An MRI system for imaging neonates in the NICU: initial feasibility study

Background

Transporting premature infants from a neonatal intensive care unit (NICU) to a radiology department for MRI has medical risks and logistical challenges.

Objective

To develop a small 1.5-T MRI system for neonatal imaging that can be easily installed in the NICU and to evaluate its performance using a sheep model of human prematurity.

Materials and methods

A 1.5-T MRI system designed for orthopedic use was adapted for neonatal imaging. The system was used for MRI examinations of the brain, chest and abdomen in 12 premature lambs during the first hours of life. Spin-echo, fast spin-echo and gradient-echo MR images were evaluated by two pediatric radiologists.

Results

All animals remained physiologically stable throughout the imaging sessions. Animals were imaged at two or three time points. Seven brain MRI examinations were performed in seven different animals, 23 chest examinations in 12 animals and 19 abdominal examinations in 11 animals. At each anatomical location, high-quality images demonstrating good spatial resolution, signal-to-noise ratio and tissue contrast were routinely obtained within 30?min using standard clinical protocols.

Conclusion

Our preliminary experience demonstrates the feasibility and potential of the neonatal MRI system to provide state-of-the-art MRI capabilities within the NICU. Advantages include overall reduced cost and site demands, lower acoustic noise, improved ease of access and reduced medical risk to the neonate.     

Incidental pineal cysts in children who undergo 3-T MRI

Background

Pineal cysts, both simple and complex, are commonly encountered in children. More cysts are being detected with MR technology; however, nearly all pineal cysts are benign and require no follow-up.

Objective

To discover the prevalence of pineal cysts in children at our institution who have undergone high-resolution 3-T MRI.

Materials and methods

We retrospectively reviewed 100 consecutive 3-T brain MRIs in children ages 1 month to 17 years (mean 6.8 ± 5.1 years). We evaluated 3-D volumetric T1-W imaging, axial T2-W imaging, axial T2-W FLAIR (fluid attenuated inversion recovery) and coronal STIR (short tau inversion recovery) sequences. Pineal parenchymal and cyst volumes were measured in three planes. Cysts were analyzed for the presence and degree of complexity.

Results

Pineal cysts were present in 57% of children, with a mean maximum linear dimension of 4.2 mm (range 1.5–16 mm). Of these cysts, 24.6% showed thin septations or fluid levels reflecting complexity. None of the cysts demonstrated complete T2/FLAIR signal suppression. No cyst wall thickening or nodularity was present. There was no significant difference between the ages of children with and without cysts. Cysts were more commonly encountered in girls than boys (67% vs. 52%; P?=?0.043). There was a slight trend toward increasing pineal gland volume with age.

Conclusion

Pineal cysts are often present in children and can be incidentally detected by 3-T MRI. Characteristic-appearing pineal cysts in children are benign, incidental findings, for which follow-up is not required if there are no referable symptoms or excessive size.     

High success rates of sedation-free brain MRI scanning in young children using simple subject preparation protocols with and without a commercial mock scanner–the Diabetes Research in Children Network (DirecNet) experience

Background

The ability to lie still in an MRI scanner is essential for obtaining usable image data. To reduce motion, young children are often sedated, adding significant cost and risk.

Objective

We assessed the feasibility of using a simple and affordable behavioral desensitization program to yield high-quality brain MRI scans in sedation-free children.

Materials and methods

222 children (4–9.9 years), 147 with type 1 diabetes and 75 age-matched non-diabetic controls, participated in a multi-site study focused on effects of type 1 diabetes on the developing brain. T1-weighted and diffusion-weighted imaging (DWI) MRI scans were performed. All children underwent behavioral training and practice MRI sessions using either a commercial MRI simulator or an inexpensive mock scanner consisting of a toy tunnel, vibrating mat, and video player to simulate the sounds and feel of the MRI scanner.

