Cited by 120Bone health and osteoporosis researchMedical Imaging and AnalysisScoliosis diagnosis and treatment

Automatic opportunistic osteoporosis screening in routine CT: improved prediction of patients with prevalent vertebral fractures compared to DXA

Open access
Löffler, Maximilian T., Jacob, Alina, Scharr, Andreas, Sollmann, Nico, Burian, Egon, El Husseini, Malek, Sekuboyina, Anjany, Tetteh, Giles +4 more·2021·European Radiology

Abstract

Objectives: To compare spinal bone measures derived from automatic and manual assessment in routine CT with dual energy X-ray absorptiometry (DXA) in their association with prevalent osteoporotic vertebral fractures using our fully automated framework (https://anduin.bonescreen.de) to assess various bone measures in clinical CT. Methods: We included 192 patients (141 women, 51 men; age 70.2 ± 9.7 years) who had lumbar DXA and CT available (within 1 year). Automatic assessment of spinal bone measures in CT included segmentation of vertebrae using a convolutional neural network (CNN), reduction to the vertebral body, and extraction of bone mineral content (BMC), trabecular and integral volumetric bone mineral density (vBMD), and CT-based areal BMD (aBMD) using asynchronous calibration. Moreover, trabecular bone was manually sampled (manual vBMD). Results: A total of 148 patients (77%) had vertebral fractures and significantly lower values in all bone measures compared to patients without fractures (p ≤ 0.001). Except for BMC, all CT-based measures performed significantly better as predictors for vertebral fractures compared to DXA (e.g., AUC = 0.885 for trabecular vBMD and AUC = 0.86 for integral vBMD vs. AUC = 0.668 for DXA aBMD, respectively; both p < 0.001). Age- and sex-adjusted associations with fracture status were strongest for manual vBMD (OR = 7.3, [95%] CI 3.8–14.3) followed by automatically assessed trabecular vBMD (OR = 6.9, CI 3.5–13.4) and integral vBMD (OR = 4.3, CI 2.5–7.6). Diagnostic cutoffs of integral vBMD for osteoporosis (< 160 mg/cm 3) or low bone mass (160 ≤ BMD < 190 mg/cm 3) had sensitivity (84%/41%) and specificity (78%/95%) similar to trabecular vBMD. Conclusions: Fully automatic osteoporosis screening in routine CT of the spine is feasible. CT-based measures can better identify individuals with reduced bone mass who suffered from vertebral fractures than DXA. Key Points: • Opportunistic osteoporosis screening of spinal bone measures derived from clinical routine CT is feasible in a fully automatic fashion using a deep learning-driven framework (https://anduin.bonescreen.de). • Manually sampled volumetric BMD (vBMD) and automatically assessed trabecular and integral vBMD were the best predictors for prevalent vertebral fractures. • Except for bone mineral content, all CT-based bone measures performed significantly better than DXA-based measures. • We introduce diagnostic thresholds of integral vBMD for osteoporosis (< 160 mg/cm3) and low bone mass (160 ≤ BMD < 190 mg/cm3) with almost equal sensitivity and specificity compared to conventional thresholds of quantitative CT as proposed by the American College of Radiology (osteoporosis < 80 mg/cm3).

AI snapshot

Written from the paper’s full text.

TL;DR

This retrospective study compared fully automatic CT-derived spinal bone measures with DXA for identifying prevalent osteoporotic vertebral fractures in 192 patients. CT-based volumetric measures, especially trabecular and integral vBMD, predicted prevalent fractures better than DXA, and the authors propose integral vBMD thresholds for osteoporosis and low bone mass.

