bluuebunny/crossref_metadata_2025 huggingface dataset:
Mr Imaging, Flow and Motion
Authors: Ståhlberg F. , Ericsson A. , Nordell B. , Thomsen C. , Henriksen O. , Persson B. R. R.
Published: June 2015

The present work is intended as a nonmathematical review of the role of flow and motion in nuclear magnetic resonance (MR) imaging. A historical review of MR flow measurement techniques is given, followed by a short overview of flow models in vitro and in vivo. The theory behind the influence of motion on the modulus and phase MR signal information is discussed and effects such as washin/washout, flow-induced signal void, phase offset, and phase dispersion are defined. A simple approach to the concept of MR angiography is given, and methods for quantitative flow measurements such as the phase mapping technique, are surveyed. Aspects of the measurement of diffusion and mirocirculation are given, and finally, an overview of the role of MR flow imaging in present and future clinical application is given.
Mr Imaging of Intradural Extramedullary Tumors
Authors: Li M. H. , Holtås S. , Larsson E.-M.
Published: June 2015

Thirty-one consecutive intradural extramedullary spinal tumors examined with MR at 0.3 T were reviewed. In 13 of the patients myelography had been performed. There were 11 patients with meningeoma, 14 with neuroma, one ependymoma, 3 metastases, and 2 lipomas. All tumors were surgically removed and verified by histology. The intradural extramedullary location of the tumors was accurately assessed by MR imaging in all patients and by myelography in 10 of 13. The MR diagnoses were in accordance with the histologic findings in 74% of cases. Compression of the spinal cord or cauda equina with widening of the subarachnoid space above and below the mass or outward displacement of epidural fat was characteristic of the intradural extramedullary tumors. The signal intensity of meningeoma as well as of neuroma was slightly lower or equal to that of the cord on T1-weighted images, and equal to or higher than cord signal on T2-weighted images. Neuroma had a lower signal intensity on T1-weighted images and a higher signal intensity on T2-weighted images than meningeoma. Meningeoma appeared more homogeneous than neuroma and had a broad base towards the dura.
Radiologic Approach to Bile Duct Cysts in Adults
Authors: Hagen G. , Kolmannskog F.
Published: June 2015

Radiologic findings in 7 adult patients with bile duct cysts were reviewed. Endoscopic retrograde cholangiopancreatography (ERCP) was performed in 6 patients, percutaneous transhepatic cholangiography (PTC) in 4, CT and ultrasonography (US) in 4, and angiography in 6. ERCP and PTC were the only methods which exactly showed the extent of the cysts and the anomalous pancreatico-biliary junction present in 5 patients. ERCP and PTC were mandatory for surgical planning and treatment. Pancreas divisum was revealed in 3 patients, all of whom had suffered from acute pancreatitis. Intracystic adenocarcinoma was depicted at cholangiography in 2 patients. US and CT were valuable in showing cystic masses between the pancreatic head and the hilum of the liver, but in no patient was the diagnosis made by any of these methods. Angiography was performed for preoperative vascular mapping.
Regenerative Nodules in Hepatic Cirrhosis
Authors: Van Beers B. , Trigaux J. P. , Grandin C. , Jamart J. , Demeure R. , Geubel A. , Brenard R. , Melange M. , Dardenne A. N. , Pringot J.
Published: June 2015

To evaluate the accuracy of surface coil gradient-echo (GRE) imaging in the detection of regenerative nodules of hepatic cirrhosis, 53 patients with diffuse liver disease, among whom 31 had cirrhosis, were prospectively investigated. Three GRE sequences acquired with a surface coil were used in the study: a T2*-weighted, a T1-weighted, and a gadopentetate-enhanced sequence. ROC analysis showed that two surface coil GRE sequences were superior to conventional T2-weighted spin-echo imaging acquired with a body coil for the detection of regenerative nodules. The detection of regenerative nodules was also more accurate for the diagnosis of cirrhosis than the measurement of the caudate-to-right lobe ratio. These results suggest that there could be a potential for surface coil GRE imaging in the assessment of the characteristic macroscopic alterations of cirrhosis.
CT and Angiography in Chronic Liver Disease
Authors: Aspestrand F. , Kolmannskog F.
Published: June 2015

Detailed correlation of CT and angiographic findings in a retrospective analysis of 25 cases of portal hypertension is presented. The largest diameters of the common and proper hepatic arteries, the portal, splenic, and superior mesenteric veins, and perigastric veins were measured by the two methods, including a CT control series of 20 subjects. The splenic transverse diameter was also measured. Portosystemic collaterals and concomitant pathology disclosed by the two methods were compared. A ratio of nearly 1 was found between vessel diameters measured by angiography and CT, and about 1.3 for splenic size, applying uncorrected measures from angiographic films and a vernier caliper on CT studies. The diameters of hepatic arteries, splenic, and superior mesenteric veins and spleens were significantly larger than those of controls. Except for demonstrating arterial details and esophageal varices, CT was found equal or superior to angiography in mapping portosystemic collaterals, and to disclose concomitant pathology.
Concomitant Changes in Mr Image and Morphology Induced by Glucose and Fructose in B16 Mouse Melanomas
Authors: Naeser P. , Thuomas K. Å. , Roberto A. , Larsson B. S.
Published: June 2015

