摘要:

The efficiency and accuracy of a functional imaging technique in the detection of ischemic osteopathy is reviewed over a 10-year period. The study includes 161 patients who had trauma, 101 patients who had suspected Perthes disease, 43 patients who had dysbarism, and 22 patients who had renal transplants on steroid immunosuppressive therapy. After intravenous injection of 7.7 MBq kg-1Tc-99m HDP data were collected on all patients during the first 20 minutes, accretion rate functional images were produced, and static bone scans performed after 3 hours. All patients were followed up until a definitive diagnosis (clinical and radiologic) of avascular necrosis or osteochondritis was confirmed or denied. Of the 327 patients studied, 114 had positive accretion rate images and 213 negative accretion rate images. There were 8 false-positive scan results and 2 false-negative scan results. The overall predictive accuracy was 97% (disease prevalence 33%) with a sensitivity rate of 98% and a specificity rate of 96%. The authors conclude that the technique is a valuable predictive diagnostic indicator for ischemic osteopathies.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Purpose:To evaluate the distribution and degree of radioactivity on sequential Tc-99m methylene diphosphonate (Tc-99m MDP) scans in the diagnosis of postoperative loosening in asymptomatic patients who underwent cementless total hip replacement.Material and Methods:Tc-99m MDP scans were obtained every three months where possible, for one year in those patients who underwent total hip replacement using a Harris Galante cementless prosthesis. Eighty-three scans from 45 patients were obtained. Uptake was assessed within the five periprosthetic zones (zone 1: greater trochanter; 2: lateral stem of the prosthesis; 3: tip of the prosthesis; 4: medial stem of the prosthesis; and 5: lesser trochanter) using an arbitrary 5-point grading system. Grade 1 indicated normal uptake and Grade 5 indicated highest uptake. The grade of uptake within each zone was then analyzed against their postoperative ages.Results:The radioactivity regressed to Grade 1 or 2 from Grade 4 or 5 within 12 months after cementless total hip replacement in 87.5% and 93.8% of patients in zones 2 and 4, respectively. Even though the radioactivity within zones 1, 3, and 5 tended to decrease, persistent elevation of activity (over grade 2) lasted up to 12 months after surgery in 31% or 37% of the patients.Conclusion:The radioactivity after cementless total hip replacement tended to regress in proportion to the postimplant age. The regression rate varied depending on the periprosthetic zones.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Background:Thyroid gland ectopy is the most common cause in infants with congenital hypothyroidism (CH). Its association with iodine organification defect, as suggested by positive perchlorate discharge test (PDT) has been reported. However, whether such an association represents a true or transient defect has not yet been determined. This finding has an important clinical, epidemiological, and genetic implications.Objective:To determine the natural history of iodine organification defect in patients with CH caused by thyroid ectopy detected by neonatal screening.Design:Prospective longitudinal study. Setting: King Khalid University Hospital, Riyadh, Saudi Arabia.Patients and Methods:PDT was performed, at the time of diagnosis and follow-up, in infants who showed an enlarged ectopic thyroid gland with a Tc-99m pertechnetate uptake of 2% or more.Results:Of 115 neonates with ectopic thyroid glands, 19 showed an enlarged gland with Tc-99m uptake ranging from 2 to 3.2%. Perchlorate discharge test was performed in 13 of these and was consistent with iodine organification defect in nine. Repeated PDT in seven patients showed normal values.Conclusion:The results of the authors' study indicate the transient nature of the iodine organification defect and suggest that a delay in the developmental of synthetic mechanisms occur in the dysgenetic glands.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The aim of this study was to establish the usefulness of Tc-99m human polyclonal immunoglobulin (HIG) imaging in a group of patients who were suspected of having inflammatory bowel disease (IBD). The authors performed 30 scans (15 with Tc-99m HMPAO leukocytes and 15 with Tc-99m HIG) on 15 patients with IBD. Ten patients had Crohn's disease and five had ulcerative colitis. The sensitivity of Tc-99m HIG scintigraphy for detecting IBD was 33%, while the sensitivity of Tc-99m HMPAO leukocyte imaging was 100%. The Tc-99m HMPAO leukocyte imaging also detected a larger number of affected segments and provided better image quality of the extent of disease than Tc-99m HIG. On the basis of these results, the authors believe that Tc-99m HIG imaging is not a useful technique in the evaluation of patients with IBD, in the identification of location, or the extension or degree of disease activity.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Ga-67 and abdominal CT scans of a 72-year-old woman who had malignant lymphoma before, during, and after gallium nitrate/hydroxyurea combination therapy are presented. Disappearance of Ga-67 uptake by the tumor during this treatment despite continuing CT evidence of disease and reappearance of Ga-67 scan abnormalities after cessation of therapy suggests that caution should be exercised when interpreting results of Ga-67 scintigraphy for the detection of tumor viability during gallium nitrate/hydroxyurea therapy.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