Key findings

  • Among 192 patients (141 women, 51 men; mean age 70.2 ± 9.7 years), 148 (77%) had at least one prevalent vertebral fracture; fractured patients were older (72.0 ± 9.3 vs. 64.3 ± 8.6 years, p < 0.001) and had significantly lower values in all bone measures (p ≤ 0.001).
  • Except for BMC, all CT-based measures predicted prevalent vertebral fractures significantly better than DXA aBMD: AUC = 0.885 for trabecular vBMD, 0.86 for integral vBMD, and 0.894 for manual vBMD vs. 0.668 for DXA aBMD (p < 0.001 for vBMD comparisons); CT-based BMC was not significantly different from DXA aBMD or T-score.
  • Age- and sex-adjusted associations with fracture status were strongest for manual vBMD (OR = 7.3, 95% CI 3.8–14.3), followed by automatically assessed trabecular vBMD (OR = 6.9, CI 3.5–13.4) and integral vBMD (OR = 4.3, CI 2.5–7.6); DXA T-score and aBMD each had OR = 1.9 (CI 1.3–2.8).
  • Proposed integral vBMD thresholds were osteoporosis < 160 mg/cm³ and low bone mass 160 ≤ BMD < 190 mg/cm³, with sensitivity/specificity of 84%/78% and 41%/95%, respectively, similar to trabecular vBMD (86%/78% and 41%/98%).

Methods

  • Monocentric retrospective study: 360 patients were identified, exclusions left 192 with lumbar DXA and CT available within 1 year; prevalent vertebral fractures were classified using the Genant semiquantitative technique (grade ≥ 1).
  • CT bone measures used a fully automatic framework: CNN-based vertebral segmentation, reduction to vertebral bodies, asynchronous HU-to-BMD calibration with contrast correction, and extraction of integral vBMD, trabecular vBMD (eroded by 5 mm), BMC, and CT-based aBMD; manual trabecular vBMD was also sampled.
  • Statistical analysis used t tests and chi-squared tests for group comparisons, logistic regression for odds ratios per 1 SD change (unadjusted and age/sex-adjusted), and ROC AUC analysis with DeLong’s test for correlated ROC curves; significance was p < 0.05.

Limitations

  • Stated: retrospective selection bias toward elderly, mainly neurosurgical and oncological patients who already had both CT and DXA within 1 year, meaning osteoporosis was already suspected; the study assessed prevalent, not incident, vertebral fractures, so the new integral vBMD thresholds require validation in follow-up fracture-risk studies.
  • Evident: the single-center design and high fracture prevalence (77%) may limit generalizability, and the automatic framework and proposed thresholds were not externally validated in this paper.

Model-written summary. Check it against the paper before relying on it.

Integrity signals

Registry

Crossref · 10.1007/s00330-020-07655-2

Cites

42 of 42 references verified0 citation errors · 0 not checkable

Statistics

Nothing to recompute.

Claims the paper makes

8 of 20 cited sources checked · 3 supported · 1 flagged · accuracy not yet measured

  • Premisecitation

    A framework for fully automatic segmentation of vertebrae in any CT dataset within several seconds was recently introduced.

    “We recently introduced a framework for fully automatic segmentation of vertebrae in any CT dataset within several seconds [16, 17].”
    Quote in the paperSubstantial claim1 of 2 sources checked
    • cites [16] Löffler MT, Sekuboyina A, Jacob A et al (2020) A vertebral segmentation dataset with fracture grading. Radiol Artif Intell 2:e190138. https://doi.org/10.1148/ryai.2020190138 source

      The Materials and Methods section (Vertebral Segmentation; page unavailable) describes a framework that predicts vertebral segmentations from CT images. It does not establish that the framework works on any CT dataset or completes segmentation within several seconds, and the dataset’s final masks were manually refined. (LLM, conf=0.87)

      Experimental — accuracy not yet measured
    • cites [17] Sekuboyina A, Bayat A, Husseini ME et al (2020) VerSe: a vertebrae labelling and segmentation benchmark. arXiv:200109193 [cs, eess]

      Couldn’t be matched to a paper in Crossref, so it can’t be checked.

