CT-like images based on T1-weighted gradient echo MRI sequences for the assessment of fractures of the hand and wrist compared to CT

OBJECTIVE

To evaluate the performance of a 3D T1-weighted gradient-echo (3D T1GRE) computed tomography (CT)-like magnetic resonance imaging (MRI) sequence for detecting and assessing wrist and hand fractures compared to conventional CT.

METHODS

Subjects with acute wrist or hand fracture in CT underwent additional 3 T MRI including a CT-like 3D T1GRE sequence and were compared to patients without fractures. Two radiologists assessed fracture morphology on both modalities according to the Arbeitsgemeinschaft Osteosynthese (AO) and graded image quality and diagnostic confidence on a 5-point Likert scale. Besides diagnostic test evaluation, differences in image quality and diagnostic confidence between CT-like MRI and CT were calculated using the Wilcoxon test. Agreement of AO classification between modalities and readers was assessed using Cohen's Kappa.

RESULTS

Twenty-eight patients with 43 fractures and 43 controls were included. Image quality (3D T1GRE 1.19 ± 0.37 vs. CT 1.22 ± 0.42; p = 0.65) and diagnostic confidence (3D T1GRE 1.28 ± 0.53 vs. CT 1.28 ± 0.55; p = 1.00) were rated excellent for both modalities. Regarding the AO classification, intra- (rater 1 and rater 2, κ = 0.89; 95% CI 0.80-0.97) and interrater agreement were excellent (3D T1GRE, κ = 0.82; 95% CI, 0.70-0.93; CT, κ = 0.85; 95% CI, 0.75-0.94). CT-like MRI showed excellent sensitivity, specificity and accuracy for fracture detection (reader 1: 1.00, 0.92, 0.96; reader 2: 0.98, 0.94, 0.96).

CONCLUSION

CT-like MRI is a comparable alternative to CT for assessing hand and wrist fractures, offering the advantage of avoiding radiation exposure.

[Pathologies of the shoulder joint : Anatomy and examination techniques]

CLINICAL ISSUE

The movements and stability of the human shoulder are a complex dynamic interaction between several joints, muscles and ligaments, which on the one hand enable extensive mobility and on the other hand must provide the necessary stability. Furthermore, the complexity of the shoulder is increased by a large number of normal variants. This article aims to explain the relevant anatomical structures and the radiological examination techniques necessary to visualize them.

STANDARD RADIOLOGICAL PROCEDURES

Various modalities contribute to the examination of the shoulder. These include X‑rays, computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound.

METHODOLOGICAL INNOVATION

It is important to use the various procedures appropriately. Especially with MRI arthrography, it is necessary to pay attention to suitable sequences and possibly additional examination positions.

PRACTICAL RECOMMENDATION

The multimodal examination of the shoulder can contribute to the diagnosis of numerous clinical pictures. Anatomical and methodological foundations are essential for this.

A step closer to continuous buffer preparation from solids: Predicting powder compaction and how to prevent it

The preparation of buffer solutions used in the biopharmaceutical industry is typically performed manually by the addition of one or multiple buffering reagents to water. Recently, the adaptation of powder feeders for continuous solid feeding was demonstrated for continuous buffer preparation. However, the intrinsic characteristics of powders can change the stability of the process, due to the hygroscopic nature of some substances and humidity induced caking and compaction behavior, but there is no simple and easy methodology available predicting this behavior for buffer species. To predict which buffering reagents are suitable without special precautions and investigate their behavior, force displacement measurements were conducted with a customized rheometer over 18hours. While most of the eight investigated buffering reagents indicated uniform compaction, especially sodium acetate and dipotassium hydrogen phosphate (K₂HPO₄) showed a significant increase in yield stress after 2hours. Experiments conducted with a 3D printed miniaturized screw conveyor confirmed the increased yield stress measurement by visible compaction and failure of the feeding. By taking additional precautions and adjusting the design of the hopper, we demonstrated a highly linear profile of all buffering reagents over a duration of 12 and 24hours. We showed that force displacement measurements accurately predict the behavior of buffer components in continuous feeding devices for continuous buffer preparation and are a valuable tool to identify buffer components that need special precautions. Stable, precise feeding of all tested buffer components was demonstrated, showing the importance of identifying buffers that need a specialized setup with a fast methodology.

[Sports-related injuries of the thumb and fingers]

Finger and thumb injuries are common in established and trend sports. Imaging plays an important role in acute trauma care, further therapy planning, and ultimately for a rapid return to play. Sound knowledge of the complex anatomy of the fingers and thumb is indispensable for accurate diagnosis. This article presents the ligament anatomy of the metacarpophalangeal and interphalangeal joints of the finger and the thumb, the extensor and flexor tendon apparatus, and the diagnosis of typical sports injuries using x‑rays and magnetic resonance imaging. Furthermore, imaging findings of typical sports-associated injuries are illustrated.

[Developmental neurology - networked medicine and new perspectives]

Developmental neurology is one of the major areas of neuropediatrics and is among other things (legally) responsible for monitoring the motor, cognitive and psychosocial development of all infants using standardized monitoring investigations. The special focus is on infants born at risk and/or due to premature birth before 32 weeks of gestation or a birth weight less than 1500 g. Early diagnosis of deviations from normal, age-related development is a prerequisite for early interventions, which may positively influence development and the long-term biopsychosocial prognosis of the patients. This article illustrates the available methods in developmental neurology with a focus on recent developments. Particular attention is paid to the predictive value of general movements (GM). The current development of markerless automated detection of spontaneous movements using conventional depth imaging cameras is demonstrated. Differences in spontaneous movements in infants at the age of 12 weeks are illustrated and discussed exemplified by three patients (healthy versus genetic syndrome versus cerebral palsy).