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Pinhole magnification scintigraphy is an effective means of evaluating the pediatric skeleton because it provides optimal high-resolution images. This technique is indicated when diagnostic uncertainty persists after high-resolution imaging with parallel hole collimation. Pinhole magnification scintigraphy requires approximately 20 minutes of acquisition time per image and meticulous attention to details such as choice of pinhole insert, collimator positioning, and patient immobilization. However, the technique is superior to planar imaging in demonstrating acute osteomyelitis in bone adjacent to growth centers and epiphyseal involvement that is either primary or the result of local spread of infection. In addition, pinhole imaging has proved highly reliable in the early diagnosis of Legg-Calvé-Perthes disease and is useful in depicting osteonecrosis related to specific causes such as corticosteroid treatment or trauma. Scintigraphic manifestations of femoral head ischemia or infarction and findings indicative of osteomyelitis associated with a hip effusion are well demonstrated with pinhole imaging. This technique also helps characterize osteoid osteomas and may be used intraoperatively to confirm the complete excision of this benign tumor. Finally, pinhole magnification scintigraphy clearly depicts fractures of the femoral neck and allows a high degree of confidence in diagnosing injuries to the small bones of the hands and feet.

Radiographic and bone mineral (BM) data were collected over a three-year period on 195 patients with chronic renal failure. Most women maintained BM on dyalysis, whereas 44% of the men lost BM (p less than 0.05). Following transplantation, 86% of the patients either maintained or restored BM. After parathyroidectomy, only half of the women and 34% of the men gained BM. Normal radiographs may be associated with low BM values, but there is a correlation between decreasing BM and increasing renal osteodystrophy in women (p less than 0.05).

With an Anger camera for scintigraphic recording of bremsstrahlung radiation from phosphorus-32, the distribution of intraperitoneal colloidal chromic phosphate was followed in patients with gynecologic tumors. Sequential pelvic, abdominal, and thoracic scintiphotos over a three-week period revealed rapid and persistent focal aggregation of the radiocolloid with no change in pelvic or peritoneal radionuclide distribution patterns. Visualization of intrathoracic lymph node uptake did not correlate with the presence of diaphragmatic tumor. This study demonstrates the utility of scintigraphy for monitoring the distribution of intraperitoneal beta emitters and the need for developing alternative methods of administering these therapeutic agents to achieve more uniform patterns of distribution.

Transaxial emission computed tomography (ECT) was performed in dogs with experimentally induced abscesses, using 67Ga and several 99mTc-labeled organ-specific radiopharmaceuticals. Superimposition of 99mTc ECT images onto the 67Ga images gave the precise anatomic location of the abnormal foci of 67Ga uptake, correctly localizing a perinephric abscess, a splenic abscess, and a focus of osteomyelitis. This technique also permits further characterization of regions of decreased activity.