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  • 1.
    Alobeidi, Hanan
    et al.
    Department of Radiology, Örebro university Hospital, Region Örebro län, Örebro, Sweden.
    Alshamari, Muhammed
    Örebro University, School of Medical Sciences. Department of Radiology.
    Widell, Jonas
    Department of Radiology, Örebro university Hospital, Region Örebro län, Örebro, Sweden.
    Eriksson, Tomas
    Department of Radiology, Örebro university Hospital, Region Örebro län, Örebro, Sweden.
    Lidén, Mats
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology.
    Minimizing contrast media dose in CT pulmonary angiography with high-pitch technique2020In: British Journal of Radiology, ISSN 0007-1285, E-ISSN 1748-880X, Vol. 93, no 1111, article id 20190995Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To perform CT pulmonary angiography (CTPA) using a minimal amount of iodinated contrast media.

    METHODS: 47 patients (25 females) with mean age 69 years (range 41-82 years) referred for contrast-enhanced chest CT were prospectively included in this Phase IV clinical drug trial. All participants underwent a study specific CTPA in addition to the chest CT. The participants received 80 mg I/kg body weight Iohexol contrast media using a preparatory saline bolus, a dual flow contrast/saline bolus and a saline flush, and a scanner protocol with 80 kVp dual source high-pitch mode. Three readers independently assessed the image quality on the 3-point scale non-diagnostic, adequate or good-excellent image quality. Additionally, the pulmonary arterial contrast opacification was measured.

    RESULTS: On average, the patients received 16.8 ml Iohexol 350 mg I/mL (range 12-20 ml). Mean patient weight was 71 kg (range 50-85 kg). Identically for all readers, pulmonary embolism (PE) was detected in 1/47 participants. The median number of examinations visually scored concerning pulmonary embolism as good-excellent was 47/47 (range 44-47); adequate 0/47 (0-3) and non-diagnostic 0/47 (range 0-0). The proportion adequate or better examinations was for all readers 47/47, 100% [95% confidence interval 92-100%]. The mean attenuation ± standard deviation in the pulmonary trunk was 325 ± 72 Hounsfield unit (range 165-531 Hounsfield unit).

    CONCLUSIONS: Diagnostic CTPA with 17 ml contrast media is possible in non-obese patients using low kVp, high pitch and carefully designed contrast media administration.

    ADVANCES IN KNOWLEDGE: By combining several procedures in a CTPA protocol, the contrast media dose can be minimized.

  • 2.
    Alshamari, Muhammed
    Örebro University, School of Medical Sciences.
    Low-dose computed tomography of the abdomen and lumbar spine2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Radiography is a common radiologic investigation despite abundant evidence of its limited diagnostic value. On the other hand, computed tomography (CT) has a high diagnostic value and is widely considered to be among the most important advances in medicine. However, CT exposes patients to a higher radiation dose and it might therefore not be acceptable simply to replace radiography with CT, despite the powerful diagnostic value of this technique. At the expense of reduced CT image quality, which could be adjusted to the diagnostic needs, low-dose CT of abdomen and lumbar spine can be performed at similar dose to radiography. The aim of the current thesis project was to evaluate low-dose CT of the abdomen and lumbar spine and to compare it with radiography. The hypothesis was that CT would give better image quality and diagnostic information compared to radiography at similar dose levels. Firstly, the diagnostic accuracy of low-dose CT of the abdomen was evaluated. Results showed that low-dose CT of abdomen has a high sensitivity and specificity compared to radiography, i.e., it has higher diagnostic accuracy. Similar results were obtained from our systematic review. Secondly, in a phantom study, an ovine phantom was scanned at various CT settings. The image quality was evaluated to obtain a protocol for the optimal settings for low-dose CT of lumbar spine at 1 mSv. This new protocol was then used in a clinical study to assess the image quality of low-dose CT of the lumbar spine and compare it to radiography. Results showed that low-dose CT has significantly better image quality than radiography. Finally, the impact of Iterative reconstruction (IR) on image quality of lumbar spine CT was tested. Iterative reconstruction is a recent CT technique aimed to reduce radiation dose and/or improve image quality. The results showed that the use of medium strength IR levels in the reconstruction of CT image improves image quality compared to filtered back projection. In conclusion, low-dose CT of the abdomen and lumbar spine, at about 1 mSv, has better image quality and gives diagnostic information compared to radiography at similar dose levels and it could therefore replace radiography.

