of the FDG uptake patterns did not enable reliable lesion classification. The positive predictive value for pathology was 0.81 for ceCT in PET/CT and 0.70 for ldCT. Malignancies were detected in 100% of the patients by ceCT vs. 29.4% by ldCT. The false negative rate of ceCT for all pathologies was 31.1%, vs. 68.9% for ldCT. False positive results (17/62) could not be excluded sufficiently by either CT protocol. CONCLUSION: PET/ceCT protocols provide additional benefit especially in detecting gastrointestinal malignancies as a cause of suspicious incidental gastrointestinal FDG uptake. However, since follow-up endoscopy cannot be forgone due to the considerable false negative rate even with ceCT, the addition of ceCT to a routine PET/ldCT protocol cannot be recommended for this purpose.
Adult ; Aged ; Aged, 80 and over ; Contrast Media/diagnostic use/pharmacokinetics ; Female ; Fluorodeoxyglucose F18/*diagnostic use/pharmacokinetics ; Follow-Up Studies ; Gastrointestinal Diseases/*diagnosis/metabolism ; Gastrointestinal Tract/*metabolism/radiography/radionuclide imaging ; Humans ; Male ; Middle Aged ; Positron-Emission Tomography/*methods ; Reproducibility of Results ; Retrospective Studies ; Tomography, X-Ray Computed/*methods

OBJECTIVETo investigate the value of 11C-PD153035 as an EGFR imaging agent in C6 tumor-bearing rat.

METHODSThe tumor-bearing rats were generated by subcutaneous injection of glioma C6 cells. Positron emission tomography/computer tomography (PET/CT) scans started as soon as intravenous injection of 11C-PD153035 (15-20 MBq/0.3 ml) was completed, images were collected continuously. The region of interest (ROI) was used to study the percentage of radioactivity in major organs and implanted tumors in the rats. The accumulation and blocking study in vitro was completed.

RESULTSThere were significant differences in 11C-PD153035 uptake among major organs. The maximum uptake in the organs ranked in the following order: liver > gastrointestinal tract > kidney > lung > brain > muscle. Radioactivity could be also observed in the tumors. The radioactivity ratio (T/NT, target/non-target) peaked (4.15) at 40 - 50 min post injection. The in vitro blocking study showed that 11C-PD153035 uptaken by C6 cells could be blocked by PD153035.

CONCLUSIONThe results of this study show that 11C-PD153035 can be uptaken by EGFR-expressing tumors. 11C-PD153035 has a potential as a bioprobe to yield useful information for both diagnosis and therapy of tumors. However, the high concentration of 11C-PD153035 in the gastrointestinal tract is unfavorably affecting the tumor detection in these organs.

Animals ; Brain Neoplasms ; diagnostic imaging ; metabolism ; pathology ; Carbon Radioisotopes ; Cell Line, Tumor ; Gastrointestinal Tract ; metabolism ; Glioma ; diagnostic imaging ; metabolism ; pathology ; Liver ; metabolism ; Male ; Neoplasm Transplantation ; Positron-Emission Tomography ; Quinazolines ; pharmacokinetics ; Rats ; Rats, Wistar ; Receptor, Epidermal Growth Factor ; metabolism ; Tissue Distribution ; Tomography, X-Ray Computed