Diagnostic performance of synthetic relaxometry for predicting neurodevelopmental outcomes in premature infants: a feasibility study.

OBJECTIVES: To investigate the predictability of synthetic relaxometry for neurodevelopmental outcomes in premature infants and to evaluate whether a combination of relaxation times with clinical variables or qualitative MRI abnormalities improves the predictive performance. METHODS: This retrospective study included 33 premature infants scanned with synthetic MRI near or at term equivalent age. Based on neurodevelopmental assessments at 18-24 months of corrected age, infants were classified into two groups (no/mild disability [n = 23] vs. moderate/severe disability [n = 10]). Clinical and MRI characteristics associated with moderate/severe disability were explored, and combined models incorporating independent predictors were established. Ultimately, the predictability of relaxation times, clinical variables, MRI findings, and a combination of the two were evaluated and compared. The models were internally validated using bootstrap resampling. RESULTS: Prolonged T1-frontal/parietal and T2-parietal periventricular white matter (PVWM), moderate-to-severe white matter abnormality, and bronchopulmonary dysplasia were significantly associated with moderate/severe disability. The overall predictive performance of each T1-frontal/-parietal PVWM model was comparable to that of individual MRI finding and clinical models (AUC = 0.71 and 0.76 vs. 0.73 vs. 0.83, respectively; p > 0.27). The combination of clinical variables and T1-parietal PVWM achieved an AUC of 0.94, sensitivity of 90%, and specificity of 91.3%, outperforming the clinical model alone (p = 0.049). The combination of MRI finding and T1-frontal PVWM yielded AUC of 0.86, marginally outperforming the MRI finding model (p = 0.09). Bootstrap resampling showed that the models were valid. CONCLUSIONS: It is feasible to predict adverse outcomes in premature infants by using early synthetic relaxometry. Combining relaxation time with clinical variables or MRI finding improved prediction. CLINICAL RELEVANCE STATEMENT: Synthetic relaxometry performed during the neonatal period may serve as a biomarker for predicting adverse neurodevelopmental outcomes in premature infants. KEY POINTS: • Synthetic relaxometry based on T1 relaxation time of parietal periventricular white matter showed acceptable performance in predicting adverse outcome with an AUC of 0.76 and an accuracy of 78.8%. • The combination of relaxation time with clinical variables and/or structural MRI abnormalities improved predictive performance of adverse outcomes. • Synthetic relaxometry performed during the neonatal period helps predict adverse neurodevelopmental outcome in premature infants.

Prenatal Diagnosis of Fetal Obstructed Hemivagina and Ipsilateral Renal Agenesis (OHVIRA) Syndrome.

Background: Obstructed hemivagina and ipsilateral renal agenesis (OHVIRA) syndrome, also known as Herlyn-Werner-Wunderlich syndrome, is a rare syndrome characterized by the triad of uterus didelphys, obstructed hemivagina, and ipsilateral renal agenesis. Most cases of OHVIRA have been reported in adolescents or adults. Gartner duct cysts, including those manifesting as vaginal wall cysts, are also rare. Fetal OHVIRA syndrome and Gartner duct cysts are difficult to diagnose. Case Presentation: Here, the authors report a case of combined OHVIRA and Gartner duct cyst diagnosed prenatally by ultrasonography, along with a brief review of the relevant published reports. A 30-year-old nulliparous female was referred to our institution at 32 weeks' gestation for fetal right kidney agenesis. Detailed ultrasonographic examinations using 2D, 3D, and Doppler ultrasounds revealed hydrocolpometra, and uterus didelphys, with a normal anus and right kidney agenesis. Conclusions: When encountering female fetuses with ipsilateral renal agenesis or vaginal cysts, clinicians should be aware of OHVIRA syndrome and Gartner duct cysts and perform systematic ultrasonographic examinations for other genitourinary anomalies.

Adaptation of Deep Learning Image Reconstruction for Pediatric Head CT: A Focus on the Image Quality.

