摘要:

Lymphoscintigraphy is increasingly used to identify the first draining node (sentinel node) in patients with malignant melanoma or breast cancer. If the sentinel node is tumor free then the remainder of the nodes in that specific nodal bed are likely to be free of metastases. Localization and biopsy of the sentinel node with an intraoperative surgical probe may obviate more radical lymph node dissection. Lymphoscintigraphy is conventionally performed by injecting the radioactive tracer in the four quadrants around the primary tumor and imaging the appropriate nodal beds approximately 30 minutes later. The visualized node nearest the tumor usually is assumed to represent the sentinel node. To test this assumption, a dynamic acquisition was obtained in 16 patients with malignant melanoma to determine if the node nearest the tumor was actually the first draining node. In one of 16 patients, the radioactive tracer injected around a thigh melanoma drained first to an inguinal node and then drained inferiorly to a second inguinal node located closer to the tumor. The distinction between the sentinel and satellite (secondary draining nodes) may have important clinical implications regarding the number of nodes that require surgical excision. In summary, static images do not define the pattern of lymph flow and the node nearest the tumor is not necessarily the sentinel node. Failure to obtain dynamic images may lead to misdiagnosis of the sentinel node in a small percentage of patients.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

To evaluate whether In-111 capromab pendetide (an antibody conjugate directed to a glycoprotein found primarily on the cell membrane of prostate tissue) radioimmunoscintigraphy can localize residual or metastatic prostatic carcinoma in 15 patients after prostatectomy and lymphadenectomy for prostatic carcinoma with rising serum prostate-specific antigen. One patient with 0.6 ng/ml serum prostate-specific antigen had normal imaging results and 14 patients had scintigraphic evidence of residual prostatic bed or metastatic prostatic carcinoma. Two patients with borderline abnormal bone scans had abnormal activity in the same regions on In-111 capromab pendetide images. All patients had negative radiographic abdominal and pelvic cross-sectional prestudy images, and there were no adverse effects related to In-111 capromab pendetide infusion and little human antimouse antibody response.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Fifty female patients with acute abdomen and suspected appendicitis but atypical findings were included in this study. After intravenous injection of Tc-99m HMPAO-labeled WBCs, serial anterior abdominal/pelvic images at 30, 60, 120, and 240 minutes were obtained by a gamma camera. Any abnormal localization of WBC accumulation in the right lower quadrant of the abdomen with equal to or greater than bone marrow activity was considered as a positive scan. Thirty patients had positive WBC scans and underwent laparotomy, 28 had proven appendicitis, and 2 were not related to appendicitis. Twenty patients had negative WBC scans, 2 patients underwent laparotomy and were proved to have appendicitis. The remaining 18 patients did not undergo surgery and revealed no evidence of appendicitis after follow-up. The overall sensitivity, specificity, accuracy, and positive and negative predictive values for WBC scans to diagnose appendicitis is 93.3%, 90.0%, 92.0%, 93.3%, and 90.0%, respectively. In conclusion, Tc-99m HMPAO-labeled WBC imaging provides a rapid and highly accurate method for diagnosis of appendicitis in female patients with equivocal clinical examinations.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Assessment and characterization of the thymus by various imaging methods have been extensively described. The authors report increased uptake of 2-(18)Fluoro-2-deoxy-D-glucose (FDG) in the normal thymus gland of patients between the ages of 2 and 13 years. Most of these patients had PET scans for various oncologic conditions and had no clinical problems referable to the thymus gland. This uptake assumes an important role when evaluating mediastinal uptake in whole-body PET scans in pediatric oncology patients to avoid false-positive interpretation.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

A bone scan is frequently obtained in patients with breast cancer for evaluation of possible metastatic bone disease or for evaluation of response of known metastases to treatment. These patients commonly wear breast prostheses after unilateral or bilateral mastectomies. On some bone scans, the authors have observed artifacts resulting from certain breast prostheses. In particular, in the patient described, a weighted breast prosthesis was not removed during Tc-99m HMDP bone scanning and was interpreted as being permanent pacemaker or defibrillation unit. The scintigraphic appearance of several commonly used, commercially available weighted breast prostheses is discussed.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

