bluuebunny/crossref_metadata_2025 huggingface dataset:
Absorbed dose and image quality in examinations of the colon with digital and analogue techniques
Authors: Persliden J. , Larsson P. , Norén B. , Wirell S.
Published: January 2010

Purpose: Image quality and the absorbed dose to the patient are issues of primary interest in the change-over from the conventional analogue technique to the digital technique in the examination of the colon by means of fluoroscopy. the aim of this study was to compare the incident radiation and to evaluate the image quality in two different X-ray equipment types, one digital and one analogue

Material and Methods: A kerma-area product meter was used to measure the incident radiation to the patient. Both fluoroscopy and total-examination times were measured as was the number of images. an evaluation of image quality was made and statistically analysed

Results and Conclusion: No significant difference in the irradiation dose was observed between the two techniques. the fluoroscopy time was significantly lower with the conventional technique but the total-examination time decreased by 18% with the digital technique. the total number of images taken was higher with the digital technique (25 images compared to 19) owing to the limited field of the image intensifier. Significantly more noise and less sharpness were observed with the digital system but there was no significant difference in contrast or image quality in the various anatomical structures. Although the change-over to the digital system produced a reduction in sharpness and an increase in noise, and no significant dose saving was measured, the digital system was faster to work with and could well be used for diagnostic purposes
Unusual imaging presentations in renal transitional cell carcinoma
Authors: Lee T.-Y. , Ko S.-F. , Wan Y.-L. , Cheng Y.-F. , Yang W.-C. , Hsieh H.-H. , Chen W.-J. , Eng H.-L.
Published: January 2010

Purpose: to report on unusual imaging presentations in renal transitional cell carcinoma (TCC)

Material and Methods: Imaging studies of 140 cases of pathologically proven renal TCC were retrospectively studied with the focus on unusual presentations

Results: Unusual imaging manifestations were found in 20 cases (14.3%). These findings were classified into 5 categories: perirenal abscesses or perirenal hematomas in 6 cases; parenchymal masses in 5; undue thickening of the hydronephrotic wall in 4; “tuberculoid” pyelograms in 3; and tumors with massive necrosis in 2

Conclusion: Deceptive imaging presentations may occur in renal TCC. Recognition of these presentations may help to prevent delay in diagnosis
Recurrent varicocele
Authors: von Heijne A.
Published: January 2010

This is a report on an initial experience with Gd-enhanced 3D phase-contrast MR angiography in 4 patients with recurrent varicocele. the examinations were performed with the patients prone, and a coronal imaging volume was used. the scrotal part of the varicocele was demonstrated in 3 cases and the spermatic vein in 2 cases. This technique could be an alternative to spermatic venography in the radiological mapping of dilated spermatic veins
Pelvic pain syndrome caused by ovarian varices
Authors: Tarazov P. G. , Prozorovskij K. V. , Ryzhkov V. K.
Published: January 2010

Purpose: the aim of this study was to evaluate the clinical effect of therapeutic embolization in the pelvic congestion syndrome caused by ovarian varices

Material and Methods: Six women, aged 25–40 years, with pelvic pain syndrome and marked left (n=5) or bilateral (n=1) ovarian varicocele were treated by transcatheter retrograde venous embolization

Results: the pelvic pain syndrome disappeared in all patients within 4 weeks, and there was regression of the periodic pain in 2 women with dysmenorrhoea. the patients were free of symptoms during the 1–4-year follow-up

Conclusion: Marked ovarian varices may cause a pelvic pain syndrome. Percutaneous embolization improves both the chronic pain and the dysmenorrhea in these patients. Transcatheter treatment could be considered as an alternative to surgical or laparoscopic ligation in ovarian varicocele
Resistive index of the intrascrotal artery in scrotal inflammatory disease
Authors: Jee W.-H. , Choe B.-Y. , Byun J.-Y. , Shinn K.-S. , Hwang T.-K.
Published: January 2010

Purpose: to investigate the utility of the resistive indices (RIs) of the epididymal and intratesticular arteries, and to establish diagnostic criteria for scrotal inflammatory disease on the basis of quantitative color Doppler sonography

Material and Methods: We prospectively examined 29 consecutive patients with scrotal pain, and 15 normal control subjects. the RIs of the intratesticular and epididymal arteries were obtained from color Doppler sonographs

Results: the RIs of the testicular artery in epididymoorchitis were significantly lower than those in normal control subjects and in epididymitis (p<0.01) while the RIs of the testicular artery in epididymitis and control subjects were similar (p>0.5). with a cut-off value of RI=0.5, sensitivity, specificity, accuracy, and positive and negative predictive values were 91%, 94%, 94%, 83%, and 77% respectively. the mean RI of the epididymal arteries in epididymitis and epididymoorchitis was 0.49±0.11. A high level of diagnostic accuracy in scrotal inflammatory disease was achieved when the RIs of the intratesticular and epididymal arteries were less than 0.5 and 0.7 respectively

Conclusion: the RI of the intrascrotal artery would give a more objective evaluation than subjective assessment and could provide diagnostic criteria for scrotal inflammatory disease
Mr-guided joint puncture and real-time mr-assisted contrast media application
Authors: Trattnig S. , Breitenseher M. , Pretterklieber M. , Kontaxis G. , Rand T. , Helbich T. , Imhof H.
Published: January 2010

Objective: to develop, in MR arthrography of the shoulder joint, an MR-guided technique for localizing the needle puncture and confirming the intracapsular needle-tip position by visualization of the contrast media inflow