The short proton relaxation times in the MR images of malignant melanomas make them different from most other tumors. We have previously shown that the T1 and T2 signals may be significantly influenced when the water distribution of the tumor is changed in vivo and in vitro. In the present work T1 and T2 were estimated and compared with the electron microscopy picture in subcutaneously implanted B16 melanomas in mice. Two hours after the mice were given an i.p. injection of 0.9% NaCl containing 10% glucose and 10% fructose (9 mice) both the T2 components were markedly and the T1 slightly prolonged. At the same time the electron microscopy picture displayed swelling of the melanocytes together with a marked decrease in number and size of their mitochondriae. There were no changes in the MR image or the melanocyte structure in control mice injected with 0.9% NaCl (9 mice) or 0.9% NaCl containing 10% fructose. It is concluded that the changed MR image may be coupled to the metabolism in melanoma.
Phagocytic Properties of Granulocytes after Intravenous Injection of Ioxaglate or Iohexol
Authors: Rasmussen F. , Georgsen J. , Antonsen S. , Grunnet N.
Published: June 2015

To evaluate the influence of radiographic contrast media (CM) on human granulocytes, the ability of these cells to ingest latex particles after intravenous injection of ioxaglate and iohexol was investigated. Both CM inhibited the phagocytic properties of granulocytes; the inhibition was the most pronounced immediately after the injection, but inhibition was also observed 60 min after injection of ioxaglate. The inhibition 1 and 5 min after injection of CM was more pronounced after injection of ioxaglate than after injection of iohexol. However, this difference between the 2 CM was not significant. Significant inhibition of phagocytosis was found for mannitol solutions with osmolalities higher than 369 mOsm/***1. Significant inhibition of phagocytosis was observed when granulocytes were isolated with either Hypaque/Ficoll or Percoll gradient centrifugation and then incubated with diatrizoate. Thus the ability of granulocytes to phagocytize latex particles was inhibited after i.v. injection of 50 ml ioxaglate or iohexol. Part of this inhibition may be due to hyperosmolality.
Iliac Artery Stenting — Clinical Experience with the Palmaz Stent, Wallstent, and Strecker Stent
Authors: Hausegger K. A. , Lammer J. , Hagen B. , Flückiger F. , Lafer M. , Klein G. E. , Pilger E.
Published: June 2015

A total of 82 iliac artery lesions (62 stenoses and 20 occlusions) were treated with 3 different types of endovascular metallic stents (12 lesions with the Palmaz stent, 36 with the Wallstent, and 34 with the Strecker stent). The complication rate was 12%. Occlusion of 2 Wallstents occurred 4 and 12 weeks after stent placement, respectively. Both stents were recanalized by local fibrinolysis. One Strecker stent occluded after 8 months. The observation period was 3 to 26 months (mean 9.7 months). The patency rate with secondary intervention (fibrinolysis) was 100% after 3 and 6 months, and 98% after 9 months. All 3 stent designs turned out to be effective in the treatment of complicated iliac artery occlusive disease.
Mr Imaging of Acute Myocardial Infarction in Pigs Using GD-Dtpa-Labeled Dextran
Authors: Wikström M. , Martinussen H. J. , Wikström G. , Ericsson A. , Nyman R. , Waldenström A. , Hemmingsson A.
Published: June 2015

Myocardial infarctions were induced in 12 pigs. In 6 pigs, dextran-(Gd-DTPA)15 (≈0.1 mmol Gd/kg b.w.) was injected i.v. 4 to 4.5 hours after coronary artery occlusion. ECG gated MR images were obtained repeatedly before (n = 4) and after (n = 6) contrast medium injection. Relaxation times in blood samples were measured repeatedly. The animals were sacrificed 2 hours after contrast medium administration. The hearts were excised, reexamined in the MR equipment and stained with triphenyltetrazolium chloride (TTC) in order to define areas of infarction. The remaining 6 pigs were sacrificed 6 hours after occlusion without administration of contrast medium. These hearts were only imaged ex vivo. In vivo, the infarctions could not be identified with or without dextran-(Gd-DTPA)15. Ex vivo, without contrast medium, the infarctions had an increased signal intensity, most pronounced in the T2-weighted images. Dextran-(Gd-DTPA)15 caused a prolonged, pronounced shortening of T1 and T2 in blood samples. The infarct demarcation improved in the T1-weighted images after injection of dextran-(Gd-DTPA)15, due to a moderate enhancement in normal myocardium and a stronger enhancement at the periphery of the infarctions, while the central parts of the infarctions were only weakly enhanced.
Hilar Cholangiocarcinoma
Authors: Yamashita Y. , Takahashi M. , Kanazawa S. , Charnsangavej C. , Wallace S.
Published: June 2015

Sixty-seven patients had hilar cholangiocarcinomas which were divided into 3 types based on tumor morphology as observed on cholangiography and CT. The pathology, vascularity, and pattern of tumor spread of these types were compared. Most of the infiltrative tumors (n = 44) were scirrhous adenocarcinomas, which on CT showed poor or no contrast enhancement with frequent lymph node metastases and liver atrophy. At angiography, there was vascular encasement in 52%, in rare cases neovascularity, and tumor stain. The exophytic type (n = 19) was divided into 2 subgroups depending on the main location of the tumor. The nodular subtype (n = 16) was mainly inside the liver and somewhat hypervascular similar to peripheral cholangiocarcinoma, often with intrahepatic metastases. The periductal subtype (n = 3) was hypovascular, similar to the infiltrative cholangiocarcinoma, and had a tendency to spread along the portal vein. The intraductal type (n = 4) was observed as a filling defect on cholangiography. CT revealed an intraluminal low density mass. Histologically, they were papillary adenocarcinomas. The radiologic types of hilar cholangiocarcinoma showed different characteristics with regard to pathologic findings, vascularity, and pattern of spread.
Monte Carlo Simulation of Multiple Scattering in Compton Spectroscopy
Authors: Persliden J.
Published: June 2015