    List of papers
    1. Diagnostic accuracy of low-dose CT compared with abdominal radiography in non-traumatic acute abdominal pain: prospective study and systematic review
    Open this publication in new window or tab >>Diagnostic accuracy of low-dose CT compared with abdominal radiography in non-traumatic acute abdominal pain: prospective study and systematic review
    Show others...
    2016 (English)In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 26, no 6, p. 1766-1774Article, review/survey (Refereed) Published
    Abstract [en]

    Objectives: Abdominal radiography is frequently used in acute abdominal non-traumatic pain despite the availability of more advanced diagnostic modalities. This study evaluates the diagnostic accuracy of low-dose CT compared with abdominal radiography, at similar radiation dose levels.

    Methods: Fifty-eight patients were imaged with both methods and were reviewed independently by three radiologists. The reference standard was obtained from the diagnosis in medical records. Sensitivity and specificity were calculated. A systematic review was performed after a literature search, finding a total of six relevant studies including the present.

    Results: Overall sensitivity with 95 % CI for CT was 75 % (66-83 %) and 46 % (37-56 %) for radiography. Specificity was 87 % (77-94 %) for both methods. In the systematic review the overall sensitivity for CT varied between 75 and 96 % with specificity from 83 to 95 % while the overall sensitivity for abdominal radiography varied between 30 and 77 % with specificity 75 to 88 %.

    Conclusions: Based on the current study and available evidence, low-dose CT has higher diagnostic accuracy than abdominal radiography and it should, where logistically possible, replace abdominal radiography in the workup of adult patients with acute non-traumatic abdominal pain.

    Key points: • Low-dose CT has a higher diagnostic accuracy than radiography. • A systematic review shows that CT has better diagnostic accuracy than radiography. • Radiography has no place in the workup of acute non-traumatic abdominal pain.

    Place, publisher, year, edition, pages
    New York: Springer, 2016
    Keywords
    X-ray computed tomography, abdominal radiography, sensitivity and specificity, abdominal pain, abdomen, acute
    National Category
    Radiology, Nuclear Medicine and Medical Imaging
    Research subject
    Radiology
    Identifiers
    urn:nbn:se:oru:diva-47089 (URN)10.1007/s00330-015-3984-9 (DOI)000376100100030 ()26385800 (PubMedID)2-s2.0-84942013953 (Scopus ID)
    Note

    Funding Agency:

    Region Örebro County

    Available from: 2015-12-16 Created: 2015-12-16 Last updated: 2023-05-22Bibliographically approved
    2. Low-dose computed tomography of the lumbar spine: a phantom study on imaging parameters and image quality
    Open this publication in new window or tab >>Low-dose computed tomography of the lumbar spine: a phantom study on imaging parameters and image quality
    2014 (English)In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 55, no 7, p. 824-832Article in journal (Refereed) Published
    Abstract [en]

    Background: Lumbar spine radiography has limited diagnostic value but low radiation dose compared with computed tomography (CT). The average effective radiation dose from lumbar spine radiography is about 1.1 mSv. Low-dose lumbar spine CT may be an alternative to increase the diagnostic value at low radiation dose, around 1 mSv.

    Purpose: To determine the optimal settings for low-dose lumbar spine CT simultaneously aiming for the highest diagnostic image quality possible.

    Material and Methods: An ovine lower thoracic and lumbar spine phantom, with all soft tissues around the vertebrae preserved except the skin, was placed in a 20 L plastic container filled with water. The phantom was scanned repeatedly with various technical settings; different tube potential, reference mAs, and with different convolution filters. Five radiologists evaluated the image quality according to a modification of the European guidelines for multislice computed tomography (MSCT) quality criteria for lumbar spine CT 2004. In a visual comparison the different scans were also ranked subjectively according to perceived image quality. Image noise and contrast were measured.

    Results: A tube potential of 120 kV with reference mAs 30 and medium or medium smooth convolution filter gave the best image quality at a sub-millisievert dose level, i.e. with an effective dose comparable to that from lumbar spine radiography.

    Conclusion: Low-dose lumbar spine CT thus opens a possibility to substitute lumbar spine radiography with CT without obvious increase in radiation dose.

