| 1. |
- Shalabi, A
(författare)
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Magnetic resonance imaging in chronic Achilles tendinopathy
- 2004
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Ingår i: Acta radiologica. Supplement. - : SAGE Publications. - 1600-5481 .- 0284-1851 .- 1600-0455. ; 45:432, s. 1-45
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Tidskriftsartikel (refereegranskat)abstract
- The main objective of this thesis was to evaluate and monitor the morphological response following treatment interventions in patients with chronic Achilles tendinopathy by using different MRI techniques. For this purpose, we investigated different types of sequences, including gadolinium contrast medium‐enhanced T1‐WI images (CME T1‐WI), and developed a precise method to measure tendon volume and mean intratendinous signal of the Achilles tendon. Study I aimed at evaluating 15 patients with chronic, painful Achilles tendinosis, before and 2 years after surgical treatment. There was marked regression of the intratendinous signal postoperatively. The most sensitive sequence for depicting an intratendinous lesion in this study was CME T1‐WI images. They showed a regression of the intratendinous signal abnormality from 13/15 patients preoperatively to 4/15 postoperatively. The clinical outcome was excellent in eight, good in five, fair in one and poor in one patient. In study II, the early contrast agent enhancement in the dynamically enhanced MRI signal (DEMRI) was correlated with the histopathologic findings in 15 patients with chronic Achilles tendinopathy. Early contrast enhancement (within the first 72 s) was seen in DEMRI in the symptomatic Achilles tendons, with a significant difference compared to the asymptomatic contralateral tendons. Increased severity of tendon changes, including fiber structure abnormality, increased vascularity, rounding of nuclei, and increased amount of glycosaminoglycans, correlated to CME. In study III, we developed a computerized 3‐D seed‐growing MRI technique to measure tendon volume and mean intratendinous signal. This technique showed an excellent inter‐ and intra‐observer reliability. The technique was also used to follow up prospectively the tendon adaptation and healing described in studies IV–VI. In study IV, using serial MRI during a period of 1 year, we evaluated the biological effect of tendon repair following iatrogenic tendon injury by five transversal ultrasound‐guided core biopsies employing a needle technique in chronic Achilles tendinopathy. Alterations found during healing, such as tendon volume and intratendinous reactive changes, could be monitored by MR imaging, and subsided as noted in the 7‐ and 12‐month follow‐ups. In study V, we evaluated the effect of treatment with a 3‐month, daily performed, heavy‐loaded calf‐muscle strength training program in 25 patients who had been suffering from chronic, painful Achilles tendinopathy. Tendon volume decreased by 14%, and the mean intratendinous signal by 23%. The clinical outcome was improved. In study VI, we revealed tendon adaptation immediately following calf‐muscle strength training. An MRI examination within 30 min of the performed exercises resulted in increased total tendon volume (12%) and mean intratendinous signal (31%). Conclusion: MRI techniques can be used as an adjunct to clinical evaluation by monitoring morphological effects following different treatment interventions, thereby adding evidence in clinical studies on patients with chronic Achilles tendinopathy.
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| 2. |
- Torres, Alvaro, et al.
(författare)
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Contrast-enhanced ultrasound using sulfur hexafluoride is safe in the pediatric setting
- 2017
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Ingår i: Acta Radiologica. - Stockholm : Karolinska Institutet, Dept of Clinical Science, Intervention and Technology. - 0284-1851 .- 1600-0455.
