Ophthalmic and Neuroimaging Associations In Optic Nerve Hypoplasia/Septo-Optic-Pituitary Dysplasia.

BACKGROUND: Optic nerve hypoplasia (ONH) and septo-optic-pituitary dysplasia (SOD) are neurodevelopmental disorders associated with congenital visual impairment. Our aim was to investigate associations between several ophthalmic and neuroimaging features in patients with ONH/SOD. METHODS: A retrospective chart and neuroimaging review was performed in patients with ONH/SOD. Ophthalmic signs (e.g., monocular best-corrected visual acuity [BCVA], nystagmus, and strabismus) and neuroimaging data were extracted and their associations were investigated. RESULTS: There were 128 patients (70 males) with ONH/SOD who had neuroimaging. Their mean age at the end of the study was 13.2 (SD: 7.5) years. Ophthalmic data were available on 102 patients (58 males). BCVA varied from normal to no light perception. There were statistically significant associations between: (A) Reduced optic nerve or chiasm size on neuroimaging and more severely impaired BCVA and (B) laterality of the reduced optic nerve or chiasm size on neuroimaging and laterality of: (1) The eye with reduced BCVA, (2) small optic disc size, and (3) RAPD, if present (p ≤ 0.0002 each). The presence of symmetrically small optic nerves on MRI was significantly more common in patients with nystagmus than when nystagmus was absent (N = 96, 75% vs. 38.6%, p < 0.0001). The presence of neuronal migration disorders, their type and laterality were not associated with BCVA and laterality of the reduced BCVA. CONCLUSION: The functional and structural associations in ONH are consistent with the impaired visual function that results from the hypoplastic anterior visual pathways. However, these associations were not perfectly concordant making prediction of adult BCVA challenging in these patients.

The utility of point-of-care ultrasound protocol to confirm central venous catheter placement in the preterm infant.

Central vascular access is frequently required for preterm infants. Confirmation of positioning of central line is typically on chest and abdominal radiographs; POCUS is a relatively novel diagnostic method. Misdiagnosis is the main concern limiting use of this modality. The aim of this study is to validate our standard protocol accuracy in locating the central catheter position by correlating catheter position as determined by POCUS with radiographs. Premature babies < or equal to 30 weeks gestation who had peripheral central lines or surgical lines were enrolled. Confirmation of line position by radiographs was compared to images obtained through a specific US protocol technique. The operator of US exam was blinded to the radiograph findings. All images were reviewed by two radiologists who were blinded to the radiograph findings. 35 central line placements were assessed. 22 lines were inserted in the UL, and 13 were inserted in the LL with a total of 91 ultrasound scans and radiographs. The position of the line was interpreted as normal in 79/91 scans with interpreter reliability of [Formula: see text]=0.778 (p < 0.001), sensitivity of 0.83 and specificity of 0.96, and positive predictive value of 0.77 and negative predictive value of 0.97. There was no significant difference between the ultrasound interpretation and the radiograph interpretation of UL and LL.  Conclusion: The protocol of POCUS that we propose is a reliable tool for assessing the central line positions in preterm infants. What is Known: • POCUS is a reliable tool assessing the central line positions in preterm infants. What is New: • The protocol of POCUS that we propose is a reliable tool for assessing the central line positions in preterm infants.

Neuroimaging Features in Children with Optic Nerve Hypoplasia and Septo-Optic-Pituitary Dysplasia.

BACKGROUND: Optic nerve hypoplasia (ONH) and septo-optic-pituitary dysplasia (SOD) are common causes of congenital visual impairment. Our primary aim was to investigate the prevalence of abnormal neuroimaging features in patients with these disorders in Manitoba, Canada, and compare them with published reports. METHODS: A retrospective neuroimaging review was performed in patients resident in Manitoba with ONH/SOD. RESULTS: There were 128 patients (M = 70) with ONH/SOD who had neuroimaging. Their mean age (SD) at the end of the study was 13.2 (7.5) years. Males were significantly more likely to have bilateral ONH and a small optic chiasm size, while females were more likely to have a left ONH and a small left optic chiasm size on neuroimaging (p = 0.049). ONH and small optic chiasm size were seen in most patients on neuroimaging. Absent septum pellucidum was noted in 40%, small pituitary gland size in 28%, neuronal migration disorders (NMD) in 20% (>1 type and bilateral in 13 cases), corpus callosum abnormalities were present in 9%, while olfactory bulbs-tracts and olfactory sulci were absent in 8.6% of cases. Unilateral ONH was not significantly associated with other structural brain abnormalities, while NMD were significantly associated with other midline brain abnormalities including a symmetrically small optic chiasm size. CONCLUSION: The prevalence of structural neuroimaging abnormalities in our cohort with ONH/SOD was generally in the same range reported in other studies with corpus callosum abnormalities being relatively less common in our study. Bilateral NMD were relatively common among patients with NMD. The association between sex and ONH laterality requires further study.

