摘要:

PurposeWith conventional planar imaging, preoperative anatomic localization of a sentinel lymph node is possible in only two dimensions. To improve spatial localization of sentinel lymph nodes, a dual-head camera equipped with a transmission source was used to create combined transmission–emission SPECT images in a patient with a malignant melanoma of the left forearm.MethodsLymph node scintigraphy was performed after injection of Tc-99m-labeled nanocolloid around the tumor site 1 day before operation. SPECT was performed using a gamma camera equipped with a transmission collimator system originally designed to correct attenuation. Transmission and emission images were created simultaneously, matched, and displayed in three dimensions.ResultsIn the combined emission–transmission images, the sentinel lymph node was clearly located in the left axilla. The lymph nodes could be identified during operation at the same location as that detected by SPECT. Based on preoperative information, the sentinel lymph node was identified rapidly and the extent and duration of the operation were minimized.ConclusionsThis method provides better anatomic information, especially in deep structures such as the axilla or pelvis. With accurate three-dimensional preoperative information, intraoperative access is quicker and less invasive for the patient.

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeIn-111 pentetreotide (Octreotide) is highly sensitive for detecting gastroenteropancreatic neuroendocrine tumors and their metastases. However, a lack of landmarks makes it difficult to localize them anatomically. To overcome this difficulty, the authors simultaneously obtained Octreotide and bone tomoscintigrams, in addition to standard planar images. They used a bicolor scale to display pairs of scintigrams to easily identify the distribution of both tracers.MethodsTwenty-one hours after Octreotide injection, Tc-99m MDP was also administered to the patients. Three hours later, dual-energy planar and tomographic data were acquired simultaneously. The latter were reconstructed using a filtered back-projection algorithm using a Metz filter. Both sets of data were displayed simultaneously using a bicolor scale, such that Octreotide data appear in green and bone data in red.ResultsPlanar, tomographic, and three-dimensional data were obtained. With this approach, foci of abnormal uptake are localized more precisely. Hard data can be transmitted easily to referring physicians, who appreciate this compact and efficient means to locate foci of abnormal uptake, especially during surgery planning. However, this method is not well suited to the visualization of small lesions with low Octreotide uptake because the intensity range is drastically reduced. Such lesions are better seen on Octreotide planar images and standard tomoscintigrams.ConclusionsThis approach, which involves only standard image processing, provides landmarks to easily localize significant Octreotide uptake. It can be implemented readily in most nuclear medicine workstations. It complements but does not replace the usual method to display Octreotide data.

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Persistent pain in the ankle after relatively minor trauma is common and usually resolves spontaneously. Two cases of persistent pain after minor trauma are presented that involved unusual characteristics of scintigraphic and magnetic resonance imaging, compatible with avascular necrosis of the talar body. This is a rare finding in the absence of steroid use or significant trauma to the foot. The unusual vascular anatomy of the talus is considered in the possible mechanism of injury.

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

Patients may be prepared for radioiodine diagnostic imaging by withdrawal of all thyroid medication or by the administration of extrinsic thyroid-stimulating hormone (TSH). Although purified human and bovine TSHs were used in the past, they are no longer recommended because of their adverse effects. Recently, a new extrinsic TSH called recombinant human TSH (rhTSH) was developed and is commercially available. It is a highly purified, recombinant form of the naturally occurring human TSH. It was introduced to decrease complications associated with temporary hypothyroid states required at times in the follow-up evaluation of patients with thyroid cancer. Although rhTSH is currently used for patient preparation in diagnosis only, its use in preparations for subsequent radioiodine therapy may be helpful in some clinical circumstances. The authors describe a patient with papillary thyroid cancer in whom a 2-day rhTSH protocol was used for diagnosis and extended for therapeutic purposes. The protocol was useful to obtain the diagnostic information needed to determine whether to treat, and it allowed rapid progress to therapy without further patient preparation. Until rhTSH is fully approved for both diagnostic and therapeutic uses, this modified 2-day protocol would allow patients with special clinical circumstances to be evaluated and treated rapidly.