Results

205 children (92.3%), mean age 7?±?1.7 years had high-quality T1-W scans and 174 (78.4%) had high-quality diffusion-weighted scans after the first scan session. With a second scan session, success rates were 100% and 92.5% for T1-and diffusion-weighted scans, respectively. Success rates did not differ between children with type 1 diabetes and children without diabetes, or between centers using a commercial MRI scan simulator and those using the inexpensive mock scanner.

Conclusion

Behavioral training can lead to a high success rate for obtaining high-quality T1-and diffusion-weighted brain images from a young population without sedation.     

Safety and adverse effects during 24 hours after contrast-enhanced MRI with gadobenate dimeglumine (MultiHance®) in children

Background

Gadolinium-based MR contrast agents have long been considered safe for routine diagnostic imaging. However, the advent of nephrogenic systemic fibrosis (NSF) among certain patients with severe renal insufficiency has brought the issue of safety into question. Nowhere is safety of greater concern than among children who frequently require multiple contrast-enhanced MRI examinations over an extended period of time.

Objective

To retrospectively evaluate the safety of gadobenate dimeglumine for contrast-enhanced (CE) MRI across a range of indications.

Materials and methods

Two hundred pediatric inpatients (age: 4 days to 15 years) underwent CE MRI as part of clinical routine. The children received a gadobenate dimeglumine dose of either 0.05 mmol/kg body weight (liver, abdominal imaging, musculoskeletal imaging, brain and other rare indications) or 0.1 mmol/kg bodyweight (cardiovascular imaging, MR-urography). Young (< 8 years) children with congenital heart disease were intubated and underwent MRA evaluation with controlled ventilation. Monitoring for adverse events was performed for at least 24 h after each gadobenate dimeglumine injection. Depending on clinical necessity, laboratory measurements and, in some cases, vital sign and ECG determinations were made before and after contrast injection. Safety was evaluated by age group, indication and dose administered.

Results

No clinically adverse events were reported among children who had one MRI scan only or among children who had several examinations. There were no changes in creatinine or bilirubin levels even in very young children.

Conclusions

No adverse events were recorded during the first 24 h following administration of gadobenate dimeglumine in 200 children.     

MRI predictors of treatment response for perianal fistulizing Crohn disease in children and young adults

Background

Magnetic resonance imaging (MRI) is considered the imaging standard for diagnosis and characterization of perianal complications associated with Crohn disease in children and adults.

Objective

To define MRI criteria that could act as potential predictors of treatment response in fistulizing Crohn disease in children, in order to guide more informed study interpretation.

Materials and methods

We performed a retrospective database query to identify all children and young adults with Crohn disease who underwent serial MRI studies for assessment of perianal symptoms between 2003 and 2010. We examined imaging features of perianal disease including fistula number, type and length, presence and size of associated abscess, and disease response/progression on follow-up MRI. We reviewed imaging studies and electronic medical records. Statistical analysis, including logistic regression, was performed to associate MR imaging features with treatment response and disease progression.

Results

We included 36 patients (22 male, 14 female; age range 8–21 years). Of these, 32 had a second MRI exam and 4 had clinical evidence of complete response, obviating the need for repeat imaging. Of the parameters analyzed, presence of abscess, type of fistula according to the Parks classification, and multiplicity were not predictors of treatment outcome. Maximum length of the dominant fistula and aggregate fistula length in the case of multiple fistulae were the best predictors of treatment outcome. Maximum fistula length <2.5 cm was a predictor of treatment response, while aggregate fistula length ≥2.5 cm was a predictor of disease progression.

Conclusion

Perianal fistula length is an important imaging feature to assess on MRI of fistulizing Crohn disease.     

Clinical safety of 3-T brain magnetic resonance imaging in newborns

Background

The effects and potential hazards of brain magnetic resonance imaging (MRI) at 3 T in newborns are debated.

Objective

Assess the impact of 3-T MRI in newborns on body temperature and physiological parameters.

