bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetic Iron Oxide Particles Coated with Carboxydextran for Parenteral Administration and Liver Contrasting
Authors: Lawaczeck R. , Bauer H. , Frenzel T. , Hasegawa M. , Ito Y. , Kito K. , Miwa N. , Tsutsui H. , Vogler H. , Weinmann H.-J.
Published: January 2010

Rationale and objectives: To evaluate the physical and pharmacological profiles of SH U555A, a suspension of magnetic iron oxide particles that is designed to enhance the visualization of liver tumors and metastases.

Material and Methods: Chemical and physical methods were used to characterize the size and structure of these magnetic iron oxide particles in aqueous solution. The biodistribution and pharmacokinetics of the particles were studied in mice, rats and dogs. The imaging efficacy of the particles was demonstrated by MR imaging in rat liver tumors

Results: The SH U555A particles consist of low-molecular-weight carboxydextran-coated iron oxides predominantly of the γ-Fe2O3 form with a hydrodynamic diameter ranging from 57-59 nm and strong T2 relaxivity of 164 liters * mmol−1 * S−1 (water, 0.47 T). In rats the particles exhibited a dose-dependent half-life of between 2 and 3 days in the liver at a dose of 20 μmol Fe/kg and a shorter half-life at lower doses. No major side effects were found. In a rat tumor model the tumor-to-liver contrast was markedly improved after i.v. administration of SH U555A. At a dose of 14 μmol Fe/kg the half-maximal contrast-effect was obtained even in nonoptimized T1-weighted spin-echo images.

Conclusion: SH U555A is a superparamagnetic MR contrast agent for i.v. administration and has substantial potential for the demarcation of liver tumors.
Peak Systolic Velocity, Resistance Index and Pulsatility Index
Authors: Mikkonen R. , Kreula J. M. , Virkkunen P. J.
Published: January 2010

Purpose: To study variation in the process of measuring Doppler ultrasound (US) wave forms.

Material and Methods: Eleven radiologists measured peak systolic velocity (PSV), resistance index (RI), and pulsatility index (PI) from a pre-recorded videotape. The wave forms were taken from the carotid, brachiàl, celiac, and renal interlobar arteries in a healthy volunteer. Each radiologist obtained measurements 10 times from a freely chosen wave form of 10 wave forms (10-beat series) and then a further set of measurements also 10 times from a specific wave form (1-beat series).

Results: There was a significant variation in all the PSV, RI and PI values measured, both in the 1-beat series and in the 10-beat series. The greatest variation was seen in the PI values: up to 5.1-fold. Both intraobserver and interobserver reproducibilities were poor.

Conclusion: The process of obtaining measurements from an identified wave form is a major source of error in Doppler US studies. Special attention should be paid to this final phase of an examination. We recommend that measurements be obtained from more than one heart beat.
Clinical multi-colour fluorescence imaging of malignant tumours - initial experience
Authors: Svanberg K. , Wang I. , Colleen S. , Idvall I. , Ingvar C. , Rydell R. , Jocham D. , Diddens H. , Bown S. , Gregory G. , Montán S. , Andersson-Engels S. , Svanberg S.
Published: January 2010

Purpose: the detection of malignant tumours relies on a variety of diagnostic procedures including X-ray images and, for hollow organs, endoscopy. the purpose of this study was to present a new technique for non-invasive tumour detection based on tissue fluorescence imaging

Material and Methods: A clinically adapted multi-colour fluorescence system was employed in the real-time imaging of malignant tumours of the skin, breast, head and neck region, and urinary bladder. Tumour detection was based on the contrast displayed in fluorescence between normal and malignant tissue, related to the selective uptake of tumour-marking agents, such as haematoporphyrin derivative (HPD) and δ-amino levulinic acid (ALA), and natural chromophore differences between various tissues. in order to demarcate basal cell carcinomas of the skin, ALA was applied topically 4–6 h before the fluorescence investigation. for urinary bladder tumour visualisation (transitional cell carcinoma of different stages including carcinoma in situ), ALA was instilled into the bladder 1–2 h prior to the study. Malignant and premalignant lesions in the head and neck region were imaged after i.v. injection of HPD (Photofrin). Finally, the extent of in situ and invasive carcinomas of the breast was investigated in surgically excised specimens from patients that received a low-dose injection of HPD 24 h prior to the study. the tumour imaging system was coupled to an endoscope. Fluorescence light emission from the tissue surface was induced with 100-nslong optical pulses at 390 nm, generated from a frequency-doubled alexandrite laser. with the use of special image-splitting optics, the tumour fluorescence, intensified in a micro-channel plate, was imaged in 3 selected wavelength bands. These 3 images were processed together to form a new optimised-contrast image of the tumour. This image, updated at a rate of about 3 frames/s, was mixed with a normal colour video image of the tissue

Results: A clear demarcation from normal surrounding tissue was found during in vivo measurements of superficial bladder carcinoma, basal cell carcinoma of the skin, and leukoplakia with dysplasia of the lip, and in in vitro investigations of resected breast cancer

Conclusions: the initial clinical experience of using multi-colour fluorescence imaging has shown that the technique has the potential to reveal malignant tumour tissue, including non-invasive early carcinoma and also precancerous tissue. Further investigations are needed to fully develop the method
Overhauser-enhanced MR imaging (OMRI)
Authors: Golman K. , Leunbach I. , Ardenkjær-Larsen J. H. , Ehnholm G. J. , Wistrand L.-G. , Petersson J. S. , Järvi A. , Vahasalo S.
Published: January 2010

