Comparison of different iterative CT reconstruction techniques and filtered back projection for assessment of the medial clavicular epiphysis in forensic age estimation

  • Magdalini TozakidouEmail author
  • Ilze Apine
  • Kay U. Petersen
  • Julius Matthias Weinrich
  • Sebastian Schindera
  • Eilin Jopp-van Well
  • Klaus Püschel
  • Jochen Herrmann
Original Article



To assess the impact of iterative reconstruction and filtered back projection (FBP) on image quality in computed tomography (CT)-based forensic age estimation of the medial clavicular epiphysis.

Methods and materials

CT of the clavicle was performed in 19 patients due to forensic reasons (70 mAs/140 kVp). Raw data were reconstructed with FBP and with an iterative algorithm at level 4 and 6. Clavicular ossification stage was determined by two radiologists in consensus, firstly on FBP reconstructed images and secondly after reviewing all reconstructions including iDose 4 and 6. In addition, the 3 reconstructions were compared regarding artefacts and delineation of the meta-/epiphyseal interface. Quantitative image noise was measured.


Quantitative noise was lower in iDose 6 reconstructed images than in FBP (P < 0.042), but not significantly lower between iDose 4 and FBP (P = 0.127). Side by side comparison revealed lesser qualitative image noise on both iDose reconstructed images than for FBP. The meta-/epiphyseal interface delineation was rated better on both iDose levels than with FBP. In 3 of 19 patients, the clavicular ossification stage was reclassified after iterative reconstructions had been additionally reviewed.


Using iterative CT reconstruction algorithms, a reduction of image noise and an enhancement of image quality regarding the meta-/epiphyseal clavicular interface can be achieved. The study highlights the importance of image standardization as variation of reconstruction technique has impact on forensic age estimation.


Iterative reconstruction CT Forensic age estimation Clavicle 


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

This retrospective study was approved by the local ethics committee with waived informed consent due to the use of anonymized data.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Diagnostic and Interventional Radiology and Nuclear medicine, Section of Pediatric RadiologyUniversity Hospital Hamburg-EppendorfHamburgGermany
  2. 2.Children Clinical University HospitalRigaLatvia
  3. 3.Department of Psychiatry and PsychotherapyUniversity Hospital TübingenTübingenGermany
  4. 4.Department of Diagnostic and Interventional Radiology and Nuclear medicineUniversity Hospital Hamburg-EppendorfHamburgGermany
  5. 5.Cantonal Hospital AarauAarauSwitzerland
  6. 6.Department of Forensic MedicineUniversity Hospital Hamburg-EppendorfHamburgGermany

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