Separate Evaluation of the Ipsilateral and Contralateral MR Fetal Lung Volume in Patients With Congenital Diaphragmatic Hernia.

OBJECTIVE: Our study had two objectives. First, we separately evaluated observed-to-expected MR fetal lung volume (FLV) of lungs ipsilateral and contralateral to a congenital diaphragmatic hernia (CDH). Second, we compared the prognostic value of observed-to-expected MR FLV of the ipsilateral and contralateral lungs with that of observed-to-expected MR FLV of both lungs with respect to survival, need for extracorporeal membrane oxygenation (ECMO), and development of chronic lung disease (CLD). MATERIALS AND METHODS: We evaluated observed-to-expected MR FLV of the lung ipsilateral to the diaphragmatic defect as well as in the contralateral lung in 107 fetuses with isolated CDH. ROC analysis and logistic regression analysis were performed to assess the prognostic value of the observed-to-expected MR FLV for association with outcome. RESULTS: In all fetuses with CDH, values in the ipsilateral (mean observed-to-expected MR FLV ± SD, 9.4% ± 9.6%) and the contralateral lung (mean observed-to-expected MR FLV, 48.9% ± 18.5%; p < 0.0001) were significantly lower than values measured in healthy fetuses. Observed-to-expected MR FLV of both lungs and of the contralateral and ipsilateral lung revealed significant differences regarding survival (p < 0.0001, p < 0.0001, and p = 0.0170, respectively), need for ECMO (p < 0.0001, p < 0.0001, and p = 0.0051, respectively), and development of CLD (p = 0.0004, p = 0.0002, and p = 0.0460, respectively). Compared with the observed-to-expected MR FLV of both lungs, the observed-to-expected MR FLV of the contralateral lung showed a slightly higher prognostic accuracy regarding survival (AUC = 0.859 vs 0.825) and development of CLD (AUC = 0.734 vs 0.732) and a similar prognostic accuracy regarding need for ECMO (AUC = 0.805 vs 0.826). Observed-to-expected MR FLV of the ipsilateral lung did not show good prognostic value regarding survival (AUC = 0.617), need for ECMO (AUC = 0.673), and development of CLD (AUC = 0.636). These AUCs were significantly smaller than the AUCs resulting from the observed-to-expected MR FLV of both lungs (each p < 0.05) and considerably smaller than the AUCs of the observed-to-expected MR FLV of the contralateral lung (each p < 0.10). CONCLUSION: Patients with CDH showed a substantially lower observed-to-expected MR FLV of both lungs compared with healthy fetuses. The observed-to-expected MR FLV of both lungs as well as of the lung contralateral to the CDH were reliable prenatal predictors of survival, need for ECMO, and development of CLD.

Lung Perfusion MRI After Congenital Diaphragmatic Hernia Repair in 2-Year-Old Children With and Without Extracorporeal Membrane Oxygenation Therapy.

OBJECTIVE: In severe cases of congenital diaphragmatic hernia (CDH), extracorporeal membrane oxygenation (ECMO) therapy improves survival. Later on, lung morbidity mainly defines development. The purpose of this study was to investigate whether 2-year-old children who need ECMO therapy after delivery have reduced perfusion MRI values as a sign of more severe lung hypoplasia than do children who do not need ECMO. MATERIALS AND METHODS: After CDH repair, 38 children underwent dynamic contrast-enhanced MRI with a 3D time-resolved angiography with stochastic trajectories sequence. Fifteen (39%) of the children had received ECMO therapy in the neonatal period. Pulmonary blood flow (PBF), pulmonary blood volume (PBV), and mean transit time were calculated for both lungs. In addition, the ratio of ipsilateral to contralateral lung was calculated for all parameters. RESULTS: In all children, those with and those without ECMO requirement, PBF and PBV were significantly reduced on the ipsilateral side (p < 0.05). Children who had received ECMO therapy had significantly reduced PBF and PBV values on the ipsilateral side (p < 0.05) compared with children who had not needed ECMO therapy. The ratios of ipsilateral to contralateral lung for PBF and PBV were also significantly reduced after ECMO. CONCLUSION: Two-year-old children undergoing CDH repair who had needed neonatal ECMO had significantly reduced perfusion MRI values in the ipsilateral lung in comparison with children who had not needed ECMO. Perfusion MRI measurements are associated with the severity of lung hypoplasia and may therefore be helpful in follow-up investigations.