Material and Methods: Three unfixed human shoulder specimens were examined on a 1.0 T MR unit. on the basis of MR-compatible markers, the optimal entrance point for puncturing the joint was determined. the precise localization of the needle tip (MR-compatible 0.7-mm needle) in the shoulder joint was determined with rapid localizer GRE sequences in 2 orthogonal planes. to confirm the intracapsular position of the needle tip, diluted Gd-DTPA was applied via a long connecting tube and contrast medium inflow into the joint space was controlled on an LCD screen in real-time MR imaging (local-look technique)

Results: MR-compatible markers on the skin allowed the rapid determination of the optimal entrance point for needle puncture. an adequate localization of the intra-articular needle-tip position was possible in all specimens although significant artifacts were present on rapid localizer GRE sequences which resulted in an increase in the apparent width of the needle shaft. Real-time MR imaging of the contrast medium inflow was made possible by the local-look technique and LCD screen on the MR unit and this allowed confirmation of the intracapsular position

Conclusion: in MR arthrography of the shoulder, an MR-guided technique in conjunction with the LCD screen and real-time MR imaging would seem to be a practical alternative to conventional fluoroscopic guidance
MR imaging of the wrist in carpal tunnel syndrome
Authors: Bak L. , Bak S. , Gaster P. , Mathiesen F. , Ellemann K. , Bertheussen K. , Zeeberg I.
Published: January 2010

Purpose: to determine whether specific parameters measured on MR images correlated to electrophysiological changes in carpal tunnel syndrome (CTS)

Material and Methods: Prospective clinical examinations were made of 20 patients with suspected CTS. We performed bilateral electrophysiological examinations of the median nerve and bilateral MR imaging of the wrists

Results: the electrophysiological examination suggested median nerve entrapment in 18 wrists. These wrists were compared to the remaining 22 electrophysiologically normal wrists. in addition, we compared both wrists in 12 patients with unilateral symptoms of CTS without reference to the electrophysiological findings. We found no difference in specific MR parameters between the 2 groups

Conclusion: Neither symptoms nor electrophysiological findings in CTS were related to specific MR parameters
Postero-anterior radiogram of the knee in weight-bearing and semiflexion
Authors: Boegård T. , Rudling O. , Petersson I. F. , Sanfridsson J. , Saxne T. , Svensson B. , Jonsson K.
Published: January 2010

Purpose: the purpose was four-fold: to assess the reproducibility of p.a. weight-bearing radiograms of the knee and the minimal joint-space (MJS) width measurements in these radiograms; to compare the MJS with MR-detected cartilage defects; to evaluate the location of these cartilage defects; and to estimate the relation between meniscal abnormalities and joint-space narrowing

Material and Methods: Fifty-nine individuals, aged 41–58 years (mean 50), with chronic knee pain were examined by means of p.a. weight-bearing radiograms in semi-flexion with fluoroscopic guidance of the knee joint. the MJS was measured with a standard ruler. on the same day MR imaging was performed with proton-density- and T2-weighted turbo spin-echo on a 1.0 T imager. Meniscal abnormalities and cartilage defects in the tibiofemoral joint (TFJ) were noted

Results and Conclusion: the p.a. view of the knee and the MJS measurements were reproducible. MJS of 3 mm is a limit in diagnosing joint-space narrowing in knees with MR-detected cartilage defects. There was a high proportion <p<0.001) of meniscal abnormality within the narrowed compartments in comparison with those that were not narrowed. A larger number of the cartilage defects (p<0.05) was found in the medial femoral condyle than in any of the other condyles of the TFJ. the defects had a dorsal location <p<0.001) as shown in the weight-bearing radiograms of the knee in semiflexion
Magnetization transfer and spin lock MR imaging of patellar cartilage degeneration at 0.1 t
Authors: Koskinen S. K. , Ylä-Outinen H. , Aho H. J. , Komu M. E. S.
Published: January 2010

Purpose: to investigate magnetization transfer (MT) parameters and rotating frame relaxation time T1ρ in patellar cartilage at different levels of degeneration

Material and Methods: Thirty cadaveric patellae were examined at 0.1 T using the time-dependent saturation-transfer MT technique and the spin lock (SL) technique. in an SL experiment, nuclear spins are locked with a radiofrequency (RF) field, and the locked nuclear magnetization relaxes along the magnetic component of the locking RF field. the specimens were divided into three groups according to the level of cartilage degeneration. MT parameters and T1ρ were measured

Results: the MT effect was greater in degenerated cartilage than in normal cartilage. T1ρ was longer in advanced cartilage degeneration than in intermediate cartilage degeneration

Conclusion: the results suggest that more studies are needed to fully establish the value of SL imaging in cartilage degeneration
Combinations of nonlabeled, 125I-Labeled, and Anti-Idiotypic Antiplacental Alkaline Phosphatase Monoclonal Antibodies at Experimental Radioimmunotargeting
Authors: Norrlund R. Rossi , Holback D. , Johansson L. , Hietala S.-O. , Åhlström K. Riklund
Published: January 2010

Purpose: Placental alkaline phosphatase (PLAP) is a membrane-bound oncofetal antigen that can be used for radioimmunotargeting. Preinjection of nonlabeled monoclonal anti-PLAP antibody (H7) and postinjection of monoclonal anti-idiotypic anti-PLAP antibody (αPH7) were used in order to improve the localization efficacy of 125I-labeled H7

Material and Methods: A human cervix adenocarcinoma cell line (HeLa Hep 2) was inoculated subcutaneously in 24 nude mice. Repeated quantitative radioimmunoscintigraphic recordings were performed on 27 occasions in each of the 24 mice during the observation period which lasted for nearly 3 months. the tumor and nontumor doses were calculated according to the Medical International Radiation Dose Committee formula on the basis of the scintigraphic data

