Endovascular Treatment for Low-Grade (Spetzler-Martin I-II) Brain Arteriovenous Malformations.

BACKGROUND AND PURPOSE: Surgical resection is usually considered as the first-line curative strategy for low-grade (Spetzler-Martin grade I-II) brain arteriovenous malformations because it has a high cure rate and low complications. The role of endovascular treatment remains to be clarified in this indication, especially after A Randomized Trial of Unruptured Brain Arteriovenous Malformations. Our objective was to assess the safety and efficacy of first-line endovascular treatment in low-grade brain arteriovenous malformation management at our institution. MATERIALS AND METHODS: Patients with low-grade brain arteriovenous malformations treated primarily with embolization in our department between January 2005 and December 2015 were retrieved from our prospectively collected registry. The primary outcome was the brain arteriovenous malformation obliteration rate, and secondary outcomes were disability or death secondary to brain arteriovenous malformation embolization assessed through modification of the modified Rankin Scale. RESULTS: Two hundred twenty-four patients completed endovascular treatment during the study period and represent our study population. Complete exclusion of brain arteriovenous malformations was achieved in 205 patients (92%), including 62.1% of brain arteriovenous malformation exclusions after a single endovascular treatment session. One patient died of a hemorrhagic complication after endovascular treatment, leading to a mortality rate of 0.4%. Twelve patients (5%) kept a permanent neurologic deficit secondary to a complication of the endovascular treatment. An overall good outcome (mRS 0-2) was reported in 179 patients (80%). CONCLUSIONS: Endovascular treatment might be a suitable alternative to surgical resection for complete exclusion of selected low-grade brain arteriovenous malformations.

Intracranial Arteriovenous Shunting: Detection with Arterial Spin-Labeling and Susceptibility-Weighted Imaging Combined.

BACKGROUND AND PURPOSE: Arterial spin-labeling and susceptibility-weighted imaging are 2 MR imaging techniques that do not require gadolinium. The study aimed to assess the accuracy of arterial spin-labeling and SWI combined for detecting intracranial arteriovenous shunting in comparison with conventional MR imaging. MATERIALS AND METHODS: Ninety-two consecutive patients with a known (n = 24) or suspected arteriovenous shunting (n = 68) underwent digital subtraction angiography and brain MR imaging, including arterial spin-labeling/SWI and conventional angiographic MR imaging (3D TOF, 4D time-resolved, and 3D contrast-enhanced MRA). Arterial spin-labeling/SWI and conventional MR imaging were reviewed separately in a randomized order by 2 blinded radiologists who judged the presence or absence of arteriovenous shunting. The accuracy of arterial spin-labeling/SWI for the detection of arteriovenous shunting was calculated by using the area under receiver operating curve with DSA as reference standard. κ coefficients were computed to determine interobserver and intermodality agreement. RESULTS: Of the 92 patients, DSA showed arteriovenous shunting in 63 (arteriovenous malformation in 53 and dural arteriovenous fistula in 10). Interobserver agreement was excellent (κ =0.83-0.95). In 5 patients, arterial spin-labeling/SWI correctly detected arteriovenous shunting, while the conventional angiographic MR imaging did not. Compared with conventional MR imaging, arterial spin-labeling/SWI was significantly more sensitive (0.98 versus 0.90, P = .04) and equally specific (0.97) and showed significantly higher agreement with DSA (κ = 0.95 versus 0.84, P = .01) and higher area under the receiver operating curve (0.97 versus 0.93, P = .02). CONCLUSIONS: Our study showed that the combined use of arterial spin-labeling and SWI may be an alternative to contrast-enhanced MRA for the detection of intracranial arteriovenous shunting.

Hemorrhagic complications after endovascular treatment of cerebral arteriovenous malformations.

