A Multi-center, Early Feasibility Study of Using the Mechanical Tissue Resuscitation™ (MTR®) Therapy System for Removal of Excess Fluid in Subjects Who Have Had a Portion of Their Skull Removed to Expose the Dura/Brain and Require Drainage for Fluid Removal.

Inclusion Criteria: Phase 1: 1. Patient is willing and able to provide written informed consent or has an appointed legally authorized representative (LAR) who can provide consent on the patient's behalf. 2. The patient's age is ≥ 22 and ≤ 65 years. 3. The patient has a clinical need for a craniotomy, craniectomy, or cranioplasty and for which, as an integral part of their care, a Jackson Pratt (JP) drain or equivalent would be placed at the surgical site. 4. The surgical case is classified as 'clean'. Phase 2: 1. All Phase 1 criteria 2. Patient has been diagnosed with a mild-to-moderate TBI with a GCS of 9 or above and has two reactive pupils. Phase 3: 1. All Phase 1 criteria 2. Patient has suffered an acute, severe TBI with a GCS of 7-8 and has two reactive pupils. Exclusion Criteria: Phase 1: 1. Patient has suffered an acute, severe traumatic brain injury, defined as less than 7 days since injury with GCS of less than 13. 2. Patient is pregnant or lactating. 3. Patient's BMI \> 45 4. Patient is participating in another clinical investigation. 5. Patient's anticipated survival is \< 48 hours. 6. Patient is incarcerated at time of hospital admission. 7. Patient has a coincidental infection. 8. Patient has thrombocytopenia (platelet count \< 150,000/µL). 9. Patient has an International Normalized Ratio (INR) \> 1.5. 10. Patient is a known active opioid abuser at the time of surgery. 11. Patient is a known active alcohol abuser at the time of surgery. 12. Active bleeding at the site of surgery prior to placement of the device. Phases 2 and 3: 1\. Exclusion criteria 2-12 from Phase 1