Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where K. Wolfgang Neff is active.

Publication


Featured researches published by K. Wolfgang Neff.


American Journal of Roentgenology | 2009

Congenital Diaphragmatic Hernia: Predictive Value of MRI Relative Lung-to-Head Ratio Compared with MRI Fetal Lung Volume and Sonographic Lung-to-Head Ratio

A. Kristina Kilian; Thomas Schaible; Valeska Hofmann; Joachim Brade; K. Wolfgang Neff; Karen A. Büsing

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 <or= 0.0027). Prognostic accuracy was best for the newly devised MRI relative lung-to-head ratio (AUC, 0.816 and 0.807) and lowest for sonographic relative lung-to-head ratio (AUC 0.783 and 0.703). Among fetuses with right-sided defects, the predictive value was lower for all parameters (AUC, 0.788-0.560). All neonates without liver herniation survived. CONCLUSION Among fetuses with left-sided CDH, assessment of pulmonary hypoplasia based on MRI relative fetal lung volume and MRI relative lung-to-head ratio is excellent in prediction of neonatal survival and ECMO requirement. The prognostic accuracy is slightly better than that of sonographic relative lung-to-head ratio. Among fetuses with right-sided CDH, the prognostic value of all parameters is lower than those among fetuses with left-sided defects.


Radiology | 2008

MR Relative Fetal Lung Volume in Congenital Diaphragmatic Hernia: Survival and Need for Extracorporeal Membrane Oxygenation

Karen A. Büsing; A. Kristina Kilian; Thomas Schaible; Claudia Endler; Regine Schaffelder; K. Wolfgang Neff

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.


Radiology | 2008

MR Lung Volume in Fetal Congenital Diaphragmatic Hernia : Logistic Regression Analysis Mortality and Extracorporeal Membrane Oxygenation

Karen A. Büsing; A. Kristina Kilian; Thomas Schaible; Dietmar Dinter; K. Wolfgang Neff

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.


American Journal of Roentgenology | 2007

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

Karen Buesing; A. Kristina Kilian; Thomas Schaible; Steffan Loff; Sabrina Sumargo; K. Wolfgang Neff

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.


Pediatric Critical Care Medicine | 2012

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

Thomas Schaible; Thomas Kohl; Konrad Reinshagen; Joachim Brade; K. Wolfgang Neff; R. Stressig; Karen A. Büsing

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.


Onkologie | 2008

Preoperative Staging of Rectal Tumors : Comparison of Endorectal Ultrasound, Hydro-CT, and High-Resolution Endorectal MRI

Dietmar Dinter; Ralf-Dieter Hofheinz; Mark Hartel; Georg Kaehler; K. Wolfgang Neff; Steffen J. Diehl

Aim: The aim of this study was to compare transrectal ultra-sound (TRUS), hydro-computed tomography (hydro-CT), and endorectal magnetic resonance imaging (MRI) in the preoperative staging of rectal cancer. Patients and Methods: 23 patients with rectal adenocarcinoma underwent TRUS, hydro-CT, and MRI (1 Tesla) with endorectal coil. The results were correlated with the histopathological findings based on the TNM classification. Results: T staging with TRUS, hydro-CT, and endorectal MRI correlated with the histopa-thological findings in 83% of patients (19/23). Tumors were overestimated by TRUS in 2/23 patients, by CT in 3/23, and by MRI in 3/23 patients. Tumor size was underestimated by TRUS in 2 patients, by CT and MRI in 1 case each. Local lymphatic node involvement was correctly diagnosed with CT and MRI in 87% and 83%, respectively. Using TRUS, false-negative results in the staging of lymph node involvement were seen in 3/23 patients, whereas 1 patient was over-staged. Using hydro-CT as well as endorectal MRI, overstaging of the local lymph nodes took place in 2/23 patients. Conclusion: All methods are limited because peritumoral inflammation cannot be precisely distinguished from infiltration by the tumor. Correct lymph node staging is hampered in advanced disease using TRUS. In these patients, further cross-sectional imaging may be required.


Radiology | 2013

Fetal Lung Volume in Congenital Diaphragmatic Hernia: Association of Prenatal MR Imaging Findings with Postnatal Chronic Lung Disease

Angelika Debus; Claudia Hagelstein; A. Kristina Kilian; Christel Weiss; Stefan O. Schönberg; Thomas Schaible; K. Wolfgang Neff; Karen A. Büsing

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.


American Journal of Roentgenology | 2007

Bifid Tail of the Pancreas: Benign Bifurcation Anomaly

Dietmar Dinter; J.-Matthias Löhr; K. Wolfgang Neff

WEB This is a Web exclusive article. ifid tail of the pancreas (pancreas bifidum) is a rare developmental anatomic branching anomaly. Although most cases are detected incidentally, some patients may have peculiar clinical symptoms. We describe what are to the best of our knowledge the first documented findings of this condition on MRI and MR cholangiopancreatography (MRCP). Once diagnosed correctly, this benign anomaly does not require any specific therapy.


American Journal of Roentgenology | 2009

Peripheral Bolus-Chase MR Angiography: Analysis of Risk Factors for Nondiagnostic Image Quality of the Calf Vessels—A Combined Retrospective and Prospective Study

Dietmar Dinter; K. Wolfgang Neff; Giovanni Visciani; Ricarda Lachmann; Christel Weiss; Stefan O. Schoenberg; Henrik J. Michaely

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.


Scandinavian Journal of Gastroenterology | 2008

Endoscopy and magnetic resonance imaging in patients with Crohn's disease: A retrospective single-centre comparative study

Dietmar Dinter; Anja Chakraborty; Joachim Brade; Walter Back; K. Wolfgang Neff; Manfred V. Singer; Ulrich Böcker

Objective. There is ongoing debate about which imaging modality is best for patients with inflammatory bowel diseases. Magnetic resonance imaging (MRI) has been successfully used to evaluate the jejunum and the ileum. Because virtual colonoscopy by MRI requires bowel cleansing and/or rectal filling, endoscopy is preferred for assessment of the colon. However, hydro-MRI without special bowel preparation may be sufficient as a diagnostic tool if specifically targeted in the course of a known disease. The aim of this study was retrospectively to assess the correlation of endoscopy, histology and MRI findings for the terminal ileum and the colon in a cohort of patients with Crohns disease. Material andmethods. In all, 60 patients with a confirmed diagnosis of Crohns disease were included in the study. Here, 412 anatomical segments of the colon were analysed by MRI, 401 by endoscopy and 374 by histology. Results. Presence or absence of inflammation was concordantly diagnosed in 310 segments (77.3%). The highest concordance was found for the terminal ileum and, in patients with previous surgery, the anastomosis. Sensitivity and specificity for MRI versus endoscopy, MRI versus histology and endoscopy versus histology were 64.4%/81.1%, 62.1%/86.2% and 78.2%/80.3%, respectively. Conclusions. In a retrospective analysis of patients with Crohns disease, hydro-MRI assessment of inflammation in anatomical segments of the colon reaches acceptable concordance rates with endoscopy and histology without prior preparation of the bowel. The data justify a prospective controlled trial.

Collaboration


Dive into the K. Wolfgang Neff's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Sven Kehl

University of Erlangen-Nuremberg

View shared research outputs
Top Co-Authors

Avatar
Researchain Logo
Decentralizing Knowledge