摘要:

Previous results from tests on a limited number of patients suggested that the combination of relatively normal hepatocyte clearance, prolonged parenchymal transit time, and eventual passage of radiotracer into the intestine or gallbladder without evidence of biliary tract dilatation were relatively specific for intrahepatic cholestasis. We reevaluated the specificity of cholescintigraphy for the diagnosis of intrahepatic cholestasis in an unselected group of patients from a general hospital. Sixteen patients had the cholescintigraphic findings of intrahepatic cholestasis and an established diagnosis of biliary tract dilatation or nondilatation by ultrasound, ERCP, or intraoperative cholangiography. Using 6 mm as the upper limits of normal for the diameter of the common hepatic duct by ultrasonography resulted in a specificity of 63% (10 correct out of 16); using 6 mm plus 1 mm for every decade over 60 years of age gave a specificity of 75% (12 correct out of 16); and using the more liberal criterion of 8 mm as the upper limits of normal increased the specificity to 81 % (13 out of 16). The data suggest that cholescintigraphy alone is unreliable in differentiating intrahepatic cholestasis from extrahepatic obstruction, even when the obstruction is partial and radiotracer eventually passes through the extrahepatic biliary tract.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Visualization of a “dilated cystic duct” during standard hepatobiliary imaging represents a potential source of false-negative cholescintigraphy. Intravenous morphine, commonly used to shorten study time and improve the specificity of hepatobiliary imaging, may, by virtue of its pharmacologic/physiologic actions, accentuate the appearance of a “dilated cystic duct.” We present a case of transient cystic duct visualization following morphine administration in a patient with an obstructing cystic duct calculus.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

A rare false-positive red blood cell scintigram occurred in a 49-year-old woman with two metastases from a primary adenocarcinoma of the sigmoid colon. Although the blood flow and static planar images were unremarkable, a 1-hour postinjection SPECT study showed a focus of increased activity in the inferior right lobe and a second photopenic focus in the dome. Following a trisegmentec-tomy, pathologic examination revealed the two metastases with no evidence of a hepatic hemangioma. Microscopy, however, showed a discrete area of nonspecific reactive changes (focal sinusoidal dilation and congestion) immediately adjacent to the metastasis in the inferior right lobe. It is postulated that the SPECT focus of increased activity occurred secondary to the labeled blood pool within the area of sinusoidal dilation, rather than within the adjacent metastasis.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Photopenic osseous lesions are a well-recognized but unusual manifestation of metastatic disease on bone scintigraphy. Common primary tumors giving rise to such lesions include lung, breast, renal, and thyroid. This case report illustrates multiple “cold” osseous metastases from aggressive penile squamous cell carcinoma without radiographic destruction.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

A scintigraphic study was carried out on 48 patients presenting with palpable soft tissue masses. Imaging was carried out using Tc-99m DTPA in three phases (dynamic, blood pool after 5 minutes, followed by late scans after 2 hours). The resultant uptake of the agent was categorized as consistently positive (14 cases), initially positive but progressively negative (7 cases), initially negative but progressively positive (7 cases), and consistently negative (20 cases). Histopathologic examinations were carried out for ail cases following biopsy. A variety of malignant and benign masses were found to localize DTPA, whereas all masses that did not concentrate the agent were proven to be lipomas. In order to determine whether the uptake of DTPA bore any relationship to blood flow, additional studies using Tc-99m labeled red cells were carried out on 15 patients with soft tissue tumors. There was no correlation between blood flow or pooling and the degree of Tc-99m DTPA uptake by the palpable masses. The sensitivity of DTPA uptake as indicative of nonlipomatous tissue was 100%, and its specificity was 91%. The predictive probability that a lesion was a liopoma if there was no DTPA uptake at any phase was 100%.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

The aim of this study was to assess the diagnostic value of five biological markers—prostate acid phosphatase (PAP), prostate specific antigen (PSA), tartrate resistant (Tr-ACP), and tartrate labile (TI-ACP) acid phosphatases, and alkaline phosphatase bone isoenzyme (B-ALP)—for the detection of bone metastases in patients with prostate carcinoma. Using the Tc-99m HMDP bone scans of 80 patients scored from 0 (normal) to 2 (diffuse bone involvement) as the “gold standard,” a receiver operating characteristic (ROC) analysis was performed. This method allows the determination of different threshold values (corresponding to different couples of sensitivity and specificity) for the assays. An ROC curve comparison was also performed. Results show that B-ALP is the best test for such detection (area under the ROC curve = 0.93; Spearman Rank correlation with bone scan r‘ = 0.81). Among the other markers, PSA was found to be the best (area under the ROC curve = 0.81; Spearman Rank correlation with bone scan r’ = 0.58). In addition to the prostatic tumor markers (PSA and PAP), we suggest the use of the low-cost B-ALP assay in the follow-up of prostate carcinoma patients to determine the optimum moment to perform a bone scan. A normal result of this assay indicates a very low probability of bone metastasis; conversely, raising of B-ALP concentration must lead to a bone scan.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