Correlation of Observed-to-Expected MRI Fetal Lung Volume and Ultrasound Lung-to-Head Ratio at Different Gestational Times in Fetuses With Congenital Diaphragmatic Hernia.

OBJECTIVE: The purpose of this study is to compare the observed-to-expected MRI fetal lung volume and the observed-to-expected ultrasound lung-to-head ratio intraindividually for prediction of survival, the need for extracorporeal membrane oxygenation (ECMO) therapy, and the development of chronic lung disease (CLD) at different times of gestation (< 28, 28-32, and > 32 weeks) in fetuses with congenital diaphragmatic hernia (CDH), and to analyze the intraindividual correlation of observed-to-expected MRI fetal lung volume and observed-to-expected ultrasound lung-to-head ratio. MATERIALS AND METHODS: Two hundred one fetuses were included in our study. Observed-to-expected MRI fetal lung volume and observed-to-expected ultrasound lung-to-head ratio were calculated for 270 MRI and ultrasound examinations performed within 72 hours of each other. The prognostic accuracy of observed-to-expected MRI fetal lung volume and observed-to-expected ultrasound lung-to-head ratio was assessed by performing ROC analysis. Correlation was determined using linear regression analysis. RESULTS: The results revealed statistically significant differences between the observed-to-expected MRI fetal lung volume and observed-to-expected ultrasound lung-to-head ratio for the prediction of survival, the need for ECMO therapy, and the development of CLD in fetuses with left-sided CDH (p ≤ 0.0444), with the highest prognostic accuracy for survival (AUC = 0.863). Observed-to-expected MRI fetal lung volume and observed-to-expected ultrasound lung-to-head ratio correlated statistically significantly (p < 0.0001) for left-sided CDH with correlation coefficients (r) of 0.71, 0.71, and 0.56 for early, intermediate, and late times of gestation, respectively. The correlation was not statistically significant at any time for right-sided CDH (p ≥ 0.3947; r ≤ 0.26). CONCLUSION: Observed-to-expected MRI fetal lung volume and observed-to-expected ultrasound lung-to-head ratio are valuable prognostic parameters for prenatal prediction of survival, the need for ECMO therapy, and the development of CLD in fetuses with left-sided CDH at all times of gestation. Observed-to-expected MRI fetal lung volume and observed-to-expected ultrasound lung-to-head ratio correlate statistically significantly for left-sided CDH, and the correlation is best before 32 weeks' gestation, but they do not correlate statistically significantly for right-sided CDH.

Comparison of image quality and radiation dose between an image-intensifier system and a newer-generation flat-panel detector system ­ technical phantom measurements and evaluation of clinical imaging in children.

BACKGROUND: Many image-intensifier fluoroscopy systems have been replaced by flat-panel detectors in recent years. OBJECTIVE: To compare the level of contrast, image resolution and radiation dose between an image-intensifier and a newer-generation flat-panel detector system in a pediatric radiology unit. MATERIALS AND METHODS: We compared two systems ­ a conventional image intensifier and a newer-generation flat-panel system. We measured image quality and radiation dose using a technical phantom. Additionally, we retrospectively compared age-matched fluoroscopic pediatric voiding cystourethrography (n = 15) and upper gastrointestinal investigations (n = 25). RESULTS: In phantom studies image contrast was equal while image resolution was higher and mean radiation dose lower using the flat-panel system (P < 0.0001). In pediatric investigations, mean dose area product was significantly reduced on the flat-panel system for upper gastrointestinal investigation (45 ± 38 µGy*m2 vs. 11 ± 9 µGy*m2; P < 0.0001) and for voiding cystourethrography (18 ± 20 µGy*m2 vs. 10 ± 12 µGy*m2; P = 0.04). CONCLUSION: The newer flat-panel system performs at lower dose levels with equal to better image quality and therefore seems to be the more suitable technique for pediatric fluoroscopy in comparison to image-intensifier systems.

Prenatal MR imaging of congenital diaphragmatic hernias: association of MR fetal lung volume with the need for postnatal prosthetic patch repair.