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Tidskriftsartikel (refereegranskat)abstract
- Background: Contrast-enhanced ultrasound (CEUS) by using sulfur hexafluoride microbubbles is not licensed for use in children, but its off-label use is widespread. Purpose: To outline our experience with the off-label use of CEUS in children, specifically with regards to safety. Material and Methods: We retrieved all records of 10681 patients aged under 18 years who underwent abdominal ultrasound (US) January 2004 to December 2014. We then identified those who underwent an abdominal CEUS using sulfur hexafluoride microbubbles. Electronic patient charts were used to verify the indication for contrast agent, dose, possible adverse effects as well as information on patient height, weight, and age. Results: We identified 173 patients (mean age, 11 years; range, 0.1–18 years) who underwent a total of 287 CEUS exams. Of all exams, 46% were performed on the native liver, 31% on a transplanted liver, and 23% on other organs. The indications were “circulatory status?” (40%), “characterization of lesion?” (40%), and miscellaneous (20%). Mean contrast dose was 2.3 mL (range, 0.1–8.1 mL). No immediate adverse effects were recorded. One patient experienced itching the day after, but this was considered to be a reaction to concomitantly administered fentanyl. Conclusion: The use of intravenous ultrasound contrast seems safe in patients aged under 18 years and our results do not support the current practice to restrict the use of CEUS in children.
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| 3. |
- Besjakov, Jack, et al.
(författare)
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Grading scale of radiographic findings in the pubic bone and symphysis in athletes.
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:1, s. 79-83
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: Radiographic abnormalities in the pubic bone and symphysis are often seen in athletes with groin pain. The aim was to create a grading scale of such radiologic changes. Material and Methods: Plain radiography of the pelvic ring including the pubic bone and the symphysis was performed in 20 male athletes, age 19-35, with long-standing uni- or bilateral groin pain. We used two control groups: Control group 1: 20 healthy age-matched men who had undergone radiologic examination of the pelvis due to trauma. Control group 2: 120 adults (66 men and 54 women) in 9 age groups between 15 and 90 years of age. These examinations were also evaluated for interobserver variance. Results and Conclusion: The grading scale was based on the type and the amount of the different changes, which were classified as follows: No bone changes (grade 0), slight bone changes (grade 1), intermediate changes (grade 2), and advanced changes (grade 3). The grading scale is easy to interpret and an otherwise troublesome communication between the radiologist and the physician was avoided. There was a high interobserver agreement with a high kappa value (0.8707). Male athletes with long-standing groin pain had abnormal bone changes in the symphysis significantly more frequently and more severely (p>0.001) than their age-matched references. In asymptomatic individuals such abnormalities increased in frequency with age both in men and women.
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| 4. |
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| 5. |
- Bülow, Margareta, et al.
(författare)
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Videoradiographic analysis of how carbonated thin liquids and thickened liquids affect the physiology of swallowing in subjects with aspiration on thin liquids.
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:4, s. 366-372
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To analyze how carbonated thin liquids affected the physiology of swallowing in dysphagic patients. Material and Methods: 40 patients were analyzed; 36 were neurologically impaired. During a therapeutic videoradiographic swallowing examination the patients had to swallow liquids with the following consistencies three times: thin, thickened and carbonated. The liquids were given in doses of 3 x 5 ml. The swallows were analyzed regarding penetration/aspiration, pharyngeal transit time and pharyngeal retention. Results: Significant difference was found regarding penetration/aspiration when comparisons were made between thin liquid and carbonated thin liquid (p<0.0001). Carbonated liquid reduced the penetration to the airways. The comparison between thin liquid and thickened liquid (p<0.0001) showed significant less penetration with thickened liquids. Pharyngeal transit time was reduced both when comparing thin liquid with thin carbonated liquid (p<0.0001) and thickened liquid (p<0.0001). Pharyngeal retention was significantly reduced (p<0.0001) with carbonated thin liquid compared to thickened liquid. The comparison of thin liquids and carbonated thin liquids showed p = 0.0013, thin and thickened liquids p = 0.0097. Conclusions: Carbonated liquids reduced penetration/aspiration into the airways, reduced pharyngeal retention and pharyngeal transit time became shorter. Therefore, carbonated liquids are a valuable treatment option for patients with penetration/aspiration. Thickened liquids may still be an option for patients who cannot tolerate carbonated liquids and liquids with this consistency are safer than thin liquids.
