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BACKGROUND. Hippocampal sclerosis (HS) is a leading cause of medically refractory temporal lobe epilepsy in children. The diagnosis is clinically important because most patients with HS have good p...

OBJECTIVE. The aim of this study was to develop a low-dose radiography protocol for the neonatal ICU (NICU) using a new mobile digital radiography system with advanced denoising image processing and to evaluate the noninferiority of that protocol. SUBJECTS AND METHODS. In this prospective randomized study, 40 neonates in the NICU underwent radiography of the thorax and abdomen with two different mobile radiography units: conventional technique on one unit (50 kV, 1.6 mAs, and no additional filtration) and a new technique on another unit (54 kV, 0.1-mm Cu filtration). Three low-dose protocols for the second unit were developed in a phantom study: protocol A (100% equivalent dose with conventional protocol), protocol B (80% equivalent dose), and protocol C (64% equivalent dose). The noninferiority of each low-dose protocol was assessed by three independent readers using image quality criteria. RESULTS. Forty patients each underwent three pairs of radiography examinations (protocol A and the conventional protocol, protocol B and the conventional protocol, and protocol C and the conventional protocol), except one pair that did not include one image of the conventional protocol. The interrater reliability among the three readers was 0.91 (p < 0.001). Both of the low-dose protocols (B and C) were statistically noninferior to the conventional protocol with respect to overall image quality. Protocol B better depicted almost all anatomic landmarks and had better overall image quality than the conventional protocol. CONCLUSION. Using appropriate technique and acquisition factors, radiation dose can be lowered on a digital radiography system without significant effect on the image quality by adding filtrations and a new denoising technique.

The purpose of this study is to compare DWI for pediatric brain evaluation using single-shot echo-planar imaging (EPI), periodically rotated overlapping parallel lines with enhanced reconstruction (Blade), and readout-segmented EPI (Resolve).Blade, Resolve, and single-shot EPI were performed for 27 pediatric patients (median age, 9 years), and three datasets were independently reviewed by two radiologists. Qualitative analyses were performed for perceptive coarseness, image distortion, susceptibility-related changes, motion artifacts, and lesion conspicuity using a 5-point Likert scale. Quantitative analyses were conducted for spatial distortion and signal uniformity of each sequence.Mean scores were 2.13, 3.17, and 3.76 for perceptive coarseness; 4.85, 3.96, and 2.19 for image distortion; 4.76, 3.96, and 2.30 for susceptibility-related change; 4.96, 3.83, and 4.69 for motion artifacts; and 2.71, 3.75, and 1.92 for lesion conspicuity, for Blade, Resolve, and single-shot EPI, respectively. Blade and Resolve showed better quality than did single-shot EPI for image distortion, susceptibility-related changes, and lesion conspicuity. Blade showed less image distortion, fewer susceptibility-related changes, and fewer motion artifacts than did Resolve, whereas lesion conspicuity was better with Resolve. Blade showed increased signal variation compared with Resolve and single-shot EPI (coefficients of variation were 0.10, 0.08, and 0.05 for lateral ventricle; 0.13, 0.09, and 0.05 for centrum semiovale; and 0.16, 0.09, and 0.06 for pons in Blade, Resolve, and single-shot EPI, respectively).DWI with Resolve or Blade yields better quality regarding distortion, susceptibility-related changes, and lesion conspicuity, compared with single-shot EPI. Blade is less susceptible to motion artifacts than is Resolve, whereas Resolve yields less noise and better lesion conspicuity than does Blade.

The purpose of this study was to evaluate the usefulness of radially sampled 3D fat-suppressed T1-weighted gradient-echo sequences (radial volumetric interpolated breath-hold examination [radial VIBE]) for contrast-enhanced brain MRI of children through comparison with a magnetization-prepared rapid-acquisition gradient-echo (MP-RAGE) sequence.Sixty-five consecutive contrast-enhanced brain MRI examinations performed with axial MP-RAGE and radial VIBE sequences were included. For quantitative analysis, coefficients of variation of gray matter and white matter and CSF and relative contrast between tissue types (gray matter and white matter, gray matter and CSF, and white matter and CSF) for each sequence were calculated. For qualitative assessment, motion, pulsation artifacts, overall image quality, and lesion conspicuity were retrospectively scored on a 5-point scale. Quantitative and qualitative subgroup analyses were performed for patients with serious motion artifacts.Images obtained with the radial VIBE sequence had fewer motion and pulsation artifacts than those obtained with the MP-RAGE sequence (MP-RAGE vs radial VIBE motion score, 3.57 ± 1.00 vs 4.52 ± 0.51; pulsation score, 3.57 ± 0.60 vs 4.91 ± 0.21; all p0.001). Among 25 images with serious motion artifacts, radial VIBE images had significantly higher scores for all qualitative parameters, including overall image quality, than did MP-RAGE images (overall image quality for MP-RAGE vs radial VIBE, 2.63 ± 0.82 vs 3.42 ± 0.55, p0.001).The study showed that a radial fat-suppressed T1-weighted gradient-echo sequence is a viable alternative to conventional cartesian acquisition for contrast-enhanced brain imaging of restless children.