    Keywords
    conventional radiography; CT; spine; structures; techniques
    National Category
    Radiology, Nuclear Medicine and Medical Imaging
    Research subject
    Radiology
    Identifiers
    urn:nbn:se:oru:diva-38243 (URN)10.1177/0284185113509615 (DOI)000342575300008 ()2-s2.0-84907878366 (Scopus ID)
    Available from: 2014-11-03 Created: 2014-10-30 Last updated: 2020-12-01Bibliographically approved
    3. Low dose CT of the lumbar spine compared with radiography: a study on image quality with implications for clinical practice
    Open this publication in new window or tab >>Low dose CT of the lumbar spine compared with radiography: a study on image quality with implications for clinical practice
    Show others...
    2016 (English)In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 57, no 5, p. 602-611Article in journal (Refereed) Published
    Abstract [en]

    Background: Lumbar spine radiography is often performed instead of CT for radiation dose concerns.

    Purpose: To compare image quality and diagnostic information from low dose lumbar spine CT at an effective dose of about 1 mSv with lumbar spine radiography.

    Material and Methods: Fifty-one patients were examined by both methods. Five reviewers scored all examinations on eight image quality criteria using a five-graded scale and also assessed three common pathologic changes.

    Results: Low dose CT scored better than radiography on the following: sharp reproduction of disc profile and vertebral end-plates (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3-2.5), intervertebral foramina and pedicles (OR, 4.3; 95% CI, 3.1-5.9), intervertebral joints (OR, 139; 95% CI, 59-326), spinous and transverse processes (OR, 7.0; 95% CI, 4.3-11.2), sacro-iliac joints (OR, 4.2; 95% CI, 3.2-5.7), reproduction of the adjacent soft tissues (OR, 2.9; 95% CI, 2.1-4.0), and absence of any obscuring superimposed gastrointestinal gas and contents (OR, 188; 95% CI, 66-539). Radiography scored better on sharp reproduction of cortical and trabecular bone (OR, 0.3; 95% CI, 0.2-0.4). The reviewers visualized disk degeneration, spondylosis/diffuse idiopathic skeletal hyperostosis (DISH) and intervertebral joint osteoarthritis more clearly and were more certain with low dose CT. Mean time to review low dose CT was 204 s (95% CI, 194-214 s.), radiography 152 s (95% CI, 146-158 s.). The effective dose for low dose CT was 1.0-1.1 mSv, for radiography 0.7 mSv.

    Conclusion: Low dose lumbar spine CT at about 1 mSv has superior image quality to lumbar spine radiography with more anatomical and diagnostic information.

    Place, publisher, year, edition, pages
    London, United Kingdom: Sage Publications, 2016
    Keywords
    Radiation dose, radiography, tomography, X-ray computed, axial skeleton
    National Category
    Radiology, Nuclear Medicine and Medical Imaging
    Research subject
    Radiology
    Identifiers
    urn:nbn:se:oru:diva-47090 (URN)10.1177/0284185115595667 (DOI)000374327600014 ()26221055 (PubMedID)2-s2.0-84978646277 (Scopus ID)
    Available from: 2015-12-16 Created: 2015-12-16 Last updated: 2024-03-06Bibliographically approved
    4. Impact of iterative reconstruction on image quality of low-dose CT of the lumbar spine
    Open this publication in new window or tab >>Impact of iterative reconstruction on image quality of low-dose CT of the lumbar spine
    Show others...
    (English)Manuscript (preprint) (Other academic)
    National Category
    Surgery
    Research subject
    Surgery
    Identifiers
    urn:nbn:se:oru:diva-49423 (URN)
    Available from: 2016-03-17 Created: 2016-03-17 Last updated: 2024-03-06Bibliographically approved
    Download full text (pdf)
    Introductory chapter
    Download (pdf)
    Spikblad
    Download (pdf)
    Cover
  • 3.
    Alshamari, Muhammed
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Geijer, Mats
    Center for Medical Imaging and Physiology, Skåne University Hospital, Lund, Sweden; Lund University, Lund, Sweden.
    Norrman, Eva
    Örebro University Hospital.
    Geijer, Håkan
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Low-dose computed tomography of the lumbar spine: a phantom study on imaging parameters and image quality2014In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 55, no 7, p. 824-832Article in journal (Refereed)
    Abstract [en]

    Background: Lumbar spine radiography has limited diagnostic value but low radiation dose compared with computed tomography (CT). The average effective radiation dose from lumbar spine radiography is about 1.1 mSv. Low-dose lumbar spine CT may be an alternative to increase the diagnostic value at low radiation dose, around 1 mSv.