Results: All tumors were clearly visualized as early as one day after injection of 125I-labeled H7. the remaining radioactivity was exclusively located in the tumors at days 30–81. as much as 12–16% of the injected dose/g accumulated in the tumors during the first 2 days after injection, and remained stable at this high level for approximately 10 days in all investigated groups. Radioactivity in the whole body was rapidly eliminated during the same time period. the highest tumor/nontumor dose ratio was obtained after a single injection of 125I-labeled H7

Conclusion: Neither a preinjection of nonlabeled H7 nor a postinjection of αPH7 nor a combination of both strategies resulted in improved tumor/nontumor dose ratios compared to a single injection of labeled H7. the monoclonal antibody H7 has a rapid and high uptake, combined with a prolonged retention time in the tumors. the kinetic properties of H7 are different from antibodies targeting intracellular tumor antigens
Diagnostic efficacy of MnDPDP in MR imaging of the liver
Authors: Wang C. , Ahlström H. , Ekholm S. , Fagertun H. , Hellström M. , Hemmingsson A. , Holtås S. , Isberg B. , Jonnson E. , Lönnemark-Magnusson M. , McGill S. , Wallengren N.-O. , Westman L.
Published: January 2010

Purpose: To assess the diagnostic efficacy, safety and tolerability of mangafodipir trisodium (MnDPDP, Teslascan) in MR imaging of the liver.

Material and Methods: Eighty-two patients from 4 centres underwent MR imaging with pre-contrast sequences including T1-weighted SE and GRE, and T2-weighted turbo SE sequences. MnDPDP at a dose of 5 μmol/kg b.w. was administered by slow i.v. infusion, and 20–60 min after infusion the T1-weighted SE and GRE sequences were repeated. Diagnostic efficacy was evaluated by counting the number of lesions and by evaluating whether more information for lesion characterisation was available in post-contrast images. Safety and tolerability were assessed by recording adverse events and infusion-related discomfort.

Results: Significantly more lesions were found in MnDPDP-enhanced T1-weighted SE and GRE images than in unenhanced images of the same sequences. More lesions were also found in these images compared with T2-weighted images at a level of marginal significance. More information was obtained from MnDPDP-enhanced images in 40 cases. Mild to moderate adverse events were experienced by 17% of the patients.

Conclusion: MnDPDP-enhanced images can improve lesion detection in the liver and are helpful for lesion characterisation. To obtain optimal diagnostic information of liver lesions T2-weighted images are also valuable. MnDPDP is a safe contrast agent for MR imaging of liver lesions.
Tumoural portal vein thrombosis
Authors: Marti-Bonmati L. , Lonjedo E. , Mathieu D. , Coffin C. , Poyatos C. , Anglade M. C.
Published: January 2010

Purpose: Intrahepatic thrombus is usually associated with either cirrhosis or hepato-cellular carcinoma (HCC). Most HCCs enhance after the administration of MnDPDP (Teslascan). Our objective was to analyze the enhancement characteristics of tumour portal vein thrombi.

Material and Methods: Thrombi affecting the main or segmental portal veins (17 cases) and the suprahepatic inferior vena cava (1 case) were retrospectively selected from a series of 128 patients studied with MR imaging before and after the administration of MnDPDP. Enhancement was assessed qualitatively and quantitatively.

Results: All tumour thrombi enhanced after MnDPDP administration. The enhancement was more conspicuous in the GRE images. On the quantitative evaluation, the portal thrombus enhancement was greater for GRE images than SE images. Portal thrombi enhanced more than the liver and the HCCs. There was a significant difference between the enhancement of the HCCs and the thrombi with both MR imaging techniques.

Conclusion: The greater enhancement of the tumour thrombus associated with the liver and HCC may suggest that other mechanisms, apart from accumulation of the contrast medium within the hepatocytes inside the thrombi, are involved in thrombus enhancement.
Overview of MnDPDP as a pancreas-specific contrast agent for MR imaging
Authors: Ahlström H. , Gehl H.-B.
Published: January 2010

Purpose: To describe and discuss previous and ongoing clinical and experimental studies with MnDPDP (Teslascan) as a pancreas-specific contrast agent for MR imaging.

Material and Methods: All results, both experimental and clinical, applying MnDPDP as a pancreas-specific contrast agent for MR imaging, were collected.

Results: An increase of up to 100% in signal intensity was seen in normal pancreatic parenchyma, reaching its maximum approximately 25 min after the beginning of MnDPDP administration. Maximal enhancement was sustained for 4 h. Enhancement was only seen in the T1-weighted images. No enhancement was observed in tumours and an increase in contrast-to-noise of about 200% was obtained. The uptake of MnDPDP in pancreatitis compared with normal pancreatic parenchyma was decreased in an animal model.

Conclusion: Improved depiction and demarcation of pancreatic tumours with MR imaging were obtained after administration of MnDPDP. MR imaging with and without MnDPDP might be valuable for staging of pancreatitis.
MR imaging properties and pharmacokinetics of MnDPDP in healthy volunteers
Authors: Wang C. , Gordon P. B. , Hustvedt S. O. , Grant D. , Sterud A. Tufte , Martinsen I. , Ahlström H. , Hemmingsson A.
Published: January 2010

Purpose: Thirteen male volunteers were studied to evaluate the MR imaging properties and pharmacokinetics of 10 mM mangafodipir trisodium infusion (MnDPDP, Teslascan).

Material and Methods: Doses of 5 and 10 μmol/kg b.w. were administered by bolus injection (<1 min) to 5 subjects, and by infusion (20 min) to 8 subjects, with a 3-week wash-out between doses. Infusion subjects underwent MR imaging.