Purpose: To assess the effect of deep learning image reconstruction (DLIR) for head CT in pediatric patients. Materials and Methods: We collected 126 pediatric head CT images, which were reconstructed using filtered back projection, iterative reconstruction using adaptive statistical iterative reconstruction (ASiR)-V, and all three levels of DLIR (TrueFidelity; GE Healthcare). Each image set group was divided into four subgroups according to the patients' ages. Clinical and dose-related data were reviewed. Quantitative parameters, including the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR), and qualitative parameters, including noise, gray matter-white matter (GM-WM) differentiation, sharpness, artifact, acceptability, and unfamiliar texture change were evaluated and compared. Results: The SNR and CNR of each level in each age group increased among strength levels of DLIR. High-level DLIR showed a significantly improved SNR and CNR (p < 0.05). Sequential reduction of noise, improvement of GM-WM differentiation, and improvement of sharpness was noted among strength levels of DLIR. Those of high-level DLIR showed a similar value as that with ASiR-V. Artifact and acceptability did not show a significant difference among the adapted levels of DLIR. Conclusion: Adaptation of high-level DLIR for the pediatric head CT can significantly reduce image noise. Modification is needed while processing artifacts.

Prevalence of Incidentally Detected Spondylolysis in Children.

Purpose: To assess the prevalence of incidentally detected lumbar spondylolysis in children. Materials and Methods: We retrospectively reviewed the data of 809 patients under the age of 11 years (mean age, 7.0 ± 2.7 years; boys:girls = 479:330) who underwent abdominal and pelvic CT between March 2014 and December 2018. We recorded the presence, level, and laterality (unilateral or bilateral) of spondylolysis. Patients were divided into two groups based on the presence of spondylolysis: the spondylolysis (SP) and non-SP groups. Results: In total, 21 cases of spondylolysis were detected in 20 patients (20/809, 2.5%). The mean age of the SP group was higher than that of the non-SP group (7.8 ± 1.8 vs. 6.9 ± 2.7 years, p > 0.05). The prevalence of spondylolysis in boys was higher than that in girls (15/479 [3.1%] vs. 5/330 [1.5%], p > 0.05). The prevalence of spondylolysis in school-age children (6-10 year olds) was higher than that in preschool-age children (0-5 year olds) (17/538 [3.2%] vs. 3/271 [1.1%], p > 0.05). L5 was the most common level of spondylolysis (76.2%); one 8-year-old boy had twolevel spondylolysis. One case of isthmic spondylolisthesis was detected in a 10-year-old boy (1/809, 0.1%). There were 11 unilateral spondylolysis cases (11/21, 52.4%). Conclusion: In our study, the prevalence of spondylolysis in children under the age of 11 was 2.5%. The prevalence was higher in boys than in girls and in school-age than in preschool-age children, despite the lack of any statistically significant differences.

Extramedullary Relapse of Acute Lymphoblastic Leukemia Involving the Parotid Gland: A Case Report and Literature Review.

While extramedullary relapse of leukemia could occur, the parotid gland is a rare site of recurrence. Extramedullary relapse involving the parotid gland could be mistaken for other diseases. Moreover, the diagnosis of this disease is often delayed due to its rarity. Herein, we present a case of extramedullary relapse of acute lymphoblastic leukemia involving the parotid gland.

Feasibility of Pediatric Low-Dose Facial CT Reconstructed with Filtered Back Projection Using Adequate Kernels.

Purpose: To evaluate the feasibility of pediatric low-dose facial CT reconstructed with filtered back projection (FBP) using adequate kernels. Materials and Methods: We retrospectively reviewed the clinical and imaging data of children aged < 10 years who underwent facial CT at our emergency department. The patients were divided into two groups: low-dose CT (LDCT; Group A, n = 73) with a fixed 80-kVp tube potential and automatic tube current modulation (ATCM) and standard-dose CT (SDCT; Group B, n = 40) with a fixed 120-kVp tube potential and ATCM. All images were reconstructed with FBP using bone and soft tissue kernels in Group A and only bone kernel in Group B. The groups were compared in terms of image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). Two radiologists subjectively scored the overall image quality of bony and soft tissue structures. The CT dose index volume and dose-length product were recorded. Results: Image noise was higher in Group A than in Group B in bone kernel images (p < 0.001). Group A using a soft tissue kernel showed the highest SNR and CNR for all soft tissue structures (all p < 0.001). In the qualitative analysis of bony structures, Group A scores were found to be similar to or higher than Group B scores on comparing bone kernel images. In the qualitative analysis of soft tissue structures, there was no significant difference between Group A using a soft tissue kernel and Group B using a bone kernel with a soft tissue window setting (p > 0.05). Group A showed a 76.9% reduction in radiation dose compared to Group B (3.2 ± 0.2 mGy vs. 13.9 ± 1.5 mGy; p < 0.001). Conclusion: The addition of a soft tissue kernel image to conventional CT reconstructed with FBP enables the use of pediatric low-dose facial CT protocol while maintaining image quality.