Material and methods

Forty-nine newborns, born preterm and at term, underwent 3-T brain MRI at term-corrected age. Rectal and skin temperature, oxygen saturation and heart rate were recorded before, during and after the scan.

Results

A statistically significant increase in skin temperature of 0.6 °C was observed at the end of the MRI scan (P<0.01). There was no significant changes in rectal temperature, heart rate or oxygen saturation.

Conclusion

Core temperature, heart rate and oxygen saturation in newborns were not affected by 3-T brain MR scanning.

     

Congenital dacryocystocele: prenatal MRI findings

Background

Congenital dacryocystocele can be diagnosed prenatally by imaging. Prenatal MRI is increasingly utilized for fetal diagnosis.

Objective

To present the radiological and clinical features of seven fetuses with congenital dacryocystocele diagnosed with prenatal MRI.

Materials and methods

The institutional database of 1,028 consecutive prenatal MR examinations performed during a period of 4 years was reviewed retrospectively. The cases of congenital dacryocystocele were identified by reading the report of each MRI study.

Results

The incidence of dacryocystocele diagnosed with prenatal MRI was 0.7% (n?=?7/1,028). The dacryocystocele was bilateral in three fetuses. Mean gestational age at the time of diagnosis was 31 weeks. The indication for prenatal MRI was the presence or the suspicion of central nervous system abnormality in six fetuses and diaphragmatic hernia in one. Dacryocystocele was associated with an intranasal cyst in six of ten eyes. Prenatal sonography revealed dacryocystocele in only two of seven fetuses. Of eight eyes with postnatal follow-up, four did not have any lacrimal symptoms.

Conclusion

Prenatal MRI can delineate congenital dacryocystocele more clearly and in a more detailed fashion than ultrasonography. Presence of dacryocystocele was symptomatic in only 50% of our patients, supporting that prenatal diagnosis of dacryocystocele might follow a benign course.     

Comparison of MR and fluoroscopic mucous fistulography in the pre-operative evaluation of infants with anorectal malformation: a pilot study

Background

Anorectal malformations are often associated with rectal pouch fistulas. Surgical correction requires accurate evaluation of the presence and position of such fistulas. Fluoroscopy is currently the chosen modality for the detection of fistulas. The role of MRI is unexplored.

Objective

To compare the diagnostic accuracy of MR versus fluoroscopic fistulography in the pre-operative evaluation of infants with anorectal malformation.

Materials and methods

We conducted a pilot study of infants requiring defunctioning colostomy for initial management of anorectal malformation. Dynamic sagittal steady-state free-precession MRI of the pelvis was acquired during introduction of saline into the mucous fistulas. Findings were compared among MR fistulography, fluoroscopic fistulography and intraoperative inspection.

Results

Eight children were included. Median age at fistulography was 15 weeks, inter-quartile range 13–20 weeks; all were boys. There was full agreement among MR fistulography, fluoroscopic fistulography and surgical findings.

Conclusion

The pilot data suggest that MR fistulography is promising in the pre-operative evaluation of children with anorectal malformation.     

Ganglion cysts in the paediatric wrist: magnetic resonance imaging findings

Background

The majority of published literature on ganglion cysts in children has been from a surgical perspective, with no dedicated radiologic study yet performed.

Objective

Our aim was to assess the magnetic resonance (MR) imaging appearance of ganglion cysts in a series of paediatric MR wrist examinations.

Materials and methods

Ninety-seven consecutive paediatric MR wrist examinations were retrospectively reviewed for the presence of ganglion cysts. Only those studies with wrist ganglia were included. Cysts were assessed for location, size, internal characteristics and secondary effect(s).

