Increase in fluoroscopic radiation dose in successive sessions of multistage Onyx embolization of brain arteriovenous malformations compared with the first session

Efficacy and safety of embolization for arteriovenous malformations of the basal ganglia and thalamus via the transarterial approach

Background

To evaluate the effectiveness and safety profile of transarterial embolization in the treatment of brain arteriovenous malformations (bAVMs) within the basal ganglia and thalamus.

Methods

A retrospective clinical study was performed on 22 patients with bAVMs localized within the basal ganglia and thalamus who were treated with transarterial embolization (December 2012 and January 2019) in our center. The bAVMs were embolized via the transarterial approach with Onyx or Glubran according to the anatomical structure. A detachable or undetachable microcatheter was used in the procedure according to the length of the feeding artery. The data of these patients were retrospectively analyzed.

Results

Among the 22 patients, 9 bAVMs were located in the basal ganglia and 13 were located in the thalamus. Twenty patients presented with hemorrhage (90.9%), leaving 2 patients (9.1%) who had no symptoms. According to the Spetzler-Martin grading classification, 13 bAVMs (59.1%) were grade 3, 7 (31.8%) were grade 4, and 2 (9.1%) were grade 5. Procedure-related complications occurred in only 1 patient (4.5%). No deaths related to the operation occurred. All patients achieved anatomic stabilization and no bleeding was observed in the follow-up.

Conclusions

Selective embolization via the transarterial approach is safe and effective for bAVMs originating within the basal ganglia and thalamus. Our results demonstrate a low rate of complications and an elevated degree of anatomical disruption in the endovascular treatment of bAVMs stemming from the basal ganglia and thalamus.

Feasibility of low-dose digital subtraction angiography protocols for the endovascular treatment of intracranial dural arteriovenous fistulas

BACKGROUND

Among neurointerventional procedures, the embolization of complex shunt lesions usually requires more radiation dose. We aimed to evaluate the procedural outcome and safety in using low-dose DSA protocols for intracranial dural arteriovenous fistula (AVF) embolization treatment.

METHODS

Between January 2014 and July 2018, 55 patients with dural AVFs who underwent endovascular treatment were included in the study. The low-dose group (n = 27) included from January 2016 used various low-dose DSA protocols made by modifying the thickness of the copper filter or the detector entrance dose. We compared radiation dose metrics, such as air-kerma, kerma-air product (KAP), and fluoroscopy time, as well as clinical and imaging outcomes with the conventional-dose group (n = 28) included before January 2016.

RESULTS

The total KAP was 40.1% lower in the low-dose group (87.9 vs. 146.7 Gy cm², p = 0.002). The average number of DSA runs (25.1 vs. 25.5, p = 0.86) and fluoroscopy times (77.4 vs. 69.7 min, p = 0.48) were similar between the groups. An immediate favorable occlusion rate (total or near total occlusion) was achieved in 41 (74.5%) patients. Ten patients (18.2%) underwent additional procedures due to residual (n = 6) and/or recurrent (n = 5) lesions. At a median of 10 months follow-up, 45 patients (86.5%) had achieved favorable occlusion. Treatment outcomes showed no significant between-group differences. There was one case (1.8%) of procedure-related complications in the low-dose group. All but one patient showed favorable clinical outcomes (modified Rankin score ≤ 2).

CONCLUSION

The low-dose protocols were feasible by showing significant radiation dose reduction and acceptable procedural outcome.

A combined single-stage procedure to treat brain AVM

Complete resection of brain arteriovenous malformation (AVM) is a surgical challenge, mainly due to risk of intraoperative rupture. The objective of this feasibility study was to analyze complete resection rate at 3 months and clinical outcome at 6 months after treatment of brain AVM by combined single-stage embolization and surgical resection. A retrospective observational study from July 2015 to February 2019 was conducted at the Department of Neurosurgery of Strasbourg University Hospital, France. Decision to treat was taken on the basis of history of AVM rupture, symptomatic AVM, or morphologic risk factors for rupture. Complete resection rate was assessed on postoperative cerebral subtraction angiography at 3 months and clinical outcome at 6 months was evaluated on the modified Rankin Scale (mRS). In the 16 patients treated for symptomatic brain AVM, the rate of complete resection was 75%, resection with residual shunt 18.7%, and incomplete resection with residual nidus 6.3%. Good clinical outcome (mRS=0 or 1) was achieved in 81.3% of patients at 6 months. The transfusion rate was 7.1%. There were procedural complications in 12.5% of patients but no intraoperative ruptures. This combined single-stage procedure allows extensive preoperative embolization of the AVM, facilitating surgical microdissection by identifying the dissection plane and perforating arteries and allowing the operator to work in close contact with the nidus without fear of intraoperative rupture.