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Published on: October 3, 2010
Evolution of cerebral microbleeds after cranial irradiation in medulloblastoma patients
Duangnapa Roongpiboonsopit1, Hugo J Kuijf1, Andreas Charidimou1
1From The Hemorrhagic Stroke Research Program (D.R., A.C., L.X., A.V., S.M.-R., A.V.), J. Philip Kistler Stroke Research Center, Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA; Department of Medicine (D.R.), Faculty of Medicine, Naresuan University, Phitsanulok, Thailand; Image Sciences Institute (H.J.K.), University Medical Center Utrecht, the Netherlands; Department of Radiation Oncology (H.A.S.), Massachusetts General Hospital, Boston; and Department of Neurology (C.M.G., J.D.), Division of Neuro-Oncology, Massachusetts General Hospital Cancer Center, and Center for Regenerative Medicine, Harvard Medical School, Boston.
Objective:
To characterize the temporal and spatial pattern of cerebral microbleeds (CMBs) after cranial irradiation in patients with medulloblastoma.
Methods:
We retrospectively identified patients with medulloblastoma treated with craniospinal irradiation at the Massachusetts General Hospital between 1999 and 2015. Longitudinal MRI including T2*-weighted gradient-recalled echo (GRE) sequences were reviewed, and the prevalence, spatial pattern, and risk factors associated with CMBs were characterized.
Results:
We identified a total of 27 patients; 5 patients were children (median age 6.3 years) and 22 patients were adults (median age 28.8 years). CMBs were found in 67% (18/27) of patients, who were followed for a median of 4.1 years. Patients with CMBs had longer GRE follow-up time compared to those without CMBs (4.9 vs 1.7 years, p = 0.035). The median latency of the appearance of CMBs was 2.79 years (interquartile range 1.76-4.26). The prevalence of CMBs increased with each year from time of radiation therapy, and the cumulative prevalence was highest in patients age <20 years (100% cumulative prevalence, vs 59% in adult patients treated at age ≥20 years). CMBs were mostly found in lobar distribution and predominately in bilateral occipital lobes. Patients using antithrombotic medications developed CMBs at a significantly higher rate (p = 0.041).
Conclusions:
Our data demonstrate a high prevalence of CMBs following cranial irradiation, progressively increasing with each year from time of radiation therapy.
Insights
Cerebral microbleeds (CMBs) are common after cranial irradiation for medulloblastoma, increasing yearly post-treatment. Younger patients and those on antithrombotics show higher CMB prevalence.
Area of Science:
- Neuroimaging
- Radiation Oncology
- Neuropathology
Background:
- Cranial irradiation is a standard treatment for medulloblastoma.
- Cerebral microbleeds (CMBs) are potential long-term complications of radiation therapy.
- Understanding the temporal and spatial patterns of CMBs is crucial for patient management.
Purpose of the Study:
- To characterize the temporal and spatial distribution of cerebral microbleeds (CMBs) following cranial irradiation in medulloblastoma patients.
- To identify risk factors associated with CMB development after cranial irradiation.
Main Methods:
- Retrospective review of 27 medulloblastoma patients treated with craniospinal irradiation (1999-2015).
- Longitudinal MRI including T2*-weighted gradient-recalled echo (GRE) sequences were analyzed.
- Prevalence, spatial pattern, and risk factors for CMBs were assessed.
Main Results:
- CMBs were detected in 67% of patients, with a median latency of 2.79 years post-irradiation.
- CMB prevalence increased annually after radiation therapy, with highest cumulative prevalence in patients <20 years old.
- CMBs were predominantly located in lobar and bilateral occipital regions; antithrombotic medication use was associated with higher CMB rates.
Conclusions:
- Cranial irradiation for medulloblastoma leads to a high prevalence of cerebral microbleeds (CMBs).
- The incidence of CMBs progressively increases with time since radiation therapy.
- Age and antithrombotic medication use are significant factors in CMB development.
