Radiation dose by spiral CT and conventional tomography of the sternoclavicular joints and the manubrium sterni

Age assessment in unaccompanied minors: assessing uniformity of protocols across Europe

Age assessment of migrants is crucial, particularly for unaccompanied foreign minors, a population facing legal, social, and humanitarian challenges. Despite existing guidelines, there is no unified protocol in Europe for age assessment.The Forensic Anthropology Society of Europe (FASE) conducted a comprehensive questionnaire to understand age estimation practices in Europe. The questionnaire had sections focusing on the professional background of respondents, annual assessment numbers, requesting parties and reasons, types of examinations conducted (e.g., physical, radiological), followed protocols, age estimation methods, and questions on how age estimates are reported.The questionnaire's findings reveal extensive engagement of the forensic community in age assessment in the living, emphasizing multidisciplinary approaches. However, there seems to be an incomplete appreciation of AGFAD guidelines. Commonalities exist in examination methodologies and imaging tests. However, discrepancies emerged among respondents regarding sexual maturity assessment and reporting assessment results. Given the increasing importance of age assessment, especially for migrant child protection, the study stresses the need for a unified protocol across European countries. This can only be achieved if EU Member States wholeheartedly embrace the fundamental principles outlined in EU Directives and conduct medical age assessments aligned with recognized standards such as the AGFAD guidelines.

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

PURPOSE

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.

RESULTS

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.

CONCLUSION

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.

Digital tomography is an effective investigation for sternoclavicular joint pathology

OBJECTIVE

Plain radiographs of the sternoclavicular joint (SCJ) are difficult to interpret, and a CT or MRI scan is the usual investigation of choice. At our hospital, we use digital SCJ tomograms as our first-line investigation for all SCJ pathologies. We wanted to ascertain whether this is a safe and appropriate first-line imaging investigation.

MATERIALS AND METHODS

We retrospectively reviewed every patient who had undergone an SCJ digital tomogram (DT) over a 4-year period. We cross-referenced each patient with their records to assess the reason for referral, result, requirement for further investigation, diagnosis and management.

RESULTS

We identified 132 SCJ tomograms over the study period. Twelve patients were referred from other hospitals with pre-existing imaging and were excluded. The reasons for radiological investigation in the remaining 120 patients were pain/lump without trauma (54.2%), pain/lump with trauma (30.8%) and post-operative review (15%). Of the 102 patients who had DT as their initial investigation, the most common diagnoses identified included osteoarthritis, normal SCJ, fracture and dislocation among others. Only 18 (17.6%) of these patients required further investigation with CT and/or MRI.

CONCLUSION

Our study is the first to assess digital tomography in SCJ pathology. We have shown that digital tomograms are an accurate and economically beneficial investigation for SCJ pathology and propose that it should be used as a first-line imaging investigation.

Magnetic resonance imaging of the medial extremity of the clavicle in forensic bone age determination: a new four-minute approach

OBJECTIVES

The use of 3T magnetic resonance imaging (MRI) of the clavicle in forensic bone age determination was prospectively examined and compared with plain radiography.

METHODS

Four MRI sequences and three radiographs of 121 healthy subjects between 11 and 30 were studied by two observers.

RESULTS

The number of images assessable for bone age determination was lower for plain radiography (PA: 68.7%; oblique: 97.5%) compared with MRI (VIBE: 99.0%). Concerning the subjective level of difficulty to assess bone age, the observers found it easier to assess bone age on MRI than on radiography. The developmental stages of the clavicle, as used on plain radiography, were transferable to MRI. Especially the VIBE gradient echo sequence provided an excellent depiction of the growth cartilage and ossification centre with a slice thickness of 0.9 mm and only a 4-min acquisition time. When the developmental stages were assigned, less variability between the observers was seen on MRI, compared with plain radiography.

CONCLUSION

We conclude that 3T MRI provides high resolution, cross-sectional images of the maturation of the clavicle without ionising radiation in a very short time, allowing more accurate determination of bone age than plain radiography.