OBJECTIVE: To assess whether the need for postnatal prosthetic patch repair of the diaphragmatic defect in neonates with a congenital diaphragmatic hernia (CDH) is associated with the antenatal measured observed-to-expected magnetic resonance fetal lung volume (o/e MR-FLV). METHODS: The o/e MR-FLV was calculated in 247 fetuses with isolated CDH. Logistic regression analysis was used to assess the prognostic value of the individual o/e MR-FLV for association with the need for postnatal patch repair. RESULTS: Seventy-seven percent (77%) of patients with a CDH (190/247) required prosthetic patch repair and the defect was closed primarily in 23% (57/247). Patients requiring a patch had a significantly lower o/e MR-FLV (27.7 ± 10.2%) than patients with primary repair (40.8 ± 13.8%, p < 0.001, AUC = 0.786). With an o/e MR-FLV of 20%, 92% of the patients required patch repair, compared to only 24% with an o/e MR-FLV of 60%. The need for a prosthetic patch was further influenced by the fetal liver position (herniation/no herniation) as determined by magnetic resonance imaging (MRI; p < 0.001). Fetal liver position, in addition to the o/e MR-FLV, improves prognostic accuracy (AUC = 0.827). CONCLUSION: Logistic regression analysis based on the o/e MR-FLV is useful for prenatal estimation of the prosthetic patch requirement in patients with a CDH. In addition to the o/e MR-FLV, the position of the liver as determined by fetal MRI helps improve prognostic accuracy. KEY POINTS: • The o/e MR-FLV is associated with the need for postnatal patch repair in CDH. • The need for a patch is associated with a significantly lower o/e MR-FLV (p < 0.001). • The patch requirement is also influenced by fetal liver position. • Fetal liver position, in addition to the o/e MR-FLV, improves prognostic accuracy. • CDH-fetuses with a high probability for patch requirement can be identified prenatally.

Repetitive MR measurements of lung volume in fetuses with congenital diaphragmatic hernia: individual development of pulmonary hypoplasia during pregnancy and calculation of weekly lung growth rates.

OBJECTIVE: To investigate individual changes in fetal lung volume (FLV) in fetuses with isolated congenital diaphragmatic hernia (CDH) and to calculate weekly growth rates of the FLV using serial MR examinations during pregnancy. METHODS: MR-FLV was measured in 89 fetuses with CDH. All fetuses received two MRIs. A mean weekly growth rate of the FLV was determined for each fetus and compared with the growth rate of healthy fetuses. RESULTS: Mean observed-to-expected MR-FLV (o/e MR-FLV) measured at the first MRI was 33.3 ± 12.2% and 29.5 ± 10.9% at the second MRI. In 61% of all fetuses (54/89) the o/e MR-FLV decreased during pregnancy, 26% (23/89) showed an increase in the o/e MR-FLV and 13 % (12/89) had stable values. First and last o/e MR-FLV values were significantly associated with mortality and neonatal extracorporeal membrane oxygenation (ECMO) requirement with a higher prognostic accuracy of MR-FLV measurements near delivery. Patients with CDH had lower weekly lung growth rates than healthy fetuses. There was a significant difference in the mean weekly growth rate between survivors and non-survivors and patients with and without ECMO requirement. CONCLUSION: Individual development of FLV in patients with CDH during pregnancy is extremely variable. Follow-up MR-FLV measurements are advisable before deciding upon pre- and postnatal therapeutic options. KEY POINTS: • Lung development in congenital diaphragmatic hernia (CDH) during pregnancy is extremely variable. • MRI demonstrates that lung growth rate is reduced in fetuses with CDH. • The final observed-to-expected fetal lung volume provides the best prognostic information. • Follow-up measurements are advisable before deciding upon therapeutic options.

MRI-based ratio of fetal lung volume to fetal body volume as a new prognostic marker in congenital diaphragmatic hernia.

OBJECTIVE: The objective of our study was to evaluate the prognostic accuracy of the MRI-based ratio of fetal lung volume (FLV) to fetal body volume (FBV) for predicting survival and the need for extracorporeal membrane oxygenation (ECMO) therapy in fetuses with congenital diaphragmatic hernia (CDH). MATERIALS AND METHODS: MRI was performed in 96 fetuses (34 females and 62 males; mean gestational age, 33 ± 5 [SD] weeks; range, 23-39 weeks) with CDH and 44 healthy control subjects. FLV and FBV were measured for each fetus by one of three investigators, and we calculated the FLV/FBV ratio. Additionally, a subgroup analysis of growth-restricted fetuses was performed. Logistic regression analysis was used to model the dependence of survival and ECMO requirement on the FLV/FBV ratio. Prognostic accuracy was evaluated by applying the area under the curve (AUC). RESULTS: Seventy-eight of the 96 (81%) fetuses survived and 35 (36%) neonates needed ECMO therapy. The FLV/FBV ratio was significantly higher in fetuses who survived (p < 0.0001; AUC = 0.829). Neonates who received ECMO therapy showed a significantly lower prenatal FLV/FBV ratio (p = 0.0001; AUC = 0.811) than neonates who did not need ECMO therapy. A subgroup analysis (n = 13) showed a trend toward a higher FLV/FBV ratio of survivors in comparison with nonsurvivors (p = 0.065; AUC = 0.875). CONCLUSION: In our study, the MRI-based FLV/FBV ratio was able to predict neonatal survival and ECMO requirement in children with CDH with high accuracy. Unlike other prognostic parameters, FLV/FBV ratio is independent of a reference to a control group and may enhance prognostic accuracy particularly in growth-restricted neonatal patients.

