Related Experiment Video
Updated: Aug 9, 2026
Role of Diffusion MRI Tractography in Endoscopic Endonasal Skull Base Surgery
Published on: July 5, 2021
Diffusion-weighted MR imaging abnormalities in pediatric patients with surgically-treated intracranial mass lesions
Justin S Smith1, Henry Lin, Mary Catherine Mayo
1Department of Neurological Surgery, Brain Tumor Research Center, San Francisco school of medicine, University of California, San Francisco, CA 94143-0112, USA. jsmith1enator@gmail.com
Introduction:
Diffusion-weighted imaging (DWI) is a magnetic resonance imaging (MRI) technique that measures the degree of water diffusion in vivo. DWI abnormalities are frequently observed on immediate postoperative imaging following surgical resection of gliomas in adults. These abnormalities subsequently demonstrate contrast enhancement, which may be confused with lesion recurrence. The purpose of this study was to investigate the occurrence of these postoperative abnormalities in pediatric patients with intracranial mass lesions.
Methods:
Thirty-three consecutive patients
Results:
The median patient age was 9.9 years (range 0.2-18 years). Supratentorial and infratentorial lesions were identified in 22 and 11 patients, respectively. Infiltrative and noninfiltrative, as well as benign and malignant lesions, were included. Postoperative imaging demonstrated areas of reduced diffusion adjacent to the resection cavity in 20 (61%) cases. The median volume of these areas was 1.7 cm3 (range 0.3 cm3-12.0 cm3). Subsequent imaging studies in 9 of the 18 cases showed contrast enhancement in the area corresponding to the DWI abnormality. There were no clinical deficits attributable to any of the diffusion abnormalities. There was no association between the occurrence of these abnormalities and whether the lesion was infiltrative, non-infiltrative, benign, or malignant.
Conclusions:
DWI abnormality on immediate postoperative MRI is common following surgery for newly diagnosed intracranial mass lesions in pediatric patients. Focal contrast enhancement in the postoperative period may be confused with recurrence for some lesions. Our study suggests that immediate postoperative DWI is useful in interpreting new areas of focal contrast enhancement on subsequent imaging in children who have had surgery for brain tumors.
Insights
Diffusion-weighted imaging (DWI) abnormalities are common after pediatric brain tumor surgery. These findings on immediate postoperative MRI can help differentiate true tumor recurrence from expected post-surgical changes.
Area of Science:
- Pediatric neuro-oncology
- Neuroradiology
- Magnetic Resonance Imaging (MRI)
Background:
- Diffusion-weighted imaging (DWI) measures water diffusion in vivo.
- Postoperative DWI abnormalities are common in adult glioma resection, potentially mimicking recurrence.
- The incidence in pediatric intracranial mass lesions is less understood.
Purpose of the Study:
- To investigate the occurrence and significance of postoperative DWI abnormalities in pediatric patients with intracranial mass lesions.
Main Methods:
- MRI including DWI was performed before and immediately after surgery in 33 pediatric patients (<18 years).
- Patients had newly diagnosed intracranial mass lesions of various types.
Main Results:
- 61% of patients showed postoperative DWI abnormalities near the resection cavity.
- Contrast enhancement was observed in 9 of 18 cases with DWI abnormalities.
- No clinical deficits were associated with these diffusion abnormalities.
Conclusions:
- Immediate postoperative DWI abnormalities are frequent in pediatric intracranial mass lesion surgery.
- These findings can aid in distinguishing post-surgical changes from tumor recurrence on follow-up imaging.
- Postoperative DWI is a valuable tool for interpreting subsequent contrast enhancement in pediatric neuro-oncology patients.