The Compton scattered photons from a scattering medium can be analyzed in a Compton spectrometer and the primary energy spectrum derived using the Compton equation. Since the reconstruction algorithm assumes that only singly-scattered photons from the scatterer are detected, multiply-scattered photons introduce errors into the measurements unless they can be accurately corrected for. In this work, a Monte Carlo collision density estimator was used to determine the contribution from photons multiply-scattered from a Lucite scatterer in the form of a square rod. The ratio of multiply- to singly-scattered photons was determined for rod thicknesses from 0.5 to 5 mm and photons of energy 20 to 110 keV. The ratio in percent can be well approximated as a linear function of energy with slope 2.2. For thicknesses below 2 mm, the ratio is less than 5% at all energies.
Gadodiamide Injection and Gadopentetate Dimeglumine
Authors: Myhr G. , Rinck P. A. , Børseth A.
Published: June 2015

A double-blind, randomized parallel phase III study in MR imaging of the central nervous system was conducted to compare the safety and diagnostic utility of gadodiamide injection and gadopentetate dimeglumine at a dose of 0.1 mmol/kg b.w. in 60 adult patients. Seven patients in the gadodiamide injection group experienced 10 adverse events, 5 of the events possibly related to the contrast agent. In the gadopentetate dimeglumine group 5 patients reported 3 contrast agent-related adverse events out of 8 events. All events were transient and required no treatment. Seven incidents of patient discomfort, and some minor changes in vital signs and laboratory parameters were of no clinical concern. Contrast enhancement was observed in 60% and 44% of the patients with structural abnormalities in the gadodiamide injection group and gadopentetate dimeglumine group, respectively. No difference in overall efficacy was observed. Gadodiamide injection was found to be a safe and effective contrast agent.
Diagnosis of Aneurysm of Superior Thyroid Artery by CT and Mr Imaging
Authors: Fujimoto H. , Yasuda S. , Kashimada A. , Sato D. , Takebayashi S. , Kunimoto M. , Arimizu N.
Published: June 2015

A 51-year-old man presented with a nonpulsatile anterior neck mass which suggested a thyroglossal duct cyst. At CT a small cystic mass was revealed. The mass contained a well-defined, crescent-shaped, low-density area with homogeneous contrast enhancement. On MR T2-weighted spin-echo and gradient-echo images the mass was as hyperintense as the neck vessels. Angiography and operation confirmed an aneurysm of the left superior thyroid artery with a mural thrombus.
Necrosis Observed on CT Enhancement is of Prognostic Value in Soft Tissue Sarcoma
Authors: Gustafson P. , Herrlin K. , Biling L. , Willén H. , Rydholm A.
Published: June 2015

Fifty-one patients with deep-seated soft tissue sarcoma of the extremities and trunk wall were examined with contrast-enhanced CT for presence of nonenhanced tumor areas (CT necrosis). After a median follow-up time of 3 years, 19 of the 41 patients with CT necrosis had developed metastases, compared to none of the 10 patients who had tumors without CT necrosis. Tumors with CT necrosis were larger than tumors without, but in tumors of similar size, absence of CT necrosis was a favorable prognostic sign.
Addition of Sodium to the Nonionic Contrast Medium Iohexol during Coronary Angiography in Man
Authors: Vik-Mo H. , Bjørkhaug A. , Danielsen R. , Følling M. , Kloster Y. , Skinningsrud K.
Published: June 2015

It has recently been claimed that lack of sodium in nonionic contrast media may increase the risk of ventricular arrhythmias during coronary angiography. Thus, the influence of sodium addition to the nonionic contrast medium iohexol was studied in 75 patients with severe coronary heart disease. The study design was randomized, parallel and double-blind, and iohexol was given either with or without addition of NaCl (28 mmol/l). Both formulations induced a transient drop in arterial blood pressure, and prolongation of the QT interval and QRS duration at 10 s only (p < 0.01). The electrical QRS axis was significantly changed by the coronary artery injections after 10 s, but not later. No differences between iohexol with and without NaCl were observed for any of the variables studied. No serious arrhythmias were observed. Thus, the addition of NaCl (28 mmol/l) to iohexol did not influence the electrocardiographic or hemodynamic changes induced by iohexol during coronary angiography.
Ct and Mr Imaging of Primary Tumors of the Masticator Space
Authors: Aspestrand F. , Boysen M.
Published: June 2015

A retrospective study of CT and MR examinations in 14 patients with benign and malignant tumors originating in the masticator space is presented. At presentation, 12 patients revealed tumor extension to adjacent regions and spaces. Perineural tumor spread along trigeminal nerve branches to the cavernous sinus and orbits was combined with facial pain, and/or numbness, ophthalmoplegia, and exophthalmus. Detailed analysis of tumor growth and spread, enhancement and signal features at CT and MR imaging indicated that tumor histology was, with a few exceptions, nonspecific. More extensive growth and bone destruction was noted only among malignant tumors. MR imaging was found superior to CT in delineating tumor extension due to better soft tissue contrast resolution and multiplanar imaging. Posttreatment examinations were available in 11 patients and showed long-standing regional edema of the adjacent temporal lobe and masticator muscles in 4 out of 5 patients without clinical evidence of tumor. In 6 patients, CT and MR features were found almost unchanged with only small size differences after various forms of treatment.
Diagnosis of Tracheal Carcinoma at Chest Radiography
Authors: Manninen M. P. , Paakkala T. A. , Pukander J. S. , Karma P. H.
Published: June 2015