The aim of this study was to determine the usefulness of radioimmunoscintigraphy (RIS) with monoclonal antibodies (MAb) to detect primary ocular melanoma and its relapses and metastases. The authors studied nineteen patients (9 men and 10 women), aged 24 to 74 who were suspected of having ocular pigmented tumors by means of RIS. The authors used F(ad)2-fragments of monoclonal antibodies against high molecular weight-melanoma associated antigen, labeled with Tc-99m (activity 370-555 MBq). Planar and SPECT imaging were performed at 6, 12, and 24 hours. The sensitivity of the method was 78.6%; the specificity was 100%; and the accuracy was 84.2%. The results obtained suggest that RIS is a highly specific and sensitive technique in the differential diagnosis of malignant ocular melanoma.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Radioimmunoscintigraphy (RIS) with Tc-99m labeled 170H.82, an intact murine monoclonal antibody (MAb) was performed in 27 patients with suspected primary, recurrent, or metastatic breast cancer. For radioimmunoimaging the authors used a double-headed, high-resolution gamma camera. The lesions detected by RIS were evaluated by histopathology, and for metastatic disease by CT, MRI, and bone scan. If the evaluation was made lesion by lesion, RIS with Tc-99m MAb 170H.82 showed 23 true-positive results, 3 false-negative results, 9 true-negative results, 3 false-positive results for primary and recurrent disease; sensitivity was 88% and specificity was 75%. In patients with distant metastases, detection rate was 67% (12 true-positive results and 6 false-negative results). All patients had normal baseline values for human anti-mouse antibodies (HAMA) and 6 weeks after RIS with 3 mg MAb, only 2 of 23 patients had developed a HAMA response (9%). No adverse effects were observed. The authors' clinical experience shows that RIS with MAb 170H.82 is a valuable additional method for detecting breast cancer, especially in patients with uncertain primaries or scar tissue after breast conserving treatment in which differential diagnosis is very difficult.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Scintigraphic diagnosis of a liver hemangioma may be difficult when its size approaches the spatial resolution of a gamma camera, and it may not be visualized on a Tc-99m tin-colloid liver SPECT study. The contribution of Tc-99m labeled RBC scintigraphy is shown in a patient with a liver hemangioma discovered during laparoscopic cholecystectomy for chronic cholecystitis. Despite negative CT, US, and Tc-99m tin-colloid SPECT of the liver, Tc-99m labeled RBC SPECT disclosed a focus of increased activity consistent with the hemangioma.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Tc-99m pertechnetate scintigraphy was compared with Tl-201 chloride and Ga-67 citrate to evaluate the avidity of Tc-99m pertechtate for malignant soft-tissue tumors. Twenty-three patients with malignant soft-tissue tumors underwent scintigraphic studies. All 23 received Tc-99m and Tl-201, whereas 14 also were injected with Ga-67. In 21 (91%) of the 23 patients, Tc-99m accumulated extensively in the tumors. Tl-201 accumulated in 12 (52%) of the 23 tumors. Ga-67 accumulated in only 5 (36%) of the 14 tumors. The avidity of Tc-99m for myxoid tumors was markedly different from the other two agents. Tc-99m accumulated in all eight myxoid tumors, while neither Tl-201 or Ga-67 showed marked accumulation except for one patient with increased accumulation of Tl-201. This study shows that Tc-99m pertechnetate has the potential to localize malignant soft-tissue tumors and may be useful in the evaluation of these tumors.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID

摘要:

Objective:Two routine lung SPECT studies showed what appeared to be uptake within the gallbladder. This finding was confirmed on coronal views and three-dimensional reconstruction. There was no contamination or problem with the radiopharmaceutical quality control. The patients had not had any prior nuclear procedures. Gallbladder visualization on routine lung imaging has not been previously observed. The purpose of this study was to ascertain the incidence of gallbladder uptake and to determine a possible mechanism.Methods:Fifty-four patients referred for routine lung perfusion imaging were examined. At the end of the lung imaging, an anterior and/or right lateral 3-5 minute view of the abdomen was obtained. Patients too ill for additional imaging or those with prior cholecystectomies were excluded.Results:Nineteen of the 54 patients showed activity within the gallbladder. Activity within the gut, kidneys, and urinary bladder also were observed.Conclusion:Gallbladder activity after Tc-99m macroaggregated albumiun injection for lung perfusion studies, is a fairly common finding.

ISSN:0363-9762    

出版商:OVID    

年代:1997

数据来源: OVID