Results

Forty-one ganglion cysts (2–32 mm in size) were seen in 35/97 (36%) patients (24 female, 11 male), mean age: 13 years 11 months (range: 6 years 3 months-18 years). The majority were palmar (63.4%) with the remainder dorsal. Of the cysts, 43.9% were related to a wrist ligament(s), 36.6% to a joint and 17.1% to the triangular fibrocartilage complex. Of the patients, 91.4% had wrist symptoms: pain (n=29, 82.9%), swelling (n=7, 20%) and/or palpable mass (n=4, 11.4%); 71.4% patients had significant additional wrist abnormalities.

Conclusion

Ganglion cysts were frequently found in children referred for wrist MRI.     

The patellofemoral joint: do age and gender affect skeletal maturation of the osseous morphology in children?

Background

The osseous morphology of the patellofemoral joint is an independent factor that affects the biomechanics of patellofemoral instability.

Objective

The purpose of this study is to determine age- and gender-related differences in the osseous morphology of the patellofemoral joint in children during skeletal maturation.

Materials and methods

This study was approved by the institutional review board and was HIPAA-compliant. We included 97 children and young adults (age range 5–22 years; 51 girls and 46 boys, mean ages 14.3 years and 13.7 years, respectively). We studied 1.5-T knee MR exams, measuring the osseous morphology of the patellofemoral joint (lateral trochlear inclination, trochlear facet asymmetry, trochlear depth, patellar height ratio, tibial tubercle-trochlear groove distance, and lateral patellofemoral angle) for each MR exam. We compared measurements to published values for patellofemoral instability. Physeal patency (open or closing/closed) was determined on MR. We assessed the associations between MR osseous measurements and gender, age and physeal patency using Wilcoxon rank sum test and least square means regression models.

Results

The osseous patellofemoral joint morphology measurements were all within a normal range. There were no significant correlations between MR osseous measurements and age, gender or physeal patency.

Conclusion

During skeletal maturation, age and gender do not affect the osseous morphology or congruency of the patellofemoral joint.     

Accuracy of abdominal ultrasound and MRI for detection of Crohn disease and ulcerative colitis in children

Background

Endoscopy is currently the primary diagnostic technique for inflammatory bowel disease (IBD) in children.

Objective

To assess the accuracy of US and dynamic contrast-enhanced MRI for diagnosing inflammatory bowel disease and for distinguishing Crohn disease and ulcerative colitis in comparison to a reference standard.

Materials and methods

Consecutive children with suspected IBD underwent diagnostic workup including ileocolonoscopy and upper gastrointestinal endoscopy as the reference standard, abdominal US, and MR enterography and colonography at 3 T. The protocol included a dynamic contrast-enhanced 3-D sequence. Sensitivity, specificity and kappa values were calculated for one ultrasonographer and two MRI observers.

Results

We included 28 children (15 boys) with mean age 14 years (range 10–17 years). The diagnosis was IBD in 23 children (72%), including 12 with Crohn disease, 10 with ulcerative colitis and 1 with indeterminate colitis. For the diagnosis of inflammatory bowel disease the sensitivity was 55% for US and 57% (both observers) for MR entero- and colonography, and the specificity was 100% for US and 100% (observer 1) and 75% (observer 2) for MR entero- and colonography. Combined MRI and US had sensitivity and specificity of 70% and 100% (observer 1) and 74% and 80% (observer 2), respectively. With the addition of a dynamic contrast-enhanced MR sequence, the sensitivity increased to 83% and 87%. US and MRI could only distinguish between Crohn disease and ulcerative colitis when terminal ileum lesions were present.

Conclusion

US and MR entero- and colonography have a high accuracy for diagnosing inflammatory bowel disease in children but cannot be used to distinguish Crohn disease and ulcerative colitis.     

Mortality and Morbidity in Extremely Low Birth Weight (ELBW) Infants in a Neonatal Intensive Care Unit

Objective

To determine the morbidity and mortality in ELBW babies till discharge from a Neonatal Intensive Care Unit (NICU).

