Kenichi Nagasawa

Pulmonary vein and left atrial invasion by lung cancer: assessment by breath-hold gadolinium-enhanced three-dimensional MR angiography.

Purpose The purpose of this work was to evaluate the ability of breath-hold gadolinium-enhanced three-dimensional (3D) MR angiography to assess the invasion of the pulmonary vein and the left atrium by lung cancer. Method Gadolinium-enhanced 3D MR angiography was performed in 20 consecutive patients with lung cancer. Results At two sites with left atrial invasion shown by MR angiography, associated partial resection of the left atrium was performed. At five sites with invasion of the proximal pulmonary vein within 1.5 cm from the left atrium on MR, partial resection of the left atrium was performed at one site, and the pulmonary vein was resected at the intrapericardial portion at three sites. At two sites with invasion of the proximal pulmonary vein 1.5 cm more distal to the left atrium, the pulmonary vein was resected at the extrapericardial portion. Conclusion Breath-hold gadolinium-enhanced 3D MR angiography is suitable for assessing invasion of the pulmonary vein and the left atrium by lung cancer.

Focal hepatic "hot spot" in superior vena cava obstruction: correlation between radiocolloid hepatic SPECT and contrast-enhanced CT.

A focal area of increased activity (a hot spot) in the hepatic hilum on a radiocolloid liver scan has been well documented in patients with superior vena cava obstruction. Portal-systemic shunting that has developed between the superior vena cava and portal vein is thought to be the cause of this finding. Although this is well known, a direct correlation with other anatomic imaging methods has rarely been shown. The authors present a case of complete superior vena cava obstruction, in which Tc-99m stannous colloid hepatic SPECT could clearly locate a hot spot in the anterior part of the quadrate lobe, where contrast-enhanced radiographic CT also revealed an area of transient abnormal enhancement. In this case, an anatomic correlation between the radiocolloid hepatic hot spot and portal-systemic shunting on radiographic CT has been clearly demonstrated.

Visualization of Normal Pulmonary Fissures on Sagittal Multiplanar Reconstruction MDCT

OBJECTIVE Delineation of the interlobar fissures on multiplanar reconstruction (MPR) images is useful to assess masses at the fissures for invasion into adjacent lobes. We performed this study to determine the appropriate MDCT protocol to visualize the interlobar fissures on sagittal MPR images. MATERIALS AND METHODS For the phantom studies, radiographic film was used to replicate the interlobar fissures. For the clinical studies, we obtained MDCT scans of 130 patients with normal interlobar fissures. Visualization of the interlobar fissures on sagittal MPR was assessed using the following scanning parameters: scan collimations of 0.5, 1, 2, and 3 mm with helical pitches of 1 and 1.5 for the phantom studies; and scan collimations of 0.5, 1, 2, and 3 mm with a helical pitch of 1.5 and a scan collimation of 2 mm with a helical pitch of 1 for the clinical studies. RESULTS To visualize fissures as a sharp line, a 0.5- or 1-mm collimation was required for the major fissure and 0.5 mm for the minor fissure in the phantom studies. In the clinical studies, 0.5-mm-collimation MPR images depicted interlobar fissures as a sharp line in all cases. Fissures on MPR images using 1-, 2-, and 3-mm collimations appeared as a sharp line in 77.5-95.0%, 0-43.3%, and 0% of cases, respectively. CONCLUSION Volume data obtained using a 1-mm collimation are required to visualize all the interlobar fissures as a sharp line on sagittal MPR images except the minor fissure and superior portion of the right major fissure, for which a 0.5-mm collimation is required.

Tc-99m MDP uptake by an advanced colon cancer lesion in a juvenile patient.

Extraosseous uptake of Tc-99m MDP has been reported in various pathologic conditions. In colon cancer, Tc-99m MDP uptake in the primary lesion is unusual, although uptake in metastatic lesions has been observed frequently. Presented here is a rare case of juvenile colon cancer in which Tc-99m MDP uptake by the primary lesion was clearly demonstrated on bone scintigraphy.

Absent skeletal uptake of (99m)Tc-hydroxymethylene diphosphonate in the presence of AL-type amyloidosis associated with multiple myeloma.

A 66-year-old woman with congestive heart failure suspected to have multiple myeloma underwent bone scintigraphy. The bone scintigraphy using technetium-99m hydroxymethylene-diphosphonate showed the following interesting findings: absent skeletal uptake; increased gastrointestinal, myocardial, and soft tissue uptake; migration of radionuclide to bilateral pleural effusions. Histopathological examination revealed that the patient suffered from AL-type amyloidosis associated with multiple myeloma. Extraosseous uptake is often observed on bone scintigraphy in amyloidosis patients, but in many cases skeletal uptake is preserved. The simultaneous presentation of these findings is rare.