    Purpose: To determine the optimal settings for low-dose lumbar spine CT simultaneously aiming for the highest diagnostic image quality possible.

    Material and Methods: An ovine lower thoracic and lumbar spine phantom, with all soft tissues around the vertebrae preserved except the skin, was placed in a 20 L plastic container filled with water. The phantom was scanned repeatedly with various technical settings; different tube potential, reference mAs, and with different convolution filters. Five radiologists evaluated the image quality according to a modification of the European guidelines for multislice computed tomography (MSCT) quality criteria for lumbar spine CT 2004. In a visual comparison the different scans were also ranked subjectively according to perceived image quality. Image noise and contrast were measured.

    Results: A tube potential of 120 kV with reference mAs 30 and medium or medium smooth convolution filter gave the best image quality at a sub-millisievert dose level, i.e. with an effective dose comparable to that from lumbar spine radiography.

    Conclusion: Low-dose lumbar spine CT thus opens a possibility to substitute lumbar spine radiography with CT without obvious increase in radiation dose.

  • 4.
    Alshamari, Muhammed
    et al.
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Geijer, Mats
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden; Department of Medical Imaging and Physiology, Skåne University Hospital, Lund University, Lund, Sweden.
    Norrman, Eva
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Medical Physics, Örebro University Hospital, Örebro, Sweden.
    Lidén, Mats
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Krauss, Wolfgang
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Jendeberg, Johan
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Magnuson, Anders
    Örebro University Hospital.
    Geijer, Håkan
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Impact of iterative reconstruction on image quality of low-dose CT of the lumbar spine2017In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 58, no 6, p. 702-709Article in journal (Refereed)
    Abstract [en]

    Background: Iterative reconstruction (IR) is a recent reconstruction algorithm for computed tomography (CT) that can be used instead of the standard algorithm, filtered back projection (FBP), to reduce radiation dose and/or improve image quality.

    Purpose: To evaluate and compare the image quality of low-dose CT of the lumbar spine reconstructed with IR to conventional FBP, without further reduction of radiation dose.

    Material and Methods: Low-dose CT on 55 patients was performed on a Siemens scanner using 120 kV tube voltage, 30 reference mAs, and automatic dose modulation. From raw CT data, lumbar spine CT images were reconstructed with a medium filter (B41f) using FBP and four levels of IR (levels 2-5). Five reviewers scored all images on seven image quality criteria according to the European guidelines on quality criteria for CT, using a five-grade scale. A side-by-side comparison was also performed.

    Results: There was significant improvement in image quality for IR (levels 2-4) compared to FBP. According to visual grading regression, odds ratios of all criteria with 95% confidence intervals for IR2, IR3, IR4, and IR5 were: 1.59 (1.39-1.83), 1.74 (1.51-1.99), 1.68 (1.46-1.93), and 1.08 (0.94-1.23), respectively. In the side-by-side comparison of all reconstructions, images with IR (levels 2-4) received the highest scores. The mean overall CTDIvol was 1.70 mGy (SD 0.46; range, 1.01-3.83 mGy). Image noise decreased in a linear fashion with increased strength of IR.

    Conclusion: Iterative reconstruction at levels 2, 3, and 4 improves image quality of low-dose CT of the lumbar spine compared to FPB.

