Serafin Tiu

Radioimmunodetection of non‐small cell lung cancer using technetium‐99m‐anticarcinoembryonic antigen immu‐4 fab′ fragment

Background. Although computed tomography and magnetic resonance imaging have improved the staging and evaluation of non‐small cell lung cancer (NSCLC), mediastinal staging lacks adequate specificity and sensitivity. Radioimmunodetection may augment computed tomography and magnetic resonance imaging. The authors evaluated the ability of the technetium 99m‐anticarcino‐embryonic antigen IMMU‐4 Fab′ fragment to localize NSCLC in vivo, measured its pharmacokinetics, and estimated its radiation dose.

Aortic aneurysm dissection causing V/Q mismatch

A case of unilateral mismatch on a ventilation/perfusion lung scan due to aortic aneurysm dissection is presented. Pulmonary embolism should not be considered the sole cause of unilateral lung mismatch. Clinical evaluation and pulmonary angiography should be used for a definitive diagnosis.

Reversal of drug-induced rhabdomyolysis on bone scan.

A 75-year-old man with prostate cancer was referred for metastatic workup. A Tc-99m methylene diphosphonate bone scan was performed which revealed diffusely increased radiopharmaceutical uptake in the muscles of the arms and thighs. The patient was taking simvastatin 80 mg per day and gemfibrozil 600 mg twice a day for high cholesterol. The patient reported myalgias, and laboratory evaluation was consistent with rhabdomyolysis. After discontinuation of the anticholesterol medications, the clinical and laboratory evaluations normalized. Bone scan performed 1 year later demonstrated complete resolution of muscle uptake.

Breakdancer's pulmonary embolism

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

Discordance between chest X-ray and gallium scan

A 50-year-old white homosexual male had a previous history of Legionnaires disease in 1978, viral hepatitis in 1981, cytomegalovirus disease in August 1982. He was admitted for several weeks of fever, cough, malaise, and headache. PE and blood exams were unremarkable. Chest x-ray revealed clear lung fields (Fig 1). A gallium scan (Fig 2) was obtained that showed diffuse lung uptake, especially in the left posterior area. Transbronchial biopsy was done and revealed positive Pneumocystis carinii. Therapy with trimethoprim and sulfamethoxazole was started. Subsequent chest radiographs were normal until 17 days later when the left lung base began to

Detection of lacrimal gland infiltration on routine bone scintigraphy.

We report a bone scan finding of bilaterally and symmetrically increased uptake at the lateral orbital rims in a patient with disseminated Hodgkins disease. Computerized axial tomography (CT) demonstrated lacrimal gland enlargement, presumably due to infiltration by Hodgkins disease. Both the radionuclide bone scan and CT findings, as well as the other physical and radiographic manifestations of Hodgkins disease, resolved after chemotherapy. Infiltration by Hodgkins lymphoma is a rare cause of lacrimal gland enlargement. We believe that this pattern of uptake on a routine bone scan should alert the physician to possible lacrimal gland disease, which could then be more definitively evaluated by CT examination.

Focal pulmonary edema correlation with perfusion lung scan

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.

Radioxenon retention in the skeleton on a routine ventilation study.

Marked retention of radioxenon by the skeletal structures during a routine ventilation scan is described. Xenon uptake by bones occurs largely in the intraosseous fat. Augmented uptake in this case may be related to the patients prolonged steroid therapy.