BACKGROUND AND PURPOSE: Intracranial hemorrhage is the most severe complication of brain arteriovenous malformation treatment. We report our rate of hemorrhagic complications after endovascular treatment and analyze the clinical significance and potential mechanisms, with emphasis on cases of delayed hemorrhage after uneventful embolization. MATERIALS AND METHODS: During a 10-year period, 846 embolization procedures were performed in 408 patients with brain AVMs. Any cases of hemorrhagic complications were identified and divided into those related or unrelated to a periprocedural arterial tear (during catheter navigation or catheter retrieval). We analyzed the following variables: sex, age, hemorrhagic presentation, Spetzler-Martin grade, size of the AVM, number of embolized pedicles, microcatheter used, type and volume of liquid embolic agent injected, and the presence of a premature venous occlusion. Univariate and multivariate multiple regression analyses were performed to identify risk factors for hemorrhagic complications. RESULTS: A hemorrhagic complication occurred in 92 (11%) procedures. Forty-four (48%) complications were related to a periprocedural arterial perforation, and 48 (52%) were not. Hemorrhagic complications unrelated to an arterial perforation were located more commonly in the cerebral parenchyma, caused more neurologic deficits, and were associated with worse prognosis than those in the arterial perforation group. Only premature venous occlusion was identified as an independent predictor of hemorrhagic complication in the nonperforation group. Premature venous occlusion was significantly related to the ratio of Onyx volume to nidus diameter. CONCLUSIONS: Higher injected volume of embolic agent and deposition on the venous outflow before complete occlusion of the AVM may account for severe hemorrhagic complications.

Albendazole versus placebo in treatment of echinococcosis.

Echinococcus granulosus infection can have multiorgan involvement, and is common in Third-World countries. Uncontrolled studies show that albendazole can be effective in its treatment, but there are also reports of spontaneous resolutions. We therefore undertook a placebo-controlled double-blind parallel-group randomized study in Iran to evaluate the effect of albendazole on hydatid cysts. Twenty-nine patients with 240 cysts entered the study in 1994-95 and received either albendazole (400 mg twice a day, in 3 cycles of 6 weeks with 2 weeks between cycles) or placebo. At study completion, 172 and 31 cysts in the albendazole and placebo groups, respectively, were evaluable. In the treatment arm, 134 cysts showed improvement or cure compared to 4 in the placebo group (P < 0.001). Eighteen (82%) of 22 patients in the treatment arm showed either cure (8 patients) or improvement (10 patients); in the placebo group only 1 (14%) of 7 showed spontaneous improvement but no cure. Some patients with liver cysts after treatment showed increasing heterogeneity and density suggestive of inactive cysts. Patients with larger cysts and those with pulmonary involvement were better responders. Age and gender had no effect on outcome. The observed results are encouraging, showing albendazole has good effect on hydatid cysts and should be offered to patients before surgical treatment is considered.

A placebo controlled study of albendazole in the treatment of pulmonary echinococcosis.

Infection with Echinococcus granulosus is endemic in Middle Eastern countries. Some patients are noted to undergo spontaneous resolution, but many require surgical removal with its associated risks. Although, there are studies showing favourable responses to medical treatment, there is no controlled study on the effect of albendazole. In this study, 20 patients with 179 E. granulosus cysts affecting the lungs were entered into a triple blind parallel randomized clinical trial comparing the effects of albendazole versus placebo. Fifteen patients (150 cysts) completed 6 months of treatment; four patients (26 cysts) were in the placebo group and 11 patients (124 cysts) in the treatment group receiving 800 mg albendazole daily in three cycles of 6 weeks with 2 weeks between cycles. Ten of 11 patients (91%) in the treatment group showed either cure (five patients) or improvement (five patients); in the placebo group, only one of four (25%) showed spontaneous improvement but no cure. In the treatment group, 88 of 124 cysts (71%) showed improvement compared to four of 26 (15.4%) in the placebo group (p=0.000). Complication from therapy was insignificant; one case had recurrent disease, which responded to further therapy. It is suggested that patients suffering from uncomplicated hydatid disease should be given a trial of albendazole before surgery is considered.