Purpose: to evaluate a new single-electron contrast agent for Overhauser-enhanced MR imaging. the contrast agents that are currently available give enhancement factors that are too low to make the technique a valid option for routine clinical use

Material and Methods: MR images were generated directly following the injection of the substance into rats. the MR scanner was operated at a main magnetic field of 0.01 T and equipped with a separate rf-transmitter tuned to the electron paramagnetic resonance frequency of the contrast agent

Results: as expected, the images generated show a high level of enhancement in areas where the contrast agent was present, and a maximum enhancement of 60 times the normal proton signal was obtained in the vascular area. the signal-to-noise ratios in the images were superior to those previously attained

Conclusion: the new contrast agent makes it possible to generate MR images with both morphological and functional information at 0.01 T. the signal-to-noise ratios found in the generated images were of the same order as, or better than, those obtained with the standard clinical routine
MR abnormalities of the intervertebral disks and adjacent bone marrow as predictors of segmental instability of the lumbar spine
Authors: Bräm J. , Zanetti M. , Min K. , Hodler J.
Published: January 2010

Purpose: to assess whether MR abnormalities of the intervertebral disks and adjacent bone marrow can predict segmental instability of the lumbar spine as diagnosed on functional radiographs

Material and Methods: A consecutive review was made of 60 patients examined with MR imaging and with lateral flexion and extension views of the lumbar spine. Sagittal T1- and T2-weighted images were evaluated blindly with regard to abnormalities of the intervertebral disk and the adjacent bone marrow. Segmental instability was diagnosed when a.p. translation of 3 mm or more was present on the functional radiographs. Moreover, the presence of osteophytes was evaluated on lateral standard radiographs

Results: of a total of 300 segments, 32 (10.7%) were unstable. Anular tears were the most relevant MR finding. Their sensitivity, specificity, and positive and negative predictive values for segmental instability were 18.8%, 97.0%, 42.9% and 90.9%. the corresponding values for traction osteophytes were 12.5%, 98.1%, 44.4% and 90.4%. Abnormalities of bone marrow were not significantly related to segmental instability ( p = 0.35)

Conclusion: Functional radiographs should be considered in patients with anular tears or traction osteophytes. No correlation was found between segmental instability and abnormalities of bone marrow adjacent to the endplates
Joint-space width in the weight-bearing radiogram of the tibiofemoral joint
Authors: Boegård T. , Rudling O. , Petersson I. F. , Jonsson K.
Published: January 2010

Purpose: the aim of the study was to compare the minimal joint-space (MJS) width of the tibiofemoral joint (TFJ) in weight-bearing radiograms with the patient in two different positions

Material and Methods: from a study of 54 patients with chronic knee pain (aged 42–59 years, mean 52 years), we selected 21 consecutive patients for this study. in these 21 patients, both knees were examined by means of p.a. weight-bearing radiograms in semiflexion with fluoroscopic guidance. the patient stood with the weight: 1) almost entirely on the examined leg; and 2) equally distributed on both legs. the MJS was measured with a scale loupe in tenths of a millimeter in the medial and lateral compartments of the TFJ

Results: with the patient standing on one leg, the MJS was 0.18 mm wider (p<0.006) in the medial compartment and 0.18 mm narrower (p<0.029) in the lateral compartment as compared to standing on both legs

Conclusion: with the technique used, the assessment of the MJS width in the p.a. view of the TFJ in weight-bearing examinations should be performed with equal weight on both legs. Standing on only the examined leg might be an option in cases of suspected narrowing in the lateral compartment
Advance in the diagnosis of esophageal carcinoma
Authors: Ueyama T. , Kawamoto K. , Yamada Y. , Yoshikawa H. , Masuda K.
Published: January 2010

Purpose: to assess the clinical utility of computed radiographic images processed with adaptive spatial filtering (ASF) in the diagnosis of esophageal carcinoma

Material and Methods: After determining the optimal values for ASF image parameters in double-contrast barium studies, we used ASF to process the esophagograms of 35 patients with 37 esophageal carcinomas (superficial 20, advanced 17). the image quality of each lesion was evaluated independently by four radiologists on the basis of detectability, extent, and surface structure. the scoring was: 1 when the ASF image was superior to the original; — 1 when the converse was true; and 0 when quality of images was equal

Results: in superficial carcinoma, the mean scores for image quality with regard to detectability, extent, and surface structure were 0.19, 0.48, and 0.31 respectively. in advanced carcinoma, the scores were 0.00, 0.76, and 0.25 respectively

Conclusion: ASF offers an improved image quality which is valuable in the evaluation of esophageal carcinoma, particularly in the detection of superficial carcinomas and in the identification of intraepithelial extension
Familial juvenile nephronophthisis
Authors: Ala-Mello S. , Jääskeläinen J. , Koskimies O.
Published: January 2010

Purpose: To evaluate progressive US changes in the kidneys of patients with familial juvenile nephronophthisis (NPH), an autosomal recessive progressive kidney disease with polyuria, polydipsia, anemia and growth retardation

Material and Methods: The data from 29 US investigations of 5 boys and 2 girls comprised findings relating to kidney size, echogenicity of the kidney parenchyma, visualization of the corticomedullary junction, and the parameters of renal cysts

Results: In the early stages of NPH, when the serum creatinine values were between 134 and 370 μmol/l, the corticomedullary differentiation was weak in 6 patients, the echogenicity of the kidney parenchyma was equal to or greater than that of the liver in 5 patients, and 6 patients had developed renal cysts. the findings became more intensive with the progression of NPH. the size of the kidneys remained normal in 4 patients

