New and reliable MRI diagnosis for progressive supranuclear palsy.

OBJECTIVE: To evaluate the area of the midbrain and pons on mid-sagittal MRI in patients with progressive supranuclear palsy (PSP), Parkinson disease (PD), and multiple-system atrophy of the Parkinson type (MSA-P), compare these appearances and values with those of normal control subjects, and establish diagnostic MRI criteria for the diagnosis of PSP. METHODS: The authors prospectively studied MRI of 21 patients with PSP, 23 patients with PD, 25 patients with MSA-P, and 31 age-matched normal control subjects. The areas of the midbrain tegmentum and the pons were measured on mid-sagittal MRI using the display tools of a workstation. The ratio of the area of the midbrain to the area of the pons was also evaluated in all subjects. RESULTS: The average midbrain area of the patients with PSP (56.0 mm2) was significantly smaller than that of the patients with PD (103.0 mm2) and MSA-P (97.2 mm2) and that of the age-matched control group (117.7 mm2). The values of the area of the midbrain showed no overlap between patients with PSP and patients with PD or normal control subjects. However, patients with MSA-P showed some overlap of the values of individual areas with values from patients with PSP. The ratio of the area of the midbrain to the area of pons in the patients with PSP (0.124) was significantly smaller than that in those with PD (0.208) and MSA-P (0.266) and in normal control subjects (0.237). Use of the ratio allowed differentiation between the PSP group and the MSA-P group. CONCLUSION: The area of the midbrain on mid-sagittal MRI can differentiate PSP from PD, MSA-P, and normal aging.

Unusual imaging appearances of pancreatic serous cystadenoma: correlation with surgery and pathologic analysis.

BACKGROUND: We describe imaging and pathologic features of serous cystadenoma of the pancreas on multislice helical computed tomography CT (MS-CT) and surgical resection. METHODS: Radiologic and pathologic features were analyzed in five patients. All patients underwent MS-CT and digital subtraction angiography (DSA), and four patients underwent magnetic resonance (MR) imaging. Preoperatively, three cases showed radiologic evidence of mainly solid appearance on MS-CT, and the suspected diagnoses were solid pancreatic tumors (patients 1-3). The other two cases showed radiologic evidence of macrocystic tumor of the pancreas, and the suspected diagnoses were mucinous cystic tumors (cases 4 and 5). All patients underwent surgery, and the diagnosis of serous cystadenoma was confirmed on pathologic examination. RESULTS: In three cases that showed a solid appearance on MS-CT, a microcystic appearance was identified on microscopic examination, and the tumors were found to be hypervascular lesions on multiphasic contrast-enhanced CT and DSA. In cases 1 and 2, the lesions showed high intensity with internal septation on T2-weighted MR images. In two cases, the tumors were classified as a macrocystic variant of serous cystadenoma, and no mural nodules, papillary projections, or calcifications were seen in the tumors. CONCLUSION: Imaging appearance of serous cystadenoma on MS-CT is various and sometimes indistinguishable from that of solid tumor or mucinous cystic tumors of the pancreas. Imaging findings of hypervascularity and a well-marginated high-intensity lesion with internal septation on T2-weighted MR imaging may be crucial to identify serous cystadenoma that contains no visible cystic compartments on MS-CT.

Isolated dissection of the superior mesenteric artery: CT findings in six cases.

Dissection of the superior mesenteric artery (SMA) not associated with aortic dissection is rare. The purpose of this study is to describe the computed tomographic (CT) findings of this condition. We studied the CT findings of six patients with isolated dissection of the SMA. CT demonstrated thrombosis of the false lumen or intramural hematoma (n = 4) and/or intimal flap (n = 4) in all six patients. Other CT findings were enlarged diameter of the SMA (n = 5), increased attenuation of the fat around the SMA (n = 5), and hematoma in the mesentery with hemorrhagic ascites (n = 1). CT is useful for the diagnosis of isolated dissection of the SMA, and increased attenuation of the fat around the artery is considered the key to the diagnosis when no definite findings are evident.

Transcatheter embolization of arteriovenous malformations in Cowden disease.

A patient with Cowden disease and multiple arteriovenous malformations (AVMs) that resulted in high output heart failure is described. Cowden disease is a familial syndrome characterized by endodermal, mesodermal and ectodermal dysplasia causing benign and malignant tumors of the skin, breast, gastrointestinal tract, and thyroid gland. Our patient had gastrointestinal polyposis, a right renal tumor, a left lung tumor, an adenomatous goiter, and typical dermatologic findings such as facial papules, acral keratosis, gingival papillomatosis and hemangiomas. AVMs were observed in the pelvis, cervical vertebra, liver, and right supraclavicular area. Transcatheter embolization was performed 7 times for the pelvic AVMs, but the effect decreased with repetition and the patient died of heart failure 2 years after the first embolization. The serum levels of tissue plasminogen activator (t-PA), platelet-derived growth factor (PDGF), hepatocyte growth factor (HGF), vascular endothelial growth factor (VEGF), and transforming growth factor beta1 were high, suggesting that these angiogenic molecules may play a role in the pathogenesis of AVMs in Cowden disease.

