{'fraction_non_alphanumeric': 0.03987915407854985, 'fraction_numerical': 0.03081570996978852, 'mean_word_length': 4.830985915492958, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
[Natural history of intramedullary cavernomas. Results of the French Multicentric Study].

INTRODUCTION
The prevalence of cerebral cavernomas is about 0.5% in the general population. In contrast, spinal cord cavernomas are considered as rare. The objective of this study was to determine the natural history of spinal cord cavernomas in a multicentric study.


METHODS
Clinical and neuroradiological findings were retrospectively collected. Diagnosis was based on pathological criteria or magnetic resonance (MR) findings.


RESULTS
Fifty-three patients were included (26 males, 27 females). Mean age at onset of symptoms was 40.2 years (range: 11-80). Initial symptoms were progressive (32) and acute myelopathy (20). One patient was asymptomatic. Clinical symptoms were related to spinal cord compression (24) and hematomyelia (19). Cavernoma location was dorsal (41) and cervical (12.). MR findings consisted of hyperintense signal on T1 and T2 sequences (19 cases), mixed hyperintense and hypointense signal (33 cases), and hypointense signal on T1 and T2 sequences in 1 case. Mean size was 16.3 mm (range: 3-54). Forty patients underwent surgical resection. Improvement was observed in 20 patients and worsening of neurological symptoms in 11. Length of follow up was 7.1 years. At the end of the study, 26 patients were autonomous, 18 handicapped and 1 bedridden.


CONCLUSION
This study provided precise data on the clinical and MR patterns of these lesions. The natural history is associated with a higher risk of hemorrhage recurrence, but is favorable in many operated patients. Microsurgery is the treatment of choice for most of these lesions.