摘要:

Vasoactive intestinal peptide–secreting tumors (VIPomas) are extremely rare and difficult to diagnose. The authors describe a patient who was found to have a VIPoma after 3 years of symptoms. Somatostatin receptor scintigraphy using indium-labeled octreotide localized her tumor and prompted a surgical resection. This is the preferred imaging study for the earliest, most accurate, and cost-effective identification of VIPomas and their metastases.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

PurposeThe authors’ goal was to determine whether the prevalence of pulmonary embolism in patients with matching ventilation–perfusion (V–Q) defects and chest radiographic opacities differs depending on the degree of perfusion deficit (absent versus decreased).MethodsThe authors performed a retrospective analysis of the data obtained from the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study. In 233 patients, angiograms were of diagnostic quality for 275 lung zones that showed matching V–Q defects and chest radiographic opacities (triple matches). Of these, V–Q scans and chest radiographs from 217 patients with triple matches in 255 lung zones were retrieved and reviewed. Areas corresponding to chest radiographic opacities were scored as having either decreased perfusion or absent perfusion by consensus. Information regarding the presence or absence of pulmonary embolism in corresponding lung zones was obtained from the PIOPED database.ResultsThe overall prevalence of pulmonary embolism in all lung zones with triple matches was 27% (69 of 255). Of the 255 areas of triple matches, the perfusion was decreased in 153 (60%) and absent in 102 (40%). The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion was 13% (20 of 153) and 48% (49 of 102), respectively (P= 0.0001 by the chi-square test). When these were divided further by lung zones, triple matches with decreased perfusion and triple matches with absent perfusion in the upper–middle lung zone were associated with a prevalence of 0% (0 of 44), and 25% (9 of 36), respectively. The prevalence of pulmonary embolism in areas of triple matches with decreased perfusion and triple matches with absent perfusion in the lower lung zone was 18% (20 of 109), and 61% (40 of 66), respectively.ConclusionsA V–Q/chest radiographic match is less likely to represent pulmonary embolism if perfusion is decreased rather than absent. The overall prevalence of pulmonary embolism associated with all triple matches in all lung zones varied from very low (0% in this series) to upper intermediate (61%), depending on whether perfusion was decreased or absent and also on the location of the triple match.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Sphincter of Oddi dysfunction is an underdiagnosed but important clinical condition. It should be considered in the differential diagnosis of biliary pain when the gallbladder sonogram shows no evidence of gallbladder disease. Hepatobiliary scanning (Tc-99m dimethyl iminodiacetic acid) may provide valuable information in the evaluation of these patients and may be helpful in monitoring response to treatment.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Acute graft-versus-host disease (GVHD) usually involves the skin, gastrointestinal tract, and liver. A 47-year-old woman with fever of unknown origin was referred for a Ga-67 scan. The study showed diffuse uptake of Ga-67 throughout the skin. Subsequently, a skin biopsy confirmed the diagnosis of acute GVHD. The incidence, diagnosis, and pathophysiology of the dermatitis in acute GVHD are discussed.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

A man with small-cell carcinoma of the lung underwent a Tc-99m red blood cell gastrointestinal bleeding study because he had a tarry stool. In his first-pass study, there was early filling of the radiotracer in the middle and lower portion of the inferior cava; in addition, the study revealed a distorted and distended inferior vena cava along with an abdominal aortic aneurysm. Collateral circulation of the trunk was noted in the subsequent blood-pool images. A subsequent radionuclide superior vena cava study confirmed superior vena cava obstruction just above the entrance to the right atrium. Contrast-enhanced computed tomographic scans of the chest showed that the superior vena cava was compressed completely by the mediastinal tumor mass and that collateral circulation was present. Development of collateral circulation after superior vena cava obstruction in this patient allowed venous blood to return to the right atrium through the inferior vena cava. Thus, early filling of the inferior vena cava on radionuclide first-pass studies of the abdomen may serve as a sign of superior vena cava obstruction.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