A systematic review and meta-analysis of computed tomography in the diagnosis of pediatric foreign body aspiration.

INTRODUCTION: Rigid bronchoscopy remains the gold standard for the diagnosis of foreign body aspiration (FBA) despite high rates of negative bronchoscopies. The use of computed tomography (CT) imaging in the assessment of FBA has recently emerged and could help obviate unnecessary bronchoscopy in these patients. The aim of this study is to assess the diagnostic accuracy of CT in the diagnosis of pediatric FBA. METHODS: A systematic literature review was conducted to identify studies reporting the use of CT imaging in suspected pediatric FBA. The search included published articles in Ovid MEDLINE, Ovid EMBASE, PubMed MEDLINE and Web of Science. The search strategy included all articles from inception of the database to January 2021. Manuscripts were reviewed and graded for quality using the QUADAS-2 tool. Subgroup analyses based on the use of virtual bronchoscopy (VB) and sedation was conducted. A meta-analysis evaluating the use of VB in the diagnosis of FBA was also conducted. RESULTS: Sixteen manuscripts met all inclusion criteria. In total, 2056 pediatric patients ranging from 0.3 to 15 years underwent CT for suspected FBA. The sensitivity and specificity of CT were 98.8% and 96.6%, respectively. VB was used in 71.4% (1391/1948) of patients while sedation during CT was required in 70.2% (1263/1800) of patients. Radiation dosing ranged from 0.04 to 2 mSv, 0.99-59.1 mGy-cm and 0.03-16.99 mGy. CONCLUSION: CT can accurately diagnose pediatric FBA and can help decrease the rate of unnecessary bronchoscopies with an acceptable dose of radiation.

Imaging findings of pulmonary blastomycosis in pediatric patients.

Blastomycosis is caused by Blastomyces dermatitidis, a thermally dimorphic fungus that lives in the form of spores in the soil in North America. The main mode of transmission is through the inhalation of these spores. Despite the importance of knowing the imaging characteristics of blastomycosis given the suggested high rates of dissemination in symptomatic children, a paucity of literature focuses on the imaging patterns of blastomycosis in the pediatric population. In this review, we describe the main imaging findings of pediatric pulmonary blastomycosis and briefly review extrapulmonary manifestations of the disease. Familiarity with these imaging manifestations is important to aid in rapid diagnosis.

Radiation dose reduction for chest radiography of infants in intensive care units using a high peak kilovoltage-technique.

BACKGROUND: Chest radiography is an important tool in the care of infants in intensive care units. Image optimization must be monitored to minimize radiation exposure in this susceptible population. OBJECTIVE: To examine the use of a high tube peak kilovoltage technique to achieve radiation dose reduction while maintaining adequate image quality. MATERIALS AND METHODS: A retrospective study was conducted. Radiation doses of chest radiographs performed in the pediatric intensive care units in our institution were calculated. The radiographs were divided into two groups based on the value of the peak kilovoltage used: above and below 60 kilovolts (kV). Image quality was blindly assessed by two fellowship-trained pediatric radiologists. Air kerma, effective dose and quality score for the high versus the low peak kilovoltage group were compared and analyzed. RESULTS: The study included 376 radiographs. One hundred and seven radiographs were performed using peak kilovoltage values equal to or above 60 kV and 269 radiographs were performed using values under 60 kV. The average air kerma for the lower peak kilovoltage group was 56.6 microgray (µGy) (30.7-81.9) vs. 22.9 µGy (11.8-34.4) for the higher peak kilovoltage group (P<0.0001). The mean difference in effective dose between the groups was 11.68 (P<0.0001). The mean difference for the quality score was 0.06 (±0.03, P=0.10), not statistically significant. CONCLUSION: A high peak kilovoltage technique may enable a statistically significant radiation dose reduction without compromising the diagnostic value of the image.