  • Findingown data

    All bone measures were statistically significant predictors of prevalent vertebral fractures in AUC analysis.

    “AUC analysis showed that all bone measures were statistically significant predictors of prevalent vertebral fractures (Table 3, Fig. 4).”
    Quote in the paperNot a substantial claim
  • Findingown data

    CT-based BMC showed no significant difference in discriminatory power compared to DXA-based aBMD or T-score (AUC = 0.735 vs 0.668 or 0.67).

    “Only CT-based BMC showed no significant difference in discriminatory power to DXA-based aBMD or T-score (AUC = 0.735 vs. 0.668 or 0.67, respectively).”
    Quote in the paperNot a substantial claim
  • Findingown data

    CT-based aBMD slightly underestimated aBMD compared to DXA (bias −0.054 and −0.015 g/cm2 at L2 and L3).

    “Bland-Altman plots showed a bias of − 0.054 and − 0.015 g/cm2 at L2 and L3, respectively, for CT-based aBMD (Supplementary Fig. 1). Thus, CT-based assessment seemed to slightly underestimate aBMD compared to DXA.”
    Quote in the paperNot a substantial claim
  • Findingown data

    Except for BMC, all CT-based bone measures showed significantly better discriminatory power for the prevalence of vertebral fractures compared to DXA-based measures.

    “Except for BMC, all CT-based bone measures showed significantly better discriminatory power for the prevalence of vertebral fractures compared to DXA-based measures.”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim. 12
  • May combine two claims. 15
  • The quote only partly states this claim. 1
  • Classified as probably not a substantial claim.

    Premisecitation

    Previously published HU-to-BMD conversion equations were used for all CT scanners in this study.

    “Previously published HU-to-BMD conversion equations were used for all CT scanners in this study [22].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [22] Löffler MT, Jacob A, Valentinitsch A et al (2019) Improved prediction of incident vertebral fractures using opportunistic QCT compared to DXA. Eur Radiol. https://doi.org/10.1007/s00330-019-06018-w source

      The Methods (Opportunistic QCT) state that HU-to-BMD conversion equations were calculated by linear regression using phantom measurements for the scanners in this study. Table 4 (Results) lists the resulting scanner-specific equations. The paper does not describe using previously published conversion equations for all scanners; the previously investigated values mentioned in Methods are contrast-enhancement correction offsets. (LLM, conf=0.92)

      Checked by a reasoning model — may be wrong.

      Experimental — accuracy not yet measured
  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Vertebrae were automatically segmented in CT scans using a framework of CNNs that identifies the spine, labels each vertebral body, and creates segmentation masks.

    “First, vertebrae were automatically segmented in CT scans using a framework of CNNs that identifies the spine, labels each vertebral body, and creates segmentation masks [16].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [16] Löffler MT, Sekuboyina A, Jacob A et al (2020) A vertebral segmentation dataset with fracture grading. Radiol Artif Intell 2:e190138. https://doi.org/10.1148/ryai.2020190138 source
  • Classified as probably not a substantial claim. May combine two claims.

    Premisecitation

    Besides hip fractures, vertebral fractures are the most common and most consequential osteoporotic fractures.

    “Besides hip fractures, vertebral fractures are the most common and most consequential osteoporotic fractures [4].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [4] Ensrud KE (2013) Epidemiology of fracture risk with advancing age. J Gerontol A Biol Sci Med Sci 68:1236–1242. https://doi.org/10.1093/gerona/glt092 source

      The Vertebral Fractures section calls vertebral fractures the most common manifestation of osteoporosis and describes associations with pain, disability, mortality, and subsequent fractures. It does not establish that they are the most consequential after hip fractures; it reports that clinical vertebral fractures accounted for only 6% of fracture-related costs in the United States in 2005. (LLM, conf=0.84)

      Experimental — accuracy not yet measured
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    Differences in the study population, focus on prevalent instead of incident fractures, and better sensitivity to detect fractures by using ≤1-mm instead of 2.5-mm axial slices could lead to relatively higher ORs compared to Allaire et al.

