Carney Complex with Multiple Intracranial Aneurysms

Carney complex is an autosomal dominant disease that displays such characteristic features as cardiac and cutaneous myxomas and spotty pigmentation of the skin. We report here on a case of Carney complex that was accompanied by increased myxoid fibroadenomas in the breast and multiple intracranial aneurysms.

(31)P MR Spectroscopic Measurement of Intracellular pH in Normal Human Hearts

PURPOSE: To assess the usefulness of intracellular pH (pHi), calculated by determining the shift of a high-energy metabolite such as inorganic phosphate (Pi) or gamma-ATP after performing MRS with ECG-gated two-dimensional 31P CSI (chemical shift imaging), as a parameter for the overall state of the intracellular milieu. MATERIALS AND METHODS: Proton decoupled 31P CSI was performed on a 1.5-T scanner using a (1)H-(31)P dual-tuned surface coil. Cardiac MRS data were obtained from eight normal volunteers aged 24-32 years with no history of heart disease. From the spectra obtained from several regions of the heart, peak position and peak area were estimated. The metabolic ratios of alpha-, beta-, gamma-ATP, PCr, Pi, phosphodiester and diphosphoglycerate were calculated, and pHi was estimated from the chemical shift of Pi and gamma-ATP resonance. We then compared the data for the anterior myocardium with those previously published. RESULTS: The major phosphorous metabolites identified in these human hearts were as follows: PCr, at -0.1 to +0.1 ppm; three phosphate peaks from ATP, with a chemical shift centered at about -2.7 ppm (gamma-ATP), -7.8 ppm (alpha-ATP), and -16.3 ppm (beta-ATP); and phosphodiester (PDE) at 2-3 ppm, inorganic phosphate (Pi) at 4.5-5.4 ppm, and diphosphoglycerate (DPG) at 5.4-6.3 ppm. The PCr/beta-ATP ratio was 2.20+/-0.17 and the PDE/beta-ATP ratio, 1.04+/-0.09. pHi readings were 7.31+/-0.23 (calculated by the shift of Pi) and 6.81+/-0.20 (calculated by the shift of gamma-ATP). Pi/PCR was 0.539, a ratio higher than that mentioned in previously published reports. CONCLUSION: The measurement of intracelluar metabolism was affected by various kinds of factors. We believe, however, that pHi readings indicate the overall state of the cardiac intracelluar milieu. An unexpected pHi readings, seen at MRS, may reflect errors in the MR procedure itself and, or in the alanytical method.

Percutaneous Intervention in the Management of Insufficient Native Arteriovenous Hemodialysis Fistulae

PURPOSE: To determine the effectiveness and patency of percutaneous intervention in insufficient native arteriovenous hemodialysis fistulae (AVFs). MATERIALS AND METHODS: Between March 1997 and September 2001, 67 cases of insufficient native AVF in 56 patients were treated by endovascular intervention. Except eight cases of insufficient native AVFs resulted from central vein lesion, PTA was performed in 48 cases, and thrombolytic therapy with or without PTA in 11. In eight of the cases, in which central vein stenosis had led to the insufficency, percutaneous transluminal angioplasty (PTA) was performed, and in three of the eight, a stent was inserted. Angiographic findings and complications, as well as success and patency rates in the non-thromobosis and thrombosis group, were evaluated; the central vein lesion group was analysed separately. RESULTS: Among 84 lesions observed at angiography, there were 54 cases of stenosis, 17 of occlusion, and 13 of combined thrombosis. The lesions were located in a proximal vein (n=51), distal vein (n=14), artery (n=6), and at the site of anastomosis (n=13). In the central vein lesion group (n=8), seven cases of stenosis and one of occlusion were noted. The overall procedural success rate was 79.1% (53/67). That is, in patients with no central vein lesion, the procedural success rate of PTA of native AVFs was 85.4% (41/48) and the patency rates of this were 83.1% at 6 months and 67.4% at 12 months. In cases of thrombolysis with/without PTA, the procedural success rate was 54.5% (6/11) and the patency rates were 83.3% at 6 months and 62.5% at 12 months. Finally, in patients with a central vein lesion, the procedural success rate was 75% (6/8) and the patency rates were 80% at 6 months and 30% at 12 months. There was one case of pseudoaneurysm formation at the puncture site of the brachial artery, which was used as the access route for intervention; one embolism in the brachial artery; and three cases of vascular spasm and two of hematoma which did not require active treatment. CONCLUSION: Percutaneous intervention offers effective and safe management of insufficient AVFs. The procedural success rate was higher for stenosis than for thrombotic occlusion.