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeAlthough left ventricular systolic function seems to be accurately represented on gated SPECT myocardial perfusion imaging, specific patterns of wall motion (WM) and thickening after coronary bypass graft surgery (CABG), demonstrated by other imaging methods, have not been characterized for gated SPECT myocardial perfusion imaging.MethodsGated SPECT myocardial perfusion imaging was studied in 30 consecutive patients after CABG (group 1) and 40 non-CABG patients–30 with normal stress perfusion studies (group 2) and 10 with known previous anterior wall infarction (group 3). Two expert readers evaluated epicardial and endocardial systolic WM. Regional WM and the thickening percentage were obtained using CEQUAL 20 segment bull’s eye analysis and compiled into regional values.ResultsQualitatively, the post-CABG patients had hypokinetic septum, a hyperdynamic lateral wall, and preservation of anterior WM. In 25 of 30 (83.3%) patients, an anterior systolic epicardial “swing” was evident and was different from the inward endocardial and epicardial motion seen in groups 2 and 3. Septal WM was decreased in group 1 compared with group 2 (2.9 vs. 6.0 mm,P< 0.001), with no significant difference in septal thickening. This was not different from the reduced septal motion seen in group 3 (4.1 mm), which was accompanied by both reduced thickening and abnormalities of anterior WM. Lateral WM was increased in group 1 compared with group 2 (9.9 vs. 8.2,P< 0.001), with no significant difference in lateral wall thickening (34.6% vs. 39%).ConclusionsThere is a characteristic contraction pattern on gated SPECT myocardial perfusion imaging in post-CABG patients distinguished by apparent septal hypokinesis with preservation of septal wall thickening, apparent increase in endocardial lateral WM, and an anterior epicardial “swing,” different from the contraction pattern seen in normal patients and those with previous anterior wall infarction. The related perfusion pattern aids in evaluation of the mechanism of these findings.

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

The authors examined three patients with pure primary mediastinal seminomas, all of whom had marked Ga-67 uptake on scintigraphy. The unusual presentation of sclerotic bone metastases with remarkable extraosseous soft tissue involvement was observed in one patient. Another had a seminoma associated with a multiloculated thymic cyst, which is a rare lesion.

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

摘要:

PurposeMany studies have shown that the S-phase fraction is a reflection of the proliferation potential of tumors, and DNA aneuploidy is more common in malignant tumors. In this preliminary study, the authors assessed the Tc-99m MIBI uptake of brain tumors and its relation to tumor grade and DNA content of the tumor cells.MethodsTen patients (eight male, two female; mean age, 53.2 ± 6.11 years) with untreated brain tumors were included in the study. SPECT imaging was performed 20 minutes after injection of 740 MBq (20 mCi) Tc-99m MIBI. A single detector camera with a low-energy high-resolution collimator was used for image acquisition. A region of interest was drawn in the tumor area under magnetic resonance guidance. A Tc-99m MIBI uptake index was computed as the mean tumor-to-background ratio. Flow cytometric analysis of fresh tumor tissue specimens was performed immediately. The percentages of cells in the G0/G1, S, and G2/M phases were determined for each patient.ResultsDNA aneuploidy was found in 4 (49%) patients, whereas diploidy was found in 6 (60%) patients. There was a significant positive correlation between the Tc-99m MIBI uptake and the percentage of the S-phase fraction of the cell cycle (P= 0.000, r = 0.95). The Tc-99m MIBI index was significantly greater in aneuploid tumors than in diploid tumors (P< 0.01).ConclusionsHigh-grade brain tumors have increased Tc-99m MIBI uptake compared with that of low-grade tumors. Tc-99m MIBI uptake is correlated with the percentage of the S-phase fraction of the cell and the aneuploidy level of the brain tumor. This preliminary report suggests that Tc-99m MIBI imaging may be useful in the evaluation of the biologic characteristics of brain tumors.

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID

ISSN:0363-9762    

出版商:OVID    

年代:2003

数据来源: OVID