Intestinal Ganglioneuromatosis in a Pediatric Patient Presenting as Perforation: A Case Report and Literature Review.

Intestinal ganglioneuromatosis is an extremely rare condition, particularly in pediatric patients, and the imaging features of the disease have been rarely reported before. Herein, we present a pediatric case of intestinal ganglioneuromatosis involving the transverse colon and splenic flexure with bowel perforation, which is a rare initial manifestation of the disease.

Left ventricular rehabilitation in an infant with transposition of the great arteries, intact ventricular septum, pulmonary stenosis and small left ventricle.

We report the case of successful biventricular repair after left ventricular rehabilitation in an infant with transposition of the great arteries with an intact ventricular septum, pulmonary stenosis, a large atrial septal defect and a borderline small left ventricle (mitral annulus z-score: -3.6). This baby presented to us at 2 months of age after having a modified Blalock-Taussig shunt at another hospital. We restricted the atrial septal defect with the child on cardiopulmonary bypass. Ten weeks later, the mitral annulus z-score increased to -1.5, and the transpulmonary peak pressure gradient increased to 87 mmHg. Subsequently, we performed the aortic root translocation. The patient is currently an active 4-year-old boy.

Time-saving synthetic magnetic resonance imaging protocols for pediatric neuroimaging: impact of echo train length and bandwidth on image quality.

BACKGROUND: Synthetic MRI is a time-efficient imaging technique that provides both quantitative MRI and contrast-weighted images simultaneously. However, a rather long single scan time can be challenging for children. OBJECTIVE: To evaluate the clinical feasibility of time-saving synthetic MRI protocols adjusted for echo train length and receiver bandwidth in pediatric neuroimaging based on image quality assessment and quantitative data analysis. MATERIALS AND METHODS: In total, we included 33 children ages 1.6-17.4 years who underwent synthetic MRI using three sets of echo train length and receiver bandwidth combinations (echo train length [E]12-bandwidth [B in KHz]22, E16-B22 and E16-B83) at 3 T. The image quality and lesion conspicuity of synthetic contrast-weighted images were compared between the suggested protocol (E12-B22) and adjusted protocols (E16-B22 and E16-B83). We also compared tissue values (T1, T2, proton-density values) and brain volumetry. RESULTS: For the E16-B83 combination, image quality was sufficient except for 15.2% of T1-W and 3% of T2-W fluid-attenuated inversion recovery (FLAIR) images, with remarkable scan time reduction (up to 35%). The E16-B22 combination demonstrated a comparable image quality to E12-B22 (P>0.05) with a scan time reduction of up to 8%. There were no significant differences in lesion conspicuity among the three protocols (P>0.05). Tissue value measurements and brain tissue volumes obtained with the E12-B22 protocol and adjusted protocols showed excellent agreement and strong correlations except for gray matter volume and non-white matter/gray matter/cerebrospinal fluid volume in E12-B22 vs. E16-B83. CONCLUSION: The adjusted synthetic protocols produced image quality sufficient or comparable to that of the suggested protocol while maintaining lesion conspicuity with reduced scan time. The quantitative values were generally consistent with the suggested MRI-protocol-derived values, which supports the clinical application of adjusted protocols in pediatric neuroimaging.

Clinical adaptation of synthetic MRI-based whole brain volume segmentation in children at 3 T: comparison with modified SPM segmentation methods.