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| 6. |
- Cronberg, Carin, et al.
(författare)
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Peripheral arterial disease.
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:1, s. 59-66
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Tidskriftsartikel (refereegranskat)
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| 7. |
- Ekberg, Olle
(författare)
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The symptomatic esophagus and GERD
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:2, s. 119-120
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Tidskriftsartikel (refereegranskat)
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| 8. |
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| 9. |
- Hakansson, K, et al.
(författare)
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MR and ultrasound in screening of patients with suspected biliary tract disease
- 2002
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 43:1, s. 80-86
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Tidskriftsartikel (refereegranskat)abstract
- Purpose The diagnostic value and cost-efficiency of MR imaging were compared with US before endoscopic retrograde cholangiopancreatography (ERCP) in patients with clinically suspected biliary tract disease. Material and Methods: In a prospective study of 219 patients, 85 were examined with both MR and US before ERCP. Results: To find the correct diagnosis in the jaundiced patients the sensitivity of US, MR and FRCP was 53%, 93%, and 89%, respectively. In the patients with abdominal upper quadrant pain and normal serum bilirubin, the sensitivity of US, MR and ERCP was 50%, 100% and 70%, respectively. Examination with MR costs four times more than US. Screening with US and supplemental MR in non-diagnostic cases would cost 80% of the total amount compared to screening with MR only. Conclusion: MR had a higher sensitivity than US for diagnosing biliary tract disease and MR was superior to US in visualising stones in the common bile duct and in diagnosing the cause of cholestasis. However, screening with US and supplemental MR in non-diagnostic cases is at present most cost-effective. With increased accessibility and slightly lower costs, MR will probably replace US as screening method in patients with suspected biliary tract disease.
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| 10. |
- Hakansson, K, et al.
(författare)
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MR characteristics of acute cholangitis
- 2002
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 43:2, s. 175-179
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To describe the MR appearance of acute cholangitis and discuss the role of MR imaging as a diagnostic method in this disease. Material and Methods: Of 60 patients with clinical acute cholangitis, 12 were examined with MR before endoscopic retrograde pancreatography (ERCP). A retrospective review was performed of MR and ERCP findings. The MR findings registered were presence of biliary duct dilatation, intraluminal filling defects due to stones or sludge, bands of mucosal oedema of the biliary ducts, intra- and retroperitoneal oedema/fluid, and definition of the cause of obstruction, e.g. stones, stenosis or tumour was made. Results: Acute cholangitis was related to obstruction from choledocholithiasis (n = 8), pancreatic cancer (n = 1), benign biliary duct stricture (n = 1), papillary stenosis (n = 1) and without evidence of an obstructing cause (n = 1). One patient had an acute obstructive suppurative (toxic) cholangitis. Conclusion: MR imaging has a role in the non-invasive radiographic arsenal of techniques to confirm or exclude the diagnosis of acute cholangitis, especially in older patients where the clinical symptoms may be vague.
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| 11. |
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| 12. |
- Hormann, M, et al.
(författare)
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Videofluoroscopy of deglutition in children after repair of esophageal atresia
- 2002
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 43:5, s. 507-510
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To evaluate the functional disorders of the oral and pharyngeal phases of deglutition after repair of esophageal atresia in children. Material and Methods: 19 children (10 girls, 9 boys, mean age 22 months) underwent videofluoroscopy of deglutition after repair of esophageal atresia. The videofluoroscopic studies were assessed according to functional and morphological changes in the oral, pharyngeal and esophageal phases. The persistence of radiologic findings on videofluoroscopy was determined. Results: The oral phase was normal in all patients. The main functional disorder of the pharyngeal phase was aspiration in 7 (37%) children. A completely normal deglutition in the pharyngeal and esophageal phases was not seen in any patient. Conclusion: Videofluoroscopy after repair of esophageal atresia is helpful in differentiation of functional and morphological disorders that can lead to prandial aspiration and have an influence on the decision about continued therapy.
