A comparative study between planar Ga-67, Tl-201 images, chest x-ray, and x-ray CT in inoperable non-small cell carcinoma of the lung.

Seventy patients with newly diagnosed, pathologically proven inoperable non-small cell lung cancer (NSCLC) had planar Ga-67, Tl-201, chest x-ray, and chest CT imaging performed. Tumor/Normal tissue background (T/B) ratio was calculated for 62 Ga-67 and 55 Tl-201 scintigraphy studies and comparisons were made between Ga-67 and Tl-201 imaging results regarding T/B ratios, site of lesion, and histologic type. The impact of the images on the initial knowledge of the extent of the tumor and on the radiotherapy (RT) planning was evaluated for each patient. For primary lesions, Ga-67 imaging results were positive in 94% (66 of 70 patients) versus 71% (50 of 70 patients) for Tl-201 scans (P < 0.005) and the T/B ratio was > 1.5 in 74% (46 of 62 patients) for Ga-67 versus 36% (20 of 55 patients) for Tl-201 (P < 0.0001). For centrally located lesions, sensitivity for Ga-67 was 100% (53 of 53 patients) versus 74% (39 of 53 patients) for Tl-201 (P < 0.0005) and the T/B ratio > 1.5 in 84% (38 of 45 patients) for Ga-67 versus 38% (15 of 40 patients) for Tl-201 (P > 0.001). For peripheral lesions, sensitivity of Ga-67 was 76% (13 of 17 patients) versus 64% (11 of 17) for Tl-201 (P > 0.05) and the T/B ratio was > 1.5 in 47% (8 of 17 patients) for Ga-67 versus 33% (5 of 15 patients) for Tl-201 (P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral perfusion changes in schizophrenic patients using Tc-99m hexamethylpropylene amineoxime (HMPAO).

Tc-99m hexamethylpropylene amineoxime (HMPAO) was used to image cerebral perfusion changes in 20 patients with chronic schizophrenia (19 male and 1 female, aged 22-48, at an average age of 29.0). All were being given neuroleptic drugs. Twelve had electroconvulsive therapy. In addition, all had abnormal studies except one, who was normal and had a poor response to treatment. Ventricular dilatation and cerebral atrophy was seen in eleven patients, and 77 focal lesions were detected. Forty-two lesions demonstrated increased HMPAO retention, which was distributed as follows: 26 in the basal ganglia in 14 patients (12 bilateral, 2 unilateral); 10 along the sylvian fissure in the parietotemporal region; and 3 in the frontal and 1 in each of the temporal, parietal, and occipital regions. Thirty-five focal lesions exhibited decreased perfusion: ten parietal, eight frontal, seven temporal, six cerebellar, and four occipital lobes. This study demonstrates the potential value of Tc-99m HMPAO in schizophrenia and other psychiatric disorders.

Technetium-99m HM-PAO images (planar and SPECT) of the human brain.

Tc-99m HM-PAO has a great potential in the assessment of regional brain perfusion in various neurologic disorders. An atlas of planar and SPECT images of the normal and abnormal human brain has been generated using Tc-99m HM-PAO as the tracer.

Gallium-67 scintigraphy in acute pancreatitis.

Acute pancreatitis is a serious surgical problem with a high incidence of mortality. Both ultrasound and X-ray CT have problems in identifying the extent and severity of the disease and the response to therapy. 67Ga-citrate has been used in 21 patients with clinically diagnosed acute pancreatitis: 9 patients had X-ray CT and 15 had US examination. Gallium scans were more sensitive than X-ray CT and US in detecting the extent and severity of acute pancreatitis. In addition, gallium was helpful to monitor the response to therapy when the scan was repeated at various intervals in three patients. A subtraction technique using 99mTc-tin colloid and 67Ga-citrate was helpful to mask the liver uptake of gallium and clearly identify the extent of acute pancreatitis.

99mTc-DTPA uptake in malignant and inflammatory bowel disease: experience from gastrointestinal bleeding studies.

During the evaluation of 99Tcm-DTPA for localization of acute gastrointestinal bleeding in 81 studies (78 patients), it was observed that there was an increased 99Tcm-DTPA at sites of inflammatory and malignant lesions of the GI tract in 18 studies. Active bleeding was detected only in 10 and no bleeding was detected in the remaining eight studies. In all the increased DTPA uptake helped to localize the site of bleeding. Image subtraction of early from delayed images according to a predefined acquisition and processing protocol helped to differentiate bleeding from non bleeding lesions. We conclude that increased 99Tcm-DTPA uptake in malignant and inflammatory lesions of the bowel is an additional advantage for its use in localizing the site of acute GI bleeding. Technetium-99m diethylenetriamine pentaacetic acid (99Tcm-DTPA) has been widely used for imaging the brain and kidneys since it was introduced by Hauser in 1970. Kadir and Strauss in 1979 reported that 99Tcm-DTPA localizes in segments of bowel with inflammation due to ulcerative colitis, regional enteritis and other forms of enterocolitis. Recently we reported the advantages of 99Tcm-DTPA in localizing the site of acute gastrointestinal bleeding. Inflammatory bowel diseases are among the causes of gastrointestinal bleeding. One of the problems in localizing the site of the bleeding by radionuclide procedures is the intermittent nature of the bleeding. We have reviewed all gastrointestinal bleeding studies in our department using 99Tcm-DTPA from January 1984 till September 1985 in order to find out whether increased uptake of 99Tcm-DTPA was helpful in localizing the bleeding lesion due to malignancy and/or inflammation.

Lymphscintigraphy in peripheral lymphedema using technetium-labelled human serum albumin: normal and abnormal patterns.

Lymphscintigraphy using Tc-99m human serum albumin (HSA) was examined in 23 patients with peripheral leg lymphedema. Each was injected intradermally with one mCi in the medial web space bilaterally. Images of the lower pelvis and both thighs were obtained within five minutes after injection using an extralarge field view camera GE 500A with low energy all purpose collimator interfaced with G.E. Star computer. These images were acquired in dynamic byte mode, 128 X 128 matrix size, every minute for 40 minutes. Delayed images for this region and of both legs were also taken at 90 minutes and time activity curves from comparable regions of interest over the inguinal area bilaterally were generated. Three patterns emerged: 1--normal lymph flow (12 patients) characterized by symmetrical or nearly symmetrical early appearance of lymphatics (medial bands) with visualization of inguinal and pelvic lymph nodes in both early and delayed images. Time activity curves showed step ladder rise, in "pulses" every three to four minutes. 2--enhanced lymph flow pattern (6 patients) was characterized by rapid movement of radiolabelled albumin through dilated lymphatics, occasionally with subcutaneous pooling, and both larger and more numerous inguinal and pelvic nodes on the lymphedematous side. 3--obstructed lymph flow (5 patients) was characterized by subcutaneous pooling, absent lymphatics, (medial bands) and flat, time activity curve on the lymphedematous side (only background activity) and absent inguinal and pelvic nodes. On delayed images, where lymphatic obstruction was incomplete there was delayed appearance of inguinal pelvic nodes which were fewer and smaller compared to the nonedematous side.(ABSTRACT TRUNCATED AT 250 WORDS)