Usefulness of Digital Subtraction Technique in the Contrast-enhanced Multi-phasic Abdominal MR angiography

PURPOSE: To assess the usefulness of digital subtraction contrast-enhanced multi-phase magnetic resonance angiography (MRA) for evaluation of the vessels of the gastrointestinal system. MATERIALS AND METHODS: Twenty-five patients who underwent abdominal MRA for evaluation of the vessels of the gastrointestinal system were included in this study. MRA was performed using a 1.5-T scanner and the 3-D turbo-FLASH sequence. Subtraction images of the arterial and portal venous phases were obtained by subtracting arterial phase images from mask images and portal venous phase images from arterial phase images, respectively. Each set of images was processed using a maximum-intensity projection (MIP) algorithm to produce three-dimensional angiograms. We compared overall image quality and the visibility of normal and abnormal vessels between subtraction and non-subtraction MRA. RESULTS: In terms of subjective image quality, subtraction and non-subtraction MRA was similar both the arterial and portal venous phases (p>0.05). During the arterial phase, subtraction MRA visualized more peripheral branches of the left gastric and superior mesenteric arteries than non-subtraction MRA (p<0.05), and during the portal venous phase, subtraction MRA demonstrated more peripheral branches of the superior mesenteric (p<0.01), splenic (p<0.05) and left portal vein (p<0.05) than non-subtraction MRA. In addition, overall visibility of the arterial and portal venous branches was superior with subtraction MRAs than with non-subtraction MRA. Both of these detected all anomalous arterial branching (n=5) and abnormal (encased or obstructed) portal veins (n=5). Subtraction MRA visualized 17 portal venous collaterals in six patients, whereas non-subtraction MRA visualized only seven collateral veins. CONCLUSION: In contrast-enhanced abdominal MRA, the digital subtraction technique permits visualization of more distal branches of the vessels of both the arterial and portal venous systems without significant degradation of image quality. The technique is particularly useful for the detection of portal venous collaterals in patients with portal hypertension.

Leukoencephalopathy Following CNS Prophylaxis Therapy in Pediatric Leukemia: MR Imaging Findings

PURPOSE: To evaluate the MR imaging findings and the usefulness of MR imaging in the diagnosis and followup of leukoencephalopathy following CNS prophylaxis therapy in pediatric leukemia. MATERIALS AND METHODS: We retrospectively evaluated the MR imaging findings of eight children with white matter abnormalities on MR out of seventeen acute leukemic patients with various neuropsychiatric symptoms who received intrathecal methotrexate administration, with or without cranial irradiation. In all cases, initial MR was performed within a week of the onset of neuropsychiatric symptoms. Follow-up MR was performed one to sixteen months after initial study, and the MR imaging findings were compared with the initial findings. RESULTS: The initial MR imaging findings were classified into three categories: focal or multifocal white matter abnormalities (3/8), and diffuse white matter abnormalities without enhancement (3/8), and diffuse white matter abnormalities with enhancement (2/8). At follow-up MR, diffuse or focal atrophic changes were noted in all children. White matter abnormalities improved in two out of three patients with focal or multifocal white matter abnormalities. In five with diffuse white matter abnormalities, the extent of these showed no significant change, but contrast enhancement was markedly reduced in two children in whom diffuse white matter abnormalities with enhancement had been demonstrated. CONCLUSION: In pediatric leukemia, the MR imaging findings of leukoencephalopathy following CNS prophylaxis therapy are variable, but are specific with the clinical history of neuropsychiatric symptoms after intrathecal methotrexate administration, with or without cranial irradiation. The MR imaging is valuable in the diagnosis and follow-up of leukoencephalopathy following CNS prophylaxis therapy in pediatric leukemia.