Methods

This study was a prospective observational study conducted in a 40 bed well equipped level III care NICU between 01.12.2006 and 30.04.2008. All ELBW babies admitted during this period were assessed for morbidities and interventions required during NICU stay and for their outcome like survival or death.

Results

The survival rate of 87 ELBW babies admitted during this period was 56.1 %. Pulmonary hemorrhage was the commonest cause of death (25 %) followed by respiratory distress syndrome (22.5 %), intraventricular hemorrhage (22.5 %) and sepsis (20 %). Significantly higher number of non-survivors were <750 g at birth (p?=?0.0001) and <28 wk gestation (p?=?0.0001). Small for gestational babies had better chances of survival compared to those appropriate for gestational age (p?=?0.005). RDS (67.8 %), probable sepsis (62.1 %) and hyperbilirubinemia (59.8 %) were the most frequent morbidities. Conventional ventilation (72.4 %) and nasal CPAP(48.3 %) were the commonest respiratory interventions. Surfactant replacement therapy was required in 47.1 % babies.

Conclusions

ELBW babies have a major contribution to mortality in a NICU. Babies with birth weight <750 g and gestation <28 wk have poor survival. RDS, pulmonary hemorrhage, IVH and sepsis are the common causes of death while RDS, sepsis and hyperbilirubinemia are the most common morbidities.     

The Gini coefficient: a methodological pilot study to assess fetal brain development employing postmortem diffusion MRI

Background

Diffusion-weighted imaging (DWI) is important in the assessment of fetal brain development. However, it is clinically challenging and time-consuming to prepare neuromorphological examinations to assess real brain age and to detect abnormalities.

Objective

To demonstrate that the Gini coefficient can be a simple, intuitive parameter for modelling fetal brain development.

Materials and methods

Postmortem fetal specimens(n?=?28) were evaluated by diffusion-weighted imaging (DWI) on a 3-T MRI scanner using 60 directions, 0.7-mm isotropic voxels and b-values of 0, 150, 1,600 s/mm². Constrained spherical deconvolution (CSD) was used as the local diffusion model. Fractional anisotropy (FA), apparent diffusion coefficient (ADC) and complexity (CX) maps were generated. CX was defined as a novel diffusion metric. On the basis of those three parameters, the Gini coefficient was calculated.

Results

Study of fetal brain development in postmortem specimens was feasible using DWI. The Gini coefficient could be calculated for the combination of the three diffusion parameters. This multidimensional Gini coefficient correlated well with age (Adjusted R²?=?0.59) between the ages of 17 and 26 gestational weeks.

Conclusions

We propose a new method that uses an economics concept, the Gini coefficient, to describe the whole brain with one simple and intuitive measure, which can be used to assess the brain’s developmental state.     

Imaging features of juxtacortical chondroma in children

Background

Juxtacortical chondroma is a rare benign bone lesion in children. Children usually present with a mildly painful mass, which prompts diagnostic imaging studies. The rarity of this condition often presents a diagnostic challenge. Correct diagnosis is crucial in guiding surgical management.

Objective

To describe the characteristic imaging findings of juxtacortical chondroma in children.

Materials and methods

We identified all children who were diagnosed with juxtacortical chondroma between 1998 and 2012. A single experienced pediatric radiologist reviewed all diagnostic imaging studies, including plain radiographs, CT, MR and bone scans.

Results

Seven children (5 boys and 2 girls) with juxtacortical chondroma were identified, ranging in age from 6 years to 16 years (mean 12.3 years). Mild pain and a palpable mass were present in all seven children. Plain radiographs were available in 6/7, MR in 7/7, CT in 4/7 and skeletal scintigraphy in 5/7 children. Three lesions were located in the proximal humerus, with one each in the distal radius, distal femur, proximal tibia and scapula. Radiographic and CT features deemed highly suggestive of juxtacortical chondroma included cortical scalloping, underlying cortical sclerosis and overhanging margins. MRI features consistent with juxtacortical chondroma included isointensity to skeletal muscle on T1, marked hyperintensity on T2 and peripheral rim enhancement after contrast agent administration. One of seven lesions demonstrated intramedullary extension, and 2/7 showed adjacent soft-tissue edema.