Thromboangiitis Obliterans (Buerger's Disease) in an Adolescent Male.

Arterial occlusive disease of the limb is very rare in children. Buerger's disease (BD) is a nonatherosclerotic, segmental inflammatory arteritis affecting the small and medium-sized vessels of the extremities. We report BD in a 16-year-old male presenting with arterial insufficiency of left foot and history of smoking cigarettes and cannabis for 2 years. BD was diagnosed based on history of smoking in combination with clinical, laboratory, and radiologic findings. Pediatric hemato-oncologists should consider BD in the differential diagnosis in adolescents who smoke cigarettes and/or cannabis and present with vascular insufficiency of the hands and/or feet.

Disseminated Echinococcus multilocularis Infection without Liver Involvement in Child, Canada, 2018.

An immunocompetent child in Canada received a diagnosis of disseminated alveolar Echinococcus multilocularis infection. The case lacked typical features of liver involvement and was possibly related to a rare congenital portosystemic shunt. We summarize the rapidly evolving epidemiology of E. multilocularis parasites in Canada.

Imaging Patterns of Pediatric Pulmonary Blastomycosis.

OBJECTIVE: The objective of our study was to characterize and update the radiologic patterns of pediatric pulmonary blastomycosis, and correlate the radiologic patterns with patient age. MATERIALS AND METHODS: Patients 0-18 years old with pulmonary blastomycosis who underwent chest imaging from 2005 to 2016 were included in this study. The following data were collected: age, sex, clinical information, and imaging findings including presence of extrapulmonary involvement and scarring on follow-up examinations. Concordance between radiography and CT was analyzed. RESULTS: Thirty-six patients (28 boys and eight girls) ranging in age from 3 months to 17 years (mean, 10.5 years) were identified. Consolidation was found in 94.4% of patients and was unilateral in 76.5% of cases and bilateral in 23.5%. Upper (70.6%) and middle (47.1%) lobes were more frequently involved. Air bronchograms were identified in 76.5% of patients with consolidations, masslike consolidation was found in 55.9%, cavitation in 38.2%, and bubbly pattern (i.e., multiple small cavities) in 32.4%. In all patients younger than 5 years, consolidations involved multiple lobes. In 67.6% of patients, consolidations were associated with the following additional pulmonary or pleural abnormalities: pulmonary nodules (50% of patients), diffuse patchy opacification (26.5%), reticulonodular pattern (41.2%), atelectasis (5.9%), pleural effusion (20.6%), and hilar lymphadenopathy (23.5%). Pulmonary scarring was found in 70.4% of patients. Five patients had extrapulmonary involvement. The concordance between radiography and CT was excellent for location and extension of consolidation and diagnosis of cavitation, bubbly pattern, and nodules. CONCLUSION: The most common pattern of lung involvement from pulmonary blastomycosis in our series was a combination of consolidations with bilateral lung nodules and reticulonodular opacification.

Cerebellar radiological abnormalities in children with neurofibromatosis type 1: part 2 - a neuroimaging natural history study with clinical correlations.

BACKGROUND: Focal abnormal signal intensities (FASI) on brain MRI occur commonly in patients with neurofibromatosis type 1 (NF1). The natural history of cerebellar FASI and their correlation with clinical features have not been studied comprehensively. Our aims are to describe the natural history of cerebellar FASI on repeat MRI scans and correlate the findings with the clinical features in children with NF1 and cerebellar FASI. METHOD: A retrospective review of 226 brain MRI scans and hospital charts was performed in 50 patients with cerebellar FASI, who were diagnosed with NF1 during their childhood between 1999 and 2008. RESULTS: Mean age at the end of the study period was 16.1 years. There were 27 males. Mean duration of clinical follow up was 10.1 years. Mean duration between the first and the last MRI was 6.6 years (n = 36, SD: 2.8 years). FASI were rarely confined to the cerebellum. The number of FASI was highest in early childhood and decreased significantly on subsequent MRI scans in most brain regions with the exception of the cerebrum, where a fewer number of patients with a smaller number of FASI were seen. Four patterns of change in FASI size over time were determined, none correlated with the clinical features. CONCLUSIONS: In patients with NF1, the natural history of FASI including their number, age at onset, rate of size changes, and resolution if any, varies by brain region. FASI patterns of change over time showed no clinical correlate.