    “These differences in the study population—paired with the focus on prevalent instead of incident fractures and better sensitivity to detect fractures by using ≤ 1-mm instead of 2.5-mm axial slices [26]—could lead to the relatively higher ORs compared to Allaire et al (OR = 2.7 vs. 1.6 for CT-based aBMD, OR = 4.8 vs. 2.8 for integral vBMD, and OR = 6.8 vs. 2.1 for trabecular vBMD) [27]; though, CT–”
    Quote in the paperNot a substantial claim1 of 2 sources checked
    • cites [26] Bauer JS, Müller D, Ambekar A et al (2006) Detection of osteoporotic vertebral fractures using multidetector CT. Osteoporos Int 17:608–615. https://doi.org/10.1007/s00198-005-0023-8 source
    • cites [27] Allaire BT, Lu D, Johannesdottir F et al (2019) Prediction of incident vertebral fracture using CT-based finite element analysis. Osteoporos Int 30:323–331. https://doi.org/10.1007/s00198-018-4716-1 source

      The Methods and Results identify Allaire et al.’s study as examining incident vertebral fractures, and the Results report an OR of 1.6 for CT-based aBMD. Our copy says integral and trabecular vBMD were associated with incident fracture, but the passages do not give the specific ORs of 2.8 and 2.1 attributed to Allaire et al. The proposed reasons for the higher ORs are the citing authors’ interpretation; the slice-thickness comparison is attached to a different citation. (LLM, conf=0.82)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Premisecitation

    There is significant variability in access to DXA services and many fall short of international quality standards.

    “Second, there is significant variability in the access to DXA services and many fall short of international quality standards [14].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [14] Clynes MA, Westbury LD, Dennison EM et al (2020) Bone densitometry worldwide: a global survey by the ISCD and IOF. Osteoporos Int 31:1779–1786. https://doi.org/10.1007/s00198-020-05435-8 source
  • Classified as probably not a substantial claim.

    Premisecitation

    Bias of BMD values due to intravenous injection of contrast medium was corrected for using linear correction equations for arterial and portal/venous contrast phases.

    “Bias of BMD values due to intravenous injection of contrast medium was corrected for using linear correction equations for arterial and portal/venous contrast phases [23].”
    Quote in the paperSubstantial claim1 of 1 sources checked
    • cites [23] Kaesmacher J, Liebl H, Baum T, Kirschke JS (2017) Bone mineral density estimations from routine multidetector computed tomography: a comparative study of contrast and calibration effects. J Comput Assist Tomogr 41:217–223. https://doi.org/10.1097/RCT.0000000000000518 source
  • May combine two claims.

    Findingcitation

    Compared to a study of incident vertebral fractures in the MrOS cohort, the AUCs reported here are higher for trabecular vBMD (0.885 vs 0.79) but lower for DXA-based aBMD (0.668 vs 0.72).

    “Compared to a study of incident vertebral fractures in the Osteoporotic Fractures in Men (MrOS) Study cohort of elderly men, the AUCs we report seem considerably higher for trabecular vBMD (AUC = 0.885 vs. 0.79), but lower for DXA-based aBMD (AUC = 0.668 vs. 0.72) [28].”
    Quote in the paperNot a substantial claim1 of 1 sources checked
    • cites [28] Chalhoub D, Orwoll ES, Cawthon PM et al (2016) Areal and volumetric bone mineral density and risk of multiple types of fracture in older men. Bone 92:100–106. https://doi.org/10.1016/j.bone.2016.08.014 source

      The Discussion (page unavailable) identifies this as a MrOS study and reports that trabecular spine vBMD predicted spine fractures better than DXA-based spine aBMD. The cited paper passages do not give the specific AUCs of 0.79 and 0.72, so those numerical comparisons are not verified by our copy. (LLM, conf=0.78)

      Experimental — accuracy not yet measured
  • May combine two claims.

