RESUMEN

We investigated a patient with extramedullary plasmacytoma in the retroperitoneal space with multiple metastases using abdominal CT scan and 67Ga scintigraphy. Abdominal enhanced CT revealed the retroperitoneal tumor mimicking lymphoma. 67Ga scintigraphy showed multiple tumor localization. We could detect retroperitoneal extramedullary plasmacytoma with multiple metastases using 67Ga scintigraphy. This retroperitoneal tumor may appear similar to lymphoma on CT.

Asunto(s)

RESUMEN

We studied 35 patients with lacunar infarcts, using diffusion-weighted echo-planar imaging (DW-EPI) at 1.5 T. The relative apparent diffusion coefficient ratio (ADCR) of each lesion was calculated and lesion conspicuity on DW-EPI was compared to that on images acquired with fast fluid-attenuated inversion recovery and T2-weighted fast spin-echo sequences. Acute small infarcts (within 3 days) were identified with DW-EPI as an area of decreased ADCR (range 0.33-0.87; mean 0.67) and high signal, subacute small infarcts (4-30 days) as a high-signal or isointense areas of decreased or nearly normal ADCR (0.54-0.98; 0.73), and chronic small infarcts (> 30 days) as low- or high-signal areas of nearly normal or increased ADCR (0.97-1.92; 1.32). In three patients, small infarcts of the brain stem in the hyperacute phase (within 6 h) were seen only with DW-EPI. In five patients, fresh small infarcts adjacent to multiple old infarcts could be distinguished only with DW-EPI.

Asunto(s)

Asunto(s)

RESUMEN

SPECT imaging with I-123 IMP or Tc-99m HMPAO was performed in two patients with Creutzfeldt-Jakob disease to evaluate abnormalities in brain perfusion. In the first patient, there was decreased perfusion of the left frontal, parietal, and temporal lobes. CT and MRI were negative. In the second patient, there was patchy perfusion and slightly decreased perfusion of the right hemisphere. MRI revealed slight brain atrophy and bilateral high intensity areas in the basal ganglia on T2 weighted images. Subsequent SPECT imaging revealed severely decreased perfusion of the entire brain. Subsequent MRI demonstrated severe brain atrophy.

Asunto(s)

RESUMEN

We carried out a study to evaluate treatment response and residual mass in irradiated lung cancer with single photon emission computed tomography (SPECT) using 201TI, and investigated the relation among 201TI uptake ratio, tumor volume, and patient survival time. 201TI uptake ratios and tumor volume measured before and after radiotherapy were compared in 14 patients. We divided them into a complete response (CR) group (n = 5) and partial response + no change (PR + NC) group (n = 9) according to the tumor volume response determined by CT, and a longer survival (LS) group (n = 7) and shorter survival (SS) group (n = 7) according to the survival time. The CR group showed smaller 201TI uptake ratios after irradiation (5.3 +/- 6.0%) than the PR + NC group (52.0 +/- 27.4%) (p < 0.01), but there were no significant differences in 201TI uptake ratio before irradiation or survival time in the other two groups. The LS group showed a smaller 201TI uptake ratio before (107.8 +/- 48.3%) and after (17.0 +/- 14.4%) irradiation than the SS group (126.6 +/- 34.4% p < 0.01, 52.6 +/- 27.5% p < 0.05), but there were no significant differences in tumor volume before or after irradiation in the other two groups. We concluded that 201TI SPECT is very useful to evaluate treatment response in irradiated lung cancer and can play a supplementary role in evaluating prognosis.

Asunto(s)

Asunto(s)

RESUMEN

OBJECTIVE: The purpose of our study was to characterize the relationship between signal intensity on STIR MRI, histology, and liver function. MATERIALS AND METHODS: MRI was performed in 39 patients with chronic liver diseases [chronic persistent hepatitis (CPH), chronic active hepatitis (CAH), liver cirrhosis (LC)] and 11 patients without liver dysfunction (normal). RESULTS: On STIR images, very low signal intensities compared with those of the spleen were seen in all 11 normal livers (100%), and brighter intensities were seen in chronic diffuse liver diseases (10 patients with CPH, 11 patients with CAH, and 18 patients with LC) (100%). The higher the signal grade on STIR images (moderate, marked), the more advanced was the chronic diffuse liver disease (p < 0.02). The levels of serum glutamic-oxaloacetic and glutamic-pyruvic transaminase increased in parallel with increasing signal intensity on STIR images (both p < 0.01). CONCLUSION: We found that the signal intensity of liver on STIR images appeared to be associated with the degree of histologic and/or clinical severity in patients with chronic liver disease.

Asunto(s)

RESUMEN

Wandering spleen is the term commonly applied to splenic hypermobility that results from laxity or maldevelopment of its suspensory ligaments. It comes to medical attention usually as an abdominal mass, or when the spleen undergoes torsion. Diagnosis on clinical grounds alone is rarely made, and ultrasonography, CT and MRI findings have no specific characteristics for this condition. 99mTc-labeled colloid taken up by the spleen may provide a specific diagnosis. We report a case of wandering spleen, in which the preoperative diagnosis was made on the basis of sequential liver-spleen scintigraphy with 99mTc-Sn-colloid and blood-pool scintigraphy with 99mTc-RBC. This is a rare case, in which hypermobility was assessed by sequential 99mTc-Sn-colloid scintigraphy, and to our knowledge, is the first case in which 99mTc-RBC scintigraphy provided useful information on splenic blood volume and its location.

Asunto(s)

RESUMEN

In order to evaluate 201Tl SPECT for the assessment of tumor viability after radiation therapy. Twenty rabbits were implanted with VX-2 tumor in the left femoral muscles and were classified into four groups as follows: normal control group (N), 20 Gy irradiated response group (A), 20 Gy irradiated non-response group (B), and 40 Gy irradiated group (C). Eight days after implantation, 201Tl SPECT and CT studies were performed to assess the changes in 201Tl uptake and tumor volume at 0, 1, 2, 3, and 4 weeks after single irradiation. Histologic specimens were also taken. In group N tumors continued to increase in volume, but 201Tl uptake showed a steady decrease after 2 weeks. In group A tumors continued to increase in volume, but 201Tl uptake showed a transient decrease at 2 weeks, then a steady increase. In group B tumors showed a transient increase in volume at 2 weeks, then a continuous decrease, but 201Tl uptake showed a continuous decrease throughout the study. In group C there was a continuous decrease both in volume and 201Tl uptake with the later more prominent. 201Tl uptake was decreased earlier than tumor volume both in group B and C, at one week that was significant (p < 0.01). 201Tl uptake by tumor reflects the burden of viable tumor on histology; therefore 201Tl SPECT is of great use in assessing the therapeutic effects on tumors.

Asunto(s)

Asunto(s)

RESUMEN

We report two cases of left ventricular diverticulum assessed by magnetic resonance (MR) and radionuclide imaging. MR imaging clearly demonstrated the diverticulum in each case, where abnormal perfusion was observed on Tl-201 myocardial SPECT.

Asunto(s)