All of the 95 primary tracheal carcinomas registered in Finland during 1967 to 1985 were reviewed. Chest radiographs of 44 patients were available. A tracheal tumor was detected in 8 cases (18%) in the primary examination and according to the review all the detected tumors were larger than 15 mm. However, when the same radiographs were reexamined by a senior radiologist, the tumor was identified in the correct site in 66%. This percentage parallels the results of high kV tracheal radiography (69%) performed on 32 patients. Tumors involving anterior or posterior wall and tumors near the bifurcation were the most difficult to detect.
Clinical Stage I Carcinoma of the Cervix
Authors: Lien H. H. , Blomlie V. , Iversen T. , Tropé C. , Sundfør K. , Abeler V. M.
Published: June 2015

Using MR imaging with a body coil parametrial invasion was determined prospectively in 169 consecutive patients considered on the basis of clinical examination to have carcinoma confined to the cervix. After radical hysterectomy correlation with histologic examination was performed for the left and right parametrium separately. The criterion for parametrial invasion was a high-signal-intensity lesion with disruption of the full thickness of the cervical stroma combined with areas of abnormal signal intensity within the parametrial region on T2-weighted images. Histologic examination showed that 18 parametria in 13 patients were invaded by tumor. MR had an overall accuracy of 93%, a sensitivity of 89%, and a specificity of 93% in demonstrating parametrial involvement. Positive and negative predictive values were 43% and 99%. The main weakness of MR was 21 false-positive tests. This represents a limitation when MR is performed with a body coil.
Peliosis of the Spleen Associated with a Paraganglioma
Authors: Engel P. , Tjalve E. , Horn T.
Published: June 2015

We report a case of splenic peliosis imitating metastases on CT. The patient was a 44-year-old man who previously had a retroperitoneal paraganglioma surgically removed. Peliosis must be considered a potential differential diagnosis of hypodense foci of the spleen seen on CT.
MR Angiography of in Situ and Transplanted Renal Arteries
Authors: Smith H.-J. , Bakke S. J.
Published: June 2015

Three-dimensional (3D) time-of-flight (TOF) MR angiography (MRA) was performed in 34 patients with suspected renal artery disease. In situ (i.e., nontransplanted) renal arteries were studied with MRA in 14 patients. Of these, 12 had conventional angiography for comparison. Twenty-four MRAs of transplanted renal arteries were obtained in 20 patients; 8 of these had angiography as well. Significant stenoses of in situ renal arteries were diagnosed with a sensitivity of 100% and a specificity of 95%. The stenoses were all proximal; 3D TOF MRA proved inadequate for depiction of peripheral renal arteries. MRA and angiography showed good agreement between findings in 7 of 8 patients with renal transplants. In one patient with a renal transplant, MRA showed a significant stenosis of the arterial anastomosis which appeared completely normal at i.a. DSA, indicating that findings at MRA still need to be confirmed by more established alternative methods.
Intravascular Ultrasonographic Assessment of Thrombus Formation on Central Venous Catheters
Authors: Bolz K.-D. , Aadahl P. , Mangersnes J. , Rødsjø J. Å. , Jørstad S. , Myhre H. O. , Angelsen B. A. J. , Nordby A.
Published: June 2015

In vitro experiments were performed in order to investigate the appearance of different types of central venous catheters at intravascular ultrasonography. The experiments were repeated with artificially produced thrombi which were made adherent to the catheter wall. All thrombi larger than 1 mm could be identified. In a clinical study including 12 patients who had a central venous catheter, transfemoral intravascular ultrasonography was performed. The catheters had been in place for an average period of 54 days (range 1–360 days). In 3 patients a catheter thrombus, mural thrombus, or occlusive vein thrombosis was found. In 2 of these patients the catheter was occluded, in the 3rd patient it was malpositioned into the contralateral brachiocephalic vein. There were no complications following the ultrasonographic procedures. Mean catheterization time was 7.5 min (range 3–20 min). The advantages of this new method compared with conventional phlebographic studies and its impact on further clinical investigations are discussed.
Acute Electrolyte Disturbances in Coronary Sinus during Left Coronary Arteriography in Man
Authors: Hayakawa K. , Mitsumori M. , Uwatoko H. , Monji T. , Okuno Y. , Torizuka T. , Satoh Y. , Tanaka F. , Kitamura K. , Misaki T.
Published: June 2015

Electrolyte disturbances, particularly reduction of ionized calcium, induced by iodinated contrast media (CM) are important considerations in coronary arteriography. A study was conducted in 24 patients to evaluate the acute electrolyte alterations in the coronary sinus during left coronary arteriography. During left coronary arteriography, coronary sinus blood was withdrawn for measurement of electrolytes. The CM used were diatrizoate, ioxaglate, iohexol, and iopamidol. The hematocrit was decreased moderately by all 4 CM used at 5 s and returned to the control level at 15 s. The level of ionized calcium was decreased by all CM at 5 s. Prolonged reduction of ionic calcium was observed with diatrizoate and ioxaglate at 15 s. The level of potassium was almost unchanged by diatrizoate and ioxaglate in spite of hemodilution, which may lead us to a hypothesis that potassium can be released from the intracellular spaces such as red blood cells and vascular endothelial cells. Thus the depression of left ventricular function might be caused not only by reduction of ionized calcium, but also by a relative increase in the level of serum potassium.
Expandable Metallic Endoprostheses for Biliary Obstruction
Authors: Mygind T. , Hennild V.
Published: June 2015