PurposeProstaglandins play important roles in renal physiology and in the development of renovascular hypertension. In a recent study, inhibition of renal prostaglandin synthesis was found to be useful for detecting renovascular hypertension using renal scintigraphy. In the current study, the authors evaluated the role of aspirin (an inhibitor of prostaglandin synthesis) and compared it with Tc-99m DTPA captopril renal scintigraphy (CS).Materials and MethodsTwenty-five patients were examined with Tc-99m DTPA in a three-step manner: a baseline study, CS, and aspirin scintigraphy (AS). Each scintigraphic study was interpreted visually and according to the renogram curve patterns. Semiquantitative parameters (Tmax, renal indices [%], 20-minute/max count ratio, glomerular filtration rate) were also calculated. Plasma renin activity was determined for each study. The blood pressures of all patients were measured during AS. All patients had a contrast-enhanced angiogram that was used as the reference test.ResultsThree groups of patients were observed based on the scintigraphic and angiographic results. In each group, no difference was observed in blood pressure after aspirin administration. In group 1, seven patients had normal angiographic and scintigraphic results. In group 2, eight patients had angiographically confirmed renal artery stenosis (RAS). In 6 patients (mean, 47% RAS), both AS and CS were negative for RVH. In the remaining two patients with RAS (mean, 83% stenosis), the kidneys were atrophic on the stenotic side, and thus the kidneys did not respond to the interventions. No difference was observed in plasma renin activity in groups 1 and 2. Group 3 included 10 patients who had angiographically confirmed RAS (mean, 86%). In 9 patients, both CS and AS were positive for RVH. In the remaining one patient, scintigraphic results were falsely negative. Statistical analyses performed for semiquantitative parameters did not reveal any significant difference in this group, although there was a tendency toward prolonged Tmax values after captopril and aspirin administration. In four cases, unexpected elevation of plasma renin activity was observed in group 3.ConclusionsThese data indicate that AS with Tc-99m DTPA is an alternative for CS. It has the advantage of having no effect on blood pressure and does not require that angiotensin-converting enzyme inhibitors be discontinued. Although in this study 9 of 10 patients had correct diagnoses of RAS, further studies, especially using tubular agents with the calculation of parenchymal transit time, might provide valuable information in this patient group. An ongoing study is being performed in the authors’ institute.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

A lumbar bone densitometry examination was performed in a patient with severe low back pain but no pathologic findings on initial laboratory and radiologic investigations. The bone mineral density of the spine was in the low-normal range (90.5% age matched), with the L4 vertebra bone mineral density less than the others, whereas image analysis showed a defect in the right part of its body. Additional radiographs confirmed this finding, which was proved to be a metastatic lesion from a primary lung cancer. Although not intended for diagnosis, the results of image analysis of bone densitometry should be evaluated carefully.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

PurposePositron emission tomography (PET) with fluorine-18 fluorodeoxyglucose (F-18 FDG) is used for the noninvasive monitoring and grading of primary brain tumors. Here the FDG uptake is positively correlated with the malignant extent of the lesion and thereby negatively correlated with patient survival. Little is known about the FDG PET features of primary brain tumors in children, such as mixed neuronal-glial tumors.MethodsThe authors describe a 13-year-old boy who had partial complex seizures since early childhood caused by a brain tumor in the left temporal lobe.ResultsMagnetic resonance and computed tomographic examinations yielded uncharacteristic results: mixed density, marked calcifications, little contrast enhancement, a nearly absent mass effect, and no edema. The FDG PET scan revealed a large hypermetabolic tumor, with a tumor: contralateral gray matter FDG uptake ratio of 1.45. In contrast to this intense hypermetabolism, the pathologic analysis after gross total resection revealed a low-grade ganglioglioma (WHO grade I), which is usually associated with an excellent prognosis.ConclusionsMixed neuronal-glial tumors such as gangliogliomas must be considered in making differential diagnoses by judging hypermetabolic FDG PET scans in young patients with brain tumors in the presence of uncharacteristic imaging features.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

A patient with stage D3 prostate cancer was given 11 separate doses of samarium-153 lexidronam (Sm-153 ethylenediaminetetramethylene phosphonate) of 1 mCi/kg (37 MBq/kg) in a period of 28 months for bone pain from metastases. With the first five doses, Sm-153 lexidronam clearly reduced his bone pain and improved his quality of life, as determined by pain-assessment scores and the patient’s self-assessment of its effect on his ability to perform activities of daily living. With doses 6 through 11, pain at baseline was on average less, and as a result beneficial effects after treatment were not as apparent. Samarium-153 lexidronam produced transient decreases in the leukocyte and platelet counts, but these never became low enough to cause clinical concern. This case shows both the efficacy and the safety of Sm-153 lexidronam in repeated treatments for metastatic bone pain in patients with prostate cancer.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID

摘要:

Early detection and prompt treatment of breast cancer are the main tools to decrease mortality rates. Several diagnostic techniques such as mammography, magnetic resonance imaging, and ultrasound are used, but none of these are conclusive. The authors describe a 56-year-old woman who was suspected of having breast cancer on mammography. Tc-99m MIBI scintimammography showed a small mass with elevated radiotracer uptake located near the pectoral muscle of the patient’s left breast. The possible tumor was confirmed with fine-needle aspiration biopsy. After the diagnosis was established, the patient did not allow any treatment. Eighteen months later, a second scintimammography was performed, showing a large mammary tumor with a high radiotracer uptake, a new small lesion located in the left upper quadrant, and axillary lymph node involvement. Chemotherapy treatment was instituted and after treatment, Tc-99m MIBI scintimammography was normal. This case report provides further evidence for Tc-99m MIBI scintimammography for the detection of breast cancer as well as to evaluate the response to chemotherapy.

ISSN:0363-9762    

出版商:OVID    

年代:2000

数据来源: OVID