PURPOSE: To validate the use of synthetic magnetic resonance imaging (SyMRI) volumetry by comparing with child-optimized SPM 12 volumetry in 3 T pediatric neuroimaging. METHODS: In total, 106 children aged 4.7-18.7 years who underwent both synthetic and 3D T1-weighted imaging and had no abnormal imaging/neurologic findings were included for the SyMRI vs. SPM T1-only segmentation (SPM T1). Forty of the 106 children who underwent an additional 3D T2-weighted imaging were included for the SyMRI vs. SPM multispectral segmentation (SPM multi). SPM segmentation using an age-appropriate atlas and inverse-transforming template-space intracranial mask was compared with SyMRI segmentation. Volume differences between SyMRI and SPM T1 were plotted against age to evaluate the influence of age on volume difference. RESULTS: Measurements derived from SyMRI and two SPM methods showed excellent agreements and strong correlations except for the CSF volume (CSFV) (intraclass correlation coefficients = 0.87-0.98; r = 0.78-0.96; relative volume difference other than CSFV = 6.8-18.5% [SyMRI vs. SPM T1] and 11.3-22.7% [SyMRI vs. SPM multi]). Dice coefficients of all brain tissues (except CSF) were in the range 0.78-0.91. The Bland-Altman plot and age-related volume difference change suggested that the volume differences between the two methods were influenced by the volume of each brain tissue and subject's age (p < 0.05). CONCLUSION: SyMRI and SPM segmentation results were consistent except for CSFV, which supports routine clinical use of SyMRI-based volumetry in pediatric neuroimaging. However, caution should be taken in the interpretation of the CSF segmentation results.

Bowel Wall Thickening on Computed Tomography in Children: A Novel Method of Measurement and Its Clinical Significance.

PURPOSE: The clinical implications of bowel wall thickening (BWT) on abdominal computed tomography (CT) among children are unknown. We aimed to suggest a new method for measuring BWT and determining its clinical significance in children. METHODS: We retrospectively analyzed 423 patients with acute abdomen who underwent abdominal CT; 262 were classified into the BWT group. For this group, the pediatric radiologist described the maximal bowel wall thickness (MT), normal bowel wall thickness (mm) (NT), and their ratios for each segment of the bowel wall. RESULTS: In the thickened bowel walls, the thickness differed significantly between the small bowel (6.83±2.14 mm; mean±standard deviation) and the colon (8.56±3.46 mm; p<0.001). The ratios of MT to NT in the small bowel (6.09±3.17) and the colon (7.58±3.70) were also significantly different (p<0.001). In the BWT group, 35 of 53 patients had positive fecal polymerase chain reaction results; 6 patients infected with viruses predominantly had BWT in the small intestine, while the terminal ileum and the colon were predominantly affected in 29 patients with bacterial infections. In the initially undiagnosed 158 patients with BWT, the symptoms improved spontaneously without progression to chronic gastrointestinal disease. CONCLUSION: This study provides a clinical reference value for BWT in the small intestine and colon using a new method in children. The BWT on abdominal CT in children might indicate nonspecific findings that can be observed and followed up without additional evaluation, unlike in adults.

Significance of sonographically detected bladder debris in children less than 2 years old with febrile urinary tract infection.

PURPOSE: To investigate the relationship between bladder debris found on renal and bladder ultrasonography (RBUS) and the first febrile urinary tract infection (UTI) episode in children under 2 years old. METHODS: We retrospectively reviewed the data of children aged <2 years with the first febrile UTI. We recorded bladder debris on RBUS and other findings (blood test, urinalysis, and urine culture). Other RBUS findings (renal pelvis debris, renal parenchymal change, wall thickening, and renal collecting system [RCS] dilatation) were recorded. Patients were divided into the debris (D) and non-D groups. RESULTS: Of 128 patients (boys: girls = 81:47, mean age = 5.6 ± 4.2 months), 24 (18.8%) had bladder debris. The mean C-reactive protein (CRP) levels were higher in the D group (6.1 ± 4.0 vs 4.3 ± 3.5, P = .03). Twenty-one patients in the D group (87.5%) had hematuria (odds ratio = 3.706, 95% confidence interval = 1.035-13.267, P = .04). No significant differences were seen in the urine culture results between both groups. Significant associations were seen between bladder debris and other RBUS findings such as debris in renal pelvis, renal parenchymal change, and RCS wall thickening. CONCLUSION: Bladder debris on RBUS is a common finding in children aged <2 years during the first febrile UTI. Bladder debris was related to higher CRP levels, hematuria and sonographic findings, but not to urine culture results.

[Gastrointestinal Emergencies in Neonates: What We Should Know]. / ì‹ ìƒì•„ 위장관 응급 질환: 알아야 í• ì˜ìƒì˜í•™ì  소견.