Cerebellar radiological abnormalities in children with neurofibromatosis type 1: part 1 - clinical and neuroimaging findings.

BACKGROUND: Many children with neurofibromatosis type 1 (NF1) have focal abnormal signal intensities (FASI) on brain MRI, whose full clinical impact and natural history have not been studied systematically. Our aims are to describe the clinical and neuroradiological features in children with NF1 and cerebellar FASI, and report on the natural history of FASI that display atypical features such as enhancement and mass effect. METHOD: A retrospective review of the hospital charts and brain MRIs was performed on children from Manitoba diagnosed between 1999 and 2008 with NF1, who also had cerebellar FASI on MRI. RESULTS: Fifty patients (mean age: 16.1y, minimum-maximum: 6.4 - 30y, 27 M) were identified. Mean duration of follow up was 10.1y. Developmental delay, learning disabilities, tumors, and visual signs occurred commonly. Cerebellar signs were not reported. Mean age of the patients at baseline MRI was 7.8 (SD: 4.5) years. FASI occurred in several brain locations and were rarely confined to the cerebellum. FASI displayed mass effect and enhancement infrequently but were associated with malignancy only once. The number of FASI at baseline MRI was significantly less in patients with attention deficient hyperactivity disorder and more if a first degree relative had NF1 or if they had decreased visual acuity. DISCUSSION: Patients with NF1 and cerebellar FASI do not have motor or consistent non-motor (e.g. developmental delay or learning disabilities) cerebellar features. The number of FASI may correlate with some clinical features. FASI may display enhancement and mass effect but they rarely become malignant.

Centile charts for cranial sutures in children younger than 1 year based on ultrasound measurements.

BACKGROUND: Cranial US allows for the evaluation of premature closure (synostosis) or abnormal widening of the cranial sutures. An understanding of the normal anatomy is required to help define the presence or absence of abnormality. OBJECTIVE: To provide reference for normal ultrasound measurements of cranial sutures during the child's first year. MATERIALS AND METHODS: We included children ages 0 to 12 months who were referred to the hospital during 2011-2013 for radiographic evaluation of cranial sutures. Cranial US study was focused on evaluating the sagittal, coronal, lambdoid and metopic sutures. We measured the hypoechoic gap between the bones (patent suture). Two readers performed the measurements, blinded to clinical indications and previous reports. Estimates of the 10th, 25th, 50th, 75th and 90th percentiles were achieved for ages 1-12 months. RESULTS: Of 129 children whose families consented to cranial US, 11 were excluded because of craniosynostosis and 3 for suboptimal quality of cranial US images. In 115 patients measurements of normal cranial sutures were obtained (75 boys [65%], ages 0.26-11.27 months). For each suture, the suture size decreased significantly with age (P<0.001). Only the metopic suture was noted to close completely toward the end of the first year of age. There were no statistically significant differences in age-related suture size by gender. CONCLUSION: The current patient series represents a reference of percentiles of normal ultrasound measurements of cranial sutures during the first year of age.

Tracking inflammation in the epileptic rat brain by bi-functional fluorescent and magnetic nanoparticles.

Correct localization of epileptic foci can improve surgical outcome in patients with drug-resistant seizures. Our aim was to demonstrate that systemically injected nanoparticles identify activated immune cells, which have been reported to accumulate in epileptogenic brain tissue. Fluorescent and magnetite-labeled nanoparticles were injected intravenously to rats with lithium-pilocarpine-induced chronic epilepsy. Cerebral uptake was studied ex vivo by confocal microscopy and MRI. Cellular uptake and biological effects were characterized in vitro in murine monocytes and microglia cell lines. Microscopy confirmed that the nanoparticles selectively accumulate within myeloid cells in the hippocampus, in association with inflammation. The nanoparticle signal was also detectable by MRI. The in vitro studies demonstrate rapid nanoparticle uptake and good cellular tolerability. We show that nanoparticles can target myeloid cells in epileptogenic brain tissue. This system can contribute to pre-surgical and intra-surgical localization of epileptic foci, and assist in detecting immune system involvement in epilepsy.

Extending the Spectrum of Radiological Findings in Patients With Severe Osteopetrosis and Different Genetic Backgrounds.