Results: At 1 h after infusion, the plasma concentration of Mn was reduced to ∼15% of the maximum value. Fifteen to 20% of Mn was recovered in the urine, and 50–60% was recovered in the faeces. The rapid initial plasma clearance of Mn is consistent with both rapid tissue uptake and rapid renal elimination. Increases in signal intensity were apparent on T1-weighted images of the liver, pancreas, spleen, renal cortex and the renal medulla, but not in regions of the brain protected by an intact blood-brain barrier. Increases were seen in the choroid plexus and pituitary. Contrast-related adverse events, only flushing of moderate intensity, occurred in bolus injection subjects.

Conclusion: At 5 and 10 μmol/kg, mangafodipir produces relatively long-lasting enhancement of several abdominal organs, including the liver, pancreas and kidney.
Metabolism and pharmacokinetics of MnDPDP in man
Authors: Toft K. G. , Hustvedt S. O. , Grant D. , Martinsen I. , Gordon P. B. , Friisk G. A. , Korsmo Å. J. , Skotland T.
Published: January 2010

Purpose: To study the metabolism and pharmacokinetics of mangafodipir trisodium injection, 0.01 mmol/ml (Teslascan), in healthy male volunteers.

Material and Methods: Eight volunteers received mangafodipir trisodium as an infusion over 20 min, and 5 received it as an injection (≤ min). Both groups received 5 and 10 μmol/kg b.w. with a wash-out period of 3 weeks between doses. Metabolites were measured in plasma, total manganese and zinc were measured in plasma and urine and total manganese was measured in faeces.

Results: The parent compound MnDPDP (manganese dipyridoxyl diphosphate) and 5 metabolites; MnDPMP (manganese dipyridoxyl monophosphate), MnPLED (manganese dipyridoxyl ethylenediamine) and the corresponding zinc compounds ZnDPDP, ZnDPMP and ZnPLED, were detected in plasma. ZnPLED was the only detectable metabolite 8 h after dosing. The apparent volume of distribution of manganese exceeded the interstitial body fluids. The volume of distribution of the ligand indicated distribution to the extracellular fluid only, with the plasma clearance close to the glomerular filtration rate. The manganese was incompletely excreted during the 4 days after treatment with the major part in faeces and less than 20% of the dose in the urine.

Conclusion: Dephosphorylation and simultaneous transmetallation with zinc are the main metabolic pathways of MnDPDP in man.
Plasma pharmacokinetics, tissue distribution and excretion of MnDPDP in the rat and dog after intravenous administration
Authors: Hustvedt S. O. , Grant D. , Southon T. E. , Zech K.
Published: January 2010

Purpose: To investigate distribution and excretion of mangafodipir (MnDPDP, Teslascan) in the rat and dog.

Material and Methods: Formulations of either 14C-MnDPDP or 54MnDPDP were injected intravenously at near clinical doses in rats and dogs.

Results: The manganese (Mn) moiety is rapidly removed from plasma with an elimination half-life of less than 25 min in both species, reflecting a rapid distribution to the tissues and an early excretion. The plasma clearance of the DPDP moiety is slower than that of Mn and it appears to distribute into the extracellular fluid. Mn is distributed largely to the liver, pancreas and kidneys, and in pregnant rats, also to foetal liver and bones. No transplacental passage of DPDP could be detected. The metal is mainly excreted by the faecal route, with a small fraction eliminated early in the urine. DPDP is rapidly and essentially completely excreted in the urine, consistent with the glomerular filtration rate.

Conclusion: The ligand does not appear to facilitate the transport of Mn into any organ except the kidney for subsequent excretion, and it reduces distribution to the heart. The Mn is taken up by those organs indicated for MR imaging, primarily liver and pan-creas.
Comparison of manganese biodistribution and MR contrast enhancement in rats after intravenous injection of MnDPDP and MnCl2
Authors: Ni Y. , Petré C. , Bosmans H. , Miao Y. , Grant D. , Baert A. L. , Marchal G.
Published: January 2010

Purpose: To compare the time course of the MR enhancing properties and biodistri-bution of manganese (Mn) in rats given i.v. Mn dipyridoxyl diphosphate (MnDPDP) or Mn chloride (MnCl2).

Material and Methods: Twenty-four adult rats were injected i.v. with 5 μmol/kg MnDPDP or MnCl2, or with 0.5 ml/kg saline. High resolution T1-weighted MR imaging was performed during early (10 min), mid (2 h) and late (24 h) phases after injection. Mn concentrations in major organs were measured by using an ICP-AES technique, and correlated with MR findings.

Results: Variable degrees of signal enhancement of major organs observed in MR images corresponded with the amount of Mn uptake after injection of MnDPDP or MnCl2. A prominently lower cardiac, pancreatic and hepatic uptake of Mn was seen at 10 min in rats injected with MnDPDP compared with those given MnCl2 and this was reflected in a difference in signal intensity (SI) in the MR images. At 2 h, the Mn content and SI in the major organs were similar with both MnDPDP and MnCl2. An overall Mn clearance was achieved at 24 h without any important organ retention, with kidney excretion of Mn seen only with MnDPDP.

Conclusion: With both MnDPDP and MnCl2, the Mn uptake correlates with the SI enhancement in tissues. The reduced initial cardiac uptake of Mn after MnDPDP treatment compared to MnCl2 may account for the favourable cardiovascular safety of the contrast agent. These data contribute to an understanding of SI enhancement by MnDPDP, and are consistent with other studies showing that at a dose of 5 μmol/kg, MnDPDP can be safely used as a potent MR organ-specific contrast agent.
Clinical implications of studies with MnDPDP in animal models of hepatic abnormalities
Authors: Ni Y. , Marchal G.
Published: January 2010

Mangafodipir trisodium (manganese dipyridoxal diphosphate or MnDPDP) has been introduced as a hepatobiliary MR contrast agent (Teslascan). Its potential to assist in the characterisation of focal liver lesions, the diagnosis of local and global obstructive cholestasis and the evaluation of hepatic function in diffuse liver diseases has been explored in multiple pre-clinical experiments with appropriate animal models. The prompt negative contrast enhancement and delayed peritumoural rim-enhancement seen after i.v. injection of MnDPDP are 2 typical features of primary and secondary liver tumours with high malignancy, while the persistent positive enhancement is a sign of liver tumours of well preserved hepatocytic nature. Liver with local and total biliary obstruction can be visualized in MnDPDP-enhanced MR images as a region with prolonged signal enhancement. This agent could also be used to non-invasively evaluate diffuse liver diseases of different causes.

