Surgical removal of intracranial arteriovenous malformation immediately after embolization according to the results of LYS grading scale

Objective To explore the efficacy of surgical removal of intracranial arteriovenous malformation (AVM) immediately after embolization according to the results of Lawton-Young supplementary grading scale (LYS). Methods We retrospectively analyzed the data of 9 patients with intracranial AVM admitted to Department of Neurosurgery, Shanghai Punan Hospital of Pudong New Area from June 2016 to December 2017, accounting for 10.6% of all AVM patients admitted during the same period (85 cases). Nine patients were assessed by LYS grading and a surgical plan was developed based on the results of the assessment. LYS scores were grade 4 in 2 cases, grade 5 in 3 cases, grade 6 in 3 cases and grade 7 in 1 case. All patients underwent surgical resection of AVM immediately after interventional embolization. Digital subtraction angiography (DSA) was performed for imaging evaluation and the clinical efficacy was evaluated based on the modified Rankin Scale (mRS) after operation. Results All malformations of the 9 patients were resected successfully. Seven cases underwent elective microsurgery following partial embolization, 1 case underwent immediate surgery after embolization because the drainage vein was clogged, and 1 case underwent immediate surgery due to bleeding after embolization. The postoperative complications occurred in 3 cases, including 1 patient with hemianopia and 2 patients with intracranial infection. All patients were followed up for 6-15 months(median time: 7 months), DSA results showed that all the malformations completely disappeared, the cure rate was 100%. The mRS score was 0-1 in 8 cases and 2 in 1 case. Conclusion According to preoperative risk assessment based on LYS grading, selective endovascular embolization combined with subsequent microsurgery could provide a new surgical treatment approach for intracranial AVM patients with a relatively high cure rate. Key words: Intracranial arteriovenous malformations; Embolization, therapeutic; Treatment outcome; Lawton-Young supplymentary grading; Craniotomy