Multiple aseptic splenic abscesses in a 15 year old patient.

BACKGROUND: Splenic abscesses in children are rare. In recent years aseptic abscesses have been recognized as a new disease entity, especially in adults. CASE PRESENTATION: We present a rare case of a 15 year old girl with aseptic abscesses, in whom antibiotic therapy comprising metronidazole and meropenem was partly beneficial in improving the patient's clinical condition and inflammatory parameters. Eventually corticosteroid therapy led to complete and long lasting resolution of symptoms. Further diagnostic work-up revealed autoimmune thyroiditis, but no signs of inflammatory bowel disease. CONCLUSION: Aseptic splenic abscesses should always prompt clinicians to initiate further diagnostics to determine a potential underlying condition and a regular follow-up. Anaerobic bacteria may play a role in the pathogenesis of the disease and besides corticosteroid treatment antibiotics covering anaerobes may be beneficial.

Fetal lung volume in congenital diaphragmatic hernia: association of prenatal MR imaging findings with postnatal chronic lung disease.

PURPOSE: To assess whether chronic lung disease (CLD) in surviving infants with congenital diaphragmatic hernia (CDH) is associated with lung hypoplasia on the basis of the results of antenatal observed-to-expected fetal lung volume (FLV) ratio measurement at magnetic resonance (MR) imaging. MATERIALS AND METHODS: The study received approval from the institutional review board, with waiver of informed consent for this retrospective review from patients who had previously given informed consent for prospective studies. The ratio of observed to expected FLV at MR imaging was calculated in 172 fetuses with CDH. At postpartum day 28, the need for supplemental oxygen implicated the diagnosis of CLD. At day 56, patients with CLD were assigned to one of three groups-those with mild, moderate, or severe CLD-according to their demand for oxygen. Logistic regression analysis was used to assess the prognostic value of the individual observed-to-expected FLV ratio for association with postnatal development of CLD. RESULTS: Children with CLD were found to have significantly smaller observed-to-expected FLV ratios at MR imaging than infants without CLD (P < .001). Grading of CLD revealed significant differences in observed-to-expected FLV ratio between patients with mild CLD and those with moderate (P = .012) or severe (P = .007) CLD. For an observed-to-expected FLV ratio of 5%, 99% of patients with CDH developed CLD, compared with less than 5% of fetuses with an observed-to-expected FLV ratio of 50%. Perinatally, development and grade of CLD were further influenced by the need for extracorporeal membrane oxygenation (ECMO) (P < .001) and gestational age at delivery (P = .009). CONCLUSION: Manifestation of CLD in surviving infants with CDH is associated with the prenatally determined observed-to-expected FLV ratio. Early neonatal therapeutic decisions can additionally be based on this ratio. Perinatally, ECMO requirement and gestational age at delivery are useful in further improving the estimated probability of CLD.

Periodic MRI lung volume assessment in fetuses with congenital diaphragmatic hernia: prediction of survival, need for ECMO, and development of chronic lung disease.

OBJECTIVE: The purpose of the study was to investigate the ability to predict survival, need for extracorporeal membrane oxygenation (ECMO), and incidence of chronic lung disease in patients with congenital diaphragmatic hernia in the context of a classification into three different times of gestation (< 28, 28-32, and > 32 weeks) by assessing the ratio between observed and expected MRI fetal lung volume. MATERIALS AND METHODS: The data analysis included 226 fetuses with congenital diaphragmatic hernia. MRI was performed at different times of gestation with a T2-weighted HASTE sequence. Receiver operating characteristic curve analysis was performed to investigate the prognostic value of assessment of the ratio between observed and expected MRI fetal lung volumes at different stages of fetal growth. RESULTS: For all reviewed times of gestation, the ratio between observed and expected MRI fetal lung volumes had almost equivalent statistically significant differences for neonatal survival (p ≤ 0.0029), need for ECMO therapy (p ≤ 0.0195), and development of chronic lung disease (p ≤ 0.0064). Results with high prognostic accuracy for early and for medium and late times in gestation also were obtained. Receiver operating characteristic analysis showed the highest area under the curve (≥ 0.819) for neonatal survival. CONCLUSION: In patients with congenital diaphragmatic hernia, the relation between observed and expected MRI fetal lung volume is a valuable prognostic parameter for predicting neonatal mortality, morbidity represented by the development of chronic lung disease, and the need for ECMO therapy in early gestation (< 28 weeks) as well as later gestation with no statistically significant differences.