The influence of slice thickness on assessment of clavicle ossification in forensic age diagnostics

Computed tomography scans originally obtained to assess the ossification status of the medial clavicular epiphyses of 40 live subjects for forensic age estimation purposes were analysed. From the data acquired we reconstructed images with slice thicknesses of 1, 3, 5 and 7 mm, and based on the classification of stages by Schmeling et al. (Int J Legal Med 118:5-8, 2004), we determined the ossification stage for each reconstructed slice thickness, separately for both sides. Of the 80 clavicular epiphysial plates examined, seven displayed slice-thickness-dependent differences at certain ossification stages. In one case a slice thickness of 1 mm led to a different diagnosis of the ossification stage than a slice thickness of 3 mm, in three cases the diagnoses differed between the slice thicknesses of 3 and of 5 mm, and in another three cases, between 5 and 7 mm. We therefore conclude that for age estimation purposes, the slice thickness should be 1 mm to ensure maximum accuracy and diagnostic reliability.

A positron emission tomography/computed tomography (PET/CT) acquisition protocol for CT radiation dose optimization

BACKGROUND

In current combined positron emission tomography/computed tomography (PET/CT) systems, high-quality CT images not only increase diagnostic value by providing anatomic delineation of hyper- and hypometabolic tissues, but also shorten the acquisition time for attenuation correction compared with standard PET imaging. However, this technique potentially introduces more radiation burden to patients as a result of the higher radiation exposure from CT.

METHODS

In this study, the radiation doses delivered from typical germanium-based and CT-based transmission scans were measured and compared using an anthropomorphic Rando Alderson phantom with insertions of thermoluminescent dosimeters. Image geometric distortion and quantified uptake values in PET images with different manipulating CT acquisition protocols for attenuation correction were also evaluated.

RESULTS

It was found that radiation doses during germanium-based transmission scans were almost negligible, while doses from CT-based transmission scans were significantly higher. Using a lower radiation dose, the CT acquisition protocol did not significantly affect attenuation correction and anatomic delineation in PET.

CONCLUSIONS

This study revealed the relation between image information and dose. The current PET/CT imaging acquisition protocol was improved by decreasing the radiation risks without sacrificing the diagnostic values.

CT angiography of thoracic outlet syndrome: evaluation of imaging protocols for the detection of arterial stenosis

PURPOSE

The purpose of this work was to evaluate the results of cross-sectional imaging and multiplanar and 3D reconstructions for the detection of thoracic outlet arterial stenosis on CT angiograms.

METHOD

Eighty-two patients were prospectively evaluated with CT angiography: in the neutral position and after postural maneuver (164 acquisitions); with contralateral injection of a 24% (Group 1; n = 68) or 30% (Group 2; n = 96) contrast agent; and reconstruction of four sets of images from each acquisition, that is, transverse CT scans, sagittal reformations, and 3D [shaded surface displays (SSD) and volume-rendered (VR)] images. A total of 656 sets of images were blindly and independently interpreted by three readers of variable experience. A consensus interpretation of the four sets of images of each acquisition was used as a standard of reference.

RESULTS

The number of examinations coded with an excellent degree of arterial enhancement was significantly higher in Group 2 than in Group 1 [68 (71%) vs. 35 (51%); p < 0.001]. The sensitivity and specificity for detection of arterial stenosis were 67 and 96% for transverse CT scans, 69 and 94% for sagittal reformations, 71 and 99% for 3D-SSDs, and 95 and 100% for VR images. Compared with the standard of reference, a concordant scoring of arterial stenosis severity was found in 54% of transverse CT scans, 84% of sagittal reformations, 78% of 3D-SSDs, and 91% of VR images. Underestimation of stenosis was found in 43% of transverse CT scans and 10% of sagittal reformations; overestimation of stenosis was more frequent on 3D-SSDs (16%) than on VR images (7%). The reader's experience was marked for the interpretation of cross-sectional images but did not influence the interpretation of 3D images.

CONCLUSION

Thoracic outlet arterial compression is best depicted with the injection of a 30% contrast agent and reconstruction of VR images.