Newborn gastrointestinal tract emergency diseases include various disorders that occur anywhere along the digestive tract. Most of them are congenital malformations, not acquired diseases. Many of them cannot be confirmed on prenatal examination, and consequently, postnatal evaluation is required. Unlike adults, in newborn babies, detailed evaluations with computed tomography (CT) and magnetic resonance imaging (MRI) are often limited, so making the diagnosis based on early abdominal radiography is most important. Therefore, it is necessary to be familiar with the radiologic findings that may be seen on imaging studies. In addition, it is important to understand abdominal ultrasound and fluoroscopy findings, which can be used in addition to simple radiography and indications that can be used for further diagnosis and appropriate treatment. Therefore, this study describes and organizes the various imaging findings that may occur in neonatal gastrointestinal emergencies.

Detection of Incidental Prostate Cancer or Urothelial Carcinoma Extension in Urinary Bladder Cancer Patients by Using Multiparametric MRI: A Retrospective Study Using Prostate Imaging Reporting and Data System Version 2.0.

Purpose: The study aimed to investigate the role of Prostate Imaging Reporting and Data System version 2 (PI-RADS v2) in predicting incidental prostate cancer (PCa) or urothelial carcinoma (UCa) extension in urinary bladder (UB) cancer patients. Materials and Methods: A total of 72 UB cancer patients who underwent radical cystoprostatectomy and 3 Tesla multiparametric MRI before surgery were enrolled. PI-RADS v2 ratings were assigned by two independent radiologists. All prostate specimens were examined by a single pathologist. We compared the multiparametric MRI findings rated using PI-RADS v2 with the pathologic data. Results: Of the 72 UB cancer patients, 29 had incidental PCa (40.3%) and 20 showed UCa extension (27.8%), with an overlap for 3 patients. With a score of 4 as the cut-off value for predicting incidental PCa, the diagnostic accuracy was 65.3%, specificity was 90.7%, and positive predictive value (PPV) was 66.7%. The diagnostic accuracy for incidental UCa extension was 47.2%, specificity was 92.3%, and PPV was 83.3%. Conclusion: Despite the low diagnostic accuracy, the PPV and specificity were relatively high. Therefore, PI-RADS v2 scores of 1, 2, or 3 may help exclude the probability of incidental PCa or UCa extension.

Pediatric head computed tomography with advanced modeled iterative reconstruction: focus on image quality and reduction of radiation dose.

BACKGROUND: Iterative reconstruction has become the standard method for reconstructing computed tomography (CT) scans and needs to be verified for adaptation. OBJECTIVE: To assess the image quality after adapting advanced modeled iterative reconstruction (ADMIRE) for pediatric head CT. MATERIALS AND METHODS: We included image sets with filtered back projection reconstruction (the cFBP group, n=105) and both filtered back projection and ADMIRE reconstruction (the lower-dose group, n=109) after dose reduction. All five strength levels of ADMIRE and filtered back projection were adapted for the lower-dose group and compared with the cFBP group. Quantitative parameters including noise, signal-to-noise ratio and contrast-to-noise ratio and qualitative parameters including noise, white matter and gray matter differentiation of the supra- and infratentorial levels, sharpness, artifact, and diagnostic accuracy were also evaluated and compared with interobserver agreement. RESULTS: There was a mean dose reduction of 30.6% in CT dose index volume, 32.1% in dose length product, and 32.1% in effective dose after tube current reduction. There was gradual reduction of noise in air, cerebrospinal fluid and white matter with strength levels of ADMIRE from 1 to 5 (P<0.001). Signal-to-noise ratio and contrast-to-noise ratio in all age groups increased among strength levels of ADMIRE, in sequence from 1 to 5, with statistical significance (P<0.001). Gradual reduction of qualitative parameters was noted among strength levels of ADMIRE in sequence from 1 to 5 (P<0.001). CONCLUSION: Use of ADMIRE for pediatric head CT can reduce radiation dose without degrading image quality.

Effect of using immobilization device in fluoroscopic study in pediatric patient: Focused on radiation dose reduction in voiding cystourethrogram.

