Spontaneous intracerebral hemorrhage: a very late delayed effect of radiation therapy

Progressive Multiple Cavernous Angiomas after Radiotherapy in a Pediatric Patient with Medulloblastoma: A Case Report

BACKGROUND

We report a case of progressive multiple cavernous angiomas.

PATIENT AND METHOD

A 16-year-old boy presented with a 2-month history of headache and dizziness. Six years earlier, he underwent surgery for cerebellar medulloblastoma and subsequent chemoradiotherapy according to the M-051 protocol of the Korean Society of Pediatric Neuro-Oncology. Follow-up brain magnetic resonance imaging (MRI) revealed a tiny hemorrhage on the cerebellum 3 months after 23.4-Gy craniospinal and 32.4-Gy boost radiotherapy.

RESULT

The multiple hemorrhagic lesions had progressively developed on the whole brain without any symptoms for 6 years. On admission, MRI revealed a 1.5-cm enlarged mass with subacute hemorrhage on the right frontal area. The mass was totally removed and diagnosed as cavernous angioma. However, 5 months later, the patient complained of a headache. MRI revealed 1.4- and 0.7-cm enlarged masses on the left frontal and right temporal areas with internal hemorrhage, respectively. The left frontal mass was totally removed, and the histopathological finding was suggestive of cavernous angioma.

CONCLUSION

This case showed early-developed multiple hemorrhagic lesions after radiotherapy, which had been progressive and were associated with some symptomatic cavernous angiomas. Pediatric patients with brain radiotherapy should undergo radiological check-up to identify vascular lesions, especially symptomatic patients.

Brain radiation-related black dots on susceptibility-weighted imaging

Small blood vessel injury is a feature of post irradiation brain. Susceptibility weighted imaging (SWI) is a technique that exploits the magnetic properties of tissues, such as blood and iron content and is thus sensitive to hemorrhage as a marker of small vessel injury. Our purpose was to assess post irradiation brain findings using SWI. We evaluated 12 patients with follow-up MRI studies who underwent cranial irradiation for primary or metastatic tumors. From their clinical records, the latency interval, type of radiation, and total dose were established. The number and the distribution of "black dots" on SWI were analyzed. We also compared the findings on SWI with those seen on other MRI sequences. In all patients, black dots were clearly identified on SWI, while on conventional MRI (T2 and FLAIR) none were visible. Two patients with glial tumors received radiation with fields conforming to tumor beds, while all other patients received whole brain irradiation or craniospinal radiation. The total radiation doses ranged from 45-54 Gy. Latency interval between the time of irradiation and time of detection of the black dots was four to 60 months (mean, 31 months). In ten patients diffuse black dots were observed and in two patients these were located in the irradiated field. Black dots occurred in the cerebrum, cerebellum, and choroid plexuses. None of these dots showed enhancement. Follow-up in four patients showed that the numbers of these black dots had increased. Black dots were not present before radiation in any patient. Radiation-related black dots are an effect of cranial irradiation and may be related to small vessel damage. SWI is a sensitive technique for evaluation of these black dots.

Delayed cerebral vasculopathy following cranial radiation therapy for pediatric tumors

BACKGROUND

Radiation-induced cerebrovascular injury is a well-known phenomenon. We analyze reported cases of delayed radiation-induced cerebrovasculopathy that present as moyamoya syndrome and/or intracerebral hemorrhage and to statistically analyze the relationship between radiation dose and the interval period between radiation and the presentation of cerebrovasculopathy.

METHODS

Patients ages <21 years at the time of radiation were included in analysis. A review of previous publications yielded 77 cases of delayed radiation-induced cerebrovasculopathy consisting of 45 cases of moyamoya syndrome, 30 cases of intracerebral hemorrhage, and two cases of both.

RESULTS

The median age at radiation was 4.8 years, with a range of 0.5-20 years. Approximately, 75% of these patients received radiation at the age of <9 years. The median interval period for moyamoya cases was 3.3 years (range: 0.3-20; P < 0.001), whereas the median interval period from radiation to presentation for intracerebral hemorrhage cases was 7.5 years (range: 0.8-27). There was significant association between radiation dose and interval from radiation to moyamoya syndrome (P < 0.001), whereas for patients with intracerebral hemorrhage, the association was insignificant (P = 0.31).

CONCLUSIONS

Pediatric patients who presented with moyamoya generally presented earlier than those who presented with intracerebral hemorrhage, suggesting that moyamoya may be a factor that predisposes the patient to intracerebral hemorrhage. In patients who presented with moyamoya, there was a statistically significant correlation between increasing doses of radiation and shorter time from radiation to disease presentation.

Environmental factors and stroke: A selective review

Despite numerous prior stroke risk factor investigations, much remains unknown about the effect of environmental factor changes on stroke incidence and mortality rates. Yet these data might be important for defining a number of measures to prevent stroke and for developing a greater understanding of the origin and incidence trends of stroke in different regions and populations. In this paper we review the current state of knowledge about certain environmental stroke risk factors.