  • 5.
    Alshamari, Muhammed
    et al.
    Örebro University, School of Medical Sciences. Department of Radiology.
    Geijer, Mats
    Department of Radiology, School of Medical Sciences, Örebro University, Örebro, Sweden; Department of Medical Imaging and Physiology, Skåne University Hospital, Lund; Lund University, Lund, Sweden.
    Norrman, Eva
    Department of Medical Physics, School of Medical Sciences, Örebro University, Örebro, Sweden.
    Lidén, Mats
    Örebro University, School of Health Sciences.
    Krauss, Wolfgang
    Örebro University, School of Health Sciences.
    Jendeberg, Johan
    Örebro University, School of Health Sciences.
    Magnuson, Anders
    Clinical Epidemiology and Biostatistics, School of Medical Sciences, Örebro University, Örebro, Sweden.
    Geijer, Håkan
    Örebro University, School of Health Sciences.
    Impact of iterative reconstruction on image quality of low-dose CT of the lumbar spineManuscript (preprint) (Other academic)
  • 6.
    Alshamari, Muhammed
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Radiology, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Geijer, Mats
    Department of Medical Imaging and Physiology, Skåne University Hospital, Lund University, Lund, Sweden.
    Norrman, Eva
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Medical Physics,, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Lidén, Mats
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Radiology, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Krauss, Wolfgang
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Radiology, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Wilamowski, Franciszek
    Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Geijer, Håkan
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Radiology, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Low dose CT of the lumbar spine compared with radiography: a study on image quality with implications for clinical practice2016In: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 57, no 5, p. 602-611Article in journal (Refereed)
    Abstract [en]

    Background: Lumbar spine radiography is often performed instead of CT for radiation dose concerns.

    Purpose: To compare image quality and diagnostic information from low dose lumbar spine CT at an effective dose of about 1 mSv with lumbar spine radiography.

    Material and Methods: Fifty-one patients were examined by both methods. Five reviewers scored all examinations on eight image quality criteria using a five-graded scale and also assessed three common pathologic changes.

    Results: Low dose CT scored better than radiography on the following: sharp reproduction of disc profile and vertebral end-plates (odds ratio [OR], 1.8; 95% confidence interval [CI], 1.3-2.5), intervertebral foramina and pedicles (OR, 4.3; 95% CI, 3.1-5.9), intervertebral joints (OR, 139; 95% CI, 59-326), spinous and transverse processes (OR, 7.0; 95% CI, 4.3-11.2), sacro-iliac joints (OR, 4.2; 95% CI, 3.2-5.7), reproduction of the adjacent soft tissues (OR, 2.9; 95% CI, 2.1-4.0), and absence of any obscuring superimposed gastrointestinal gas and contents (OR, 188; 95% CI, 66-539). Radiography scored better on sharp reproduction of cortical and trabecular bone (OR, 0.3; 95% CI, 0.2-0.4). The reviewers visualized disk degeneration, spondylosis/diffuse idiopathic skeletal hyperostosis (DISH) and intervertebral joint osteoarthritis more clearly and were more certain with low dose CT. Mean time to review low dose CT was 204 s (95% CI, 194-214 s.), radiography 152 s (95% CI, 146-158 s.). The effective dose for low dose CT was 1.0-1.1 mSv, for radiography 0.7 mSv.

    Conclusion: Low dose lumbar spine CT at about 1 mSv has superior image quality to lumbar spine radiography with more anatomical and diagnostic information.

  • 7.
    Alshamari, Muhammed
    et al.
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Norrman, Eva
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Medical Physics, Örebro University Hospital, Örebro, Sweden.
    Geijer, Mats
    Department of Medical Imaging and Physiology, Lund University, Lund, Sweden; Skåne University Hospital, Lund, Sweden.
    Jansson, Kjell
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Surgery, Örebro University Hospital, Örebro, Sweden.
    Geijer, Håkan
    Örebro University, School of Health and Medical Sciences, Örebro University, Sweden. Department of Radiology, Örebro University Hospital, Örebro, Sweden.
    Diagnostic accuracy of low-dose CT compared with abdominal radiography in non-traumatic acute abdominal pain: prospective study and systematic review2016In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 26, no 6, p. 1766-1774Article, review/survey (Refereed)
    Abstract [en]

    Objectives: Abdominal radiography is frequently used in acute abdominal non-traumatic pain despite the availability of more advanced diagnostic modalities. This study evaluates the diagnostic accuracy of low-dose CT compared with abdominal radiography, at similar radiation dose levels.

    Methods: Fifty-eight patients were imaged with both methods and were reviewed independently by three radiologists. The reference standard was obtained from the diagnosis in medical records. Sensitivity and specificity were calculated. A systematic review was performed after a literature search, finding a total of six relevant studies including the present.