The purpose of this study was to compare free-breathing radially sampled 3D T1-weighted gradient-echo acquisitions (radial volumetric interpolated breath-hold examination [VIBE]) with a T1-weighted turbo spin-echo (TSE) sequence for contrast-enhanced spinal imaging of children with CNS tumors.Twenty-eight consecutively registered children with CNS tumors underwent evaluation of leptomeningeal seeding with 1.5-T MRI that included both radial VIBE and T1-weighted TSE sequences. For qualitative analysis, overall image quality; presence of motion, CSF flow, and radial artifacts; and lesion conspicuity were retrospectively assessed with scoring systems. The signal-intensity uniformity of each sequence was evaluated for quantitative comparison. The acquisition times for each sequence were compared.Images obtained with the radial VIBE sequence had a higher overall image quality score than did T1-weighted TSE images (3.61 ± 0.73 vs 2.80 ± 0.69, p0.001) and lower motion artifact (0.82 ± 0.43 vs 1.29 ± 0.56, p = 0.001) and CSF flow artifact (0 vs 1.68 ± 0.67, p0.001) scores. Radial artifacts were found only on radial VIBE images (1.36 ± 0.31 vs 0, p0.001). In 13 patients with spinal seeding nodules, radial VIBE images showed greater lesion conspicuity than did T1-weighted TSE images (4.23 ± 0.52 vs 2.47 ± 0.57, p = 0.005). Radial VIBE images had diminished signal-intensity variation compared with T1-weighted TSE images in air, spine, and muscle (p0.01). The mean acquisition times were not significantly different between the two sequences (p = 0.117).For pediatric spinal imaging, radial VIBE images had better image quality and lesion conspicuity and fewer CSF and respiratory motion artifacts than did T1-weighted TSE images in a similar acquisition time.

OBJECTIVE. The purpose of this study was to evaluate retrospectively the CT and sonographic features in nine children with pathologically proven inflammatory myofibroblastic tumors of the abdomen.CONCLUSION. Although inflammatory myofibroblastic tumors occur in various sites and the imaging characteristics are variable, tumors showed different imaging patterns that were dependent on the site at which the tumor had originated.

The purpose of our study was to determine whether CT provides additional information for children with a suspected residual foreign body in the airway after bronchoscopy.We reviewed the CT findings and medical records of nine patients (five girls and four boys; mean age, 17.9 months) who underwent CT between March 1999 and February 2007 for the evaluation of a clinically suspected residual foreign body in the airway after bronchoscopy. We evaluated the location and pattern of bronchial obstruction and associated parenchymal abnormalities on CT. CT findings were compared with a second bronchoscopy in five patients. The remaining four patients were followed clinically. Association between CT findings and results on second bronchoscopy was evaluated with Fisher's exact test.CT after bronchoscopy (n = 9) showed bronchial obstruction in eight patients with focal complete (n = 3), diffuse (n = 3), or combined type (n = 2) bronchial obstruction. These obstructions were not seen at chest radiography. CT revealed unilateral or lobar emphysema (n = 6), atelectasis (n = 6), and consolidation (n = 1). The remaining one patient showed no abnormality on CT. A second bronchoscopy (n = 5) confirmed the focal complete bronchial obstruction at CT (n = 3) as retained foreign body fragments (n = 2) or mucus plug (n = 1) and the combined type at CT (n = 2) as retained foreign body fragments, granulation tissue, and edema of the bronchus (n = 1) or retained foreign body fragments, granulation tissue, and mucus plug (n = 1). There was a significant association between CT findings of type of bronchial obstruction and intrabronchial obstructive lesion on the second bronchoscopy (p = 0.036).CT after bronchoscopy can provide additional information regarding the presence and pattern of bronchial obstruction in children with a suspected residual foreign body.

OBJECTIVE: Our objective was to assess the radiographic and CT findings of acute eosinophilic pneumonia. CONCLUSION: Initial and follow-up chest radiographs, chest CT scans (n = 5) and clinical data in six patients with acute eosinophilic pneumonia were reviewed by two chest radiologists. The predominant initial radiographic finding was diffuse bilateral reticular densities (four [67%] of six patients). Areas of ground-glass opacity were observed on CT scans in all patients (5 of 5) and were bilateral, random, and patchy in distribution in four (80%) of five patients. Smooth septal thickening and pleural effusions were observed in four patients. The disease manifested as rapid onset of severe dyspnea and fever and rapid resolution with (n = 3) or without (n = 3) steroid therapy. Bilateral reticular densities on chest radiographs and, on CT scans, ground-glass opacity with smooth septal thickening and pleural effusion associated with acute fever and dyspnea may suggest the diagnosis of acute eosinophilic p...