Expandable metal stents (20 Gianturco Z-stents and 1 Strecker stent deployed through 8.5 F sheaths) were used with initial success for palliating bile duct obstruction in 10 patients, 8 with malignant and 2 with benign strictures. Short-term failure occurred in one patient after 2 weeks, one died of unrelated causes after 10 days, and one remained jaundiced due to fulminant liver metastases. In the remaining 7 patients the obstruction was markedly palliated, with normalization of the serum bilirubin. Four have died without recurrent bile duct obstruction after a mean of 5.9 months, the 2 with benign strictures are well after 4 and 7 months, and one patient is presently palliated with a plastic endoprosthesis following reocclusion after 4 months. Expandable stents were easier to insert than conventional percutaneous endoprostheses of plastic polymers, and had longer patency in several patients, but reocclusion by tumor growth remains a constant threat in malignant disease. Metallic stents may be the therapy of choice in recurrent benign strictures, although the definitive conclusion needs longer observation and larger materials.
Duplex Doppler Scanning with Prostaglandin E1 in the Diagnosis of Cavernovenous Leakage
Authors: Nisen H. O. , Saarinen O. , Ruutu M. L. , Edgren J.
Published: June 2015

The aim of this study was to find out the normal response of the duplex Doppler (DD) parameter resistance index (RI) during a high dose prostaglandin E1 (40μg) induced erection and to evaluate the clinical usefulness of DD scanning in the diagnosis of cavernovenous leakage (CVL). The results of DD scanning and cavernometry were compared in 10 potent control subjects and 82 impotent patients. RI was ≥ 1 in all control subjects later than 10 min after the intracavernous injection and RI at 20 min after the injection (RI20) was chosen as a clinical parameter. An inverse correlation (r = −0.69, p < 0.001) between RI20and the maintenance flow (MF) at 150 mm Hg (MF150) was demonstrated. Sensitivity and specificity of RI20(values <1 indicating CVL) as a test of CVL (MF150> 18 ml/min) were 89% and 86%, respectively. In conclusion, the measurement of RI20in DD scanning after an adequate pharmaco-stimulation is a reliable, noninvasive method in the diagnosis of CVL.
Advanced Multiple Beam Equalization Radiography (AMBER) Combined with Computed Radiography
Authors: de Rooy T. P. W. , Oestmann J. W. , Kool L. J. Schultze , Vrooman H. , Buchmann F.
Published: June 2015

The combined use of AMBER (Advanced Multiple Beam Equalization Radiography) and a digital storage phosphor (SP) radiography system was evaluated for chest radiography in a pilot study with 4 patients. Four image modes with different dose levels were compared: the SP in combination with an AMBER equalized exposure (SP/AMBER) and 3 nonequalized exposures with dose levels corresponding to the respective calculated AMBER lung dose (SP/lung field dose), the calculated AMBER mediastinal dose (SP/mediastinal dose) and the calculated AMBER average dose (SP/average dose). All image modes were matched for Hurter and Driffield characteristics and subjectively rated according to visibility of details. The improved signal-to-noise (S/N) ratio of SP/AMBER resulted in a better visualization of structures in the mediastinum and the basal lung where SP/lung field dose scored lowest. For the central lung no quality differences were seen between techniques. The compressed dynamic range of the SP/AMBER images was more easily displayed on the hard-copy film. The combination of AMBER with SP radiography promises to overcome the dynamic range limitations of digital displays while, at moderate doses, giving better S/N and image quality than standard SP technique.
Normal Left Ventricular Wall Motion Measured with Two-Dimensional Myocardial Tagging
Authors: Qi P. , Thomsen C. , Ståhlberg F. , Henriksen O.
Published: June 2015

Using a myocardial tagging technique, normal left ventricular wall motion was studied in 3 true short axis views and a double oblique 4-chamber view in 14 and 11 volunteers, respectively. Three orthogonal directions of left ventricular motion were observed throughout the systole; a concentric contraction towards the center of the left ventricle, a motion of the base of the heart towards the apex, and a rotation of the left ventricle around its long axis. The direction of left ventricular rotation changed from early systole to late systole. The base and middle levels of the left ventricle rotated counterclockwise (CCW) at early systole and clockwise (CW) at late systole, whereas the apex of the heart rotated CW at early systole and CCW at late systole. The different directions of the rotation of base and apex resulted in a myocardial twisting that changed direction from early to late systole. We conclude that MR imaging with myocardial tagging is a method that can be used to study normal left ventricular wall motion, and that is promising for future use in patient groups.
Sonographic Evaluation of Renal Appearance in 665 Adult Volunteers
Authors: Emamian S. A. , Nielsen M. B. , Pedersen J. F. , Ytte L.
Published: June 2015

The purpose of this study was to investigate the sonographic appearance of the normal adult kidney. Parenchymal echogenicity, pyramid visibility, and transverse pelvis diameter of the kidneys were prospectively determined in an age- and sex-stratified random sample of 665 volunteers 30, 40, 50, 60, and 70 years old. Furthermore, incidences of kidney stones and split sinus echo were determined. The relation between obesity and above-mentioned parameters was evaluated. In the 30-year-old age group the right kidney was isoechoic as compared to the liver in 1/3, and had clearly or faintly visible pyramids in 2/3 of the cases. These rates decreased gradually with increasing age. Transverse diameter of renal pelvis ≥10 mm was observed in 13% of participants. Renal stones were observed in 2.1%. The incidence of split sinus echo was 3.6%. Obese participants showed lower incidences of isoechogenicity, pyramid visibility, pelvic ectasia, and split sinus echo. Isoechoic parenchyma, clearly visible pyramids, and transverse pelvis diameter ≥10 mm are not uncommon sonographic findings in normal adult kidneys and should not be used as indicators of renal pathology.
CT of Retropharyngeal Lymph Node Metastasis from Maxillary Carcinoma
Authors: Watarai J. , Seino Y. , Kobayashi M. , Shindo M. , Kato T.
Published: June 2015

