Faculty Bibliography

A case of pulmonary embolism caused by breakdancing is reported. There was no clinical suspicion of pulmonary embolism

An adult patient with undiagnosed osteogenesis imperfecta presented with a history of multiple fractures. Radiographs could not definitively diagnose the underlying abnormality. The radionuclide bone image suggested the presence of a skeletal dysplasia, and prompted the histopathologic review of fracture fragments. The scan appearance of osteogenesis imperfecta in the adult and possible underlying mechanisms for the radiopharmaceutical distribution are discussed

A case of Waldenstrom macroglobulinemia, a rare cause of diffusely increased skeletal uptake and relatively diminished renal uptake of bone seeking radiopharmaceutical, is presented. This pattern has been described in a variety of disorders. An important observation to be made in these cases is the skeletal distribution of the radiopharmaceutical. In diffuse bone metastases from carcinoma, which is the most common cause of these findings, the increased activity is primarily in the axial skeleton. In some of the more uncommon causes, including certain hematologic disorders, however, the increased skeletal uptake is more homogeneous in distribution, with prominent uptake in the skull and distal extremities

To better define the group of patients at high risk of myocardial infarction (MI) and death associated with lower extremity revascularization procedures, resting gated blood pool studies were obtained in 100 such patients before surgery and results were correlated with the prevalence of perioperative MI. The results indicated that three patient groups could be distinguished on the basis of cardiac ejection fraction. Group I (n = 50) had preoperative ejection fractions ranging from 56% to 83%. None of the patients in group I suffered an acute perioperative MI. Group II (n = 42) comprised patients with ejection fractions ranging from 36% to 55%. There was a 19.0% prevalence of MI in group II, with one cardiac death. Group III included eight patients with ejection fractions ranging from 26% to 35%. There was a 75% prevalence of perioperative MI in these patients, with one cardiac death. All perioperative MIs occurred within the first 48 hr after surgery. Statistical analysis demonstrated a significantly higher prevalence of perioperative MI in patients with gated pool ejection fractions of 35% or less compared with the prevalence in patients with one or more of the other widely used clinical signs of increased cardiac operative risk (p less than .02)

Pulmonary embolism is diagnosed by a mismatched perfusion-ventilation lung scan. The probability is increased further when there is an associated 'hot spot' in the perfusion study caused by focal pulmonary edema

In order to test the possible cardiac-sparing effect of doxorubicin administered by six-hour intravenous infusion and to prospectively evaluate the role of resting left ventricular ejection fraction in monitoring these patients, 33 women with advanced breast cancer were treated with combination chemotherapy containing 5-fluorouracil, cyclophosphamide, and doxorubicin. Doxorubicin was administered via a femoral catheter as a six-hour infusion. Cardiac function was monitored prior to therapy and at intervals during therapy by history and physical examination and by measurement of resting left ventricular ejection fraction with gated pool radionuclide angiography. Twenty-six responses were observed (complete response, seven [21 percent]; partial response, 19 [57 percent]). Systemic toxicity included alopecia, myelosuppression, and nausea and vomiting. There was a progressive fall in resting left ventricular ejection fraction during treatment from a median baseline value of 0.63. Mean fall from baseline left ventricular ejection fraction at a cumulative doxorubicin dose of 200 to 300 mg/m2 was 0.06 (p less than 0.005); at 301 to 449 mg/m2 it was 0.09 (p less than 0.0005); and at 450 mg/m2 or greater it was 0.15 (p less than 0.0005). Clinical congestive heart failure developed in three patients. Even though the decrease in left ventricular ejection fraction was often within the 'normal range' (left ventricular ejection fraction 0.50 or greater), these changes were progressive and appeared to be part of a continuum of doxorubicin-induced myocardial damage. Steady-state infusion levels of doxorubicin in plasma ranged from 90 to 120 nM. They confirm the hypothesis that lower concentrations can be achieved by continuous infusion rather than by bolus infusion. In this study, however, administration of doxorubicin by six-hour infusion did not appear to have a major cardiac-sparing effect. Studies of anthracycline cardiac toxicity should include determination of baseline left ventricular ejection fraction and serial observations during therapy. Failure to include deteriorations in function above an arbitrary cutoff point or to make observations only at higher cumulative doses may underestimate drug-induced myocardial damage

The sequence of scintigraphic patterns in resolving lymphedema in the replanted hind limb of the rat is reported. Compared to simple observation of the limb, scintigraphy using 99mTc-antimony trisulfide colloid (99mTc SbSC) provides multiple qualitative parameters for assessing lymphedema, ie, diffuse uptake in the implanted limb, focal uptake at the site of surgical repair, accumulation in the popliteal node, and activity in the liver. Quantitative analysis in this model was not helpful. Scintigraphic criteria may be utilized to study the effect of alteration in the animal model described. It is hoped that this model can be used to clarify the clinical factors influencing the resolution of lymphedema