Prediction of mortality and the need for neonatal extracorporeal membrane oxygenation therapy by 3-dimensional sonography and magnetic resonance imaging in fetuses with congenital diaphragmatic hernias.

OBJECTIVES: To compare different rotation angles for assessment of fetal lung volume by 3-dimensional (3D) sonography with magnetic resonance imaging (MRI) regarding prediction of mortality and the need for neonatal extracorporeal membrane oxygenation (ECMO) therapy in fetuses with congenital diaphragmatic hernias. METHODS: One hundred patients with fetal congenital diaphragmatic hernias between 22 and 39 weeks' gestation were examined by 3D sonography and MRI. Sonographic contralateral fetal lung volumes were assessed by the rotational technique (virtual organ computer-aided analysis) at 3 different rotation angles: 6°, 15°, and 30°. The MRI fetal lung volumes were calculated based on multiplanar T2-weighted MRI. To eliminate the influence of gestational age, the observed to expected contralateral fetal lung volume on sonography and the observed to expected fetal lung volume on MRI were calculated. Receiver operating characteristic (ROC) curves were calculated for the statistical prediction of survival and need for ECMO therapy by the observed to expected contralateral fetal lung volume (sonography) and observed to expected fetal lung volume (MRI). RESULTS: One hundred cases were assessed for survival and 89 for ECMO necessity (11 neonates were not eligible for ECMO). For prediction of postpartum survival and ECMO necessity, the areas under the ROC curves (AUCs) showed very similar results for MRI and 3D sonography: observed to expected fetal lung volume by MRI, 0.819 (95% confidence interval, 0.730-0.909) and 0.835 (0.748-0.922), respectively; 6° sonography, 0.765 (0.647-0.883) and 0.820 (0.734-0.905); 15° sonography, 0.784 (0.672-0.896) and 0.811 (0.719-0.903); and 30° sonography, 0.732 (0.609-0.855) and 0.772 (0.671-0.872). Comparisons between the AUCs revealed no statistical differences. CONCLUSIONS: We have shown the good prognostic value of 3D sonography in fetuses with congenital diaphragmatic hernias compared with MRI, particularly when using small rotation angles. Therefore, it can be an appropriate diagnostic tool when counseling patients for congenital diaphragmatic hernias.

Right- versus left-sided congenital diaphragmatic hernia: postnatal outcome at a specialized tertiary care center.

OBJECTIVE: To systematically investigate the impact of the location of the defect in congenital diaphragmatic hernia on neonatal mortality and morbidity with a special focus on survival at discharge, extracorporeal membrane oxygenation requirement, and the development of chronic lung disease. DESIGN: Retrospective tertiary care center study with a matched-pair analysis of all fetuses that were treated for congenital diaphragmatic hernia between 2004 and 2009. SETTING: A specialized tertiary care center for fetuses with congenital diaphragmatic hernia. PATIENTS: Complete sets of data were available for 106 patients with congenital diaphragmatic hernia. For 17 of 18 infants with right-sided congenital diaphragmatic hernia we were able to allocate infants with left-sided congenital diaphragmatic hernia with no relevant difference in previously described prognostic factors, such as pulmonary hypoplasia and liver herniation. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: There was a strong trend toward better survival in infants with right-sided congenital diaphragmatic hernia than with left-sided congenital diaphragmatic hernia (94% vs. 70%; p = .07). More neonates with left-sided congenital diaphragmatic hernia died of severe pulmonary hypertension despite extracorporeal membrane oxygenation. Fewer neonates with right-sided congenital diaphragmatic hernia died, yet higher degrees of pulmonary hypoplasia and oxygen requirement were observed despite extracorporeal membrane oxygenation. CONCLUSIONS: In congenital diaphragmatic hernia, the location of the defect has a substantial impact on postnatal survival and the development of chronic lung disease. In left-sided congenital diaphragmatic hernia, pulmonary hypertension resistant to therapeutic management, including extracorporeal membrane oxygenation, is more common and is associated with a higher rate of neonatal demise. Right-sided congenital diaphragmatic hernia infants have an increased benefit from extracorporeal membrane oxygenation but the better survival entails a higher rate of chronic lung disease.

