Search

BACKGROUND: Pulmonary hemorrhage (PH) is occasionally seen in premature infants after surfactant treatment for respiratory distress syndrome (RDS). These infants receive frequent chest radiographs (CXR) during and after hospitalization enabling long-term radiographic-clinical correlation. OBJECTIVE: To chart the natural evolution of CXR findings of PH in RDS and correlate radiographic patterns to supplemental oxygen requirement. MATERIALS AND METHODS: Retrospective review of clinical notes for gestational age (GA), birth weight (BW), intraventricular hemorrhage (IVH) and oxygen requirement were performed. CXRs were reviewed at 4 time-points; during PH, 28 days postnatal age, 36 weeks and at farthest available clinical follow-up. RESULTS: 18 infants born (2003–2016), GA (24–30 weeks); BW (482–1590 grams) were included. Mean onset of PH was 1.94 (0–5) days. 9/18 (50%) had IVH. 3 died during PH; all had IVH. During PH, CXR showed whiteout 9/18 (50%); patchy opacities 5/18 (27%); diffuse haziness 1/18 (6%) and no change 3/18 (17%). At 28 days postnatal age, CXR showed fine-interstitial (FI) markings 14/15 (93%) and whiteout 1/15 (7%). At 36 weeks,12/14 (85%) had FI and 2/14 (15%) developed cystic-interstitial changes. At farthest follow-up, FI 3/13 (23%); coarse-interstitial 4/13 (30%); peri-bronchial cuffing 5/13 (38%); normal 1/13 (9%) and the majority had hyperinflation 9/13 (69%). At discharge, 9/14 (64%) required home-oxygen and 5/14 (36%) were on room-air. At farthest follow-up, 6/14 (42%) required home-oxygen and 8/14 (58%) were on room-air. CONCLUSION: Premature infants that survive PH may later develop chronic lung disease of prematurity with an evolving interstitial pattern on CXR that clears overtime as they outgrow the need for supplemental oxygen. [ABSTRACT FROM AUTHOR]

The sensory epithelium within the mammalian cochlea (the organ of Corti) is a strictly ordered cellular array consisting of sensory hair cells and nonsensory supporting cells. Previous research has demonstrated that Notch-mediated lateral inhibition plays a key role in the determination of cell types within this array. Specificallly, genetic deletion of the Notch ligand, Jagged2, results in a significant increase in the number of hair cells that develop within the sensory epithelium, presumably as a result of a decrease in Notch activation. In contrast, the downstream mediators and targets of the Notch pathway in the inner ear have not been determined but they may include genes encoding the proneural gene Math1 as well as the HES family of inhibitory bHLH proteins. To determine the potential roles of these genes in cochlear development, in situ hybridization for Math1 and HES5 was performed on the cochleae of wild-type vs. Jagged2 mutants (Jag2deltaDSL). Results in wild-type cochleae show that expression of Math1 transcripts in the duct begins on E13 and ultimately becomes restricted to hair cells in the sensory epithelium. In contrast, expression of HES5 begins on E15 and becomes restricted to supporting cells in the epithelium. Results in Jag2 mutant cochleae suggest that Math1 transcripts are ultimately maintained in a larger number of cells as compared with wild-type, while transcripts for HES5 are dramatically reduced throughout the epithelium. These results are consistent with the hypothesis that activation of Notch via Jagged2 acts to inhibit expression of Math1 in cochlear progenitor cells, possibly through the activity of HES5. [ABSTRACT FROM AUTHOR]

Aim: To evaluate dual-source high-pitch computed tomography (HPCT) imaging of the chest and abdomen as a rapid scanning technique to obtain diagnostic-quality imaging evaluation of infants and young children without sedation.Materials and Methods: Fifty-three paediatric patients (age 24.1±2 months) who underwent chest or abdomen HPCT (≥1.5) and standard pitch CT (SPCT, <1.5) on a dual-source 128-row multidetector CT system were included in the study. Image quality assessment was performed by two paediatric radiologists for diagnostic confidence, image artefacts, and image noise. Objective image noise was measured.Results: Most of the CT examinations were performed in children who were >1 year old (n=15 and n=20) followed by ≤1 year old (n=8 and n=10) in SPCT and HPCT, respectively. The mean radiation dose (SSDE) from HPCT was 1.96±1 mGy compared to 2.2±1 mGy for SPCT (p=0.3). No major artefacts were reported and overall image quality of all HPCT examinations was acceptable diagnostically. In addition, objective image noise values were not significantly different between HPCT compared with SPCT (11±3 versus 11±5, p=0.7).Conclusion: Ultra-fast, HPCT can be performed without the need for sedation as a potential alternative to anaesthetised magnetic resonance imaging in infants and young children. [ABSTRACT FROM AUTHOR]