    Results: Overall sensitivity with 95 % CI for CT was 75 % (66-83 %) and 46 % (37-56 %) for radiography. Specificity was 87 % (77-94 %) for both methods. In the systematic review the overall sensitivity for CT varied between 75 and 96 % with specificity from 83 to 95 % while the overall sensitivity for abdominal radiography varied between 30 and 77 % with specificity 75 to 88 %.

    Conclusions: Based on the current study and available evidence, low-dose CT has higher diagnostic accuracy than abdominal radiography and it should, where logistically possible, replace abdominal radiography in the workup of adult patients with acute non-traumatic abdominal pain.

    Key points: • Low-dose CT has a higher diagnostic accuracy than radiography. • A systematic review shows that CT has better diagnostic accuracy than radiography. • Radiography has no place in the workup of acute non-traumatic abdominal pain.

  • 8. Al-Ubeidy, H.
    et al.
    Alshamari, Muhammed
    Örebro University, School of Medical Sciences. Örebro University Hospital.
    Widell, J.
    Eriksson, T.
    Lidén, Mats
    Örebro University, School of Medical Sciences.
    High-pitch, low-kVp computed tomography for ruling out pulmonary embolism with 17-mL contrast media2019Conference paper (Refereed)
  • 9.
    Baban, Bayar
    et al.
    Örebro University, School of Medical Sciences. Department of Surgery, School of Medical Sciences, Faculty of Medicne and Health, Örebro University, Örebro, Sweden.
    Eklund, Daniel
    Örebro University, School of Medical Sciences.
    Tuerxun, Kedeye
    Örebro University, School of Medical Sciences.
    Alshamari, Muhammed
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology.
    Laviano, Alessandro
    Department of Translational and Precision Medicine, Sapienza University, Rome, Italy.
    Ljungqvist, Olle
    Örebro University, School of Medical Sciences. Department of Surgery, School of Medical Sciences, Faculty of Medicne and Health, Örebro University, Örebro, Sweden.
    Särndahl, Eva
    Örebro University, School of Medical Sciences.
    Altered insulin sensitivity and immune function in patients with colorectal cancer2023In: Clinical Nutrition ESPEN, E-ISSN 2405-4577, Vol. 58, p. 193-200Article in journal (Refereed)
    Abstract [en]

    Background & aims: Insulin resistance and chronic inflammation have been reported in patients with cancer. However, many of the underlying mechanisms and associations are yet to be unveiled. We examined both the level of insulin sensitivity and markers of inflammation in patients with colorectal cancer for comparison to controls.

    Methods: Clinical exploratory study of patients with colorectal cancer (n = 20) and matched controls (n = 10). Insulin sensitivity was quantified using the hyperinsulinemic normoglycemic clamp and blood samples were taken for quantification of several key, both intra- and extracellular, inflammatory markers. We analysed the differences in these parameters between the two groups.

    Results: Patients exhibited both insulin resistance (M-value, patients median (Mdn) 4.57 interquartile range (IQR) 3.49-5.75; controls Mdn 5.79 (IQR 5.20-6.81), p = 0.049), as well as increased plasma levels of the pro-inflammatory cytokines IL-1b(patients Mdn 0.48 (IQR 0.33-0.58); controls Mdn 0.36 (IQR 0.29-0.42), p = 0.02) and IL-6 (patients Mdn 3.21 (IQR 2.31-4.93); controls Mdn 2.16 (IQR 1.50-2.65), p = 0.02). The latter is present despite an almost two to three fold decrease (p < 0.01) in caspase-1 activity, a facilitating enzyme of IL-1b production, within circulating immune cells.

    Conclusion: Patients with colorectal cancer displayed insulin resistance and higher levels of plasma IL-1b and IL-6, in comparison to matched healthy controls. The finding of a seemingly disconnect between inflammasome (caspase-1) activity and plasma levels of key pro-inflammatory cytokines in cancer patients may suggest that, in parallel to dysregulated immune cells, tumour-driven inflammatory pathways also are in effect.