In the present paper, we review the experimental data in the literature, provide some unpublished results and discuss the potential impact on the clinical use of MnDPDP in the liver. We conclude that MnDPDP is a promising MR liver contrast agent for the detection and characterisation of focal and diffuse liver diseases.
Cardiovascular safety of MnDPDP and MnCl2
Authors: Jynge P. , Brurok H. , Asplund A. , Towart R. , Refsum H. , Karlsson J. O. G.
Published: January 2010

Purpose: To investigate the apparent discrepancy between expected basic physiological responses at the cellular level and the in vivo behaviour of both MnDPDP and MnCl2 adminstered i.v. prompted parallel investigations of these substances.

Material and Methods: Studies were performed in isolated perfused rat hearts, isolated bovine mesenteric arteries, conscious dogs, and dogs with acute ischaemic heart failure.

Results: These studies confirmed that Mn++ at high concentrations acted as a calcium antagonist inducing negative inotropy. Mn++ at low concentrations was an effective su-peroxide scavenger, conserving nitric oxide and facilitating vasodilation. Mn++ maintained or elevated heart rate (HR) and blood pressure (BP), and did not worsen existing cardiac failure. MnDPDP was about 10 times less potent than MnCl2 in eliciting these cardiovascular responses.

Conclusion: The ex vivo properties of Mn++, inducing vasodilation and negative inotropy, are counter-balanced in vivo through the action of 2 mechanisms: extensive plasma protein binding reducing active M++, and the release of catecholamines which maintain or even raise HR and BP. Taken together with pharmacokinetic factors, including maximal plasma concentrations in humans given the recommended 5 μmol/kg dose, it is concluded that MnDPDP in normal clinical use represents no safety risk to the cardiovascular system.
Cardiovascular effects of MnDPDP and mncl2 in Dogs with Acute Ischaemic Heart Failured
Authors: Karlsson J. O.G. , Mortensen E. , Pedersen H. K. , Sager G. , Refsum H.
Published: January 2010

Purpose: To examine the cardiovascular effects of MnDPDP in a model of acute heart failure in the dog, and to compare these effects with those of MnCl2.

Material and Methods: The study involved slow i.v. infusion of either 10,60 and 300 μmol/kg of MnDPDP, or 1, 6 and 30 μmol/kg MnCl2, in increasing doses to groups of 5 dogs. Acute ischaemic heart failure was first induced by injection of polystyrene microspheres (50 ± 10 μm) into the left coronary artery until a stable left ventricular end-diastolic pressure of approximately 20 mm Hg was achieved. The following test parameters were measured: left ventricular end-diastolic pressure; the first derivatives of maximum rate of left ventricular contraction and relaxation; mean aortic pressure; pulmonary artery pressure; right atrial pressure; cardiac ouput; heart rate; QT-time; PQ-time; QRS-width; and plasma catecholamines.

Results: Slow infusion of MnDPDP at doses up to and including 12 times the clinical dose was well tolerated in dogs without further depression of cardiovascular function during acute ischaemic heart failure. At 300 μmol/kg, i.e. 60 times the human dose, only minor haemodynamic and electrophysiological effects were seen, and these were similar to those seen after administration of 30 μmol/kg MnCl2.

Conclusion: The present study suggests that slow infusion of MnDPDP should not cause further deteroriation of cardiac function in patients with heart failure.
General toxicology of MnDPDP
Authors: Larsen L. E. , Grant D.
Published: January 2010

Purpose: To investigate the general toxicology of mangafodipir trisodium (MnDPDP, Teslascan).

Material and Methods: Studies were performed in accordance with standard methods and in compliance with regulations current at the time of conduct.

Results: Single-dose studies in rodents and dogs showed that MnDPDP was tolerated at doses of approximately 2000 μmol/kg, approximately 400 times a single imaging dose of 5 μmol/kg. The single dose tolerance of MnDPDP was approximately 10 times greater than MnCl2. A good safety profile of MnDPDP was also shown in repeat-dose studies (3 weeks), in which the no-observed-adverse-effect level for the rat, monkey and dog was 116, 29 and 10 μmol/kg, respectively. The local tolerance studies indicated that no adverse local tissue reactions are likely to occur after i.v. injection. Other studies indicate that accidental spillage of MnDPDP onto the skin is not expected to lead to significant systemic exposure, or to local irritation or hypersensitivity. MnDPDP was not genotoxic in a battery of several different tests.

Conclusion: MnDPDP was shown to have a good safety profile suitable as an hepatobiliary MR contrast agent for i.v. administration.
Physicochemical characterisation of mangafodipir trisodium
Authors: Tirkkonen B. , Aukrust A. , Couture E. , Grace D. , Haile Y. , Holm K. M. , Hope H. , Larsen Å. , Lunde H. Sivertsen , Sjøgren C. E.
Published: January 2010

Purpose: To determine the structure and various physicochemical properties of man-gafodipir (MnDPDP) trisodium, the active ingredient of Teslascan, a new organ-specific contrast medium for MR imaging.

