The Prospective Study Of The Natural History And Long-term Clinical Outcome Of Intradural Spinal Vascular Malformations

OBJECTIVE:The study is aimed to review the natural history and long-term clinical outcome of intradural spinal vascular malformation and to discuss the effectivity and the security of current treatment strategy and the possibility of improving the anatomical cure rate of the disease safely.Research Methods:Two hundred and eight-three cases of indrudural spinal vascular malformations were included.The angioarchitecture,age at initial onset,clinical presentation at first onset,the pre-treatment process of symptoms,the pre-and the post-treatment spinal cord function were assessed.Results:The clinical presentation at first onset including two different categories: sudden onset(57%)and progressive neurological deficits(43%).Spontaneous recovery could rule in most of those who had the sudden onset(63.3%)and if the observation duration was over than 2 months,the proportion could increase to 77.4% and 82.4% for Nidustype lesions and Fistula-type lesions respectively.The re-aggravation after the recovery or a stable period occurred in 40 cases(39.2%)and 18 cases(30.0%)for Nidus-type and fistula-type and if the observation duration was over than 1 year,this rate could increase to 89.2% and 62.5% respectively.The progressive re-aggravation mostly occurred after 5 years since the first onset and the sudden re-aggravation mostly occurred within 2 months or after 5 years since the first onset.Most of Nidus-type lesions(100%)and Fistula-type lesions(90.6%)who initially had a progressive neurological deficit showed a progressive deteriorating trend before they received treatments.The anatomical cure rates of Nidus-type and Fistula-type were 27.0% and 58.9%,the pre-treatment mALS scores were 3.9±3.4 points and 4.3±3.4 points and the data decreased to 2.8±2.8 points and 2.5±2.5 points respectively.The re-aggravation rate of Nidus-type and Fistula-type who had a sudden onset decreased to 23.5% and 6.7% after received the treatments and the proportion were 47.4% and 15.6% for progressive neurological deficit cases.The further post-treatment aggravation occurred only in partial obliterated cases,there were 32 cases for Nidus-type which including 15 cases of progressive aggravation and 17 cases of sudden aggravation,the annual sudden aggravation rate after partial treatment was 2.96%/y,which was significantly lower than the rate in pre-treatment period(5.95%/y).And there were 10 further posttreatment aggravation cases in Fistula-type which including 6 cases of progressive aggravation and 4 cases of sudden aggravation,the annual sudden aggravation rate after partial teeatment was 1.46%/y,which was significantly lower than the rate in pretreatment period(5.76%/y).Forty-three complications were seen in 43 cases,including 30 Nidus-type cases and 13 Fistula-type cases.For Nidus-type lesions who received partial treatment,as the nidus obliteration rate was improved the complication rate was gradually increased.The angioarchitecture and clinical manifestation between Nidustype lesions who received hybrid and non-hybrid surgery were similar,however the anatomical cure rate for hybrid surgical cases was higher(63.6% V.S 42.2%)and their complication rates were similar(11.1% V.S 19.6%).The feeding structures in hybrid surgical Fistula-type lesions was complicated than non-hybrid surgical group,however the anatomical cure rate for them was similar(77.8% V.S 78.2%)and the complication rate was lower in hybrid surgical cases(11.1% V.S 19.6%).Conclusions:Patients presented with the sudden onset should avoid emergent surgical treatment but endovascular embolization for the risk points such as AN-like structure should be suggested.Patients presented with the progressive neurological deficits should receive an early invasive treatment.Current treatments strategies are safety and effective.For lesions with a complicated angioarchitecture,the complication risk may be increased as the lesion obliteration rate was obtained,however partial treatment could not totally eliminate the post-treatment aggravation risk.Hybrid surgery may improve the obliteration rate safely and significantly.