Integrated PET/MRI for planning navigated biopsies in pediatric brain tumors.
BACKGROUND
An integrated PET/MRI scanner has been used in selected cases of pediatric brain tumor patients to obtain additional metabolic information about lesions for preoperative biopsy planning and navigation.


METHODS
Four patients, age 9-16 years, received PET/MRI scans employing [(11)C]methionine positron emission tomography (PET) and contrast-enhanced 3D-MR sequences for neuronavigation. PET and MR sequences have been matched for neurosurgical guidance. An infrared camera-based neuronavigation system was employed with co-registered MR and PET images fused to hybrid images for preoperative planning, stereotactic biopsy planning, and/or intraoperative guidance.


RESULTS
All patients showed hot spots of increased amino acid transport in PET and contrast-enhancing lesions in MRI. In three of the four patients, PET hot spots were congruent with contrast-enhancing areas in MRI. In two patients, frame-based stereotactic biopsies were taken from thalamo-mesencephalic lesions. One patient underwent second-look surgery for the suspicion of recurrent malignant glioma of the posterior fossa. One incidental frontal mass lesion was subtotally resected. No complications occurred. Hybrid imaging was helpful during the procedures to obtain representative histopathologic specimens and for surgical guidance during resection. Co-registered images did match with intraoperative landmarks, tumor borders, and histopathologic specimens.


CONCLUSIONS
The integrated PET/MRI scanner offers co-registered multimodal, high-resolution data for neuronavigation with reduced radiation exposure compared to PET/CT scans. One examination session provides all necessary data for neuronavigation and preoperative planning, avoiding additional anesthesia in the small patients. Hybrid multimodality imaging may improve safety and yield additional information when obtaining representative histopathologic specimens of brain tumors.
Department of Neurosurgery, Pediatric Neurosurgery, University Leipzig, Liebigstrasse 20, 04103, Leipzig, Germany, preuss@neurosurgeon.ch.
Matthias
M
Preuss
Peter
P
Werner
Henryk
H
Barthel
Ulf
U
Nestler
Holger
H
Christiansen
Franz Wolfgang
FW
Hirsch
Dominik
D
Fritzsch
Karl-Titus
KT
Hoffmann
Matthias K
MK
Bernhard
Osama
O
Sabri
D000293:Adolescent; D001706:Biopsy; D001932:Brain Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D002648:Child; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008279:Magnetic Resonance Imaging; D008297:Male; D049268:Positron-Emission Tomography