Material and Methods: The structure of MnDPDP trisodium crystals was determined by X-ray crystallography. The possible existence of polymorphism in MnDPDP trisodium was evaluated by powder X-ray diffraction, optical microscopy, thermal analysis and IR spectroscopy. In addition, various spectroscopic techniques and physicochemical measurements were used for characterisation of MnDPDP trisodium.

Results: The crystallographic data obtained for MnDPDP trisodium show that the general core structure of the MnDPDP anion is similar to that seen in related substances. The metal coordination geometry is a distorted octahedron defined by 2 phenolate oxygens, 2 carboxylate oxygens and 2 amine nitrogens. The unit cell contains 2 MnDPDP anions, 6 sodium ions and 50 water molecules. The various spectroscopic data are consistent with the structure determined by X-ray crystallography. The product (Teslascan) has low viscosity, is isotonic with blood and has a physiological pH.

Conclusion: MnDPDP trisodium is a crystalline, hygroscopic solid which is readily soluble in water. No evidence of polymorphism was seen in the samples studied.
Cerebral CT angiography in the diagnosis of acute subarachnoid hemorrhage
Authors: Lenhart M. , Bretschneider T. , Gmeinwieser J. , Ullrich O.-W. , Schlaier J. , Feuerbach S.
Published: January 2010

Purpose: To evaluate the usefulness of CT angiography (CTA) in the detection of intracranial aneurysms in patients with acute subarachnoid hemorrhage (SAH).

Material and Methods: In 53 patients with nontraumatic SAH a helical contrast-enhanced CTA was performed. CTA data were reconstructed with maximum intensity projection (MIP). Each patient underwent selective arteriography of the cerebral vessels (as the gold standard). CTA (axial images and MIP reconstructions) and arteriography were evaluated separately and their diagnostic information was compared.

Results: In 14 of the 53 patients neither CTA nor angiography showed a vascular malformation. In the remaining 39 patients, angiography demonstrated a total of 51 aneurysms ranging in size from 3 mm to 16 mm. CTA missed one of these aneurysms, which was located at the internal carotid artery. 3-D CT reconstruction was slightly superior to arteriography in the demonstration of the neck, shape and direction of the aneurysms. Partial thrombosis of 3 aneurysms was demonstrated only by CTA.

Conclusion: Although CTA cannot replace cerebral arteriography in the diagnostic work-up of acute SAH, it proved to be helpful in demonstrating the topographic anatomy of cerebral aneurysms and surrounding structures.
MR imaging in squamous cell carcinoma of the head and neck with no palpable lymph nodes
Authors: Yucel T. , Saatci I. , Sennaroglu L. , Cekirge S. , Aydingoz U. , Kaya S.
Published: January 2010

Purpose: To assess the efficacy of MR imaging in the detection of lymph node metastasis in patients with no palpable lymph nodes (“N0 neck”) who have squamous cell carcinoma of the head and neck region.

Material and Methods: MR neck imagings in 18 patients who underwent neck dissection (bilaterally in 2) for squamous cell carcinoma of the head and neck region were examined preoperatively for the purpose of detecting lymph node metastases. The imaging features taken into consideration were: size (cutoff point 10 mm), grouping, presence of central necrosis, and appearance of extracapsular spread. The MR examinations comprised spin-echo T1- and T2-weighted sequences. The MR findings were compared with those of surgery and histopathological examination.

Results:) MR suggested metastatic lymph node involvement in 5 necks. In 2 of these, central necrosis was seen in the enlarged lymph nodes. In a third, a grouping of the lymph nodes was noted. Extracapsular spread was not present. Histopathological examination revealed metastatic lymph nodes in 7 of the 20 necks, the rate of clinically occult disease being 35%, and 4 of them had been accurately graded by MR. There was one false-positive MR examination. The MR sensitivity was 57.1% and specificity 92.3%.

Conclusion: MR may reveal metastatic lymph nodes in patients with no clinical evidence of metastasis. However, conventional MR techniques are not always sufficient for decision-making on surgery in cases of “N0 neck”).
Solid nonpalpable breast lesions
Authors: Ciatto S. , Del Turco M. Rosselli , Ambrogetti D. , Bravetti P. , Catarzi S. , Morrone D. , Cariaggi M. P.
Published: January 2010

Purpose: To evaluate the contribution of guided fine-needle aspiration cytology in reducing unnecessary biopsies of benign solid nonpalpable breast lesions with low suspicion of malignancy at mammography.

Material and Methods: An evaluation was made of a consecutive series of 2444 solid nonpalpable breast lesions detected by mammography and undergoing guided (sonography or stereotaxy) fine-needle aspiration cytology. Surgical biopsy was made in the presence of strong suspicion of malignancy at mammography and/or of abnormal cytology.

Results: The sensitivity was 96.7% and the specificity 77.7% (average follow-up 2.77 years). False-negative/inadequate cytology associated with low suspicion of malignancy at mammography resulted in a diagnostic delay in 27 cancer cases (invasive 20, intraductal 7). On the other hand, cytology led to surgical biopsy in 53 cancer cases which might not otherwise have been biopsied because of low radiological suspicion of cancer. Surgical biopsy of all cases, to avoid diagnostic delays, would have increased the benign biopsy rate by a factor of 4.5, with a rise in the benign: malignant biopsy ratio from 0.44:1 to 1.93:1.