INTRODUCTION: To prove objective effect of using mechanical device for immobilization of pediatric patient during voiding cystourethrogram (VCUG) compare immobilization by hand-holding. METHODS: This study included 77 patients, who underwent VCUG in our center from April to October 2017, who had a clinically suspicious urinary tract infection. Patients were classified into one of two groups based on whether examination was done before (Group A) or after (Group B) adaptation of immobilization device. Patient-related data, image quality related score and dose-related data were collected and compared between two groups. RESULTS: Group A included 36 patients and group B included 41. Patient related data including mean age, sex, body weight and height didn't show significant difference between two groups (p > 0.05 for all). Among the image quality scoring, overall image quality, motion artifact, showed significant difference between two groups with improved inadequate timing and centering after adaptation of immobilization device. Dose related data showed significantly decreased shot number, mean fluoroscopic time with decreased mean dose area product (DAP) value and effective dose after adaptation of immobilization device (p < 0.05 for all). CONCLUSION: Adaptation of immobilization device can improve overall image quality with decreased motion artifact and improved centering and timing with even shot number, mean fluoroscopic time with decreased mean DAP value and effective dose.

Age-dependent reference values of the thyroid gland in pediatric population; from routine computed tomography data.

PURPOSE: To evaluate age-dependent reference values for measurements of the thyroid gland in pediatric patients. METHOD: In total 425 chest and neck computed tomography images of pediatric patients without pathology of the thyroid gland were retrospectively reviewed. Measurements of the thyroid gland were obtained in three dimensions (width, depth, length). The total volume was the sum of volumes of each lobe. Measurements were compared among the six groups according to age from 0 to 18 years. RESULTS: There were moderate to strong positive linear correlations between age and all values (r = 0.58-0.82, all p < 0.001). The total volume of the thyroid gland showed a strong positive linear correlation with the three linear measurements of each lobe (all r > 0.7, all p < 0.001). Among these measurements, the depth of the right lobe showed the highest Pearson correlation coefficient with the total volume of the thyroid gland (r = 0.859). CONCLUSION: The depth of right lobe could be a representative measurement of total thyroid gland volume, similar to prior findings in adults.

Adenovirus pneumonia treated with Cidofovir in an immunocompetent high school senior.

Most adenovirus infections are self-limiting in immunocompetent individuals. Here, we report a case of adenovirus pneumonia in a 17-year-old immunocompetent male. He was admitted to our emergency room complaining of a febrile sense, cough, and diarrhea for four days. Crackles in the left lung and a high fever (40.7 °C) were revealed. Initial chest X-ray and computed tomography images showed consolidation in the left lung. We immediately started empirical antibiotic treatment, but his clinical symptoms and pneumonic consolidation in radiography had not improved by hospital day three. Because adenovirus was detected in his sputum using RT-PCR, he was administered Cidofovir. After 24 h of Cidofovir treatment, the symptoms and fever subsided, and the consolidation in his X-ray was significantly reduced by hospital day nine. The early administration of Cidofovir could be beneficial for the treatment of adenovirus infection in immunocompetent patients.

Effect of low tube voltage and low iodine concentration abdominal CT on image quality and radiation dose in children: preliminary study.

PURPOSE: To evaluate the image quality of a double-low protocol (low tube voltage and low iodine concentration) for abdominal CT in children. MATERIALS AND METHODS: The double-low protocol was compared to the conventional protocol in pediatric patients weighing less than 40 kg from May 2016 to December 2016. Double-low protocol (Group A, n = 18): tube voltage, 70 kVp; and iodine concentration,: 250 mgI/mL versus Conventional protocol (Group B, n = 13): tube voltage, 80-100 kVp; and iodine concentration, 350 mgI/mL. Mean attenuation, noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) were compared between the two groups. Image contrast, noise, beam-hardening artifacts, and overall image quality were subjectively scored. Reader performance for correctly differentiating two groups by visual assessment was evaluated. Radiation dose and total iodine load were recorded. RESULTS: The mean attenuations of the portal vein and liver and the mean image noise in Group A were higher than in Group B (p = 0.04, 0.03, 0.004, respectively). The mean SNR and CNR of the main portal vein and liver were lower in Group A without any statistically significant difference. There were no statistically significant differences between the two groups in qualitative analysis (image contrast, image noise, and overall image quality) with substantial agreement between the reviewers (weighted kappa values; 0.59-0.76). Significantly diminished radiation dose and iodine load were observed in Group A compared with Group B (25.0%, 36.8% reduction; p = 0.007, 0.006, respectively). CONCLUSION: The double-low protocol was feasible for pediatric abdominal CT and reduced both radiation dose and iodine load, while maintaining image quality.