Emergent right coronary artery thrombectomy with a jet aspiration thrombectomy catheter.

A saline-jet aspiration thrombectomy (JAT) catheter was used in a patient with acute myocardial infarction. A right coronary arteriogram showed complete thrombotic occlusion at the proximal segment. With this catheter the thrombus was removed without complications in 5 sec. The patient underwent percutaneous transluminal coronary angioplasty and placement of a Palmaz-Schatz stent after successful thrombectomy. Thrombectomy with a JAT catheter was very useful in this patient.

[Minimum intensity projection image and curved reformation image of the main pancreatic duct obtained by helical CT in patients with main pancreatic duct dilation].

Contrast enhanced CT was performed in seven patients with pancreatic disease (chronic pancreatitis, n = 3; pancreatic head cancer, n = 2; mucin-producing pancreatic tumor, n = 2) who showed dilation of the main pancreatic duct (MPD) Minimum intensity projection (Min-IP) images of the pancreas were obtained using multi-projection volume reconstruction (MPVR) software by selecting an oblique slab that contained the entire MPD. Curved reformation (CR) images were obtained using multiplanar reformation (MPR) software by tracing the MPD on the Min-IP image. Both Min-IP images and CR images clearly showed the dilated main pancreatic duct in all seven patients. In three of the seven, obstruction of the MPD in the pancreatic head and the cause of obstruction (tumor mass, n = 2; caliculus, n = 1) were also clearly seen. Min-IP and CR images seem to be useful for the diagnosis of pancreatic diseases.

Retroperitoneal malignant mesenchymoma: imaging findings in five cases.

BACKGROUND: To describe computed tomographic (CT), magnetic resonance (MR), ultrasonographic (US), and angiographic findings of retroperitoneal malignant mesenchymoma with emphasis on CT findings. METHODS: Five CT, four US, four angiography, and two MR studies were obtained in five patients with pathologically proven retroperitoneal malignant mesenchymoma. RESULTS: Tumors were larger than 10 cm (n = 4), well-circumscribed and heterogeneous (n = 4), and with massive intratumorous calcifications (n = 3) on plain CT or US. Tumors showed heterogeneous enhancement on contrast-enhanced CT scans (n = 4) and moderate hypervascularity with heterogeneous staining on angiography (n = 3). Tumors were essentially hypointense on T1-weighted MR images (n = 2) and heterogeneous hyperintense on T2-weighted MR images (n = 2). Plain CT showed a fat-dense structure in a tumor in one patient. CONCLUSIONS: The radiologic findings of large expansile heterogeneous masses in the retroperitoneum, especially with massive calcifications, were considered to be typical of malignant mesenchymomas.

Hydraulic analysis of the functional properties of saline-jet aspiration thrombectomy catheters.

The purpose of this paper is to clarify the functional properties of a saline-jet aspiration thrombectomy catheter based on hydraulics. This catheter, developed by the authors, aspirates intravascular thrombi by means of the effect of a high-speed jet. We have derived the relationships between Qs, Qa, and p(n), where Qs is the water supply rate, Qa is the water aspiration rate and p(n) is the negative pressure created in the distal lumen of the catheter. The relationships are represented by simple equations using c1 and c2, where c1 and c2 are coefficients proper to the catheter. We have obtained c1 and c2 experimentally for three types of catheter with different distal shapes. Two practical conclusions are derived from this study. First, making a short taper at the distal end increases the negative pressure created and is advantageous for thrombus aspiration. Second, making the diameter of the inner tube and nozzle smaller is essential for improving the aspiration ability of the catheter.

[Three-dimensional images of hepatic tumors and hepatic vessels obtained by helical computed tomography].

Helical computed tomography was performed with intravenous contrast material administration in ten patients with hepatic tumors (metastatic tumor, n = 6; hepatocellular carcinoma, n = 4). Maximum intensity projection (MIP) images of intrahepatic portal venous branches and hepatic veins, and shaded surface display (SSD) images of the hepatic tumors were reconstructed for each patient. The MIP image and SSD image were fitted to overlap on a single display to obtain three-dimensional (3-D) images showing both the hepatic vessels and hepatic tumors. Subsegmental localization of the tumors determined from the 3-D images proved to be correct in all of the six patients who received hepatic resection after examination. 3-D images seem to be useful for preoperative assessment of hepatic tumors.