Conclusion: Stereotaxy- or ultrasound-guided fine-needle aspiration cytology of nonpalpable mammographic abnormalities can achieve a sharp reduction in unnecessary benign biopsies in cases of low suspicion of malignancy at mammography.
Malignant lymphoma arising from chronic tuberculous empyema
Authors: Kinoshita T. , Ishii K. , Taira Y. , Naganuma H.
Published: January 2010

We report on a case of malignant lymphoma in the chest wall, associated with chronic tuberculous empyema. CT and MR imaging showed a soft-tissue mass contiguous with the empyema and invading the chest wall. MR imaging demonstrated a difference in signal intensity between the mass and the empyema. The extent of the chest-wall lymphoma was optimally delineated on fat-suppressed contrast-enhanced MR images.
Air enema used in the evaluation of acute colitis
Authors: Laveskog A. , Måre K. , Granqvist S. , Ståhlberg D.
Published: January 2010

Purpose: The purpose of this study was to evaluate air enema as a method of assessing acute colitis.

Material and Methods: Twenty-seven patients with symptoms of acute colitis underwent plain abdominal radiography, air enema, and colonoscopy within 48 h. The films were evaluated by 3 observers with different levels of experience, both independently and together, and the results were then compared to the findings at endoscopy.

Results: Air enema visualized a greater part of the colon than plain abdominal radiography. When air enema was compared to endoscopy as the reference, it showed good correlation, with a positive predictive value of 92% (sensitivity 62%, specificity 85%). Evaluation of the rectum was less accurate, a finding that emphasized the importance of rigid sigmoidoscopy.

Conclusion: Air enema is a useful diagnostic method in acute colitis, it is easily performed and tolerated well with no observed complications. It is also easy to interpret, as shown by a high level of agreement (k=0.67) among the 3 independent observers with very different levels of experience.
MR findings in cases of suspected impacted fracture of the femoral neck
Authors: Stiris M. G. , Lilleås F. G.
Published: January 2010

Purpose: To evaluate MR imaging of the hip in patients with a clinically suspected impacted fracture of the femoral neck in cases where conventional plain films show negative or equivocal findings.

Material and Methods: Twenty-seven such patients were prospectively examined by MR imaging with a 1.0 T unit, within 24 hours of admittance to hospital. A coronal T1-weighted turbo spin-echo sequence (n=27>), and a coronal STIR sequence (n=25) or a coronal T2-weighted turbo spin-echo fat saturation sequence (n=2) were used. The evaluations were made by 2 radiologists with experience in musculoskeletal radiology.

Results: There were 6 patients with a pertrochanteric fracture, 2 without and 4 with slight displacement. Five patients had an impacted fracture of the femoral neck, and 3 had a fracture of the superior pubic bone. Of 2 patients with advanced arthrosis, I had an impacted femoral neck fracture and the other a nondisplaced intertrochanteric fracture. There was 1 patient who had sustained a nondisplaced acetabular fracture with increased joint fluid and muscle contusions. Three patients had muscle contusions only. Two patients had bone marrow contusions only, while 2 others with advanced cox-arthrosis had increased joint fluid only. Three patients showed normal findings. Our findings led to emergency surgery in 13 cases, and conservative measures directed to the specific MR findings in 14 patients.

Conclusion: MR imaging should be the first modality of choice in examining patients with a clinically suspected impacted fracture of the femoral neck where conventional films show negative or equivocal findings.
Sonographic evaluation of hip effusion in children
Authors: Chan Y. L. , Cheng J. C. Y. , Metreweli C.
Published: January 2010

Purpose: To assess the difference in the sonographic appearance of hip effusions when the hip was placed in the extended and abducted position as compared to a neutral position.

Material and Methods: Twenty-one consecutive children (aged 2–14 years) with hip pain or limping were examined for hip effusions by means of ultrasound. The capsule-femoral-neck distance, the presence of joint fluid, and the shape of the anterior capsule were compared in hips in slight extension and abduction with those in hips in a neutral position.

Results: Of the 11 positive hip effusions, the maximal distance between the capsule and femoral neck was significantly larger (p < 0.005) in the extended and abducted hip position than in the neutral hip position, with a mean difference of 1.6 mm. Convex bulging of the anterior capsule was more confidently diagnosed in 3 hip effusions in the extended and abducted hip, and better visualization of fluid between the capsule and femoral neck was achieved in 4 joints in this posture.

Conclusion: The study demonstrated an improvement in the sonographic detection of hip effusion in the extended and abducted postition compared to the neutral position.
Grase: Ultra-fast turbo gradient spin-echo sequence
Authors: Trattnig S. , Breitenseher M. , Kontaxis G. , Helbich T. , Rand T. , Imhof H.
Published: January 2010

Purpose: Ultra-fast gradient and spin-echo (GRASE) imaging is a hybrid of turbo spin-echo (TSE) and echo-planar imaging (EPI). One scan consists of several spinechoes (SEs) (turbo factor, TF), each of which consists of a number of gradient echoes (EPI factor, EF). The aim of our study was to evaluate different combinations of TF and EF in GRASE imaging and to test its usefulness in musculoskeletal imaging.

Material and Methods: On a 1.0 T MR unit, 11 GRASE sequences with different combinations of TF and EF (TR/TE 2150/120 ms) were evaluated in phantom studies with respect to signal-to-noise (S/N) ratio, nonuniformity of images, and geometrical distortion. From this study, the optimal GRASE-sequence was applied to 25 patients with different joint pathologies and compared to a T2-weighted TSE sequence (TR/TE 2855/130 ms). Lesion visualization, conspicuity, overall image quality, and artifacts were qualitatively analyzed by two observers independently of each other.