Conclusion

Juxtacortical chondroma is an uncommon benign lesion in children with characteristic features on plain radiographs, CT and MR. Recognition of these features is invaluable in guiding appropriate surgical management.     

MRI for Quantification of Liver and Cardiac Iron in Thalassemia Major Patients: Pilot Study in Indian Population

Objective

To evaluate Magnetic resonance imaging (MRI) as a tool to quantify liver and cardiac iron in Indian population with thalassemia major, and correlate liver and cardiac iron values with that of serum ferritin (SF).

Methods

Fifty patients aged between 8 to 18 y, with thalassemia major on regular blood transfusions and oral iron chelation therapy were enroled in the study. Twenty patients within the same age group, having no history of blood transfusions and no liver or cardiac disease were taken as controls. T2* MRI of heart and liver and SF estimation was done for all the cases as well as controls. All MRI scans were done on a 1.5-T Siemens MRI scanner using body coil.

Results

The mean SF among cases was 2150 ng/ml (SD 2179). Significant correlation was found in patients between liver iron concentration (LIC, mean 15) and SF levels (r = 0.522; p < 0.001), and also significant but weaker correlation was found in patients between myocardial iron concentration (MIC, mean 1.3) and SF levels (r = 0.483; p < 0.001). Seventeen (34%) patients had a SF of <1000 ng/ml. Of these, 11 and 3 patients respectively had LIC and MIC more than normal range.

Conclusions

T2* MRI is a valuable non-invasive tool for quantification of liver and cardiac iron deposition in patients with thalassemia major. It can demonstrate high LIC and MIC, even though the targeted SF levels are low in thalassemia, indicating the need for escalation of the chelation therapy. This needs to be confirmed on full-fledged larger prospective studies.

     

Improvement of survival in infants with congenital diaphragmatic hernia in recent years: effect of ECMO availability and associated factors

Background/Purpose

Survival of patients with congenital diaphragmatic hernia (CDH) depends both on non-modifiable congenital conditions and on modifiable pre and postnatal management. ECMO improves survival up to 80% in neonates with CDH in the best ECMO centers worldwide. The first Neonatal ECMO Program in Chile was started in our University in 2003. Our objective is to determine the impact of a Neonatal ECMO Program in a level III NICU on newborns with CDH.

Methods

Data of all newborns with CDH admitted to our NICU was separated into two groups: pre ECMO (1996–2003) and ECMO (2003–2007). Crude and adjusted odds ratios for 24 months survival were estimated by logistic regression.

Results

Data of 46 newborns with CDH was analysed, 20 in the pre ECMO and 26 in the ECMO period. Patient characteristics were similar in both groups; however, 24-month survival increased significantly from 25% (5/20) in the pre ECMO period to 77% (20/26) in the ECMO period (P = 0.001). Adjusted odds ratios for 24-month survival were 26.98 for OI ≤ 40, 7.58 for 5 min Apgar ≥ 7 and 17.5 for ECMO availability.

Conclusions

The establishment of an ECMO program was associated with a significant increase in long-term survival for infants with CDH.     

Non Benign Neonatal Arrhythmias Observed in a Tertiary Neonatal Intensive Care Unit

Objective

To analyze non benign neonatal arrhythmias (NA) observed in a tertiary neonatal intensive care unit (NICU).

Methods

From June 2006 through July 2011, newborns admitted to the NICU for NA or diagnosed as NA after hospitalization were evaluated retrospectively. The newborns with non benign NA were included in the study.