    Findingown data

    Age- and sex-adjusted association with fracture status was strongest for manual vBMD (OR = 7.3, 95% CI 3.8-14.3), followed by automatically assessed trabecular vBMD (OR = 6.9, 95% CI 3.5-13.4) and integral vBMD (OR = 4.3, 95% CI 2.5-7.6).

    “Age- and sex-adjusted associations with fracture status were strongest for manual vBMD (OR = 7.3, [95%] CI 3.8–14.3) followed by automatically assessed trabecular vBMD (OR = 6.9, CI 3.5–13.4) and integral vBMD (OR = 4.3, CI 2.5–7.6).”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    All automatically assessed CT-based bone measures had a highly significant association with the prevalence of osteoporotic vertebral fractures, with no significant differences between automatic and manual measurements.

    “All automatically assessed CT-based bone measures had a highly significant association with the prevalence of osteoporotic vertebral fractures with no significant differences between automatic and manual measurements.”
    Quote in the paperSubstantial claim
  • May combine two claims.

    Findingown data

    Patients with vertebral fractures had significantly lower values in all bone measures (DXA-based aBMD, CT-based aBMD, manual vBMD, trabecular vBMD, integral vBMD, and BMC, p < 0.001 each; DXA-based T-score, p = 0.001) compared to patients without fractures.

    “and showed significantly lower values in all bone measures (DXA-based aBMD, CT-based aBMD, manual vBMD, trabecular vBMD, integral vBMD, and BMC, p < 0.001 each; DXA-based T-score, p = 0.001) compared to patients without fractures”
    Quote in the paperSubstantial claim
  • Classified as probably not a substantial claim.

    Findingown data

    The study included 192 patients (141 women, 51 men; mean age 70.2 ± 9.7 years) who had lumbar DXA and CT available within 1 year.

    “We included 192 patients (141 women, 51 men; age 70.2 ± 9.7 years) who had lumbar DXA and CT available (within 1 year).”
    • Also stated in: § Results · plain
      “Overall, 192 patients (141 women, 51 men) with a mean age of 70.2 ± 9.7 years were included in this study.”
    Quote in the paperSubstantial claim
  • May combine two claims. The quote only partly states this claim.

    Findingown data

    Most CT-based measures performed significantly better than DXA in AUC for predicting prevalent vertebral fractures; e.g., DXA-based aBMD AUC = 0.668 vs integral vBMD 0.860, trabecular vBMD 0.885, manual vBMD 0.894, p < 0.001 each.

    “However, most CT-based measures performed significantly better than DXA, e.g., when comparing DXA-based aBMD with intergral, trabecual, or manual vBMD (AUC = 0.668 vs. 0.735, 0.860, or 0.885, respectively, p < 0.001 each; Table 3).”
    Quote in the paperSubstantial claim
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Interpretationreasoning

    The high prevalence of at least mild (Genant grade 1) osteoporotic vertebral fractures (77%) is not surprising because all patients received DXA scans, implicating that osteoporosis was already suspected.

    “We reported on elderly patients that all received DXA scans, thereby implicating that osteoporosis was already suspected; thus, the high prevalence of at least mild (Genant grade 1) osteoporotic vertebral fractures (77%) is not surprising.”
    Quote in the paperNot a substantial claim
  • May combine two claims.

    Premisecitation

    Opportunistic quantitative evaluation of preexisting clinical routine CT entails neither additional costs nor radiation exposure.

    “Opportunistic quantitative evaluation of preexisting clinical routing CT entails neither additional costs nor radiation exposure [15].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [15] Löffler MT, Sollmann N, Mei K et al (2020) X-Ray-based quantitative osteoporosis imaging at the spine. Osteoporos Int 31:233–250. https://doi.org/10.1007/s00198-019-05212-2 source
  • Classified as probably not a substantial claim.