CT findings for retropharyngeal lymph node metastasis in 25 patients with histologically proven carcinoma of the maxillary sinus and with no prior treatment were evaluated retrospectively. Four lateral retropharyngeal node metastses (16%, 4/25) could be identified by CT. All retropharyngeal metastatic nodes were located between the ipsilateral internal carotid artery and the longus colli muscle at the level of the first cervical vertebral body. The metastatic nodes ranged from 8 mm to 35 mm in size at the long axis. The risk of retropharyngeal node metastasis depends on the degree of carcinoma involvement to the posterior nasal cavity, the posterior ethmoid sinuses, the sphenoid sinuses, the palate (soft and hard) and the nasopharynx. This study indicates that CT is useful for detecting these lymph node metastases.
Oral Contrast Media in CT of the Abdomen
Authors: Lönnemark M. , Magnusson A. , Ahlström H.
Published: June 2015

In a double-blind randomized study 3 different preparations of oral contrast media for bowel opacification at CT of the abdomen have been compared. Plain aqueous solutions of amidotrizoate (9 mg I/ml) and iohexol (9 mg I/ml) were used as well as a preparation of iohexol (9 mg I/ml) to which a viscosity-increasing agent had been added. The distribution of the contrast media in the intestine, transit time and patient tolerance were evaluated. No significant differences were found regarding the distribution between the 3 preparations of contrast media, while there was a tendency for the transit time to be increased when the viscous preparation of iohexol was used. The aqueous solution of iohexol had the best taste, while the viscous preparation was markedly more difficult to drink. Aqueous solutions of iohexol and amidotrizoate were equal for bowel opacification and the addition of the viscosity-increasing agent did not improve the distribution of the contrast medium in the intestine.
MR Appearance of Central Neurocytoma
Authors: Chang K. H. , Han M. H. , Kim D. G. , Chi J. G. , Suh D. C. , Kim S. J. , Cha S. H. , Han M. C.
Published: June 2015

To provide a detailed description of the MR appearances of central neurocytoma, MR images of 13 patients with central neurocytoma were retrospectively reviewed and compared with CT examinations. The histology was confirmed by ultrastructural and immunohistochemical studies. In 12 patients the tumors were histologically benign and located in the anterior part of the lateral ventricle, 6 of which extended to the 3rd ventricle. There was one case of a histologically malignant variant involving the thalamus and lateral ventricle. The tumors were primarily solid, but contained cysts (85%, 11/13), calcifications (69%, 9/13), and signal void from tumor vessels (62%, 8/13), frequently producing heterogeneous signal intensity on both T1- and T2-weighted images. Most of the solid portion appeared isointense or slightly hyperintense relative to the cerebral cortex on all MR pulse sequences. Calcifications were iso- or hypointense on MR, making them difficult to characterize with MR alone. Intratumoral hemorrhage was seen in 2 patients on MR but not on CT. Contrast enhancement was variable in degree and pattern. Coronal and sagittal MR images were valuable in evaluating the tumor extent and origin site, and in planning the surgical approach. It is concluded that MR imaging appears to be more useful than CT in the overall evaluation of central neurocytoma, even though calcification is better characterized with CT.
Lumbar Percutaneous Automated Nucleotomy
Authors: Dullerud R. , Amundsen T. , Johansen J. G. , Magnæs B.
Published: June 2015

The purpose of this study was to evaluate 2 years' experience with percutaneous automated nucleotomy. Adult patients with small to medium sized disk hernias corresponding to clinical symptoms, and without evidence of free fragments or stenosis were treated on an outpatient basis. All patients had sciatica and conservative treatment had failed for at least 3 months. Using the Nucleotome R system, access to the disk was achieved in all but 6 of 172 disks in 152 patients. Degenerative disk disease or pain was the reason for technical failures. Four other procedures were discontinued because of pain and moderate hemorrhage. Except for one case of diskitis, no serious complications occurred. Of the patients in a prospective study, 63 had a follow-up period of 4 months or more. The overall clinical success rate was 62%, and was not significantly influenced by patient sex or age, duration of symptoms, level treated, disk degeneration or amount of nucleus material removed. The results are promising; however, this study indicates a need for refined patient selection in order to decrease the number of failures.
CT for Assessment of Pancreatic and Periampullary Cancer
Authors: Andersen H. Bryde , Effersøe H. , Tjalve E. , Burcharth F.
Published: June 2015

Over a period of 2 years, 77 patients, strongly suspected of having pancreatic cancer, had abdominal CT as part of the diagnostic work-up. The CT images were reviewed by 2 radiologists who did not know the clinical course, the surgical procedure, or the final diagnosis. The positive predictive value of CT for the diagnosis of pancreatic cancer was 92% (82–97%) and the negative predictive value 69%) (41–89%). The 95% confidence limits of the positive predictive value of CT in staging the extent of periampullary cancer in 52 patients varied between 21 to 79% and 59 to 100%, with the lowest values in diagnosis of liver metastases. The confidence limits for the negative predictive values in staging varied between 17 to 56% and 67 to 94%, with the highest values concerning liver metastases. We conclude that CT cannot be used as the only diagnostic procedure for confirming or excluding the diagnosis of pancreatic or periampullary cancer, and that the staging of periampullary cancer by CT alone is too inaccurate for the evaluation of resectability.
Radiologic Appearance of Nonpalpable Intramammary Lymph Nodes
Authors: Svane G. , Franzén S.
Published: June 2015