Conclusion: Renal US reveals characteristic changes already in the early stages of NPH and should therefore be an important part of the diagnostics of NPH because no specific diagnostic test is as yet available
Helium gas microbubbles
Authors: Nishiharu T. , Yamashita Y. , Arakawa A. , Mitsuzaki K. , Matsukawa T. , Takahashi M.
Published: January 2010

Purpose: To evaluate histological changes and duration of enhancement after the intra-arterial injection of helium gas microbubbles in comparison with conventionally used carbon dioxide (CO2) microbubbles at US

Material and Methods: Four different doses of helium gas microbubbles (0, 0.1, 0.2 and 0.5 ml/kg) mixed with normal saline and own blood were injected into the celiac artery of 8 rabbits. After one week, autopsies were performed on all animals and histological changes in the liver, stomach and spleen were studied on hematoxylin-eosin stains. in addition, VX-2 tumor strains were transplanted into the femoral muscle in 5 other rabbits. Four weeks after transplantation, we catheterized the femoral artery and either CO2 or helium gas microbubbles were injected under US observation. We evaluated the duration of enhancement in the tumors with the two types of microbubbles

Results: On histological evaluation, damage in hepatic cells as well as multiple areas of gastritis in the stomach were seen when a dose of 0.5 ml/kg of helium gas was used. Damage in the liver and stomach was slight at a dose of 0.2 ml/kg. the spleen was not damaged at doses of under 0.5 ml/kg. in the evaluation of tumor enhancement, the duration of enhancement with helium gas microbubbles ranged from 28 to 45 min (average 36 min) while that with CO2 ranged from 4 to 12 min (average 9 min) (p>0.001 at paired t-test)

Conclusion: Intra-arterial injection of helium gas should not exceed 0.2 ml/kg: a dose of 0.5 ml/kg may cause damage to the liver and stomach. the duration of enhancement with helium gas microbubbles is significantly longer than that with CO2 microbubbles
Septic and aseptic post-operative discitis in the lumbar spine — evaluation by MR imaging
Authors: Grane P. , Josephsson A. , Seferlis A. , Tullberg T.
Published: January 2010

Purpose: the aim of this study was to determine whether it was possible to differentiate septic from aseptic post-operative discitis in the lumbar spine by means of MR imaging

Material and Methods: the study was a retrospective evaluation of 12 patients with prior lumbar discectomy and suspected post-operative discitis displaying low-back pain and typical MR findings. Six patients had elevated serum C-reactive protein (CRP) (septic) and 6 had normal CRP (aseptic). We used MR imaging to assess the distribution and degree of changes in the disc, in adjacent bone marrow, and in surrounding soft tissue

Results: of the 6 patients with increased CRP levels, 3 had extensive MR changes typical of septic post-operative discitis: 1 found soon after surgery; 2 found later. the other 3 patients with septic discitis, who were examined in the early post-operative period, showed MR changes similar to those in the 6 patients with aseptic discitis

Conclusion: Suspicion of septic post-operative discitis should be confirmed by MR imaging, serum CRP, and disc puncture. MR imaging is not reliable as the sole method for distinguishing septic from aseptic discitis in the early post-operative stage
MR imaging in chronic achilles tendon disorder
Authors: Movin T. , Kristoffersen-Wiberg M. , Rolf C. , Aspelin P.
Published: January 2010

Objectives: the primary objective was to compare 4 imaging sequences (T1-weighted, T2-weighted, proton density, and T1-weighted with gadolinium contrast agent enhancement) with regard to intratendinous signal abnormality in patients with achillodynia. the secondary objective was to relate the images to the clinical symptoms and histopathological findings

Material and Methods: Twenty patients (16 men, 4 women, median age 40 years) with chronic achillodynia participated in the study. the symptoms prohibited activity and clinical examination revealed swelling and tenderness 1.5–6 cm proximal to the Achilles tendon insertion. of the 20 patients: 5 had bilateral achillodynia, 4 had had previous contralateral Achilles tendon disorder, and 11 had never had symptoms in the contralateral tendon region. These 11 tendons served as controls for comparison

MR imaging was performed on a superconductive 1.5 T unit. Both Achilles tendons were examined (n=40) at the same time, and multiple sagittal and transversal images were obtained. the corresponding sections on these images were visually graded according to both extension and level of MR signal intensity. Tissue was obtained for microscopic examination from the most symptomatic side in all patients (n=20)

Results: T1-weighted images following gadolinium contrast medium enhancement proved to be the best method by which to visualize intratendinous signal abnormality. This sequence revealed signal abnormality in 24/25 symptomatic tendons and in 1/11 control tendons ( p>0.001). Histopathological examination showed an increased noncollagenous extracellular matrix and altered fiber structure in the lesions corresponding to the contrast-enhanced areas

Conclusion: Gadolinium enhancement improved the imaging of intratendinous signal abnormality on T1-weighted images. There was a high level of extracellular glycosaminoglycans, which are highly-fixed negatively-charged macromolecules with extreme water-retaining capacity and which may have contributed to the enhancement by the gadolinium contrast agent
Early esophageal carcinoma
Authors: Ueyama T. , Kawamoto K. , Yamada Y. , Masuda K.
Published: January 2010

Purpose: the aim of this study was to assess the depth of invasion of early esophageal carcinoma (EEC) by means of double-contrast esophagography