    Study design and conductcitation

    CT scans were screened for prevalent osteoporotic vertebral fractures using the semi-quantitative technique by Genant.

    “CT scans of the remaining 258 patients were screened for prevalent osteoporotic vertebral fractures using the semi-quantitative technique by Genant [18].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [18] Genant HK, Wu CY, van Kuijk C, Nevitt MC (1993) Vertebral fracture assessment using a semiquantitative technique. J Bone Miner Res 8:1137–1148. https://doi.org/10.1002/jbmr.5650080915 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductnone given

    The local institutional review board approved the monocentric retrospective study and waived written informed consent.

    “The local institutional review board approved this monocentric retrospective study (ethics committee’s reference number 27/19S/SR) and waived written informed consent.”
    Quote in the paperNot a substantial claim
  • Classified as probably not a substantial claim.

    Premisecitation

    The standard screening method includes assessing clinical risk factors and measuring areal bone mineral density (aBMD) using dual-energy X-ray absorptiometry (DXA).

    “To date, the standard screening method includes assessing clinical risk factors and measuring areal bone mineral density (aBMD) using dual-energy X-ray absorptiometry (DXA) [1].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [1] NIH Consensus Development Panel on Osteoporosis Prevention, Diagnosis, and Therapy (2001) Osteoporosis prevention, diagnosis, and therapy. JAMA 285:785–795 source
  • Classified as probably not a substantial claim.

    Premisecitation

    For trabecular vBMD, the diagnostic thresholds for osteoporosis (BMD < 80 mg/cm3) and for low bone mass (80 ≤ BMD ≤ 120 mg/cm3) proposed by the American College of Radiology (ACR) were used.

    “For trabecular vBMD, we used the diagnostic thresholds for osteoporosis (BMD < 80 mg/cm3) and for low bone mass (80 ≤ BMD ≤ 120 mg/cm3) proposed by the American College of Radiology (ACR) [24].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [24] American College of Radiology (2018) ACR–SPR–SSR practice parameter for the performance of musculoskeletal quantitative computed tomography (QCT). American College of Radiology, Reston. Available via https://www.acr.org/-/media/ACR/Files/Practice-Parameters/QCT.pdf?la=en. Accessed 7 Nov 2018

      Not checked in the free run.

  • May combine two claims.

    Premisecitation

    Less than half of women (44%) and even fewer men (21%) with osteoporotic fractures exhibited low aBMD in a large observational study.

    “First, less than half of women (44%) and even fewer men (21%) with osteoporotic fractures exhibited low aBMD in a large observational study [12]”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [12] Schuit SCE, van der Klift M, Weel AEAM et al (2004) Fracture incidence and association with bone mineral density in elderly men and women: the Rotterdam Study. Bone 34:195–202 source
  • Probably not a substantial claim: may not pass S3 (load-bearing). May combine two claims.

    Study design and conductcitation

    DXA scans were performed by trained technologists and quality was assured through evaluation by experienced physicians following current recommendations.

    “Scans were performed by trained technologists and quality was assured through evaluation by experienced physicians following current recommendations [19].”
    Quote in the paperNot a substantial claim0 of 1 sources checked
    • cites [19] Shepherd JA, Schousboe JT, Broy SB, Engelke K, Leslie WD (2015) Executive summary of the 2015 ISCD Position Development Conference on Advanced Measures From DXA and QCT: fracture prediction beyond BMD. J Clin Densitom 18:274–286. https://doi.org/10.1016/j.jocd.2015.06.013 source
  • May combine two claims.

    Premisecitation

    Quantitative computed tomography (QCT) has limited availability, is more expensive, and is associated with a substantially higher radiation dose (>100-fold).