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| 13. |
- Kesek, Pavel, et al.
(författare)
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Herniographic findings in athletes with unclear groin pain.
- 2002
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 43:6, s. 603-608
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Tidskriftsartikel (refereegranskat)abstract
- Background:Groin pain in athletes is a common symptom and may, among many other entities, be caused by skeletal changes in the symphysis and the pubic bone or hernia. Material and Methods:Herniographies in 51 athletes - mainly soccer players - with unclear groin pain were reviewed. The prevalence of various hernias and skeletal changes at the symphysis and os pubis was registered. A questionnaire was also sent to the patients 3-20 years after the herniography. Results:A hernia was found in 13 patients. Four patients had an indirect inguinal hernia. Eight patients had a direct inguinal hernia and 1 had an obturator hernia. The prevalence of direct inguinal hernia was higher than expected in young men. This may be explained by strain at physical exercise. Bone changes at the pubic symphysis were found in 32 patients, 21 of whom had advanced changes. Conclusion:A hernia can be found with herniography in one-fourth of athletes with long-standing unclear groin pain. Therefore herniography should be included in the diagnostic procedure. Lesions of the symphysis may be the result of strain of tendons, ligaments and fascias. This may predispose for an inguinal hernia as well.
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| 14. |
- Lindén, B, et al.
(författare)
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Osteochondritis dissecans of the hip.
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:1, s. 67-71
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Tidskriftsartikel (refereegranskat)
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| 15. |
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| 16. |
- Månsson, S, et al.
(författare)
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Echo-planar MR imaging of dissolved hyperpolarized 129Xe : Potential for MR angiography
- 2002
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Ingår i: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 43:5, s. 60-455
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The feasibility of hyperpolarized 129Xe for fast MR angiography (MRA) was evaluated using the echo-planar imaging (EPI) technique.MATERIAL AND METHODS: Hyperpolarized Xe gas was dissolved in ethanol, a carrier agent with high solubility for Xe (Ostwald solubility coefficient 2.5) and long relaxation times. The dissolved Xe was injected as a bolus into a flow phantom where the mean flow velocity was 15 cm/s. Ultrafast EPI images with 44 ms scan time were acquired of the flowing bolus and the signal-to-noise ratios (SNR) were measured.RESULTS: The relaxation times of hyperpolarized Xe in ethanol were measured to T1=160+/-11 s and T2 approximately 20 s. The resulting images of the flowing liquid were of reasonable quality and had an SNR of about 70.CONCLUSION: Based on the SNR of the obtained Xe EPI images, it was estimated that rapid in vivo MRA with 129Xe may be feasible, provided that an efficient, biologically acceptable carrier for Xe can be found and polarization levels of more than 25% can be achieved in isotopically enriched 129Xe.
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| 17. |
- Svensson, Jonas
(författare)
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Contrast-enhanced magnetic resonance angiography.
