Visualization of a recurrent carcinoid tumor and an occult distant metastasis by technetium-99m-sestamibi.

We present a case of atypical carcinoid that showed avid uptake of sestamib in a recurrent bronchial carcinoid tumor and a solitary, unsuspected, occult, bony metastatic lesion in the distal femur. As carcinoid tumors are known to be vascular, we suspect that its avidity for sestamibi is secondary to increased blood flow, although other factors such as the transmembrane potentials of plasma and mitochondrial membranes and relative number of mitochondria present in the cells of this carcinoid tumor, may have also played a role.

The unsuspected complications of bacterial endocarditis imaged by gallium-67 scanning.

In this case report, we present a patient with bacterial endocarditis who was evaluated by 67Ga imaging for persistent fever despite treatment with multiple intravenous antibiotics. Although evidence of bacterial endocarditis was absent with 67Ga imaging, the study demonstrated findings that represent complications of bacterial endocarditis. The procedure demonstrated moderate pericardial uptake of isotope and thus provided the first evidence of pericarditis which was later confirmed at surgery. The study also demonstrated mildly increased activity in the vicinity of the aortic root and right atrium. A sinus of valsalva abscess, complicating the underlying diagnosis of bacterial endocarditis, was found and treated with surgery and antibiotics. At autopsy 4 wk later, a persistence sinus of valsalva abscess was found which extended into the right atrium.

Evaluation of postoperative osteomyelitis of the sternum comparing CT and dual Tc-99m MDP bone and In-111 WBC SPECT.

This article reports on a retrospective study of 32 patients who underwent CT and combined Tc-99m MDP and in-111 WBC SPECT between 1988 and 1991 for post-operative sternal osteomyelitis. Of these 32 patients, 7 patients (Group 1) underwent evaluation for possible sternal osteomyelitis due to persistent fevers, leukocytosis, or changes in the sternal incision; 12 patients (Group 2) had surgically proven osteomyelitis, and in 13 patients (Group 3) there was definite clinical evidence of sternal wound infection (however, surgical specimens of the sternum were not submitted). There was considerable overlap between the CT findings in the soft tissues adjacent to the sternum in Group 1 and Group 2 patients. Severe demineralization was seen in two patients, and erosion of the sternum was seen in five patients with proven osteomyelitis. Combined Tc-99m MDP bone and in-111 WBC SPECT was positive for osteomyelitis in 11 of 12 patients in Group 2. One patient with osteomyelitis had negative scintigraphy; however, this patient had a four-week course of IV antibiotic therapy prior to the study. All seven patients in Group 1 had negative SPECT scans and were treated successfully with oral antibiotics and minimal soft tissue debridement. Three patients in Group 3 had negative SPECT scans and were treated successfully with antibiotics and limited debridement. Ten patients with positive SPECT scans were treated with a combination of antibiotics and aggressive surgical intervention. In conclusion, CT findings in the soft tissues offer little specificity in distinguishing soft tissue inflammation from osteomyelitis of the sternum.(ABSTRACT TRUNCATED AT 250 WORDS)

Necrotizing tracheobronchitis identified on an indium-111-white blood cell scan.

The clinical entity of necrotizing tracheobronchitis (NTB) is well described in the pediatric literature. The incidence of NTB in neonatal autopsies varies from 4% to 44%. More than 3 hr of assisted ventilation may be necessary for the development of NTB in neonates. A similar clinical problem was described as "hemorrhagic tracheitis" in two adults during high frequency jet ventilation and as a complication of conventional mechanical ventilation in an adult. We present here a rather unusual case of NTB in an adult on mechanical ventilation, in whom tracheobronchitis was diagnosed incidentally with an 111In white blood cell scan obtained for other purposes.

Cardiac aneurysm complicated by E. coli abscess.

An E. coli myocardial abscess developed in the region of an old aneurysmal myocardial scar. In spite of vigorous antibiotic therapy fever and positive blood cultures persisted. A combination of In-111 WBC scanning and Tc-99m RBC gated heart imaging located the infection in the aneurysmal scar. The abscess was resected and the patient survived.

Cardiac blood pool imaging: a review.

The field of cardiac blood pool imaging has been reviewed. The radioisotopes and radiopharmaceuticals used for this purpose have been discussed. Data related to the radiation exposure from these agents were presented and compared with the radiation exposure of a conventional contrast angiogram. Application of cardiac blood pool imaging to the qualitative evaluation of pericardial effusions, cogenital heart disease, acquired heart disease, and cardiac shunts have been discussed. Quantitative methods for measuring cardiac output, stroke volume, left ventricle ejection fraction, left ventricle end-diastolic volume, percent mitral valve regurgitation, and Qp:Qs flow ratios in both right-to-left and left-to-right shunts were presented in detail. Where possible, correlation with contrast angiographic findings was given. Newly developed techniques of ECG gating of cardiac images were also described in detail. This description has included applications of these techniques for evaluation of regions of myocardial dyskinesis and to quantitation of left ventricle diastolic volume, ejection fraction, time between ejection onset and peak systolic flow, ejection duration, and peak circumferential fiber shortening. Once again, these were correlated with contrast angiography where possible. It is concluded that cardiac blood pool imaging is a useful procedure capable of yielding good qualitative and quantitative results in a wide variety of clinical cardiac diseases and that these results compare favorably with those obtained by contrast angiography. Although there are limitations in the present techniques, solutions to at least some of these limitations are possible. Because of its simplicity, safety, and low cost relative to cardiac catheterization, more widespread use of these procedures is urged.

A new approach to the smoothing of dynamic nuclear medicine data: concise communication.

A weighted three-dimensional digital filter that smooths data in both space and time has been developed for use with dynamic nuclear medicine studies. This smoothing algorithm allows a large improvement in signal-to-noise ratio without unacceptable degradation of spatial and temporal resolution. The initial results of using this smoothing algorithm suggests that it is superior to a standard nine-point smoothing function used on dynamic data. This is particularly encouraging since the parameters of the digital filter have not been optimized. The quality of the processed digital images is at least equivalent to that of analog images, and the digital images may be of more diagnostic value. The new algorithm also appears useful in preparing dynamic dynamic data for other manipulations such as the creation of parametric images or the extraction of quantitative measurements.