Influence of different rotation angles in assessment of lung volumes by 3-dimensional sonography in comparison to magnetic resonance imaging in healthy fetuses.

OBJECTIVES: Three-dimensional (3D) sonographic volumetry is established in gynecology and obstetrics. Assessment of the fetal lung volume by magnetic resonance imaging (MRI) in congenital diaphragmatic hernias has become a routine examination. In vitro studies have shown a good correlation between 3D sonographic measurements and MRI. The aim of this study was to compare the lung volumes of healthy fetuses assessed by 3D sonography to MRI measurements and to investigate the impact of different rotation angles. METHODS: A total of 126 fetuses between 20 and 40 weeks' gestation were measured by 3D sonography, and 27 of them were also assessed by MRI. The sonographic volumes were calculated by the rotational technique (virtual organ computer-aided analysis) with rotation angles of 6° and 30°. To evaluate the accuracy of 3D sonographic volumetry, percentage error and absolute percentage error values were calculated using MRI volumes as reference points. Formulas to calculate total, right, and left fetal lung volumes according to gestational age and biometric parameters were derived by stepwise regression analysis. RESULTS: Three-dimensional sonographic volumetry showed a high correlation compared to MRI (6° angle, R(2) = 0.971; 30° angle, R(2) = 0.917) with no systematic error for the 6° angle. Moreover, using the 6° rotation angle, the median absolute percentage error was significantly lower compared to the 30° angle (P < .001). The new formulas to calculate total lung volume in healthy fetuses only included gestational age and no biometric parameters (R(2) = 0.853). CONCLUSIONS: Three-dimensional sonographic volumetry of lung volumes in healthy fetuses showed a good correlation with MRI. We recommend using an angle of 6° because it assessed the lung volume more accurately. The specifically designed equations help estimate lung volumes in healthy fetuses.

Congenital diaphragmatic hernia: predictive value of MRI relative lung-to-head ratio compared with MRI fetal lung volume and sonographic lung-to-head ratio.

OBJECTIVE: The purpose of this study was to evaluate the prognostic accuracy of a new MRI-based relative lung-to-head ratio in regard to neonatal survival and need for extracorporeal membrane oxygenation (ECMO) in the care of fetuses with congenital diaphragmatic hernia (CDH) and to compare it with the previously described sonographic relative lung-to-head ratio and relative fetal lung volume assessed at antenatal MRI. MATERIALS AND METHODS: Sonographic lung-to-head ratio and MRI fetal lung volume were measured in 90 fetuses (mean gestational age, 31.4+/-4.1 weeks) with CDH. Sonographic relative lung-to-head ratio and MRI relative fetal lung volume were assessed by expressing the observed sonographic lung-to-head ratio and MRI fetal lung volume as a percentage of the expected parameter value. The new MRI relative lung-to-head ratio was assessed as a percentage of the expected MRI lung-to-head ratio based on MRI fetal lung volume and MRI head circumference measurements. Measurements for survival and ECMO requirement were determined with the area under the curve (AUC). Data were analyzed for left-sided defects, right-sided defects, and associated liver herniation. RESULTS: Among fetuses with left-sided CDH, all parameters were excellent in determining neonatal survival and need for ECMO therapy (p

Peripheral bolus-chase MR angiography: analysis of risk factors for nondiagnostic image quality of the calf vessels--a combined retrospective and prospective study.

