摘要:

Primary or relapsing hyperparathyroidism should not be considered a result only of benign conditions like adenoma or hyperplasia (primary or secondary). Parathyroid carcinoma is often the real cause but, because of its rarity, sometimes it is either overlooked or misdiagnosed. Even histologic classification can be erroneous. Distant metastases or ectopic location of the tumors are another potential cause of misdiagnosis, especially when management is decided without the help of diagnostic imaging modalities, particularly those related to the functional aspect of the tumors or their metastases, such as the Tl-201/Tc-99m subtraction scan and the Tl-201 whole body scan.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Although many radiopharmaceuticals are “targeted” for specific tissues or organs, they may be incorporated into nonspecific sites to the extent that they are readily diffusible. There may be local hyperemia with “leaky” neovascularity or capillaries and perhaps also diminished lymphatic or venous removal from the affected area. Two cases are reported in which abscesses were visualized serendipitously. One was visualized on a Tc-99m MDP bone scan following nephrectomy, the other on a patient with a pelvic abscess and nonvisualized left kidney but with enhancement of the rim of a large pelvic abscess.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Seven children (aged 7 to 16 years) with confirmed osteomyelitis underwent imaging with Tc-99m HMPAO labeled leukocytes and with Tc-99m diphosphonates. The patients were scanned at ½ hour and at 3 hours. The scans were evaluated visually, and the lesion-to-normal bone ratios were quantitated. All the lesions on leukocyte scans and six out of seven lesions in bone scans were readily detectable ½ hour after injection of the radiopharmaceutical, but 3 hours is the better imaging time. In quantitative analysis, the lesion-to-normal bone ratio increased with leukocytes significantly higher than with the bone scans (P< 0.05). When the scintigraphic findings were compared with surgical and radiologic results, the leukocyte images detected and localized lesions better than the bone scans. According to these preliminary results, Tc-99m HMPAO labeled leukocytes seem to offer a rapid and accurate method for detecting bone infections.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

The reported frequency of prosthetic vascular graft infections after reconstructive vascular surgery is low. However, it is a serious and potentially catastrophic complication of this treatment, with high morbidity and mortality rates. Effective therapy involves graft excision and replacement. Tc-99m HMPAO labeled leukocyte scintigraphy appears to be an accurate method of detecting prosthetic vascular graft infections. The value of leukocyte scanning is illustrated by two case reports.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Clinical applications for Tc-99m HMPAO labeled red blood cells have not been previously reported. The authors describe a simple, aseptic, closed, one-step centrifugal procedure for red blood cell labeling with Tc-99m HMPAO and isolation from whole blood, and they report the preliminary results of using these labeled red blood cells to detect acute gastrointestinal bleeding in 11 patients. Whole blood was radiolabeled with Tc-99m HMPAO preparation and blood cells were separated by centrifugation (30 min, 200 g, 20°C) using Polyprep density gradient medium. Red blood cells contained about 50% of the radioactivity. Four out of the 11 patients imaged with a gamma camera after reinjection of labeled autologous red blood cells showed abnormal accumulation, suggesting gastrointestinal bleeding that was verified at surgery and was at the site of abnormal activity in all cases. Image quality with Tc-99m HMPAO was comparable to that of Tc-99m pertechnetate labeled pretinned red blood cells. Tc-99m HMPAO can be used as a red blood cell labeler; however, its elution rate from red blood cells limits its applicability in some investigations.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Tc-99m HMPAO SPECT is more likely to detect a stroke in early stages than CT. However, a conventional HMPAO SPECT study takes at least 30 minutes to complete. This paper compares fast Tc-99m HMPAO SPECT scans and conventional Tc-99m HMPAO SPECT scans with respect to spatial resolution and diagnostic efficacy in vitro and in a small series of patients, respectively. The spatial resolution of fast Tc-99m HMPAO SPECT did not match that of images obtained from conventional SPECT, though the difference proved to be of no clinical significance. Since fast SPECT requires only one-fourth to one-fifth the time necessary for conventional SPECT, it may be more suitable for investigating cases of acute stroke in critical clinical situations.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Six patients with metastatic carcinoma of the penis underwent Ga-67 citrate scanning. Intense radioactive uptake was noted in the metastatic inguinal lymph nodes that was not influenced by the presence or absence of infection. There was a correlation between clinical improvement and decrease in abnormal groin uptake. The results reported here suggest the possibility of using Ga-67 citrate scanning in the staging, management, and follow-up of this relatively rare condition, although further experience is needed to establish its precise role.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

To evaluate the usefulness of Ga-67 citrate scintigraphy in the early detection of radiation pneumonitis, scintigrams from 103 patients who were treated with radiation therapy for lung cancer were retrospectively analyzed with regard to abnormal Ga-67 uptake after radiation therapy in sites other than the original or recurrent tumers. Sixteen (20%) of the 80 asymptomatic cases showed positive Ga-67 scintigrams. All of the other 23 symptomatic cases showed positive Ga-67 scintigrams. Thirteen (57%) of these 23 cases had negative chest radiographs although their Ga-67 scintigrams were positive. Detection of radiation pneumonitis by Ga-67 scintigraphy was significantly earlier than that possible by chest radiography (P< 0.01). These data suggest that Ga-67 scintigraphy is more useful and sensitive than chest radiography for the early detection of radiation pneumonitis.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

A man with a high-grade lymphoma had radiogallium imaging at 48 hours postinjection, revealing three distinct sites of uptake (neck and thorax). Unknown to the authors, the patient was given cytoxan, vincristine, and prednisone intravenously 27 hours after radiogallium administration. The images at 120 hours showed markedly reduced radiogallium activity at all three sites. Possible reasons for the loss of radiogallium from the tumor sites were presented.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID

摘要:

Technical error is not usually considered among the many possible causes of false-positive lung scans. A case is presented where the inadvertent injection of Tc-99m MAA through a Swan-Ganz catheter resulted in radionuclide imaging mimicking massive pulmonary embolism. After reinjection in a peripheral vein, a repeat perfusion scan showed unremarkable findings. Lack of the appropriate clinical presentation and the rarity of massive perfusion defects are important clues to recognizing this unusual but misleading situation.

ISSN:0363-9762    

出版商:OVID    

年代:1992

数据来源: OVID