Material and Methods: the radiological findings of 46 EECs were retrospectively analyzed for the following factors that might be related to the depth of invasion: in depressed lesions (n=30): maximum size, surface appearance, sharpness of contour, and wall rigidity; and in elevated lesions (n=16): maximum size, height, shape, and wall rigidity. All lesions were surgically or endoscopically resected and the radiological findings were compared with the histological appearance

Results: in depressed lesions, the size of the surface granules correlated very strongly with the depth of invasion (rs=0.8147). in both depressed and elevated lesions, wall rigidity correlated strongly with the depth of invasion (rs=0.7540 and rs=0.6702 respectively). in depressed lesions, sharpness of contour also correlated strongly with the depth of invasion (rs=0.6731). the other factors did not correlate with the depth of invasion

Conclusion: Double-contrast esophagography could provide useful information for assessing the depth of invasion of EECs
Spiral CT during pharmacoangiography with angiotensin II in patients with pancreatic disease
Authors: Kuroda C. , Mihara N. , Hosomi N. , Inoue E. , Fujita M. , Ohigashi H. , Ishikawa O. , Nakaizumi A. , Ishiguro S.
Published: January 2010

Purpose: to compare the diagnostic efficacy of pancreatic pharmacoangiographic CT using angiotensin II with conventional angiographic CT

Material and Methods: Eighteen patients with space-occupying pancreatic disease were examined in this study. Pharmacoangiographic CT was performed with a 1–3-ůg/6-ml solution of angiotensin II injected through a catheter into the celiac artery during spiral CT

Results: in 17 of the 18 (94%) patients, the area of pancreatic parenchymal enhancement was the same or larger at pharmacoangiographic CT than at conventional angiographic CT. the attenuation value of the pancreatic parenchyma was significantly increased at pharmacoangiographic CT ( p=0.0010). Although the attenuation value of tumors was also increased on images obtained after the injection of angiotensin II, the tumor-to-pancreas contrast was significantly greater at pharmacoangiographic CT ( p=0.0479). the mean differences in attenuation between tumor and pancreas at angiographic CT with and without angiotensin II were respectively 182 HU and 115 HU

Conclusion: Pharmacoangiographic CT with angiotensin II proved superior to conventional angiographic CT in the diagnosis of pancreatic disease. We therefore recommend it as a supplementary technique at the angiographic examination of patients with suspected pancreatic tumor
Sensitivity in detection of hypervascular hepatocellular carcinoma by helical ct with intra-arterial injection of contrast medium, and by helical CT and MR imaging with intravenous injection of contrast medium
Authors: Hori M. , Murakami T. , Oi H. , Kim T. , Takahashi S. , Matsushita M. , Tomoda K. , Narumi Y. , Kadowaki K. , Nakamura H.
Published: January 2010

Purpose: to determine the effectiveness of i.a. contrast-enhanced helical CT and of i.v. contrast-enhanced helical CT and MR imaging, in detecting hyper-vascular hepatocellular carcinoma (HCC)

Material and Methods: Fifty patients with 125 hypervascular HCC nodules underwent helical CT both during arterial portography (CTAP) and during hepatic arteriography (CTHA). Helical CT and MR imaging of the entire liver with i.v. administration of contrast medium were also performed. Helical CT images were obtained at 30–33 s (arterial-phase CT) and at 5 min (equilibrium-phase CT) after the initiation of an i.v. bolus injection of contrast medium. After T1- and T2-weighted spin-echo MR imaging, gradient-echo images during breath-holding were obtained prior to and 20 s, 1 min, and 2 min after the bolus administration of 0.1 mmol/kg of gadopentetate dimeglumine (dynamic MR). the sensitivity and positive predictive value of the various techniques were evaluated and compared

Results: in terms of sensitivity for hypervascular HCC nodules of less than 1 cm in diameter, CTAP (90%) and CTHA (88%) were significantly superior to dynamic MR imaging (44%), arterial-phase CT (39%), spin-echo MR imaging (20%), and equilibrium-phase CT (7%) ( p>0.001). However, there was no significant difference in the techniques with regard to the detection of lesions equal to or more than 2 cm in diameter

Conclusion: for detecting small hypervascular HCCs, helical CT with i.a. contrast enhancement is superior to helical CT and MR imaging with i.v. enhancement
Magnetic starch microspheres in the MR imaging of hepatic metastases
Authors: Sundin A. , Wang C. , Ericsson A. , Fahlvik A.-K.
Published: January 2010

Purpose: to evaluate reticular endothelial system-specific magnetic starch microspheres (MSM) as an i.v. contrast agent for MR imaging in a model of experimental liver metastases

Material and Methods: the study comprised 15 nude rats, 7 of which were carrying hepatic metastases from a human colonic cancer. the 15 rats were examined at 0.5 T using a T1-weighted spin-echo (SE) sequence and a gradientecho sequence. the examinations were performed before and 15 min after the administration of accumulated doses of MSM at 0.25–2.5 mg Fe/kg b.w. the images were compared with corresponding serial liver specimens

Results: A loss of liver signal intensity was obtained at all MSM dose levels. No metastases were detected in the pre-contrast images. the optimum detection rate of hepatic metastases was reached with the SE sequence at a dose of 1.0 mg Fe/kg b.w. MSM and the diameters of the smallest lesions depicted were 1 mm. However, in the SE sequence, the measured lesion-to-liver contrast and liver signal damping were highest at the largest dose, indicating a possible image degrading effect of MSM at high doses. Administration of MSM as a short bolus over 30 s resulted in congestion of the liver with dilatation of the hepatic veins. When MSM was instead injected slowly over 5 min, this adverse effect was not seen

