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Persistent left superior vena cava (PLSVC) is a development variation of the embryonic thoracic venous system. It can be isolated or associated with congenital heart disease combined with shunting problems. Many image findings of PLSVC have been reported, but few mentioned findings in a first-pass radionuclide angiography. We report a case of PLSVC found incidentally in a first-pass radionuclide angiography with tracer injection through the left jugular vein. The right ventricular ejection fraction was underestimated. Injection via the right jugular or right cubital vein is recommended to obtain accurate ejection fractions in cases of PLSVC without shunting.

Purpose: The complexity of small oral cavity and intimate apposition of the oral cavity mucosal surfaces make CT identification of obvious masses difficult. Puffed-cheek CT improves the evaluation of oral cavity lesions. We used the puffed-cheek maneuver with 18F-FDG PET/CT scans to determine the feasibility and accuracy in clinical practice and to identify any benefits., Patients and Methods: Twenty-two patients with oral cancer were included. They were instructed to perform the puffed-cheek maneuver after a conventional 18F-FDG PET/CT scan. Two physicians reviewed the puffed-cheek and conventional 18F-FDG PET/CT images and achieved consensus about the cancer extent, location, and dental artifacts before classifying and grading the oral cancers. Dichotomous results of localized or extended cancer and artifact grading scores from the puffed-cheek and conventional 18F-FDG PET/CT methods were compared using McNemar test and the Wilcoxon signed-rank test. P < 0.05 was considered significant., Results: The puffed-cheek maneuver with 18F-FDG PET/CT was practical and had incremental benefits. The conventional 18F-FDG PET/CT classified 12 patients correctly as having localized or extended cancer, and the puffed-cheek 18F-FDG PET/CT classified 21 patients correctly. Puffed-cheek 18F-FDG PET/CT found a synchronous skip cancer and provided detailed cancer delineation. This method might reduce the effects of dental artifacts without undesirable muscular FDG uptake., Conclusions: Puffed-cheek PET/CT is feasible in the current clinical setting and can improve the delineation of oral cancer extent and location, with a potential benefit of reducing dental artifacts.

Autosomal dominant polycystic kidney disease is a systemic hereditary disease characterized by renal cysts and sometimes involvement of the liver. We present a 65-year-old woman with autosomal dominant polycystic kidney disease on regularly hemodialysis who recently experienced intermittent right upper quadrant abdominal pain and elevated intact parathyroid hormone for more than a year. She was referred for double-phase Tc-99m sestamibi scintigraphy, under the impression of hyperparathyroidism. Apart form increased uptake in the right thyroid bed, the images showed a large photon-deficient area in the upper portion of the abdomen corresponding to the liver.

Purpose: Pulmonary sclerosing hemangioma (PSH), or the alternative name of "sclerosing pneumocytoma," is a rare benign neoplasm. PSH is often asymptomatic and presents as a solitary pulmonary nodule on radiologic imaging studies. Few articles have been reported to describe the FDG PET findings about PSH. We reported FDG PET findings of 6 cases of PSH and reviewed the literatures., Materials and Methods: FDG PET and PET/CT imaging studies of 6 patients with proven PSH were reviewed. The relation between the degree of FDG uptake and tumor size was analyzed., Results: All 6 tumors were detected by FDG PET or PET/CT. Mean diameter of these tumors was 2.9 cm. Mean standard uptake value was 2.45 (range, 1.8-3.93). The maximal standard uptake value of FDG uptake was positively correlated with the tumor size (R = 0.9694, P < 0.05)., Conclusions: PSH demonstrates low to moderate uptake on FDG PET imaging. The larger PSH has higher uptake and might be misrecognized as a malignancy. The possibility of false-positive result caused by PSH should be considered while interpreting FDG PET images of solitary pulmonary nodules.

A 74-year-old man underwent low anterior resection for rectal cancer. Technetium-99m methylene diphosphonate (MDP) bone scanning was performed as part of the patient's postoperative follow-up study. Scans revealed an area of increased tracer uptake in the left hemipelvis. Coronal single-photon emission computed tomography and caudal images clearly separated the lesion from the skeletal structures. Transverse magnetic resonance images showed a large diverticulum originating from the left lateral wall of the bladder. The pelvic findings on the bone scan were the result of tracer retained within this diverticulum.

Bone scintigraphy plays an important role in the early detection of bone metastases in patients with nasopharyngeal carcinoma and serial scans may aid the clinician to assess the therapeutic response. A superscan is a pattern described as abnormal bone scan, indicating extensive bony metastases associated with various neoplastic diseases. Bone scans from 407 patients with nasopharyngeal carcinoma were reviewed retrospectively. Only six superscans (1.5%) were found. The appearance of a superscan is frequently accompanied by an abnormal titer of serological markers IgG-VCA and IgA-VCA, liver metastases, and poor survival. Although a superscan rarely occurs in nasopharyngeal carcinoma, its appearance may represent a poor prognosis in these patients.

Gastrointestinal vasculitis is a recognized but frequently misdiagnosed complication of systemic lupus erythematosus. The authors investigated the usefulness of three-phase Tc-99m pyrophosphate abdominal scintigraphy for identifying areas of vasculitis in patients with systemic lupus erythematosus who have gastrointestinal symptoms (diarrhea or abdominal pain). Among patients with gastrointestinal symptoms, 62 of 82 (75%) patients showed positive scan results, suggesting gastrointestinal vasculitis. Among patients without gastrointestinal symptoms, 6 of 43 (13%) patients showed positive scan results. Although three-phase Tc-99m pyrophosphate abdominal scintigraphy cannot provide a definite diagnosis of vasculitis of the gastrointestinal tract, it is a noninvasive and convenient method for suggesting and monitoring gastrointestinal vasculitis.

Focal hyperactivity indicative of metastases is a rare finding in bone marrow imaging. In a lung cancer patient with multiple bony metastases, the Tc-99m phytate bone marrow imaging revealed multiple focal areas of increased radioactivity corresponding to the bone scan findings. The findings presented are consistent with a previous animal study, which found that phytate distribution was similar to that of diphosphonate in the skeletal system of rats and rabbits. The authors conclude that Tc-99m phytate should not be used as a bone marrow imaging agent. Further studies of Tc-99m phytate bone marrow scintigraphy on human beings are under way.

In a patient with Pellegrini-Stieda disease, radiographs of the knees were unremarkable at the time the three-phase bone scintigraphy was abnormal. The results of follow-up radiographs three months later remained normal in the left knee, where local steroid injection was given, but revealed typical positive results in the right knee with no treatment. The three-phase bone scintigraphic pattern is rather typical and antedates the radiographic changes. Thus, the radionuclide technique would provide a useful procedure for the early diagnosis and treatment of Pellegrini-Stieda disease.

Sequential liver scintiphotography with Tc-99m pyrophosphate (PYP) was used to prospectively evaluate its uptake patterns in hepatoma. The scintiphotos and time-activity curves of 40 cases were analyzed. Two distinct patterns of tumor activity were noted: gradual but complete extraction and trapping of Tc-99m PYP in hepatoma in 38% of the patients (group 1), and absence of subsequent Tc-99m PYP uptake in hepatoma after initial blood pool activity in 62% of the patients (group 2). Since extraction and trapping of Tc-99m PYP occur approximately in two fifths of the patients with hepatoma, we conclude that Tc-99m PYP liver scintigraphy is not worthwhile supplementing the conventional radionuclide studies for diagnosing hepatoma, even in the selected patients in the countries where the prevalence of hepatoma is high.