OBJECTIVE: The objective of our study was to evaluate the influence of endogenous and exogenous risk factors on the rate of nondiagnostic examinations of the calves in peripheral bolus-chase MR angiography (MRA). SUBJECTS AND METHODS: Peripheral bolus-chase MRA runoff studies in 177 patients with peripheral arterial occlusive disease (PAOD) were retrospectively assessed with regard to the rate of nondiagnostic image quality due to substantial venous overlay in the calf arteries requiring repeated MRA examinations. Logistic regression was used to analyze the rate of nondiagnostic MRA examinations as a function of several endogenous and exogenous risk factors and of the stage of PAOD. To probe the retrospective data, 22 consecutive patients were prospectively included and underwent a standard peripheral MRA examination if the probability of a nondiagnostic examination was less than 50% based on the results of logistic regression; otherwise, a hybrid MRA examination was ordered. RESULTS: Nondiagnostic image quality of the calf arteries was found in 53 patients (30%). The incidence increased with each stage of PAOD up to 39% for stage IV. For each increase in the stage of PAOD, the probability of nondiagnostic image quality increased by a factor of 1.5561 (p = 0.0024). With an increasing number of risk factors, a significantly (p = 0.0074) higher rate of nondiagnostic images was found. CONCLUSION: Based on the retrospective statistical analysis of PAOD stages and risk factors, selected patients can be triaged to undergo a specific hybrid MRA technique and thus circumvent the occurrence of nondiagnostic images and the need for repeated MRA examinations.

Can dynamic MR imaging predict response in patients with rectal cancer undergoing cetuximab-based neoadjuvant chemoradiation?

BACKGROUND: The aim of this study was to evaluate therapy response in patients undergoing cetuximab-CapIri-based chemoradiation for rectal cancer using dynamic magnetic resonance imaging (dMRI). PATIENTS AND METHODS: The volumetric degree of tumor regression and contrast media perfusion were compared to the results of the histopathologic ypTN staging. 33 patients were examined using a 1.5-T scanner with repetitive 2D FLASH sequences after contrast media application. All patients were examined twice - before therapy and immediately before surgery. RESULTS: In all patients, the tumor volume decreased (mean 72 +/- 16%). In 25/33 patients, the slope of the contrast media enhancement curve decreased (mean 31 +/- 20%). In histopathologically proven downstaging after therapy, the decrease in slope was significantly higher than in the group without downstaging, and the decrease in slope was better for distinguishing between 'responder' and 'non-responder' than the decrease in volume. CONCLUSION: Using dMRI helps to identify responders undergoing cetuximab-based chemoradiation better than volume decrease alone.

MR lung volume in fetal congenital diaphragmatic hernia: logistic regression analysis--mortality and extracorporeal membrane oxygenation.

PURPOSE: To prospectively assess the results of logistic regression analysis that were based on magnetic resonance (MR) image fetal lung volume (FLV) measurements to predict survival and the corresponding need for extracorporeal membrane oxygenation (ECMO) therapy in fetuses with congenital diaphragmatic hernia (CDH) before and after 30 weeks gestation. MATERIALS AND METHODS: Written informed consent was obtained and the study was approved by the local research ethics committee. FLV was measured on MR images in 95 fetuses (52 female neonates, 43 male neonates) with CDH between 22 and 39 weeks gestation by using multiplanar T2-weighted half-Fourier acquired single-shot turbo spin-echo MR imaging. On the basis of logistic regression analysis results, mortality and the need for ECMO therapy were calculated for fetuses before and after 30 weeks gestation. RESULTS: Overall, higher FLV was associated with improved survival (P < .001) and decreasing probability of need for ECMO therapy (P = .008). Survival at discharge was 29.2% in neonates with an FLV of 5 mL, compared with 99.7% in neonates with an FLV of 25 mL. The corresponding need for ECMO therapy was 56.1% in fetuses with an FLV of 5 mL and 8.7% in fetuses with an FLV of 40 mL. Prognostic power was considerably lower before 30 weeks gestation. CONCLUSION: Beyond 30 weeks gestation, logistic regression analysis that is based on MR FLV measurements is useful to estimate neonatal survival rates and ECMO requirements. Prior to 30 weeks gestation, the method is not reliable and the FLV measurement should be repeated, particularly in fetuses with small lung volumes, before a decision is made about therapeutic options.

MR relative fetal lung volume in congenital diaphragmatic hernia: survival and need for extracorporeal membrane oxygenation.