Conclusion: the use of MSM dramatically increased the detection of experimental hepatic metastases
Peritoneocele and enterocele
Authors: Bremmer S. , Mellgren A. , Holmström B. , Udén R.
Published: January 2010

Purpose: to study, by means of defaeco-peritoneography, the formation and transformation of the peritoneocele, with and without an enterocele, during rectal evacuation

Material and Methods: Forty-six patients with a peritoneocele at defaeco-peritoneography were selected for the study, and examined at three different stages: 1) at the start with a contrast-filled rectum; 2) at maximum straining; and 3) at rest after rectal evacuation

Results: Fourteen patients had a peritoneocele at the start. These peritoneoceles were largest at maximum straining and were all still present at rest after rectal evacuation. in 32 patients defaeco-peritoneography was regarded as normal at the start. at maximum straining these patients developed a peritoneocele and 20 of these were still present after rectal evacuation. No enterocele was seen at the start. at maximum straining 21 patients developed an enterocele and 15 of these were still present after rectal evacuation. Liquid in varying amounts was found in the peritoneoceles

Conclusion: the present study demonstrated that peritoneoceles were present at different stages of the defaeco-peritoneographic investigations. Peritoneoceles were most frequent and largest at maximum straining. an enterocele was present in half of the peritoneoceles at maximum straining, but never at the start. Liquid was often present in the peritoneoceles
MR features of a 24-year-old gossypiboma
Authors: Roumen R. M. H. , Weerdenburg H. P. G.
Published: January 2010

Retained surgical sponges can cause serious diagnostic problems. We report on our experience with a piece of gauze, encapsulated for 24 years, that mimicked a soft-tissue neoplasm, and we describe its MR features
Treatment of the adverse effects of contrast media
Authors: Thomsen H. S. , Bush W. H.
Published: January 2010

Although low-osmolar contrast media are relatively safe, a moderate nonlife-threatening reaction requiring some treatment does occur in 0.2-0.4% of patients. A severe life-threatening reaction can be expected in 0.04% of patients. Prompt recognition and treatment are invaluable in blunting the adverse response of a patient to radiographic contrast material and may prevent the reaction from becoming severe or even life-threatening. Radiologists and their staff should review treatment protocols regularly so that each can play his/her role efficiently. Knowledge, training, and preparation are crucial for guaranteeing appropriate and effective therapy in the event of an adverse contrast-related event. On the basis of a review of the literature, we suggest a treatment protocol
Three-dimensional spiral CT angiography in the detection of cerebral aneurysm
Authors: Strayle-Batra M. , Skalej M. , Wakhloo A. K. , Ernemann U. , Klier R. , Voigt K.
Published: January 2010

Purpose: The value of CT angiography in the detection and evaluation of aneurysms was compared to digital subtraction angiography (DSA)

Material and Methods: Seventeen patients with acute subarachnoid hemorrhage (SAH) or with known or suspected aneurysm were investigated by means of spiral CT angiography, which included 3D reconstruction. These findings were compared with those at DSA

Results: In 16 patients, 20 aneurysms were found; the remaining patient had an ectatic vessel that simulated an aneurysm. Seventeen of the angiographically proved aneurysms were detected at CT angiography (sensitivity 85%). One further aneurysm was identified retrospectively as the result of greater experience in the method. All the aneurysms that escaped detection at CT were 3 mm in size. All the vessels of the circle of Willis, except for the posterior communicating artery, were properly evaluated at CT angiography. Difficulties were encountered in assessing the posterior communicating artery and the extradural segment of the internal carotid artery owing to their close spatial relationship to the bony structures of the skull base and the cavernous sinus

Conclusion: CT angiography is a low-risk technique with a low level of invasiveness that is useful in following up known aneurysms. The 3D reconstruction yields further topographic information that helps in the planning of endovascular or surgical intervention. The facility for rotating the reconstructed vessels and displaying them from different angles is of particular value in cases difficult to assess at angiography
Optic neuritis
Authors: Elvin A. , Andersson T. , Söderström M.
Published: January 2010

Purpose: To establish the role of Doppler ultrasonography (US) in the examination of patients with acute unilateral optic neuritis

Material and Methods: Twenty-five patients with a clinical diagnosis of optic neuritis were prospectively evaluated and 18 of them were included in the study. The inclusion criteria were MR findings of unilateral disease and age below 50 years. All patients were examined with MR in order to objectively detect, localize and measure the optic nerve lesions and in order to exclude patients with unidentifiable optic nerve involvement. Evaluation with US was performed to determine nerve morphology, nerve swelling, and resistance to flow in the central retinal artery. The patients' contralateral optic nerve served as an internal control. The US findings were correlated to the degree of visual impairment, both initially and at follow-up Visual evoked potential (VEP) assessments were also performed in 16 patients

Results: A statistically significant difference was found in the optic nerve diameter and in the resistance to flow in the central retinal artery between the affected and unaffected eyes. Patients with a prolonged impairment of visual acuity initially had a more swollen nerve and an increased resistance to flow in the affected optic nerve. Prognostic information was also gathered solely by evaluating the unaffected nerve diameter: patients who normally had thinner optic nerves had a more severe form of optic neuritis. VEP assessments were positive in all patients investigated