Ultrasound-guided Biopsy of the Thickened Peritoneal Reflections: Efficacy and Diagnostic Role in the Differential Diagnosis of Peritoneal Tuberculosis and Peritoneal Carcinomatosis

PURPOSE: To evaluate the accuracy and safety of ultrasound-guided biopsy of the thickened peritoneal reflections and to determine the efficacy and diagnostic role of this procedure in the differential diagnosis of peritoneal tuberculosis and peritoneal carcinomatosis. MATERIALS AND METHODS: Twenty-seven patients with only mildly thickened (25 mm or less) peritoneal reflections without apparent mass formations, and in whom imaging findings were not diagnostic, underwent ultra-sound-guided biopsy. Five-MHz linear or convex linear array transducers were used for ultrasound guidance,and an automated gun with 18-gauge (n = 23) or 20-gauge (n = 4) needles for tissue sampling. Biopsies were performed on the thickened parietal peritoneum (n = 9), greater omentum (n = 11), and small bowel mesentery (n = 7), and the results were compared with the final diagnosis determined by adiologic/clinical follow-up (n = 17) or laparoscopic biopsy (n = 10). Complications and changes in hemoglobin and hematocrit levels after the procedure were evaluated. RESULTS: Specimens adequate for pathologic examination were obtained in all 27 patients. The histopathologic results were metastatic carcinomatosis (n = 15), peritoneal tuberculosis (n = 8), and chronic granulomatous inflammation (n = 4). Specific pathologic diagnosis was obtained in all patients except the four with chronic granulomatous inflammation. Differentiation between benignancy and malignancy was possible in all patients and the histopathologic specific accuracy rate was 100%. No clinically significant complications were observed. In 24 patients with ascites at the site of the biopsy, transient bleeding was observed immediately after the procedure, but this stopped spontaneously within a few minutes. Post-procedural hemoglobin and hematocrit levels were only minimally lower (mean values of 0.9g/dL and 3.0%, respectively) than pre-procedurally. CONCLUSION: Ultrasound-guided biopsy of thickened peritoneal reflections is a safe and effective diagnostic procedure and is useful in the differential diagnosis of peritoneal tuberculosis and peritoneal carcinomatosis.

Usefulness of Measurement of Circulation Time Using MgSO4: Correlation with Time-Density Curve Using Electron Beam Computed Tomography

PURPOSE: To determine the usefulness of MgSO 4 for measuring the systemic circulation time. Material and Methods: Systemic circulation time, defined as elapsed time from the injection of MgSO 4 solution to the point of pharyngeal burning sensation, was measured in 63 volunteers. MgSO 4 was injected into a superficial vein of an upper extremity. Using dynamic electron beam computed tomography at the level of the abdominal aorta and celiac axis, a timeintensity curve was plotted, and for these two locations, maximal enhancement time was compared. RESULTS: For 60 of the 63 subjects, both systemic circulation time and maximal enhancement time were determined. Average systemic circulation time was 17.4 (SD: 3.6) secs. and average maximal enhancement times at the level of the abdominal aorta and celiac axis were 17.5 (SD: 3.0) secs. and 18.5 (SD: 3.2)secs., respectively. Correlation coefficients between systemic circulation time and maximal enhancement time for the abdominal aorta and celiac axis were 0.73 (p<0.01) and 0.73 (p<0.05) respectively. CONCLUSION: The systemic circulation time demonstrated by MgSO 4 injection and maximal enhancement time for the abdominal aorta showed significant correlation. Thus, to determine the appropriate scanning time in contrast-enhanced radiological studies, MgSO 4 can be used instead of a test bolus study.

Neurilemmoma of extremities: MR findings

Six patients with twenty histologically proven neurilemmomas of the extremities were studied using magnetic resonance(MR) imaging. The size, number, signal intensity on spin-echo T1WI(TR 500-650ms/TE 14-25ms)and gradient -echo (TR 200-600ms/TE 14-20ms; flip angle 25-30)image, enhancement pattern, detectability of nerve of origin, nerve-lesion relationship, and presence of a capsule were analyzed. The masses ranged from 1 to 12cm in longitudinal diameter and originated from the median nerve, ulnar nerve, sciatic nerve, radial nerve, and tibial nerve. All the nerve tracts except for those of 5 lesions, which could not be detected due to their small diameter, were visualized as low intensity tubular structures. All visible nerve tracts were situated along the periphery of the lesion and this finding was considered to be specific for neurilemmona. All neurilemmomas were isointense with the surrounding muscle on spin-echo T1WI and hyperintense on gradient-echo image. After a GD-DTPA injection, all masses showed moderate or marked enhancement and more prominent inhomogeneity than that on nonenhanced scan. In 19 out of 20 lesions(95%), a low signal intensity capsule surrounding the masses could be seen. Four of the six patients showed multiple masses, which was unusual as neurilemmoma usually arises as a solitary mass. In conclusion, the MR findings, especially the eccentric location of the mass lesion from the nerve of origin and the presence of a capsule, were useful in making a diagnosis of neurilemmoma of the extremity and that multiple neurilemmomas were not uncommon.