Results: With respect to S/N ratio, signal nonuniformity, and geometrical distortion, the GRASE sequence with TF/EF 7/3 (S/N 47; signal nonuniformity 11.7%; distortion 1 pixel) proved to be superior to the other GRASE sequences within a scanning time of less than 120s. In a clinical study, the GRASE sequence proved superior to T2-weighted TSE (without fat suppression) in the visualization of bone-marrow and soft-tissue lesions ( p < 0.001) and ligamentous injuries, although the image quality was inferior.
Quantification of Area at Risk during Coronary Occlusion and Reperfusion by Means of MR Perfusion Imaging
Authors: Szolar Dieter H. , Saeed M. , Wendland M. , Sakuma H. , Stiskal M. A. , Derugin N. , Higgins C. B.
Published: January 2010

Purpose: Considerable clinical interest has focused on the size of ischemic myocardium. Fast MR imaging in conjunction with MR contrast media has the potential to identify hypoperfused and infarcted myocardium. This study used MR perfusion imaging to detect and quantify reperfused ischemic myocardium during a brief coronary occlusion and reperfusion, and to characterize the spatial extent of ischemic and reperfused ischemic myocardium relative to the “true” size of the area at risk as defined in histochemical morphometry at post mortem.

Material and Methods: The left circumflex (LCX) coronary artery in 8 dogs was occluded for 15 min followed by reperfusion in order to produce regional reversible myocardial ischemia. Perivascular Doppler probes were used to measure blood flow in the left anterior descending (LAD) and LCX coronary arteries. Fast inversion recovery-prepared gradient-recalled-echo images were acquired to delineate the ischemic area during occlusion, and the area of reversible ischemic injury at 1 and 30 min of reperfusion. The size of ischemic and reperfused ischemic myocardium were compared with the area at risk as determined by histochemical morphometry at post mortem.

Results: During LCX occlusion, LCX flow decreased from 16±1 to 0.2± 0.1 ml/min. On contrast-enhanced images, ischemic myocardium was evident as a zone of relatively low signal intensity (SI) compared to normal myocardium. The size of the ischemic region was significantly smaller (30± 2%) than at post mortem (36± 3%; p<0.05). Immediately after reperfusion, LCX flow increased to 83±11 ml/min and the contrast medium caused greater enhancement in the reperfused ischemic region than in the normal myocardium (69± 3 vs 42± 3 arbitrary units; p<0.05). The increase in regional SI correlated closely with the increase in regional blood flow (r=0.73). At 1 min of reperfusion, the size of the reperfused ischemic myocardium was larger (48± 3%, p<0.05) than the area at risk measured at post mortem. At 30 min of reperfusion, when the flow returned to baseline values (16± 2 ml/min), contrast bolus produced no differential enhancement between the 2 myocardial territories.

Conclusion: MR perfusion imaging has the potential to detect and quantify the size of ischemic myocardium and the region of post-occlusive hyperemia in the early reperfusion period. There is a significant direct linear relationship between the regional contrast enhancement of reperfused ischemic myocardium and the blood flow during post-occlusive hyperemia. The difference in the size of the area at risk at MR perfusion imaging and at histochemical morphometry may reflect an influence of coronary collateral circulation.
Diagnostic Accuracy of Mammography and Contrast-Enhanced MR Imaging in 238 Histologically Verified Breast Lesions
Authors: Boné B. , Péntek Z. , Perbeck L. , Veress B.
Published: January 2010

Purpose: To determine the sensitivity and specificity of X-ray mammography and of MR imaging in 238 consecutively operated breasts, and to correlate the findings to histopathological diagnosis.

Material and Methods: Over 15 months, 220 patients scheduled for breast surgery were examined consecutively, before surgery, by means of both mammography and MR imaging. of the 220 patients, 18 underwent bilateral breast surgery. The entire breast was examined by means of T1-weighted transversal images using a 3D fast low-angle shot (FLASH) sequence. One pre— and 2 post-contrast scans were performed. Each breast was examined by means of mammography and 3 views were applied as routine. All palpable and mammographically suspect lesions were examined on additional images as microfocus magnification or spot compression. The two methods were evaluated independently of each other.

Results: In total, 145 malignant and 93 benign lesions were found at histopathological examination. The sensitivity of mammography was 89% and MR imaging 92%. The specificity was 72% in both methods. When the results of the 2 methods were combined, a sensitivity of 99% and a specificity of 55% was achieved.

Conclusion: Mammography and MR imaging seemed to complement each other to produce a high sensitivity. Unfortunately it is impossible at present to supplement mammography with MR imaging in each patient as a routine owing to the current technical and financial limitations.
Computed Radiography for Characterisation of the Weight-Bearing Knee
Authors: Sanfridsson J. , Svahn G. , Jonsson K. , Ryd L.
Published: January 2010

Purpose: A new method for examining and measuring the weight-bearing knee in computed radiography (CR) and picture archiving and communication systems (PACS) has recently been developed on examination equipment used in QUESTOR Precision Radiography (QPR). QPR is a method for the standardised examination of the knee, and generates 9 angles (e.g. hip-knee-ankle (HKA) angle) and 10 distances, corrected for parallax and magnification. The aim of this present study was to evaluate the reproducibility of this newly developed method and to determine intra- and interobserver variation in its measurements.

Material and Methods: The images were generated on a CR system, archived, and transferred to a multimodality work-station that had a monitor with a resolution of 1280x1024 (1kx1k). Photostimulable phosphor plates were used to generate images with a matrix of 1760x2140 pixels (pixel size 0.2 mm, corresponding resolution 2.5 1p/mm). Ten volunteers without knee problems were examined twice, bilaterally, by 2 different radiology technologists.

Results: The total reproducibility of the method was good, offering an HKA reproducibility of ±2.64± in slight flexion and ± 1.62± in extension, at 95% confidence. The intra— and inter-observer variations were low with a reduction of the intra-observer variations in all measurements (except one) by a factor of 2.8 on average compared with the original QPR method for conventional film-screen radiography.

Conclusion: When QPR is modified for CR, it fulfils the requirement of reproducibility in measurements of the weight-bearing knee.