Conclusion: Doppler US can be used together with a VEP assessment as an indicator of the disease process in acute optic neuritis. These methods offer a potential for monitoring patients over time
Dedicated head-neck coil in MR angiography of the supra-aortic arteries from the aortic arch to the circle of willis
Authors: Strotzer M. , Fellner C. , Fraunhofer S. , Gmeinwieser J. , Albrich H. , Seitz J. , Feuerbach S.
Published: January 2010

Purpose: To evaluate the usefulness of a dedicated head-neck coil in preoperative imaging of the supra-aortic arteries

Material and Methods: Forty consecutive patients with suspected carotid artery stenosis underwent MR angiography (MRA). Using a dedicated head-neck coil, we made a complete evaluation of the supra-aortic arteries and graded the internal carotid artery (ICA) stenoses. MRA was performed at 1.5 T with: coronal 3D FISP from the aortic arch to the circle of Willis; transverse 2D FLASH and 3D TONE of the carotid bifurcation; transverse 3D TONE of the carotid siphon and the circle of Willis; and transverse 3D FISP of the aortic arch. I.a. digital subtraction angiography (DSA) was used as the reference. ICA stenoses of 70% and more at DSA (NASCET methodology) were regarded as severe

Results: Severe ICA stenoses were detected with high sensitivity and specificity: 93% and 92% respectively for coronal 3D FISP; 90% and 85% respectively for transverse 2D FLASH; and 97% and 94% respectively for transverse 3D TONE. The carotid siphon and the intracranial ICA were best depicted by 3D TONE. None of the applied sequences gave a satisfactory visualization of the aortic arch or of the origins of the vertebral arteries

Conclusion: With the head-neck coil, the supra-aortic arteries (including the intracranial vessels) were visualized without the need to reposition the patient, but depiction of the aortic arch was not acceptable. The quantification of ICA stenoses was reliable
Multiplanar and 3d CT of acetabular fractures
Authors: Haveri M. , Junila J. , Suramo I. , Lähde S.
Published: January 2010

Purpose: To establish a standard protocol for the multiplanar (MPR) and 3D shaded surface display (SSD) reconstruction of CT data on acetabular fractures, and to assess the usefulness of these reformats

Material and Methods: Acetabular fractures in 15 patients were imaged by means of plain radiographs, transaxial CT, MPR reformats, and SSD reformats

Results: The classification of the acetabular fracture was revised in 7/15 cases when the transaxial CT images were read after the plain radiographs. Although the MPR and SSD reformats did not alter the classification, they did add to the degree of confidence in the diagnosis in 9/15 cases. In 2 patients, the MPR and SSD reformats indicated operative instead of conservative treatment. In the MPR reformats, the following views were considered essential in all cases: (a) along the anterior column; (b) along the posterior column; and (c) along both columns and the inferior ramus. In the SSD reformats, the following views were considered essential in all cases: (d) the latero-caudal en face view into the acetabulum; and 180° opposite to this, (e) the medio-cranial view (facing the quadrilateral plate). In 10/15 cases, these views were all that was needed for classification. It was, however, essential to remove the femur from the images before reconstructing the SSD views

Conclusion: Complex acetabular fractures with displacement should be evaluated by means of transaxial CT and additional MPR and SSD reformats. The use of appropriate standard MPR and SSD views shortens the time required to produce the reformats and thereby maximizes the benefit gained
The role of CT in the diagnosis of sacro-iliitis
Authors: Geijer M. , Sihlbom H. , Göthlin J. H. , Nordborg E.
Published: January 2010

Objective: Ankylosing spondylitis is a progressive, debilitating disease in which early diagnosis and early treatment can improve the prognosis. Radiographic confirmation is essential for diagnosis but conventional radiography has not proved useful, particularly in the early course of the disease. The aims of this study were to correlate the findings at conventional radiography with those at CT, and to correlate the duration of clinical symptoms with the radiological findings

Material and Methods: Forty patients with clinical sacro-iliitis and 13 controls were evaluated by means of conventional radiography and CT

Results: Conventional radiography was positive in 10/40 patients and CT in 30/40 patients. Conventional radiography was positive in only 2/14 patients with a symptom duration of less than 2 years while CT was positive in 10/14 such patients

Conclusion: The study demonstrated a considerably higher sensitivity in CT than in conventional radiography in detecting the subtle changes necessary for the radiological diagnosis of sacro-iliitis, particularly in cases of short duration. CT allows an early start to be made in treatment with a consequently improved prognosis. The use of conventional radiography cannot be recommended because its low sensitivity delays diagnosis in many instances
MR imaging in shoulder trauma
Authors: Rand T. , Trattnig S. , Haller J. , Nguyen N. K. , Imhof H.
Published: January 2010

Purpose: To determine the adequacy of MR standard protocols by analyzing conventional T1— and T2-weighted SE sequences, and to evaluate the usefulness of additional fat-suppressed (STIR) images in shoulder trauma

Material and Methods: Paracoronal T1-weighted, T2-weighted SE, and STIR images were obtained on a 0.5 T superconductive system in 25 patients with shoulder trauma. In a separate evaluation of T1/T2 images and a combined evaluation of T1/T2 SE- and STIR images, we compared the number of patients with evidence of Hill-Sachs lesions, bone bruises, and/or rotator-cuff lesions

Results: Compared to the combined evaluation of T1/T2 and STIR images, the separate evaluation of T1/T2 SE images revealed identical results for rotator-cuff lesions and Hill-Sachs lesions, but different results for the bone bruises in the area of the major tubercle

