Endovascular Embolization of Chronic Subdural Hematomas After Surgery (ENCLOSURE)

Early eNdovascular Embolization for Chronic subduraL hematOma After SUrgery and Prevention of REcurrence (ENCLOSURE)

Chronic subdural hematomas (CSH) are one of the most frequent pathologies in emergency neurosurgical practice. Standard therapy for symptomatic CSH is surgical drainage. However, the recurrence rate after surgery is high (10 to 20% in the most of series, although it has been reported from 2 to 37%). Middle meningeal artery embolization (MMAE) is a promising minimally invasive procedure that has recently been proposed as an alternative or adjunctive treatment to surgery. The investigators hypothesize that early post operative endovascular treatment can reduce the recurrence rate in high-risk patients, improving neurological outcomes by reducing the need for reinterventions, hospitalizations, and post-operative complications. The aim of the investigators is to analyze the efficacy of and safety of early post-surgical embolization of MMA in reducing the risk of CSH recurrence.

The study was designed as an open-label, multicenter randomized trial involving patients with symptomatic CSH and surgical evacuation criteria. Patients will be randomized in a 1: 1 ratio to receive surgical drainage (the standard of care) or surgical drainage plus early endovascular embolization of MMA (< 72 hours after surgery). Endovascular procedures will be performed with non-adhesive embolizing fluids. The primary outcome will be the recurrence of CSH at 6 months and secondary outcomes will be the risk reduction of recurrence in patients with risk factors, functional status measured by the modified Rankin scale (range, 0 [no disability] to 6 [death]) at 6 months and complications related to endovascular procedure.

Surgery will consist of performing a craniotomy (burr hole or drill) and evacuation of the hematoma. Depending on the operator, the surgical procedure may incorporate the use of subdural space drainage devices (e.g. Jackson Pratt drainage) connected to a soft suction reservoir. If used, these devices should be removed within 48 hours of installation.

The endovascular procedure will be performed until 72 hours after surgical evacuation of chronic subdural hematoma. Embolization will be performed with non-adhesive embolizing fluids such as Onix®, Phil®, Squid® or Libro®.

Post surgical embolization of middle meningeal artery with liquid embolic agents (ethylene vinyl alcohol copolymers as Onix, Squid, Phil or Libro)

Liquid embolic agent: Onix (ethylene vinyl alcohol copolymer), Medtronic., Liquid embolic agent: Squid (ethylene vinyl alcohol copolymer), Balt., Liquid embolic agent: Phil (copolymer disolved in DMSO), Microvention-Terumo., Liquid embolic agent: Libro (ethylene vinyl aalcohol copolymer), Invamed.

The endovascular procedure will be performed until 72 hours after surgical evacuation of chronic subdural hematoma. Embolization will be performed with non-adhesive embolizing fluids such as Onix®, Phil®, Squid® or Libro®.

Defined ad reappearance of symptomatic blood collection or whose thickness is > 1 cm or which determines a deviation from the midline> 5 mm

Inclusion Criteria: Chronic subdural hematoma equal or greater than 10 mm, midline shift equal or greater than 5 mm or neurological symptoms attributable to mass effect. Recent diagnosis or recurrence Surgical treatment performed < 72 hours Informed consent signed by the patient or they responsible family member Exclusion Criteria: Advanced disease with life expectancy < 6 months Condition that contraindicated endovascular procedure: Pregnancy, renal failure defined as creatinine clearence < 30 ml/min, allergy to iodinated contrast. Unavailability for follow up st 6 months Patient expressly refuses treatment