Results

During the study period, the incidence of non-benign NA was 0.7 % (n?=?55/7880). The mean age at diagnosis was 16.7?±?1.8 d ranging from 1 d to 90 d. The most common type was supraventricular arrhythmia (SVT) with an incidence of 0.3 %. Univariate analyses showed that there were significant differences between the survived and died infants according types of congenital heart disease (CHD), electrolyte imbalance, and arrhythmias. The mortality rates were higher among infants with obstructive type left-to right shunt and common mixing type CHD. The most dangerous type of electrolyte imbalance was hyperkalemia.

Conclusions

Many arrhythmias could not be noticed at neonatal period even in NICU, implying that it is increasingly important for the physician to be aware of the etiology, development, and natural history of these arrhythmias.     

Relapse surveillance in AFP-positive hepatoblastoma: re-evaluating the role of imaging

Background

Children with hepatoblastoma routinely undergo repetitive surveillance imaging, with CT scans for several years after therapy, increasing the risk of radiation-induced cancer.

Objective

The purpose of this study was to determine the utility of surveillance CT scans compared to serum alpha-fetoprotein (AFP) levels for the detection of hepatoblastoma relapse.

Materials and methods

This was a retrospective study of all children diagnosed with AFP-positive hepatoblastoma from 2001 to 2011 at a single institution.

Results

Twenty-six children with hepatoblastoma were identified, with a mean age at diagnosis of 2 years 4 months (range 3 months to 11 years). Mean AFP level at diagnosis was 132,732 ng/ml (range 172.8–572,613 ng/ml). Five of the 26 children had hepatoblastoma relapse. A total of 105 imaging exams were performed following completion of therapy; 88 (84%) CT, 8 (8%) MRI, 5 (5%) US and 4 (4%) FDG PET/CT exams. A total of 288 alpha-fetoprotein levels were drawn, with a mean of 11 per child. The AFP level was elevated in all recurrences and no relapses were detected by imaging before AFP elevation. Two false-positive AFP levels and 15 false-positive imaging exams were detected. AFP elevation was found to be significantly more specific than PET/CT and CT imaging at detecting relapse.

Conclusion

We recommend using serial serum AFP levels as the preferred method of surveillance in children with AFP-positive hepatoblastoma, reserving imaging for the early postoperative period, for children at high risk of relapse, and for determination of the anatomical site of clinically suspected recurrence. Given the small size of this preliminary study, validation in a larger patient population is warranted.     

Small-bowel MRI in children and young adults with Crohn disease: retrospective head-to-head comparison of contrast-enhanced and diffusion-weighted MRI

Background

Small-bowel MRI based on contrast-enhanced T1-weighted sequences has been challenged by diffusion-weighted imaging (DWI) for detection of inflammatory bowel lesions and complications in patients with Crohn disease.

Objective

To evaluate free-breathing DWI, as compared to contrast-enhanced MRI, in children, adolescents and young adults with Crohn disease.

Materials and methods

This retrospective study included 33 children and young adults with Crohn disease ages 17?±?3 years (mean ± standard deviation) and 27 matched controls who underwent small-bowel MRI with contrast-enhanced T1-weighted sequences and DWI at 1.5 T. The detectability of Crohn manifestations was determined. Concurrent colonoscopy as reference was available in two-thirds of the children with Crohn disease.

Results

DWI and contrast-enhanced MRI correctly identified 32 and 31 patients, respectively. All 22 small-bowel lesions and all Crohn complications were detected. False-positive findings (two on DWI, one on contrast-enhanced MRI), compared to colonoscopy, were a result of large-bowel lumen collapse. Inflammatory wall thickening was comparable on DWI and contrast-enhanced MRI. DWI was superior to contrast-enhanced MRI for detection of lesions in 27% of the assessed bowel segments and equal to contrast-enhanced MRI in 71% of segments.

Conclusion

DWI facilitates fast, accurate and comprehensive workup in Crohn disease without the need for intravenous administration of contrast medium. Contrast-enhanced MRI is superior in terms of spatial resolution and multiplanar acquisition.