Sixty-four well circumscribed nonpalpable lesions, mammographically evaluated as benign and cytomorphologically verified as lymph nodes, were studied concerning mammographic appearance, size and location within the breast. The great majority, 72%, were situated within the upper-outer quadrant, but lymph nodes were also diagnosed in other areas of the breast. Of the verified lymph nodes 50 (78%) had a lower density at the center than at the periphery. These were the only well circumscribed nodules with a low density center observed in a total of 3 623 nonpalpable lesions stereotaxically needled during the same period. Three of the lymph nodes were verified histopathologically. Till now, none of the other 61 lesions has turned out to be a malignant tumor during a follow-up time from 9 to 15 years. Thus a lesion presenting roentgenologically as a well circumscribed nodule with a central area of decreased density compared to the peripheral part can be confidentially diagnosed as a lymph node by the mammograms alone and no further investigation is indicated.
Cystic Renal Cell Carcinoma
Authors: Yamashita Y. , Watanabe O. , Miyazaki T. , Yamamoto H. , Harada M. , Takahashi M.
Published: June 2015

Twenty-seven cystic renal cell carcinomas (RCC) in 23 patients were analyzed radiologically and histologically. They were classified into 4 histopathologic growth patterns: a) multilocular (n = 15, 9 with macrocystic and 6 with microcystic components); b) unilocular (n = 3); c) cystic necrosis (n = 9); and d) tumors originating in the wall of a simple cyst (n = 0). Macrocystic multilocular RCC showed multiloculated configuration on ultrasound and contrast enhanced CT. Angiography revealed neovascularity peripherally or within the tumor (7/9 tumors). Microcystic multilocular RCC did not fulfill the criterion for a cystic mass on ultrasound: they were irregularly hyperechoic. There was little enhancement on postcontrast CT and only slight neovascularity on angiography. Unilocular RCC showed a cystic mass with an irregular wall or mural nodules on ultrasound and contrast enhanced CT. Necrotic RCC showed various sonographic findings from anechoic to irregular echoic. The appearance on CT varied from cystic with mural nodules to a multiloculated or irregular architecture. Neovascularity was seen in the periphery in 8 of 9 tumors. Clinically, this type seemed to be the most aggressive.
Simultaneous Videoradiography and Computerized Pharyngeal Manometry — Videomanometry
Authors: Olsson R. , Nilsson H. , Ekberg O.
Published: June 2015

To obtain more information about muscle function in patients with dysphagia, simultaneous barium swallow and computerized pharyngeal manometry with solid-state pressure transducers was employed for the evaluation of the pharynx and the pharyngoesophageal segment (PES) in 30 consecutive patients. The manometry catheter was positioned under fluoroscopic control, providing localized measurements of the intraluminal pressures in the pharynx. Sixteen patients had a normal barium swallow. In 5 (31%) of these the manometry disclosed PES dysfunction, i.e. increased resting pressures between swallows in 3 patients (mean 120 ± 13 mm Hg), and increased contraction pressures during peristalsis in 2 (mean 297 ± 21 mm Hg). Barium swallow and manometry are complementary: the former reflecting transport through the pharynx and penetration to the airways, the latter the intraluminal pressures created by the pharyngeal wall. The combination of barium swallow and manometry gives information about pressure in relation to bolus transport, which may elucidate pharyngeal dysfunction.
Posttraumatic Osteolysis of the Pubic Bone Simulating Malignancy
Authors: Albertsen A. M. , Egund N. , Jurik A. G. , Jacobsen E.
Published: June 2015

Posttraumatic osteolysis (PO) of the os pubis is a diagnostic entity characterized at radiography by rapidly progressing destructive changes in fractures of the pubic body or rami. Fourteen patients with PO are here reported of whom in 8 the radiographic course of the condition was followed. They were all post-menopausal women and 7 were predisposed to osteopenia. The primary fractures were related to mild trauma in 7 patients and 7 had insufficiency fractures. Four patients had bilateral symmetrical PO. All 14 patients had concomitant insufficiency fractures of the sacrum observed at radiography, CT, scintigraphy or MR, probably due to pelvic instability caused by the PO of the os pubis. Symptoms of the sacral fractures usually dominated the clinical condition. Bony healing of the PO did not occur in any of the patients, but in all 8 patients followed radiographically, the fractures of the sacrum healed clinically and at CT. Knowledge about the condition is important to avoid unnecessary biopsy of the PO considered a metastatic lesion and/or extensive diagnostic search for a primary tumor.
MR Imaging of Pituitary Region Lesions with Gadodiamide Injection
Authors: Hald J. K. , Skalpe I. O. , Bakke S. J. , Nakstad P. H.
Published: June 2015

Twelve patients with known or suspected pituitary lesions underwent MR imaging with gadodiamide injection at a dose of 0.1 (n = 5) or 0.3 (n = 7) mM/kg. Six of the patients were also studied with 0.1 mM/kg gadopentetate dimeglumine. Consistent with previous reports gadodiamide injection was found to be a safe and effective contrast medium for MR imaging of the pituitary region. No additional diagnostic information was obtained using 0.3 mM/kg gadodiamide injection compared to 0.1 mM/kg gadopentetate dimeglumine in the same patients. The high dose (0.3 mM/kg) gadodiamide injection in 7 patients did not shorten the T2 value sufficiently to overwhelm the T1 shortening and leave pathologic lesions hypointense compared to precontrast studies. With the comparable relaxivities of gadodiamide injection and gadopentetate dimeglumine, similarities in results have to be expected when using these media for MR image enhancement.
Interaction between Beta-Blockers and Contrast Media during Intracoronary Administration in Rabbit Heart
Authors: Salbaş K. , Akgün G. , Pamīr G. , Gürel T.
Published: June 2015

