Article Figures & Data
Figures
- Fig 1.
Axial T2-weighted (left) and axial postgadolinium T1-weighted (right) images through the posterior fossa of patient 2, acquired 3.6 months after completion of PT, reveal prominent T2 prolongation and heterogeneous enhancement within the pons. This portion of the pons was in the high-dose volume of irradiation.
- Fig 2.
Axial FLAIR (A) and postgadolinium coronal T1-weighted (B) images for patient 6, obtained 4.2 months after completion of PT, demonstrate patchy hyperintensity (FLAIR) and focal irregular enhancement (arrows in B) within the pons. Diffusion-weighted (C) and apparent diffusion coefficient map (D) images reveal small areas of restricted diffusion in the areas of abnormal signal and enhancement. This portion of the pons was in the high-dose volume of irradiation. The abnormalities improved on an MR imaging study obtained 1.5 months later and were no longer visible 4 months after they first appeared (E and F).
- Fig 3.
Axial T2 (left) and axial postgadolinium T1-weighted (right) images through the level of the thalami for patient 4 demonstrate enlargement of the right thalamus with hyperintensity on the T2-weighted image without enhancement (arrows).
- Fig 4.
Reformatted axial postgadolinium T1-weighted magnetization-prepared rapid acquisition of gradient echo image through the posterior fossa of patient 8, coregistered to the proton therapy treatment plan, demonstrates 2 areas of enhancement within the pons (outlined in yellow) located within the high-dose volume of irradiation (orange wash).
Tables
Patient Sex Diagnosis Location Age at Diagnosis (yr) Age at Proton Therapy (yr) 1 F EP Fourth ventricle 1.7 2.2 2 M EP Fourth ventricle 1.9 2.4 3 F CPC Left lateral ventricle 1.2 2.6 4 F PNET Left parietal lobe 2.7 3.2 5 F MB Fourth ventricle 1 1.4 6 F EP Fourth ventricle 3 3.5 7 F AT/RT Posterior fossa 0.6 1 8 M EP Fourth ventricle 2.2 2.6 Median 1.8 2.5 Mean 1.8 2.4 Note:—EP indicates ependymoma; MB, medulloblastoma.
Time from Completion of Proton Therapy to First MRI with Changes (mo) Time from Appearance of Changes to Start of Resolution of Changes (mo) Location of Abnormal Signal/Enhancement Physical Examination Findings Patient 1 5.3 2.2 Brain stem, cerebellum, upper cervical spinal cord None 2 3.6 2.3 Brain stem Unilateral weakness 3 5.6 3 Cerebellum None 4 3.4 3.1 Right thalamus (no enhancement) Unilateral weakness 5 6.3 2.2 Brain stem None 6 4.2 1.5 Brain stem and cerebellum Unilateral weakness 7 3 Patient died of disease before follow-up Brain stem None 8 3.2 3.5 Brain stem Ataxia Median 3.9 2.3 (of 7 with follow-up MRI) Mean 4.3 2.5 (of 7 with follow-up MRI)