This study was designed to evaluate the usefulness of the bone tracer Tc-99m MDP for quantitative assesment of relative renal function as compared with renal imaging radiotracers used for that purpose. Differential renal function, i.e., the percent contribution each kidney makes to global renal function, was determined prospectively in 15 consecutive patients using Tc-99m MDP and a renal radionuclide tracer, either Tc-99m DTPA or Tc-99m GHA. Differential function was computed in all cases from the early (1–3 minutes) renal uptake of the tracers by region-of-interest analysis of the computer-acquired data. There was a high correlation between values of differential function obtained with Tc-99m MDP and those obtained with Tc-99m DTPA or Tc-99m GHA (r = 0.98,P< 0.0001). Qualitative assessment of the images revealed equivalent scintigraphic patterns in all patients. It is concluded that the early characteristics of renal handling of Tc-MDP are sufficiently similar to those of Tc-DTPA and Tc-GHA so that accurate estimates of differential renal function are possible with this agent, and that Tc-MDP-determined renal differential most likely reflects differential glomerular filtration rate.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Thyroid scintigraphy was performed in 69 consecutive infants with permanent primary congenital hypothyroidism (CH) detected by systematic neonatal thyroid screening using a rectilinear scanner or a gamma camera 15 minutes after the intravenous injection of 250 μCi Tc-99m sodium pertechnetate, immediately after the infants were fed. Immobilization of the infant in a supine position with the neck in hyperextension was achieved by a vacuum cushion without any sedation. Thyroid scintigraphy showed thyroid ectopia in 43 of the 69 CH infants, thyroid agenesis in 19, and goiter in the last 7 infants, respectively. The images were easily interpretable in all cases, even in very small ectopic glands in the lingual area, as there was no interference with extra-thyroidal uptake of the tracer, especially by the salivary glands. Our experience indicates that thyroid scintigraphy in the CH newborns can be performed immediately at the time of diagnosis of CH without technical difficulties. As thyroid scintigraphy is the only procedure allowing the distinction between thyroid agenesis and ectopia, and as the neurointellectual prognosis might be lower in the former than in the latter situation, thyroid scintigraphy in CH newborns contributes not only to the diagnosis but also the prognosis of the disorder.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

Human immunodeficiency virus (HIV) infection is frequently complicated by a variety of disease processes affecting the central nervous system (CNS). One of them is AIDS dementia complex (ADC), which, in the absence of opportunistic infection, is believed to be caused by HIV itself. ADC is characterized by a constellation of cognitive, motor, and behavioral symptoms that progressively get worse. This study was coined to recruit AIDS patients without any opportunistic CNS infection but with signs of CNS abnormality as evidenced by behavioral and subtle motor changes, then to categorize them into five stages, and finally to perform the cerebral blood flow scan using Ceretec. The aim of this study was to correlate the abnormalities of the brain scan with the different stages of ADC. Five patients were analyzed, with dementias ranging from mild to severe according to Price's classification. After confirming the absence of CNS opportunistic infections and AIDS associated malignancies by CT of the brain, the patients underwent psychiatric evaluation and brain scans. The SPECT scans were very sensitive in showing uptake defects in the brain, even in the early stages of ADC. The blood flow defects were more pronounced in the later stages, while the CT scans remained negative except in patients with the most severe dementia.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

This report describes a new approach to the evaluation of neuroleptic effects on regional brain function. Using Tc-99m HMPAO SPECT imaging, consecutive brain perfusion studies before and after acute haloperidol administration were performed on three schizophrenic patients and two normal volunteers. The antipsychotic drug ameliorated the hypoactivity in the frontal lobe and suppressed the hyperactivity in the temporo-occipito-pa-rietal lobe selectively in the dominant hemisphere in the schizophrenic patients. It did not exert a significant influence on the brain perfusion pattern in normal volunteers. This nuclear medicine technique seems to be useful for the evaluation of drug effects in psychiatric diseases.

ISSN:0363-9762    

出版商:OVID    

年代:1991

数据来源: OVID