Search

Visualization of cerebral perfusion with Single Photon Emission Computed Tomography (SPET) needs lipophil radiotracers which are able to cross the intact blood-brain-barrier (BBB); moreover local uptake must reflect regional cerebral blood flow. In the last decade many radiopharmaceuticals have been suggested and employed for this purpose. Recently a new molecule has been synthesized: technetium-99m-labeled ethyl cysteinate dimer (99mTc-ECD). Commonly, SPET of the brain with perfusion tracers is performed to identify ischemic regions. We describe a patient with a bulky cerebral metastasis, secondary to Hurthle cell carcinoma of the thyroid, which concentrated radioiodine. Brain metastases secondary to differentiated carcinoma of the thyroid are very rare and when treated with 131-I may provoke serious neurological problems. Therefore we decided to perform a brain SPET with 99mTc-ECD to exclude regional perfusion defects and deafferentation phenomena. Brain CT showed only the large metastasis. SPET images, reconstructed according to standard tomographic planes of the head: transverse, coronal and sagittal revealed no uptake of 99mTc-ECD within the metastasis and no regional perfusion defects related to compression phenomena or deafferentation. 99mTc-ECD has never been used to image cerebral neoplasm of whatever origin.

Carcinoids, tumors arising from enterochromaffin cells, represent the most common type of gastrointestinal endocrine neoplasm; they are often multiple and may appear anywhere in the gut. Carcinoid tumors may also occur in bronchi and ovaries. Classic symptomatology includes secretory diarrhea, flushing, edema, bronchospasm and cutaneous teleangectasias; however, over 30% of patients with demonstrably elevated serotonin levels may not exhibit any symptoms at all. The diagnosis of carcinoid tumor is typically made by measurement of 24-hour urinary excretion of 5-hydroxyindoloacetic acid. Commonly, tumor localisation is established with CT, US, NMR and arteriography. MIBG scintigraphy is also used to visualize tumors deriving from neuroendocrine cells as carcinoid. These tumors may express somatostatin receptors located on the cell surface. Therefore 111In Octreotide (Octreoscan), a somatostatin analogue, can be employed for tumor localisation. A 32-years-old man with liver metastases secondary to a carcinoid tumor of unknown origin is presented. Classic carcinoid symptoms were absent. Diagnosis was supported by elevated values of urinary 5-hydroxyindolocetic acid and liver fine-needle aspiration. Abdominal US and CT scan detected only liver masses but not the primary tumor. Arteriography was not performed. 131I MIBG and 111I octreotide scans both failed in locating the primary cancer too; only the second tracer showed marked uptake in liver metastases. Beside localization, these two tracers give also informations about the following therapy especially in malignant tumors where local resection isn't an adequate treatment.

Twelve patients affected by idiopathic osteonecrosis of the femoral head underwent X-ray, triphasic bone scintigraphic (TBS) and CT tests on the femoral head on both sides. TBS revealed arterial hypoperfusion and an area of hypocaptation in the caput femoris in 3 coxofemoral joints which were radiologically "negative" (and of which one was also CT negative); these are scintigraphical signs which are typical of aseptic necrosis. In line with published data, TBS was found to be a more sensitive test in comparison with traditional X-ray techniques and CT, and in the early stages of disease it is more specific in recognising aseptic necrosis of the femoral head. Lastly, it is underlined that magnetic resonance is currently considered to be most sensitive (88%) and most specific (100%) imaging technique in the diagnosis of osteonecrosis of the femoral head.

Intestinal transit patterns were studied in 20 normal volunteers. It was found that small changes in transit time occurred in the passage from the caecum to the sigmoid and rectum, and that most subjects evacuated the capsule 38 hr after its ingestion.

Intestinal transit time was studied in two groups of 8 patients with irritable colon. In the first group, the time was longer than normal, whereas in the second it was accelerated. Three subjects in each group received a placebo, while the other five received 60 mg/day bromopride for 15 days. No change in transit time was noted in the controls. Two subjects in Group I displayed a significant reduction in transit time after bromopride, while deceleration and normalisation were observed in 4/5 patients in Group II.

Esophago-jejunal reconstruction, after total gastrectomy, is best performed by one of the following three operations: interposed jejunal loop, Roux-en-Y loop and "omega" loop with Braun anastomosis. To assess the effects of the three mentioned techniques three groups of 15 patients each were examined after total gastrectomy for I, II or III stage cancer. Four to ten months after surgery all patients underwent the following tests: a) esophago-jejunal transit with labeled solid meal; b) cholangio-scintigraphy and c) absorption test of biliary acids. A group of 10 patients, without gastrointestinal pathology, was selected for comparison. The data obtained from the comparative study, in agreement with the opinions held by many Authors and our previous research, demonstrate that the interposition of jejunal loop (Mouchet) is the reconstructive technique closest to the unoperated stomach and, for this reason, is to be preferred after total gastrectomy.