Gang-Uei Hung

Unilateral ventilation--perfusion mismatch on pulmonary scintigraphy caused by anomalous origin of a pulmonary artery from the innominate artery.

A ventilation–perfusion mismatch on pulmonary scintigraphy is usually secondary to a pulmonary vascular problem, such as thromboembolism, tumor compression, or congenital artery defects or to shunt procedures performed to treat congenital heart disease. The authors present a rare case of anomalous origin of the left pulmonary artery from the innominate artery, left pulmonary hypoplasia, and a right aortic arch. A Tc-99m MAA perfusion scan revealed unilateral absence of pulmonary perfusion. In the Xe-133 ventilation study, both lungs were visualized.

Rapid resolution of hypertrophic pulmonary osteoarthropathy after resection of a lung mass caused by xanthogranulomatous inflammation.

A 36-year-old woman had hypertrophic pulmonary osteoarthropathy (HPOA) caused by xanthogranulomatous inflammation of the lung. After resection of the lesion, bone pain disappeared dramatically. A bone scan repeated 2 months later revealed resolution of HPOA. This condition is most frequently a result of lung cancer, which occurs in 80% of patients with HPOA. To our knowledge, HPOA in association with xanthogranulomatous inflammation has not been reported before.

Focal Cerebral Hyper-Perfusion in Phantom Limbs: Assessed by TC-99M HMPAO SPECT

Phantom limb pain is a common experience for patients who have received amputation. However, the definite mechanism is still not clear. Here, we describe a patient who suffered from phantom limb pain after left above-elbow amputation. The Tc-99m hexamethylpropylene amine oxime (HMPAO) brain single photon emission computed tomography (SPECT) study revealed increased regional cerebral blood flow in the right parietal cortex. This finding may imply the involvement of cerebral cortex in the development of phantom limb pain. Further study is worthwhile to elucidate the utility of SPECT and the role of cortex in phantom limb pain.

Two incorrect FDG positron emission tomographic interpretations of a pulmonary mass and mediastinal lymphadenopathy

A pulmonary mass located in the right lower lung field with mediastinal lymphadenopathy was found incidentally in a 50-year-old woman. She underwent whole-body F-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) for further diagnosis. The mediastinal lymphadenopathy showed intense tracer uptake (standard uptake value [SUV], >2.5), but it was proved to be a benign process (anthracosis) on pathologic examination. However, a mass in the right lower lung showed low FDG uptake (SUV, 1.69), but it was found to be an adenocarcinoma.

Recurrent hyperfunctioning parathyroid gland demonstrated on radionuclide imaging and an intraoperative gamma probe.

Radionuclide imaging with Tc-99m MIBI is the preferred mode of parathyroid localization in current practice. It also successfully identifies hyperfunctioning autotransplanted parathyroid tissue. The authors report a case with recurrent hyperparathyroidism after total parathyroidectomy and autotransplantation in the forearm. Double-phase Tc-99m MIBI imaging successfully localized the hyperfunctioning parathyroid tissue, which was missed by magnetic resonance imaging and ultrasonography. In addition, the parathyroid tissue was localized using an intraoperative probe at subsequent surgery.

Colon Necrosis Demonstrated on 99mTc-Pyrophosphate Scintigraphy

A 59-year-old female with rectal cancer underwent low anterior resection with colostomy. Two days after operation, ischemic change of colon was suspected. 99mTcpyrophosphate scintigraphy demonstrated an area of increased radioactivity at the left lower abdomen and colon necrosis was diagnosed. At operation, left hemicolectomy was performed and confirmed the diagnosis of necrosis of descending colon.

Papillary thyroid carcinoma with angioinvasion of the great vessels shown on an I-131 whole-body scan.

The authors describe a rare case of metastatic papillary thyroid carcinoma with direct invasion of the superior vena cava and bilateral subclavian veins shown on an 1-131 whole-body scan.

Incidental visualization of an esophageal prosthesis on Tc-99m DISIDA cholescintigraphy.

A 70-year-old man with gallstones and epigastric pain underwent Tc-99m DISIDA cholescintigraphy to investigate acute cholecystitis. There was no visualization of the gallbladder during the 4-hour study. In addition, significant tracer accumulation in the medial portion of the chest and the proximal bowel were noted. A review of his medical history showed that he had esophageal cancer and a radical esophagectomy and reconstruction with a gastric tube.