²³Na-MRI of recurrent glioblastoma multiforme after intraoperative radiotherapy: technical note.

INTRODUCTION: We report the first case of an intraoperative radiotherapy (IORT) in a patient with recurrent glioblastoma multiforme (GBM) who was followed up with a novel magnetic resonance imaging (MRI) method-(23)Na-MRI-in comparison to a standard contrast-enhanced (1)H-MRI and (18)F-FET-PET. METHODS: A 56-year-old female patient with diagnosed GBM in July 2012 underwent tumor resection, radiochemotherapy, and three cycles of chemotherapy. After a relapse, 6 months after the initial diagnosis, an IORT was recommended which was performed in March 2013 using the INTRABEAM system (Carl Zeiss Meditec AG, Germany) with a 3-cm applicator and a surface dose of 20 Gy. Early post-operative contrast-enhanced and 1-month follow-up (1)H-MRI and a (18)F-FET-PET were performed. In addition, an IRB-approved (23)Na-MRI was performed on a 3.0-T MR scanner (MAGNETOM TimTrio, Siemens Healthcare, Germany). RESULTS: After re-surgery and IORT in March 2013, only a faint contrast enhancement but considerable surrounding edema was visible at the medio-posterior resection margins. In April 2013, new and progressive contrast enhancement, edema, (23)Na content, and increased uptake in the (18)F-FET-PET were visible, indicating tumor recurrence. Increased sodium content within the area of contrast enhancement was found in the (23)Na-MRI, but also exceeding this area, very similar to the increased uptake depicted in the (18)F-FET-PET. The clearly delineable zone of edema in both examinations exhibits a lower (23)Na content compared to areas with suspected proliferating tumor tissue. CONCLUSION: (23)Na-MRI provided similar information in the suspicious area compared to (18)F-FET-PET, exceeding conventional (1)H-MRI. Still, (23)Na-MRI remains an investigational technique, which is worth to be further evaluated.

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.