During the last two decades, there has been a trend to use low-dose I-131 ablation therapy in patients with thyroid carcinoma without metastases. However, information regarding the incidence of acute adverse reactions in patients after low-dose radioiodine therapy has not been reported. In this study, the acute radiation effects after low-dose radioiodine ablation therapy in postsurgical differentiated thyroid cancer patients was evaluated. Fifty-six patients with differentiated thyroid cancer were prospectively evaluated. None of these patients had evidence of a distant metastasis. All patients received 40 mCi (1480 MBq) I-131 MIBG orally and were evaluated for symptoms and signs by a physician on the second and seventh days after therapy. Xerostomia and nausea were the most common complaints with the same incidence rate of 5.35%. Gastralgia occurred at a frequency of 3.57%. Pain in the thyroid bed, tenderness over a parotid gland, submandibular glands, change in taste, and vomiting all were found at a frequency of 1.78%. Maximum reactions generally occurred 24-48 hours after therapy. All the symptoms except for xerostomia resolved completely in most patients within a week. In comparison with high-dose ablation therapy published in the literature, the incidence of radiation reactions in low-dose radioiodine therapy was much lower. It was concluded that in patients without lymph node or distant metastases, low-dose I-131 MIBG therapy may be recommended to avoid the high incidence of local complications after high-dose treatment.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Increased Tl-201 lung-heart ratio after treadmill exercise or pharmacologic stress is an indicator of left ventricular dysfunction. After pneumonectomy, it is not reliable because of increased pulmonary circulation in the remaining lung. The authors present an example of normal stress TI-201 myocardial perfusion imaging with an increased lung-heart ratio of TI-201 uptake.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

The relationships of clinical diagnosis, the effect of blood chemistry, and the clinical implication of increased Ga-67 citrate uptake in the bone marrow of patients with signs and symptoms of fever of unknown origin were studied. Based on intensity of Ga-67 citrate uptake in bone marrow, patients were classified as follows: type 1 when there was no evidence or very faint bone marrow uptake in the vertebrae, type 2 when mild to moderate, type 3 when uptake was severe. The relationships of WBC count, hemoglobin, hematocrit, serum iron, and unsaturated iron-binding capacity with the occurrence of increased bone marrow uptake in the different groups were noted. Analysis of variance with Fisher's protected least significant difference was used. APvalue of less than 0.05 was considered significant. The results showed significant differences between types 1 and 2 and between types 1 and 3 for WBC counts, hemoglobin, and hematocrit levels. Serum iron concentration and unsaturated iron-binding capacity, however, did not show any significant differences. Significant changes in WBC count, hemoglobin and hematocrit in patients with fever of unknown origin were accompanied by a varying intensity of Ga-67 citrate uptake in the bone marrow.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

Lack of dystrophin, a protein localized to the inner surface of the sarcolemma of the muscle fiber, is the cause of Duchenne type muscular dystrophy. Plasma membrane damage of the muscular fiber occurs, followed by Ca++ influx into the fibers. There is severe mitochondrial damage in dystrophic but still viable fibers. Five children aged 5-7 years were studied with MRI, Tl-201, and Tc-99m sestamibi scintigraphy of the thighs. These three methods showed that the sartorius is the least damaged muscle in Duchenne type muscular dystrophy. MRI showed mild damage of adductors and quadriceps; Tl-201 scintigraphy showed a marked reduction of radioactivity in the same muscles; Tc-99m sestamibi uptake occurred only in the sartorius muscle; the quadriceps was not imaged and adductors showed a faint image. A decrease of water in muscular fibers as well as fatty fibrous substitution, occurs after death of the fibers, whereas plasma membrane and mitochondrial damage reduced the uptake of tracers when the fiber is still viable. The interesting mismatch between sestamibi and Tl-201 can be explained by considering that the cellular mechanism of uptake and retention of Tc-99m sestamibi involves both plasma membrane and mitochondria, whereas the uptake of Tl-201 is only affected by plasma membrane damage.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID

摘要:

A 17-year-old girl with Hodgkin's lymphoma showed significant uptake of Ga-67 at a site diagnosed as fibrous dysplasia by Tc-99m scintigraphy and radiographs of the lower extremities. Fibrous dysplasia is a skeletal developmental anomaly of bone-forming mesenchyme in which osteoblasts do not undergo normal morphologic differentiation and maturation. It may affect one or several bones and is not hereditary. Its cause is unknown.

ISSN:0363-9762    

出版商:OVID    

年代:1996

数据来源: OVID