PHIL™ Middle Meningeal Artery Embolization for First-Line Treatment of Chronic Subdural Hematoma IDE Trial

• PHIL™ (Precipitating Hydrophobic Injectable Liquid) (Device): Embolization of MMA with PHIL.
• Surgical evacuation (Procedure): Surgical evacuation of cSDH.

Primary outcomes

• Primary Safety Endpoint [90 days post procedure]: Incidence of mRS 0-2.
• Primary Effectiveness Endpoint [90 days post procedure]: Incidence of clinically indicated (as adjudicated by CEC) surgical evacuation of the target cSDH among subjects in the PHIL™ MMAE arm.

Secondary outcomes

• Death or major disabling stroke. [30-, 90-, and 180-days post-index procedure]
• The composite of: recurrent or residual chronic subdural hematoma on the target side measuring ≥ 10 mm; retreatment; or major disabling stroke, myocardial infarction, or death from neurologic causes. [180 days post procedure]
• Resolution of cSDH without retreatment. [90- and 180-days post procedure]
• Neurological death [90- and 180-days post procedure]
• Change in EQ-5D-5L from baseline [90- and 180-days post procedure]
• cSDH-related hospital re-admissions and re-admission days [90- and 180-days post procedure]
• Index hospitalization length of stay [post procedure]
• Neurological Events of Interest: minor stroke, major stroke, cSDH expansion, acute cSDH, mRS deterioration of 2 points or greater [90 days and 180 days post procedure]

Sex: All, ages: 22 Years to any

Inclusion Criteria:

* Age 22 years or older
* Diagnosis of chronic subdural hematoma
* Subject, or their legally authorized representative provides a signed and dated Informed Consent Form
* Pre-morbid mRS 0-1
* cSDH measures ≥ 10 mm in greatest thickness
* cSDH exerts mass effect upon the subjacent brain
* Imaging characteristics indicative of chronicity
* Negative urine pregnancy test for female subjects of child-bearing potential
* Subject is able and willing to comply with all study protocol requirements, including return to the investigational site for all follow-up visits
* Subject presents with one or more of the following neurological symptoms: headache/head pressure, cognitive decline, speech difficulty or aphasia, gait impairment or imbalance, focal neurological deficit (weakness, paresthesia or sensory deficit involving of one or more extremities or facial droop), and/or seizure

Exclusion Criteria:

* Prior ipsilateral craniotomy or burr hole evacuation of cSDH
* Prior embolization of either MMA
* Requires (in the opinion of the treating surgeon) full or mini-craniotomy at time of randomization
* Emergent subdural hematoma evacuation needed
* cSDH with a focal location
* cSDH developed due to underlying condition
* Life expectancy of <1 year
* Presents with an intracranial mass other than subdural hematoma
* Presents with a meningioma with mass effect and/or ≥1 cm or currently undergoing radiation therapy for carcinoma or sarcoma of the head or neck region
* Serum creatinine level > 3.0 mg/dL at time of enrollment and not on dialysis
* Life-threatening allergy to radiographic contrast (unless treatment for allergy is tolerated or can be managed medically)
* Currently enrolled in another investigational study protocol that could potentially confound the interpretation of the study endpoints/outcomes
* Known dangerous anatomic variations leading to increased procedural risk or unsafe access for MMAE
* Contraindicated for the use of PHIL™ liquid embolic system

• David Fiorella, Principal investigator, Stony Brook University