Another "great mimicker": FDG-PET/CT imaging findings of sarcoid-like reaction.

Sarcoid-like reaction (SLR) is a cause of non-caseating granulomas in some of the cancer patients with otherwise no signs or symptoms of sarcoidosis. SLR has been described in a variety of solid organ malignancies, including breast and lung cancer. SLR may result in hypermetabolic activity in 18-fludeoxyglucose positron emission tomography (PET)/CT scan, resulting in false positive reporting for malignancy. The purpose of this case series is to expose residents/practising physicians who interpret PET/CT to a series of cases illustrating findings of SLR.

Two-point, timesaving method for measurement of gastric emptying with diagnostic accuracy comparable to that of the conventional method.

Solid-phase gastric emptying is linear. Therefore, the authors calculated gastric-emptying half-time, the time for half of the ingested solids or liquids to leave the stomach, with the conventional multiple-point method and the proposed two-point method (at 0 and 120 minutes) in retrospective and prospective studies of 50 patients each. The results showed excellent correlation. Results with the two-point method were comparable to those with the multiple-point method, and the two-point method substantially reduced technologist and camera times.

Intraoperative probes.

OBJECTIVE: Design features of intraoperative probes are presented. A brief discussion of the sentinel node concept and relevant radiopharmaceuticals is given. The importance of the injection technique and the necessity of imaging in radiotracer techniques for sentinel node detection are explained. Probe calibration, procedural precautions, intraoperative techniques, and radiation dosimetry relevant to the successful use of intraoperative probes are discussed. Intraoperative use of gamma probes requires a team effort involving surgery and nuclear medicine personnel and requires that team members understand the fundamentals of probe use. After reading this paper, the nuclear medicine technologist will be able to: (a) describe present day and future potential use of intraoperative probes; (b) define the sentinel lymph node (SLN) concept; (c) state the radiopharmaceuticals and injection techniques used for SLN evaluation; (d) name several SLN detection procedures; and (e) discuss the design features and care of currently available probes.

Lymphoscintigraphic identification of sentinel lymph nodes: clinical evaluation of 0.22-micron filtration of Tc-99m sulfur colloid.

PURPOSE: To evaluate the use of 0.22-micron filtration of technetium-99m sulfur colloid particles in the optimization of lymphoscintigraphy. MATERIALS AND METHODS: Forty-one consecutive lymphoscintigraphic studies obtained with 0.22-micron filtration of Tc-99m sulfur colloid in 41 patients (26 men, 15 women; average age, 55.4 years) and 41 consecutive studies obtained with 5.0-micron filtration in 41 patients (20 men, 21 women; average age, 54.5 years) were retrospectively, randomly reviewed. Studies were evaluated for lymphatic channel depiction and sentinel lymph node depiction. Studies included immediate flow images (obtained at 10 seconds per frame) and multiview static images obtained up to 2 hours after intradermal Tc-99m sulfur colloid injection. RESULTS: The number of drainage beds visualized was 52 with 5.0-micron filtration and 51 with 0.22-micron filtration (P = .570). The number of lymphatic channels visualized was 45 with 5.0-micron filtration and 75 with 0.22-micron filtration (P = .006). The number of lymph nodes visualized was 102 with 5.0-micron filtration and 123 with 0.22-micron filtration (P = .123). The number of studies judged as optimal (i.e., depicted lymphatic channels leading to sentinel nodes) was 10 with 5.0-micron filtration and 19 with 0.22-micron filtration (P = .038). The number of studies with depicted lymph nodes but no depicted lymphatic channel was 15 with 5.0-micron filtration and six with 0.22-micron filtration (P = .023). CONCLUSION: The use of 0.22-micron filtration in the preparation of Tc-99m sulfur colloid substantially improves study quality and increases the diagnostic certainty in the identification of sentinel lymph nodes.

In-111 labeled octreotide imaging of a primary carcinoid lesion undetected by conventional imaging studies in a patient with "chronic pancreatitis".

This is a case report of a patient with an initial diagnosis of chronic pancreatitis who actually had metastatic carcinoid tumor. His symptoms of abdominal pain, weight loss, and diarrhea were manifestations of the large tumor bulk within the liver as well as carcinoid syndrome. Although abdominal CT scans showed multiple liver lesions, the primary lesion was not identified by conventional imaging studies. However, the mid-gut primary lesion was visualized on in-111 labeled octreotide scintigraphy; where the liver lesions were better delineated and seen to be separate from the normal pancreas when the Tc-99m sulfur colloid images were compared to the octreotide images.

Tc-99m DTPA and I-131 hippurate renography. Findings in hepatorenal syndrome.

Tc-99m DTPA and I-131 OIH renography were performed simultaneously in a patient with hepatorenal syndrome. Blood flow was delayed and diminished bilaterally; there was Tc-99m DTPA and I-131 OIH retention in the parenchyma with no evidence of tracer retention in the collecting systems. The I-131 OIH renogram curve demonstrated a steadily rising pattern, whereas the Tc-99m DTPA curve demonstrated an initial vascular peak and was subsequently flat. There was no appreciable response to furosemide. These findings are not specific for hepatorenal syndrome, and the diagnosis is based on the characteristic clinical setting and the exclusion of other causes of renal failure. A brief literature review and a discussion of differential diagnosis are included.

The use of technetium-99m pertechnetate in postoperative thyroid carcinoma. A comparative study with iodine-131.

Over 3 years, a prospective comparison was made between Tc-99m pertechnetate and I-131 for the detection of residual and metastatic tissue in the follow-up of patients with cancer of the thyroid. All patients stopped thyroid medication for a minimum of 4 weeks. All patients had imaging done first with Tc-99m pertechnetate followed within a maximum of 2 weeks by I-131. The study included 66 patients in whom 81 studies were done with both Tc-99m and I-131. The results showed that 27 studies were positive with both Tc-99m and I-131 (true positive): 19 in the thyroid bed, four lymph nodes, two bony metastases, and two pulmonary metastases. Five patients had negative results with Tc-99m and positive results with I-131 (false negative): three in the thyroid bed, one lymph node metastasis, and one pulmonary metastasis. Only one case was positive with Tc-99m in the neck but negative with I-131 (false positive). The remaining 48 studies were negative both with Tc-99m and I-131 (true negative). Considering I-131 imaging as the standard procedure, Tc-99m had a sensitivity of 87%, specificity of 97%, and accuracy of 92.5% for the detection of residual or metastatic functioning thyroid tissue.

Congenital absence of the mammary gland.

Tc-99m pertechnetate is known for its uptake and excretion by the mammary gland. Generally, lactating women are not advised to have any radioisotopic studies. If it is necessary to have one, it is recommended that they do not breast-feed their children for at least 24 hours. Congenital absence of the mammary gland is a rare condition. This case was accidently discovered. Nuclear medicine physicians should be aware of the value of clinical examination of patients, and that not every absent or asymmetric breast shadow is due to surgical resection.