The effects of ionic, meglumine sodium diatrizoate (Urografin 76) and nonionic, iohexol contrast media were examined in the absence and presence of propranolol, a beta-blocker having nonspecific membrane stabilizing action and atenolol, a beta-blocker lacking nonspecific membrane stabilizing action on Langendorff-perfused rabbit hearts. Contrast medium, 0.7 ml, was injected into the aortic root in the absence and presence of 10−7 and 10−5 M beta-blocker to observe the changes in resting tension, force of contraction, rate of contraction, heart rate and PR interval. Beta-blockers and contrast media interact in affecting myocardial contractility, heart rate and atrioventricular conduction. The interaction is milder when the beta-blocker lacks membrane stabilizing activity and the contrast medium is nonionic.
Effect of Iodinated Contrast Media on Ionic Calcium
Authors: Hayakawa K. , Okuno Y. , Fujiwara K. , Shimizu Y.
Published: June 2015

This study was conducted to characterize the alterations in serum ionized calcium induced by contrast media (CM) and to determine the cause of the change. Fresh human blood samples as well as an electrolyte solution (ES) containing 1.2 mM calcium ions were diluted with CM and alterations in ionized calcium were measured using an electrometer. The CM tested were diatrizoate, iopamidol, iohexol, ioxaglate, isotonic saline, Na2-Ca-EDTA and pure meglumine. When CM were mixed with blood, ionic CM produced a greater decrease in ionized calcium than nonionic CM or saline. When mixed with ES, a significant reduction of ionized calcium was induced by ioxaglate and diatrizoate in comparison with saline. Na2-Ca-EDTA and meglumine caused no reduction in ionized calcium. Ioxaglate and diatrizoate caused calcium binding due to anions; binding induced by the latter was more prominent than that by the former. These observations suggest that a nonionic CM is more desirable for coronary arteriography of high-risk patients.
MR Imaging of Cerebrospinal Fluid Dynamics in Health and Disease
Authors: Greitz D. , Hannerz J. , Rähn T. , Bolander H. , Ericsson A.
Published: June 2015

The CSF flows in the aqueduct and at the foramen magnum were examined in 5 patients with communicating hydrocephalus (HC) and in 10 with benign intracranial hypertension (BIH) as well as in 5 healthy volunteers. As compared to normal individuals, the aqueductal flow in HC was about 10 times larger and the cervical flow was half as large. In BIH the CSF flows were not different from those of normal volunteers. The decreased arterial expansion as reflected in the reduced cervical flow in HC may be due to pathologic changes in the arteries and paravascular spaces. The large aqueductal flow in HC reflects a large brain expansion, causing increased transcerebral mantle pressure gradient and ventricular dilatation. In BIH there is a normal brain expansion (aqueductal flow) and consequently no ventricular dilatation. It is argued that BIH be caused by an obstruction on the venous side, as opposed to the vascular alterations in HC, which are on the arterial side.
Quality Assurance of the Bedside Chest Radiography Process
Authors: Pohjonen H. , Bondestam S. , Karp P. , Kinnunen J. , Korhola O. , Sakari P. , Savikurki S. , Honkala T. , Standertskjöld-Nordenstam C.-G.
Published: June 2015

The bedside chest radiography process was analyzed in terms of modern quality management guidelines and the sources of quality problems were identified. In order to analyze systematically the various quality factors, the process was described in a top-down fashion with the aid of data flow diagrams. Two internal quality control points and one external point were found in the process. Means to measure quality at the quality control points including questionnaires and a formula for calculating the internal quality index were developed.
Diagnosis of Diffuse Lung Disease by Cutting Needle Biopsy
Authors: Lohela P. , Tikkakoski T. , Ämmälä K. , Strengell L. , Suramo I. , Repo U. K.
Published: June 2015

The results of 15 consecutive automated cutting needle (1.2 mm, n = 14; 2.0 mm, n = 1) biopsies of diffuse lung manifestations are presented. Sufficient material for histologic analysis was obtained in 13 of 15 specimens (87%) and a specific diagnosis was obtained in 11 of 14 patients (79%). The tissue specimen confirmed the clinically probable lung disease in 6 patients, gave a new, unsuspected, diagnosis in 2, and resolved a differential diagnostic problem in 3 patients. One pneumothorax after a 2.0-mm needle biopsy necessitated catheter drainage. We conclude that percutaneous lung biopsy with the automated biopsy device mounted with a 1.2-mm needle yields a histologic diagnosis with high accuracy in interstitial and alveolar lung changes, reducing the need for more invasive methods such as open lung biopsy.
Evaluation of Spinal Bone Changes in Patients with Chronic Renal Failure by CT and Mr Imaging with Pathologic Correlation
Authors: Ito M. , Ito M. , Hayashi K. , Noguchi M. , Kitamori H.
Published: June 2015

To investigate bone changes in patients with chronic renal failure (CRF), bone mineral density (BMD) and T1 relaxation times were measured with CT and MR imaging and the results were correlated to histology. Excised lumbar vertebrae from 25 autopsy cases of CRF (18 males and 7 females), including 12 cases in which the patients had been receiving hemodialysis were examined. BMD and T1 relaxation time values were associated with specific histologic findings for cellularity, trabeculae, and peritrabecular fibrosis. Three vertebrae with low BMD showed increased hematopoietic marrow content, a finding not observed in primary osteoporosis. The vertebrae with osteosclerosis showed prolonged T1 relaxation time, which was due to increased amount of hematopoietic marrow, and the presence of thickened or many small irregular trabeculae or peritrabecular fibrosis. These findings may be useful in the evaluation of bone changes in patients with CRF.