Tommy J. Brown

Scintigraphic findings in a primary cerebral amyloidoma.

Bone, brain, and gallium scintigrams are presented of a 48-year-old man with biopsy-proven cerebral amyloidosis. Brain scintigraphy revealed a wellcircumscribed accumulation of Tc-99m pertechnetate in the amyloidoma. Bone scintigraphy using Tc-99m methylenediphosphonate likewise exhibited increased activity in the same area. Gallium-67 citrate, however, failed to localize within the amyloidoma.

Ruptured abdominal aortic aneurysm identified incidental to bone scintigraphy

A report is presented of a man who had a ruptured abdominal aortic aneurysm identified incidental to bone scintigraphy. The bone scan revealed displacement of the left kidney to nearly a horizontal axis and indicated the need for more definitive evaluation. Renal scintigraphy and computed tomography correctly demonstrated a ruptured, but contained abdominal aortic aneurysm.

Angiographic and scintigraphic findings in fibrosing mediastinitis.

The clinical and morphologic findings in the case of a 47-year-old man with fibrosing mediastinitis, most probably due to histoplasmosis, are described. Radionuclide angiography demonstrated obstruction of the superior vena cava with collateral vascularization. Computed tomography demonstrated a large calcific mass interposed between the pulmonary artery and superior vena cava suggesting potential pulmonary vasculature involvement. For this reason, pulmonary scintigraphy was performed which showed right lung perfusion and ventilation defects. Radionuclide angiography and pulmonary scintigraphy complement each other in determining the extent of vascular involvement with fibrosing mediastinitis. However, contrast venography is necessary to correctly delineate the anatomy of the obstructed superior vena cava and its collaterals.

Ga-67 positivity in sarcoidosis of the skin with coincident thyroid uptake of uncertain etiology.

Gallium-67 citrate scintigraphy of a 26-year-old woman with systemic sarcoidosis demonstrated abnormal radiotracer uptake within multiple biopsy-proven sarcoidal cutaneous lesions and within both lobes of the thyroid gland. The etiology of the thyroidal uptake of the Ga-67 was uncertain but it may represent sarcoidal involvement of the gland.

Cholelithiasis demonstrated on hepatobiliary scintigraphy as a photopenic defect within the inferior portion of the liver

A 47-year-old man presented with the clinical findings of acute cholecystitis. During hepatobiliary scintigraphy using Tc-99m DISIDA, a persistent photopenic defect was noted within the inferior portion of the liver in the region of the gallbladder. Abdominal ultrasonography revealed large gallstones with acoustic shadowing within a normal-sized gallbladder. Eleven large gallstones were found within a normal-sized intrahepatic gallbladder at surgery.

Unexpected reversal of gallium-67 citrate avidity in an anaerobic hepatic abscess

A case of anaerobic hepatic abscess (Bacteroides fragilis), which initially was imaged as a cold defect on Ga-67 citrate scintigraphy and, following percutaneous drainage, became Ga avid, is presented. Proposed mechanisms for this occurrence are given.

Evaluation of platelet kinetics in 47 dogs using indium-111

Abstract This report provides data on platelet survival times obtained from 47 dogs over a period of 18 months. Platelets were labeled with indium-111 oxine using isotonic saline as the labeling medium. Results obtained from four different mathematical models are summarized. The mean platelet survival time for 47 animals using the multihit model for calculations was 78.8 ± 2.0 (SEM) hr. Basic statistics are provided on sufficient animals to allow evaluation of the reproducibility of the technique when used on a routine basis.

The complementary roles of brain scintigraphy and computed tomography in multiple sclerosis.

Cerebral computed tomography, with and without iodinated contrast, revealed the appearance and evolution of lesions in a 32–year–old man with multiple sclerosis. Two areas were enhanced with contrast, with one showing a mild mass effect and rim of enhancement. Serial brain scintigraphy using technetium–99m glucoheptonate, following the computed tomography, showed the appearance and regression of corresponding regions of increased uptake. Computed tomography one day prior to brain scintigraphy failed to demonstrate a region of increased accumulation of radiotracer. One week later, however, evidence of a corresponding unenhanced defect was noted on computed tomography. Clinical correlation is given additionally.

Positive Gallium-67 Scintigraphy Associated with Pulmonary Embolism

A 54-year-old man presenting with symptoms and signs of pulmonary embolism demonstrated gallium-67 accumulation within the right lower lung field in the region of a pulmonary embolism with effusion. An associated infectious process was ruled out. This is contrary to the usual clinical experience and identifies a potential pitfall in the use of gallium-67 as an aid in the differential diagnosis of pulmonary embolism and pneumonitis.

Myositis ossificans with Ga-67 citrate positivity.

A 16 year-old boy presented with a firm mass within the left thigh. Ga-6 7 citrate and bone scintigraphy revealed soft tissue radiotracer accumulation within the mass lesion. Radiographs and xerography of the left thigh revealed calcification within the soft tissue mass typical of myositis ossificans. The patients clinical course was uneventful.