PURPOSE: To evaluate radiological findings in a cohort of 22 patients with infantile malignant osteopetrosis in order to establish the correlation between radiological findings and different genetic backgrounds. MATERIALS AND METHODS: Clinical files, genetic analysis results, and radiological examinations of children treated for osteopetrosis with bone marrow transplantation in a referral center in the last 5 years were retrospectively evaluated. The study received institutional review board (IRB) approval. RESULTS: Twenty-two patients were included in the study: 18 males, four females, ages 1 month-9 years 10 months, and the median age was 11 months (mean 23 months). There were 12 patients with different mutations in the TCIRG1 gene, five with mutations in the SNX10 gene, four children harbored RANK mutations, and one patient had a CLCN7 mutation. We noted more severe radiological findings in patients with TCIRG1 and RANK mutations, including fractures, osteopetrorickets, hydrocephalus, and hepatomegaly. Varus deformity of the femoral neck was seen exclusively in patients with a TCIRG1 mutation. CONCLUSIONS: The variable genetic spectrum of osteopetrosis is associated with a variable radiological presentation. These correlations may be helpful for priorities in genetic analysis.

Cranial Ultrasound as a First-Line Imaging Examination for Craniosynostosis.

BACKGROUND: Radiography, typically the first-line imaging study for diagnosis of craniosynostosis, exposes infants to ionizing radiation. We aimed to compare the accuracy of cranial ultrasound (CUS) with radiography for the diagnosis or exclusion of craniosynostosis. METHODS: Children aged 0 to 12 months who were assessed for craniosynostosis during 2011-2013 by using 4-view skull radiography and CUS of the sagittal, coronal, lambdoid, and metopic sutures were included in this prospective study. Institutional review board approval and parental informed consent were obtained. CUS and radiography were interpreted independently and blindly by 2 pediatric radiologists; conflicts were resolved in consensus. Sutures were characterized as closed, normal, or indeterminate. Correlation between CUS and radiography and interreader agreement were examined for each suture. RESULTS: A total of 126 children (82 boys, 64.5%) ages 8 to 343 days were included. All sutures were normal on CUS and radiography in 115 patients (93.7%); craniosynostosis of 1 suture was detected in 8 (6.3%, 5 sagittal, 2 metopic, 1 coronal). In 3 cases the metopic suture was closed (n = 2) or indeterminate on CUS (n = 1) but normally closed on radiography. CUS sensitivity was 100%, specificity 98% (95% confidence interval 94%-100%). Reader agreement was 100% for sagittal, coronal, and lambdoid sutures (κ = 0.80); after consensus, disagreement remained on 3 metopic sutures. CONCLUSIONS: In this series, CUS could be safely used as a first-line imaging tool in the investigation of craniosynostosis, reducing the need for radiographs in young children. Additional assessment may be required for accurate assessment of the metopic suture.

Leukocyte adhesion deficiency type III: clinical features and treatment with stem cell transplantation.

Leukocyte adhesion deficiency type III (LADIII) is an autosomal recessive disorder that presents with a severe leukocyte adhesion defect and a Glanzmann-type thrombocytopathy. Hematopoietic stem cell transplantation (HSCT)--the only definitive treatment for LADIII--appears to have a high rate of complications. In this study, we describe a new group of patients with LADIII, highlighting further clinical and immunologic aspects of this disease, and reevaluating the effectiveness of HSCT for its treatment. The patients had clinical and laboratory findings consistent with LADIII. Molecular analysis confirmed the presence of a mutation in the kindlin-3 gene. HSCT was carried out in 3 patients and was successful in 2. The diagnosis of LADIII should be considered in all patients who present with recurrent infections and a bleeding diathesis, regardless of the leukocyte count. LADIII is a primary immune deficiency, which can be successfully corrected by bone marrow transplantation if applied early in the course of the disease using appropriate conditioning.

Ileocolic versus small-bowel intussusception in children: can US enable reliable differentiation?