Conclusion: Occult fractures of the major tubercle, indicated by areas of bone bruising, might be missed with MR using conventional SE images. We recommend the use of additional paracoronal fat-suppressed sequences in patients with clinically suspected lesions and equivocal findings on plain radiographs and on standard SE sequences
MR findings in tibial adamantinoma
Authors: Judmaier W. , Peer S. , Krejzi T. , Dessl A. , Kühberger R.
Published: January 2010

Adamantinoma of the long bones is a rare skeletal tumor and its MR features have seldom been reported. It is difficult to distinguish from other bone lesions (such as osteofibrous dysplasia or osteosarcoma) by means of conventional radiography and CT. MR imaging, however, may be useful in differentiating adamantinoma from such lesions. With this presentation of a typical case, we hope to draw the attention of radiologists to this lesion and contribute information on its MR appearance
Contrast-enhanced MR imaging as a prognostic indicator of breast cancer
Authors: Boné B. , Aspelin P. , Bronge L. , Veress B.
Published: January 2010

Background: Using contrast-enhanced MR imaging in the diagnosis of breast cancer may provide additional information not only on tumor extension but also on the biological behavior of tumors. Thus certain characteristics such as tumor angiogenesis and the proliferating activity of the tumor, which have been shown to correlate significantly with prognosis, are both potentially amenable to analysis by MR imaging

Material and Methods: We compared contrast enhancement in 50 malignant breast tumors at MR imaging to several prognostic factors, such as tumor size, lymph-node status, histological grade of malignancy, tumor angiogenesis, and proliferating activity as shown by the mitotic count and PCNA immunoreactivity

Results: There was significant correlation between contrast enhancement at MR imaging of breast cancer and both tumor angiogenesis and proliferative cellular activity as shown by PCNA immunoreactivity. Furthermore, there was a correlation between contrast enhancement and tumor malignancy grade as well as tumor invasiveness

Conclusion: These observations suggest that contrast enhancement at MR imaging may be influenced by factors that have prognostic value. If this assumption is correct, contrast-enhanced MR imaging may become a valuable prognostic tool in the pre-operative evaluation of breast cancers
Hepatic parenchymal perfusion abnormalities after pancreaticobiliary surgery
Authors: Mitsuzaki K. , Yamashita Y. , Ogata I. , Nishiharu T. , Urata J. , Takahashi M.
Published: January 2010

Purpose: To evaluate perfusion abnormalities of the liver after pancreaticobiliary surgery

Material and Methods: We retrospectively evaluated 128 patients with pancreaticobiliary malignant tumors who had been examined both before and after surgery by means of helical CT of the liver. An infusion of 3 ml/s of 60% nonionic contrast material was followed by helical CT of the liver in a sequential arterial phase, portal venous phase, and equilibrium phase

Results: of 128 patients, we followed 97. In 21 patients (22%) we found 47 lesions with perfusion abnormalities that were detected 1–33 months (mean 6.6 months) after the operation. All patients were asymptomatic. The shape of each perfusion abnormality was characterized as geographic (n=23, 47%), wedgeshaped (n=21, 45%), or round (n=3, 83.8%). The abnormalities were seen in the arterial phase in 46 lesions (98%), in the portal venous phase in 18 lesions (38%), and in the equilibrium phase in 1 lesion (0.2%). In all lesions, the size either decreased spontaneously, or it remained unchanged for more than one year

Conclusion: Perfusion abnormalities of the liver may occur in patients who undergo pancreaticobiliary surgery. This findings should not be confused with hypervascular metastases
Carcinoma of the uterine cervix
Authors: Abe Y. , Yamashita Y. , Namimoto T. , Takahashi M. , Katabuchi H. , Tanaka N. , Okamura H.
Published: January 2010

Purpose: To compare high-resolution contrast-enhanced (Gd-DTPA) dynamic MR imaging with T2-weighted turbo spin-echo (TSE) imaging in the evaluation of uterine cervical carcinoma

Material and Methods: Thirty-two patients with cervical carcinoma underwent MR imaging on a 1.5 T superconductive unit to have the extension of the disease assessed before treatment. A phased-array coil was used in all patients. In 25 patients, surgical confirmation of the diagnosis was obtained after imaging. Radiation therapy was selected for the remaining 7 patients with advanced carcinoma. Qualitative and quantitative image analyses were also performed

Results: The cervical carcinomas showed maximum contrast in the cervical stroma and myometrium in the early dynamic phase. The tumor/cervical-stroma contrast in the early dynamic phase obtained with the T1-weighted TSE technique (contrast-to-noise ratio 22.6) was significantly higher than that obtained in T2-weighted TSE imaging (contrast-to-noise ratio 4.3). In the evaluation of parametrial invasion, the accuracy of T2-weighted imaging was 71.8% and contrast-enhanced dynamic imaging 81.2%

Conclusion: High-resolution contrast-enhanced (Gd-DTPA) dynamic MR imaging in cervical cancer offers improved tumor/cervical-stroma contrast and provides useful information on parametrial invasion
Krukenberg tumor findings at color and power doppler us; correlation with findings at ct, MR imaging, and pathology
Authors: Cho J. Y. , Seong C. K. , Kim S. H.
Published: January 2010

We report on the findings at color and power Doppler US in 2 cases of Krukenberg tumor. Power Doppler US may suggest a Krukenberg tumor when it shows a relatively prominent vascular signal along the wall of well-demarcated intramural cysts in a solid ovarian mass
Diffusion-weighted MR imaging of acute cerebral ischemia
Authors: Li T. Q. , Chen Z. G. , Hindmarsh T.
Published: January 2010

