The quantitative parameters derived from IDEAL-IQ in the lumbar vertebrae of healthy children: a pilot study of bone development.

Background: Early childhood bone development affects that of bone disease in adolescence and adulthood. Many diseases can affect the cancellous bone or bone marrow. Therefore, it is of great significance to quantify the bone development of healthy children. The evaluation methods of bone development include bone age (BA) assessment and dual-energy X-ray bone mineral densitometry (DXA), both of which have strong subjectivity. The present study was conducted to improve our understanding of the bone development of healthy children using the quantitative parameters derived from iterative decomposition of water and fat with echo asymmetry and least squares estimation quantification (IDEAL-IQ) sequence. Methods: Our study enrolled healthy children between January 2022 to December 2022 consecutively in Children's Hospital of Shanxi. The inclusion criteria were as follows: (I) age ≤18 years; (II) no contraindications (surgical and interventional devices for ferromagnetic materials, cardiac implantable electronic devices, cochlear implants, insulin pumps, dental implants containing metal or alloy) to magnetic resonance imaging (MRI) scan. The exclusion criteria were as follows: (I) previous malignant disease, (II) previous chemoradiotherapy, (III) previous spine surgery, (IV) previous or acute vertebral compression fracture, (V) artifacts present in images. Participants underwent MRI scans using IDEAL-IQ sequence in the lumbar vertebrae. The IDEAL-IQ parameters [proton density fat fraction (PDFF), 1/T2* (R2*)] were obtained. The factor analysis of variance was applied to compare the differences of PDFF and R2* in different lumbar vertebral groups. The Kruskal-Wallis H test or Mann-Whitney U test was applied to compare the differences of quantitative data among different gender or age groups. Spearman correlation analysis was applied to study the relationship among the age, PDFF, and R2*. Results: A total of 145 participants (76 males, 69 females) were evaluated. There were no significant differences in PDFF and R2* of different lumbar vertebrae (PPDFF=0.338, PR2*=0.868). The average age was 36 [13-72] months. They were assigned into 4 groups (0-11, 12-35, 36-71, and 72-144 months). As the age increased, the average PDFF and R2* both increased significantly (rPDFF=0.659, rR2*=0.359, P<0.001). There were significant statistical differences in PDFF and R2* between the 4 age groups (ZPDFF=46.651, ZR2*=27.537, P<0.001). Moreover, the PDFF was also positively correlated with R2* (r=0.576, P<0.001). No association was found between the gender and PDFF, R2* (PPDFF=0.949, PR2*=0.177). Conclusions: The quantitative parameters derived from IDEAL-IQ in the lumbar vertebrae of healthy children will improve our understanding of bone development and provide a basis for further exploring the diseases that affect children's bone development.

A Pilot Study of Prognostic Value of Metastatic Lymph Node Count and Size in Patients with Different Stages of Gastric Carcinoma.

Background: The correlation between the preoperative lymph node count (LNC) on multidetector computed tomography (MDCT) and the prognosis of gastric carcinoma (GC) remains to be defined. This research aims to evaluate the prognostic value of LNC on MDCT in GC patients based on tumor-node-metastasis (TNM) staging, using different size criteria for counting. Methods: The clinical data of 126 patients with gastric adenocarcinoma undergoing gastrectomy were retrospectively analyzed. Lymph nodes greater than 8mm and 5mm on MDCT were counted and recorded. The prognostic implications of LNC on MDCT for patient survival were analyzed according to different size criteria for counting and tumor TNM staging. Results: When 8mm was used as the counting criterion, LNC on MDCT had no significant effect on the overall survival (OS) of the entire cohort. In addition, the OS of T1-T2 GC patients with LNC on MDCT ≥1 was significantly worse than that of patients with LNC on MDCT <1. When 5mm was used as the counting criterion, LNC on MDCT was found to be significantly associated with the OS of the entire cohort. In the subgroup analysis, patients with relatively advanced (T3-T4, N+ and III) GC with LNC on MDCT >7 showed a significantly worse OS than those with LNC on MDCT ≤7. LNC on MDCT >7 with 5mm as the counting criterion and Stage III were independent risk factors for adverse prognosis. Conclusion: The prognostic value of LNC on MDCT based on different size criteria varies in patients with different stages of GC. LNC of a smaller size (5mm) on MDCT may be a prognostic factor for patients with relatively advanced GC.

Altered white matter microstructure in patients with post-stroke depression detected by diffusion kurtosis imaging.

The aim of our study is to determine the pathological changes of white matter microstructure in patients with early post-stroke depression (PSD), and to investigate the association between white matter integrity examined by diffusion kurtosis imaging (DKI) and early PSD. Thirty-eight patients with acute cerebral infarction were selected, including 17 patients with depression (PSD group), and 21 patients without depression (N-PSD group). In addition, 20 normal healthy controls (NORM group) were selected. All were taken DKI scans. The white matter of the frontal lobe, temporal lobe, parietal lobe, occipital lobe, anterior limb of internal capsule, and posterior limb of internal capsule, in addition to the genu of corpus callosum and splenium of corpus callosum was selected as a region of interest (ROI). Selected parameters include fractional anisotropy (FA) and mean kurtosis (MK). Compared with N-PSD group and NORM group, FA value of the left frontal lobe and MK value of the bilateral frontal lobe, bilateral temporal lobe, and genu of corpus callosum in PSD group were decreased (P < 0.05). Our results indicated that the early PSD patients had white matter microstructure abnormalities in the frontal lobe, temporal lobe, and genu of corpus callosum. DKI provides a comprehensive brain imaging reference for detecting early microstructural damage of white matter in PSD patients, which can be used as an imaging biomarker to detect early PSD and its progression potentially.

[Comparison of the two magnetic resonance deartifact techniques in imaging of different porcelain-fused-to-metal crowns].

OBJECTIVE: This study aimed to compare the porcelain-fused-to-metal (PFM) crown artifact in the magnetic resonance imaging (MRI) of the two magnetic resonance deartifact techniques in studying the application value of the propeller-fast spin-echo T2-weighted sequence (FSE T2WI) in troubleshooting PFM crown artifacts. METHODS: A total of 48 patients with right mandible first molar crown who underwent MRI head examination were chosen as subjects in the study. According to different metal substrates, PFM crowns were divided to three types, namely, nickel-chromium alloy crown, cobalt-chromium alloy crown and titanium crown. The patients received two MRI scan sequences, that is, FSE T2WI and propeller-FSE T2WI sequences. The MRI artifacts areas in two sequences were measured. RESULTS: The difference between FSE T2WI and propeller-FSE T2WI sequences in three kinds of PFM crown was significant (P<0.05). CONCLUSIONS: Propeller-FSE T2WI sequence technique can effectively reduce the metal artifacts of various PFM crowns.