PURPOSE: To assess clinical and ultrasonographic (US) criteria that can be used to confidently differentiate ileocolic from small-bowel intussusception. MATERIALS AND METHODS: Institutional review board approval was obtained for this retrospective study, and the need to obtain informed consent was waived. US and clinical data for children given a diagnosis of intussusception in the years 2007 through 2011 were evaluated. The diameters of the intussusception and the inner fat core, the outer bowel wall thickness, and the presence or absence of lymph nodes inside the intussusception and mesentery were noted. The Student t test, the Mann-Whitney test, and the Levene test were used for comparison of parametric variables, while the χ(2) and Fisher exact tests were used for comparison of categoric data. RESULTS: There were 200 cases of intussusception in 174 patients (126 boys, 48 girls; mean age, 17.2 months (range, 0 years to 7 years 1 month); 57 (28.5%) were small-bowel and 143 (71.5%) were ileocolic intussusceptions. Mean lesion diameter was 2.63 cm (range, 1.3-4.0 cm) for ileocolic versus 1.42 cm (range, 0.8-3.0 cm) for small-bowel intussusception (P < .0001). Mean fat core diameter was 1.32 cm (range, 0.6-2.2 cm) for ileocolic versus 0.1 cm (range, 0-0.75 cm) for small-bowel intussusception (P < .0001). The ratio of inner fat core diameter to outer wall thickness was greater than 1.0 in all ileocolic intussusceptions and was less than 1.0 in all small-bowel intussusceptions (P < .0001). Lymph nodes inside the lesion were seen in 128 (89.5%) of the 143 ileocolic intussusceptions versus in eight (14.0%) of the 57 small-bowel intussusceptions (P < .0001). Children with ileocolic intussusception had more severe clinical symptoms and signs, with more vomiting (P = .003), leukocytosis (P = .003), and blood in the stool (P = .00005). CONCLUSION: The presence of an inner fatty core in the intussusception, lesion diameter, wall thickness, the ratio of fatty core thickness to outer wall thickness, and the presence of lymph nodes in the lesion may enable reliable differentiation between ileocolic and small-bowel intussusceptions.

Fast-brain MRI in children is quick, without sedation, and radiation-free, but beware of limitations.

Fast-brain MRI is a promising technique for young children who require anesthesia for conventional MRI; however, poor contrast resolution and the use of one type of pulse sequence only has limitations. We aimed to review and document pitfalls of fast-brain MRI in non-sedated children. Fifty fast-brain MRI studies (Fast Imaging Employing sTeady State Acquistion [FIESTA] protocol; 1.5-Tesla Signa Excite HD, GE HealthCare, Milwaukee, WI, USA) performed between January 2008 and August 2010 in 30 non-sedated patients aged 1 day to 5 years of age (mean: 18 months) were reviewed retrospectively and compared to the most recent MRI or CT scan. The indications were: ventriculoperitoneal (VP) shunt insertion or revision or follow-up (20/50, 40%), postoperative follow-up (9/50, 18%), macrocephaly, ventriculomegaly or congenital malformation (15/50, 30%), complications of prematurity (6/50, 12%). The VP shunt position and size of fluid-filled structures were satisfactorily assessed in all patients. Undetected findings in 7/50 studies (14%) were: venous sinus thrombosis (one patient), subdural hematoma (three), failure to differentiate blood products (two), and limited evaluation of extra-axial collections (one). FIESTA fast-brain MRI provides satisfactory assessment of shunt position and the size of fluid-filled structures, but radiologists should be aware of limitations for depiction of venous sinus thrombosis, and bleeding. Modification of fast-brain protocols appears to be indicated.

Normal CT characteristics of the thymus in adults.

BACKGROUND: The thymus changes with age. Its shape and the proportion of solid tissue and fat vary between individuals, yet there is no comprehensive work describing the size and morphology of the normal thymus on CT. As a result, many adults with some preserved soft tissue in the thymus may undergo extensive work-up to exclude mediastinal tumor. Our aim was to quantify CT characteristics of the normal thymus in an adult population. METHODS: CT chest scans of 194 trauma patients aged 14-78 years (mean 52.6 years), were retrospectively reviewed. The density, volume, shape and predominant side of the thymus were recorded for 56 patients in whom some solid tissue was preserved. Statistical analysis of these characteristics according to the patient age and gender was performed. RESULTS: Thymic density and volume decreased progressively with age. No solid tissue component was seen in the thymus in patients older than 54 years. In the majority of patients, the thymus had an arrowhead shape, with middle position. However, great variability in thymic shape and border were noted. There was a highly significant relationship between density and patient age (p<0.0001). CONCLUSION: We hope that our work will help in the definition of normal thymic CT parameters in adults, help to prevent unnecessary and expensive imaging procedures, and reduce patient exposure to ionizing radiation.