PURPOSE: To retrospectively evaluate the accuracy of the absolute fetal lung volume (FLV) measured at magnetic resonance (MR) imaging and seven formulas for calculating relative FLV to predict neonatal survival and the need for extracorporeal membrane oxygenation (ECMO) in fetuses with congenital diaphragmatic hernia (CDH). MATERIALS AND METHODS: This retrospective study was approved by the research ethics committee, and informed consent was received from all mothers for previous prospective studies. In total, 68 fetuses with CDH were assessed by using MR image FLV measurement within 23-39 weeks gestation. The relative FLV was expressed as a percentage of the predicted lung volume calculated with biometric parameters according to seven formulas previously described in the literature. Applying the area under the curve (AUC), the various relative FLVs and the absolute FLV were investigated for their prognostic accuracy to predict neonatal survival and the need for ECMO therapy. RESULTS: All relative FLVs and the absolute FLV revealed a significant difference in mean lung volume between neonates who survived and neonates who did not survive (P = .001 to P < .001) and measurement accuracy was excellent for each method (AUC, 0.800-0.900). For predicting neonatal ECMO requirement, differences in FLVs were smaller but still significant (P = .05 to <.009) and measurement accuracy was acceptable throughout (AUC, 0.653-0.739). CONCLUSION: The various relative FLVs and the absolute FLV measured at MR planimetry are each highly valuable in predicting survival in fetuses with CDH. For predicting whether neonatal ECMO therapy is required, the accuracy of the absolute FLV (AUC, 0.68) and that of the relative FLVs (AUC, 0.653-0.739) was acceptable.

Reliability and validity of MR image lung volume measurement in fetuses with congenital diaphragmatic hernia and in vitro lung models.

PURPOSE: To prospectively assess the reliability of magnetic resonance (MR) image volume measurement in fetuses with congenital diaphragmatic hernia (CDH) and the reliability and validity of measurements in in vitro lung models. MATERIALS AND METHODS: This study was approved by the ethics committee, and informed consent was obtained. MR fetal lung volume (FLV) was measured in 40 consecutive fetuses with CDH by using half-Fourier acquired single-shot turbo spin-echo MR imaging and true fast imaging with steady-state precession at 24-36 weeks gestation (mean gestational age, 30.6 weeks +/- 3.5 [standard deviation]). Lung volumes were independently assessed in three orthogonal section planes by two experienced observers. Additionally, 28 in vitro lung models of defined volumes of 1-60 mL were evaluated the same way. To assess measurement validity and reliability, the intraclass correlation coefficient (ICC) and the Bland-Altman plot were used. RESULTS: The interobserver reliability was high for both the lung models and FLV measurements (ICC, 0.999 and 0.928, respectively). Measurement validity was also good, with a mean difference between the calculated volume and the true volume of 0.4 mL (95% confidence interval: 0.30, 0.48). Measurement reliability and validity did not depend, to any considerable degree, on imaging plane or sequence (ICC range, 0.878-0.999) or on total volume. CONCLUSION: The reliability and validity of MR volume measurements are high. The method is independent of the sequence and the imaging plane and can be performed with a very good interobserver agreement, even in small volumes.

Extracorporeal membrane oxygenation in infants with congenital diaphragmatic hernia: follow-up MRI evaluating carotid artery reocclusion and neurologic outcome.

OBJECTIVE: The purpose of our study was to prospectively assess, using MRI and MR angiography, the cerebral and vascular status of 2-year-old children with congenital diaphragmatic hernia (CDH) in whom carotid artery reconstruction was performed after neonatal extra-corporeal membrane oxygenation (ECMO) therapy and to compare the neurologic development of children with vascular reocclusion with that of CDH children with successful repair and with non-ECMO controls. SUBJECTS AND METHODS: A total of 30 infants (17 boys, 13 girls; 2 +/- 0.26 years) were included. Of these, 18 (60%) infants received arteriovenous ECMO therapy with subsequent reconstruction of the right common carotid artery (RCCA). Two years postoperatively, the children were examined with cerebral MRI, including 3D time-of-flight and contrast-enhanced 3D MR angiography of the intra- and extracranial brain-supplying arteries. The pathologic findings were analyzed for the ability to predict impaired neurologic development. RESULTS: The RCCA was occluded or highly stenotic in 13 (72%) of 18 children. All infants showed intra- and extracranial collaterals and a patent internal carotid artery. The average duration of ECMO was not longer than in cases of successful reconstruction (p = 1). The ECMO group showed a significantly greater incidence of cerebral injuries (p = 0.007) but no relevant impairment in neurologic development compared with controls (p = 0.26). Unsuccessful RCCA repair had no predictive value for a poor neurologic outcome (p = 1). CONCLUSION: The outcome of RCCA repair after ECMO is possibly poorer than expected, with vascular occlusion or high-grade stenosis occurring in almost three quarters of patients. Although reocclusion of the RCCA does not increase the risk for cerebral lesions or an impaired neurologic development during the first 2 years postoperatively, the overall benefit of RCCA repair remains doubtful, and the potential long-term risk arising from these plaques has yet to be assessed.