    “Yet, other methods of bone densitometry exhibit even more disadvantages: quantitative computed tomography (QCT) has limited availability, is more expensive, and is associated with a substantially higher radiation dose (> 100-fold) [15].”
    Quote in the paperSubstantial claim0 of 1 sources checked
    • cites [15] Löffler MT, Sollmann N, Mei K et al (2020) X-Ray-based quantitative osteoporosis imaging at the spine. Osteoporos Int 31:233–250. https://doi.org/10.1007/s00198-019-05212-2 source
21 of 21
  • The authors state this as an assumption.

    CT-based aBMD has superior accuracy to DXA because of the 3-dimensional character of CT scans, despite being a monoenergetic technique.

    “We chose this approach to take advantage of the 3-dimensional character of CT scans compared to DXA, thus postulating its superior accuracy notwithstanding the fact that it is a monoenergetic technique.”
1 of 1

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

Each contradiction between two passages listed here was confirmed by an independent check.

  • AUCs are assigned to the wrong CT measures

    Minor

    The results assign AUCs of 0.735, 0.860, and 0.885 to integral, trabecular, and manual vBMD, respectively. Table 3 instead reports 0.86, 0.885, and 0.894 for those measures; 0.735 belongs to BMC.

  • A T-score of −2.5 is classified as both low bone mass and osteoporosis

    Minor

    The methods define osteoporosis as T ≤ −2.5 SD, but the Fig. 2 caption calls a T-score of −2.5 SD low bone mass.

2 of 2

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Authors
Löffler, M. T., Jacob, A., Scharr, A., Sollmann, N., Burian, E., El Husseini, M., Sekuboyina, A., Tetteh, G., Zimmer, C., Gempt, J., Baum, T., & Kirschke, J. S.
Affiliations
  • University of Freiburg (DE)
  • TUM Klinikum (DE)
  • Technical University of Munich (DE)
Corresponding author
Löffler, Maximilian T.
Venue
European Radiology
Published
2021-01-28
Volume
31
Issue
8
Pages
6069-6077
ISSN
  • 0938-7994 (ISSN-L)
  • 1432-1084
OpenAlex
W3121936649
Cited by
120
References
42
Citations by year
2026: 15 · 2025: 27 · 2024: 20 · 2023: 32 · 2022: 20 · 2021: 5 · 2020: 1
FWCI
16.99
Type
journal article
Language
en
Open access
Locations
  • European Radiology (publishedVersion, cc-by)
  • PubMed (publishedVersion)
  • PubMed Central (submittedVersion, cc-by)
  • Informationszentrum Lebenswissenschaften (ZB MED) (submittedVersion, cc-by)
  • mediaTUM – the media and publications repository of the Technical University Munich (Technical University Munich) (submittedVersion, other-oa)
  • mediaTUM – the media and publications repository of the Technical University Munich (Technical University Munich) (submittedVersion)
  • OPen Access Repositorium der Universität Ulm (OPARU) (Ulm University) (submittedVersion, cc-by)
  • Universität Ulm, Kommunikations- und Informationszentrum (kiz) (cc-by)
Funders
  • European Research Council (637164)
  • Deutsche Forschungsgemeinschaft (432290010)
Topics
  • Health Sciences › Medicine › Orthopedics and Sports Medicine › Bone health and osteoporosis research
  • Physical Sciences › Engineering › Biomedical Engineering › Medical Imaging and Analysis
  • Health Sciences › Medicine › Surgery › Scoliosis diagnosis and treatment
Keywords
osteoporosis screening, vertebral fractures, dual-energy X-ray absorptiometry, volumetric bone mineral density, trabecular bone, bone mineral content, vertebral segmentation, convolutional neural networks, osteopenia, fracture prediction, low-dose CT, diagnostic accuracy
MeSH terms
Aged, Female, Humans, Lumbar Vertebrae, Male, Middle Aged, Osteoporosis, Tomography, X-Ray Computed, Absorptiometry, Photon, Bone Density, Spinal Fractures

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