Detection of hemorrhagic hypointense foci in radiation injury region using susceptibility-weighted imaging

BACKGROUND

Susceptibility-weighted imaging (SWI), a novel, highly sensitive 3D gradient echo MR imaging technique, is used to detect hemorrhage.

PURPOSE

To evaluate SWI at 3.0T for detection and visualization of hemorrhage at radiation injury region after radiotherapy for brain glioma.

MATERIAL AND METHODS

In 16 patients who had radiation injury in the vicinity of the previously resected and irradiated high-grade brain glioma, SWI examinations were performed on a 3T MR scanner. The presence of intralesional hypointense foci on SWI was evaluated by two neuroradiologists. Frequency of these foci on SWI was assessed and the number of these foci was counted. Diagnosis of radiation injury was assigned by means of histopathology or follow-up MR image.

RESULTS

In all 16 cases with cerebral radiation injury, nine were verified by means of histopathologic examination, seven by follow-up image. While in one patient quality of SWI was poor, in all remaining patients diagnostic-quality SWI was obtained. The intralesional hypointense foci were detected in 12 of 15 patients. These hypointense foci were nodular, angular, or tubular regions of low signal intensity on SWI. The distribution of these foci was diffusive (n=5) or scattered (n=7). Number of these foci per cm(2) on SWI was 7.25 ± 3.67.

CONCLUSION

SWI is a novel and promising technique for evaluation of hemorrhage at radiation injury regions in the vicinity of the previously treated gliomas.

Recurrent delayed brain hemorrhage over years after irradiation and chemotherapy for astrocytoma

We report on an adult patient with a right frontal astrocytoma, classification WHO II, who suffered from radionecrosis 3.5 years after surgery and combined radio- and chemotherapy. Beginning 8 years after initial diagnosis, repeated episodes of bilateral cerebral hemorrhage and cavitation occurred. This case description emphasizes the possibility of repeated hemorrhage as a delayed reaction to brain irradiation and chemotherapy.

Acute hemorrhage in late radiation necrosis of the temporal lobe: report of five cases and review of the literature

Hemorrhage in late cerebral radiation necrosis is a rare complication after radiotherapy for intracranial and extracranial neoplasms. We report 5 cases of acute hemorrhage in late radiation necrosis of the temporal lobe following radiation therapy for nasopharyngeal carcinoma. In a review of the literature, the authors identified a total of 27 such cases. The interval period between the onset of hemorrhage and cranial irradiation is long (mean = 7.8 years). The most prominent histological feature was the proliferation of large, dilated and thin-walled new blood vessels in a background of gliosis and fibrinoid necrosis of vessels. Rupture of these thin-walled new blood vessels is the proposed mechanism of hemorrhage in this condition.

Etiology of stroke in children

Although the risk factors for stroke in children are numerous and differ greatly from the causes of stroke in adults, a thorough diagnostic evaluation can identify one or more risk factors in most patients. Cardiac disorders and hemoglobinopathy are the most common causes of ischemic infarction, whereas various congenital anomalies of the blood vessels or defects in coagulation or platelet function are often found in children with intraparenchymal hemorrhage. More than one risk factor is commonly identified, especially in children with dural venous thrombosis. Identification of the underlying risk factors for cerebrovascular disorders in children is important because many of the risk factors can be treated, reducing the risk of subsequent strokes.

Formation of intracerebral cavernous malformations after radiation treatment for central nervous system neoplasia in children

OBJECT

Radiation is a common treatment modality for pediatric brain tumors. The authors present a retrospective review of six children who developed cerebral cavernous malformations after they underwent radiation treatment for central nervous system (CNS) neoplasia and propose two possible models to explain the formation of cavernous malformations.

METHODS

Three boys, aged 13, 9, and 17 years, suffered intracerebral hemorrhages from cerebral cavernous malformations 87, 94, and 120 months, respectively, after they received whole-brain radiation therapy (WBRT) for acute lymphocytic leukemia. A 10-year-old girl and a 19-year-old man developed temporal lobe cavernous malformations 46 and 48 months, respectively, after they received radiation therapy for posterior fossa astrocytomas. A 12-year-old girl developed a temporal lobe cavernous malformation 45 months after WBRT was administered for a medulloblastoma. In all of these cases the cavernous malformation appeared in the irradiated field, was not known to be present prior to radiation therapy, and developed after a latency period following treatment. The incidence of cavernous malformations in these patients suggests that children who undergo radiation therapy of the brain may have an increased risk of hemorrhage.

CONCLUSIONS

Two possible models may explain the formation of cavernous malformations following brain radiation in these patients. First, the cavernous malformations may form de novo in response to the radiation. Second, the cavernous malformations may have been present, but radiographically occult, at the time of radiation therapy and may have hemorrhaged in response to the radiation. The authors conclude that cavernous malformations may develop after brain radiation and propose a possible mechanism for this formation.