Diffusion-weighted MR imaging has been used in studies on experimental animal models and on patients with acute cerebral ischemia. Compared with CT and conventional MR techniques, diffusion-weighted imaging can provide earlier and more precise detection of the location and the extent of an ischemic lesion during the critical first few hours after the onset of stroke

Quantitative apparent diffusion coefficient (ADC) mapping of the brain water can also be carried out by recording a series of diffusion-weighted images with different amplitudes of the displacement encoding gradients. ADC maps can provide important information about the extra- and intracellular water homeostasis. ADC reduction of the tissue water is one of the early signals of the pathophysiological cascade resulting from ischemic tissue injury. Diffusion MR imaging has become a valuable tool in stroke research. It may also prove a valuable tool in monitoring the efficiency of therapeutic effects in stroke patients

It is our intention to provide an overview of the recent development in this area with emphasis on the diffusion-weighted MR techniques, and to discuss the possible underlying biophysical mechanisms responsible for the contrast of diffusion-weighted imaging
The effect of paramagnetic contrast media on T1 relaxation times in brain tumors
Authors: Aronen H. J. , Niemi P. , Kwong K. K. , Pardo F. S. , Davis T. L.
Published: January 2010

Purpose: to study T1 relaxation times in brain tumors before and after paramagnetic contrast medium injection

Material and Methods: Seventeen patients with a known or suspected brain tumor were studied with an echo planar inversion recovery imaging sequence using 10 different inversion times. Double injections of Gd chelate (0.1 mmol/kg+0.2 mmol/kg) were administered in 5 patients, and a single 0.2-mmol/kg dose in 12 patients

Results: After the 0.2-mmol/kg dose, T1 decreased from 1121 ± 130 ms to 987 ± 103 ms in gray matter ( p<0.001), and from 666 ± 29 ms to 646 ± 27 ms in white matter ( p<0.001). Tumor T1 shortened from 1515 ± 319 ms to 717 ± 383 ms. After the 0.1-mmol/kg dose (n=5), tumor T1 decreased from 1116 ± 261 ms to 793 ± 202 ms and after the additional 0.2-mmol/kg dose it decreased further to 526 ± 141 ms

Conclusion: Postcontrast T1 relaxation times in tumors showed considerable variation and remained, on average, relatively long compared to white matter. This should be taken into account when deciding which pulse sequences, imaging parameters, and contrast agent doses are optimal for brain tumor imaging
An experimental high-resolution MR coil for the imaging of pathological findings in the post mortem brain stem
Authors: Mäurer J. , Mitrovics T. , Schlecht I. , Knollmann F. , Felix R.
Published: January 2010

Purpose: the purpose of this study was to evaluate the potential of an experimental coil using a whole-body MR unit to delineate pathological changes within formalin-fixed human brain stems

Material, Methods, and Results: the MR images of 9 brain stems were compared with gross anatomy and corresponding histological sections. the resolution of the images was high enough to depict areas of clinically relevant pathological alterations
Detectability of simulated masses and calcifications in mammography
Authors: Olsen J. B. , Skretting A.
Published: January 2010

Purpose: to develop a method for receiver operating characteristics (ROC) studies in mammography

Material and Methods: We developed a phantom based on excised breast tissue and overlay tiles that could be arranged in an arbitrary pattern across the surface of the breast tissue. Some of the tiles contained structures simulating calcifications or masses that produced image contrast near the experimentally determined detection threshold. Based on this phantom, a methodology for performing ROC studies in mammography was developed. the ROC curves were constructed from reporting schemes filled in by radiologists at five different laboratories. the curves were determined by a novel method: a non-linear least-squares fit of a mathematical model to the data

Results: There were large differences among the areas under the ROC curves obtained from the five laboratories
Pleural pneumatocoeles mimicking congenital cystic adenomatoid malformation of the lung
Authors: Aurora P. , McHugh K.
Published: January 2010

We present the plain radiographic and CT appearances of large intrapleural pneumatocoeles in a 13-week-old infant, resulting in compression atelectasis of the left upper and lower lobes, and mimicking congenital cystic adenomatoid malformation
Clinical value of imaging techniques in childhood osteomyelitis
Authors: Kaiser S. , Jorulf H. , Hirsch G.
Published: January 2010

Purpose: the traditional approach to investigating suspected osteomyelitis in children includes conventional radiography and bone scintigraphy. the roles of US, CT and MR imaging are controversial. Our objective was to determine whether the additional use of these modalities would yield information likely to lead to treatment modification

Material and Methods: Sixty-five children with clinically suspected osteomyelitis took part in a prospective study. All patients underwent conventional radiography and bone scintigraphy. in addition to this, US, CT and MR imaging were all performed in 33 patients; the remaining 32 patients were examined with various combinations of these three modalities. the value of the additional information obtained was estimated retrospectively by a pediatric orthopedic surgeon in terms of possible modification of treatment

Results: MR imaging was the modality with the highest sensitivity and specificity for detecting osteomyelitis. MR yielded information likely to influence treatment in the greatest proportion of patients (45%) followed by US (30%)

Conclusion: the standard investigation protocol with the addition of US (because of its ability to detect subperiosteal abscesses early and simply) is adequate in uncomplicated cases. When additional imaging is required to outline a lesion, or in complicated cases, and when bone scintigraphy is inconclusive, MR imaging should also be performed. CT should be considered when MR investigation is not available or when anesthesia is required but cannot be provided