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 1600-0455 .- 0284-1851. ; 44:S429, s. 7-7
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Forskningsöversikt (refereegranskat)abstract
- Contrast-enhanced magnetic resonance angiography (CE-MRA) is a diagnostic method for imaging of vascular structures based on nuclear magnetic resonance. Vascular enhancement is achieved by injection of a contrast medium (CM). Studies were performed using two different types of CM: conventional paramagnetic CM, and a new type of CM based on hyperpolarized (HP) nuclei. The effects of varying CM concentration with time during image acquisition were studied by means of computer simulations using two different models. It was shown that a rapid concentration variation during encoding of the central parts of k-space could result in signal loss and severe image artifacts. The results were confirmed qualitatively with phantom experiments. A postprocessing method was developed to address problems with simultaneous enhancement of arteries and veins in CE-MRA of the lower extremities. The method was based on the difference in flow-induced phase in the two vessel types. Evaluation of the method was performed with flow phantom measurements and with CE-MRA in two volunteers using standard pulse sequences. The flow-induced phase in the vessels of interest was sufficient to distinguish arteries from veins in the superior-inferior direction. Using this method, the venous enhancement could be extinguished. The possibility of using HP nuclei as CM for CE-MRA was evaluated. Signal expressions for a flow of HP CM imaged with a gradient echo sequence were derived. These signal expressions were confirmed in phantom experiments using HP 129Xe dissolved in ethanol. Studies were also performed with a new CM based on HP 13C. The CM had very long relaxation times (T1,in vivo/T2,in vivo≈ 38/1.3 s). The long relaxation times were utilized in imaging with a fully balanced steady-state free precession pulse sequence (trueFISP), where the optimal flip angle was found to be 180°. CE-MRA with the 13C-based CM in rats resulted in images with high vascular SNR (~500). CE-MRA is a useful clinical tool for diagnosing vascular disease. With the development of new contrast media, based on hyperpolarized nuclei for example, there is a potential for further improvement in the signal levels that can be achieved, enabling a standard of imaging of vessels that is not possible today.
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| 18. |
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| 19. |
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| 20. |
- Engellau, Lena, et al.
(författare)
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Measurements before endovascular repair of abdominal aortic aneurysms : MR imaging with MRA vs. angiography and CT
- 2003
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Ingår i: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 44:2, s. 177-184
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: 1) To compare measurements obtained with MR imaging (MRI)/contrast-enhanced MR angiography (CE MRA) with measurements obtained with angiography (DSA) and CT, for stent-graft sizing of abdominal aortic aneurysms (AAA). 2) To compare MRA measurements obtained with the two post processing techniques MIP (maximum intensity projection) and VRT (3D volume rendering technique).Material and Methods: The prospective study included 20 consecutive patients with AAA identified by DSA and CT as suitable for endovascular repair. For the study, MRI/CE MRA was performed. Five measurement variables for stent-graft sizing were chosen. Comparisons were made between MRI/CE MRA, DSA and CT, and between observers. Comparisons were also made between MIP and VRT.Results: Significantly shorter lengths were obtained with MRA-MIP than with DSA. Three out of six diameter measurements were significantly smaller on MRI/CE MRA than on DSA and CT. No significant differences were found between the observers. One diameter measurement was significantly smaller on MIP than on VRT, while the other measurements showed no significant differences.Conclusion: The length measurements obtained with MRA-MIP were probably more correct than those with DSA. For more reliable diameter measurements with CE MRA, improvements of the technique, including VRT reconstructions and a standardized determination of the vessel boundaries, are needed.
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| 21. |
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| 22. |
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| 23. |
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| 24. |
- Leifland, K, et al.
(författare)
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Comparison of stereotactic fine needle aspiration cytology and core needle biopsy in 522 non-palpable breast lesions
- 2003
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Ingår i: Acta radiologica (Stockholm, Sweden : 1987). - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 44:4, s. 387-391
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: To compare the accuracy of stereotactic fine needle aspiration cytologies (S-FNAC) and stereotactic core needle biopsies (S-CNB) in non-palpable breast lesions. Material and Methods: Between May 1993 and December 2000, 696 patients with mammographically detected lesions were biopsied both with S-FNAC and S-CNB. S-FNAC was performed with spinal needle 22- or 20-gauge and S-CNB with an automated 14-gauge gun. Results: Of the 696 patients, 522 (75%) underwent breast surgery with postoperative histopathology. In all, 448 of these 522 women (86%) had malignant and 74 (14%) had benign lesions. S-FNAC revealed cancer in 254 (57%) and probable cancer in 48 (11%) (sensitivity 68%, specificity 99.6%) and S-CNB revealed cancer in 388 (87%) and probable cancer in 18 (4%) (sensitivity 90%, specificity 98.8%) of these 448 patients. Conclusion: S-CNB was more accurate than S-FNAC in the diagnosis of non-palpable breast cancer.
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| 25. |
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