  • 10.
    Jendeberg, Johan
    et al.
    Örebro University, School of Medical Sciences.
    Cierzniak, B.
    Alshamari, Muhammed
    Örebro University, School of Medical Sciences. Örebro University Hospital.
    Geijer, Håkan
    Örebro University, School of Medical Sciences.
    Lidén, Mats
    Örebro University, School of Medical Sciences.
    Prognosis of spontaneous ureteral stone passage: as revealed by CT2016Conference paper (Refereed)
  • 11.
    Jendeberg, Johan
    et al.
    Örebro University, School of Medical Sciences. Department of Radiology.
    Geijer, Håkan
    Örebro University, School of Medical Sciences. Department of Radiology.
    Alshamari, Muhammed
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology.
    Cierzniak, Bartosz
    Department of Surgery, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Lidén, Mats
    Örebro University, School of Medical Sciences. Department of Radiology.
    Size matters: The width and location of a ureteral stone accurately predict the chance of spontaneous passage2017In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 27, no 11, p. 4775-4785Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To determine how to most accurately predict the chance of spontaneous passage of a ureteral stone using information in the diagnostic non-enhanced computed tomography (NECT) and to create predictive models with smaller stone size intervals than previously possible.

    METHODS: Retrospectively 392 consecutive patients with ureteric stone on NECT were included. Three radiologists independently measured the stone size. Stone location, side, hydronephrosis, CRP, medical expulsion therapy (MET) and all follow-up radiology until stone expulsion or 26 weeks were recorded. Logistic regressions were performed with spontaneous stone passage in 4 weeks and 20 weeks as the dependent variable.

    RESULTS: The spontaneous passage rate in 20 weeks was 312 out of 392 stones, 98% in 0-2 mm, 98% in 3 mm, 81% in 4 mm, 65% in 5 mm, 33% in 6 mm and 9% in ≥6.5 mm wide stones. The stone size and location predicted spontaneous ureteric stone passage. The side and the grade of hydronephrosis only predicted stone passage in specific subgroups.

    CONCLUSION: Spontaneous passage of a ureteral stone can be predicted with high accuracy with the information available in the NECT. We present a prediction method based on stone size and location.

    KEY POINTS: • Non-enhanced computed tomography can predict the outcome of ureteral stones. • Stone size and location are the most important predictors of spontaneous passage. • Prediction models based on stone width or length and stone location are introduced. • The observed passage rates for stone size in mm-intervals are reported. • Clinicians can make better decisions about treatment.

  • 12.
    Jendeberg, Johan
    et al.
    Örebro University, School of Medical Sciences. Department of Radiology.
    Geijer, Håkan
    Örebro University, School of Medical Sciences. Department of Radiology.
    Alshamari, Muhammed
    Örebro University, School of Medical Sciences. Örebro University Hospital. Department of Radiology.
    Lidén, Mats
    Örebro University, School of Medical Sciences. Department of Radiology.
    Prediction of spontaneous ureteral stone passage: Automated 3D-measurements perform equal to radiologists, and linear measurements equal to volumetric2018In: European Radiology, ISSN 0938-7994, E-ISSN 1432-1084, Vol. 28, no 6, p. 2474-2483Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES: To compare the ability of different size estimates to predict spontaneous passage of ureteral stones using a 3D-segmentation and to investigate the impact of manual measurement variability on the prediction of stone passage.

    METHODS: We retrospectively included 391 consecutive patients with ureteral stones on non-contrast-enhanced CT (NECT). Three-dimensional segmentation size estimates were compared to the mean of three radiologists' measurements. Receiver-operating characteristic (ROC) analysis was performed for the prediction of spontaneous passage for each estimate. The difference in predicted passage probability between the manual estimates in upper and lower stones was compared.

    RESULTS: The area under the ROC curve (AUC) for the measurements ranged from 0.88 to 0.90. Between the automated 3D algorithm and the manual measurements the 95% limits of agreement were 0.2 ± 1.4 mm for the width. The manual bone window measurements resulted in a > 20 percentage point (ppt) difference between the readers in the predicted passage probability in 44% of the upper and 6% of the lower ureteral stones.

    CONCLUSIONS: All automated 3D algorithm size estimates independently predicted the spontaneous stone passage with similar high accuracy as the mean of three readers' manual linear measurements. Manual size estimation of upper stones showed large inter-reader variations for spontaneous passage prediction.

    KEY POINTS:• An automated 3D technique predicts spontaneous stone passage with high accuracy.• Linear, areal and volumetric measurements performed similarly in predicting stone passage.• Reader variability has a large impact on the predicted prognosis for stone passage.

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