Brain Injury Case Study

Fluid Percussion Brain Injury (FPI) Model – Miami:
Animals were anesthetized (70% N2O, 1-3% isoflurane, and 30% O2) 24 hr prior to injury and surgically prepared for parasagittal FPI as described previously.19 Briefly, a craniotomy (4.8 mm) was performed at 3.8 mm posterior to bregma and 2.5 mm lateral to midline. A plastic injury tube was placed over the exposed dura and affixed to the skull with adhesive and dental acrylic. The scalp was then sutured closed, and the animals were allowed to recover before returning to their home cage. After fasting overnight, the animals were anesthetized (70% N2O, 1-3% isoflurane, and 30% O2), intubated, and subjected to a pressure pulse of moderate (1.8 - 2.2 atm) intensity.20 Prior to the FPI, catheters
The trachea was intubated with a 14-gauge angiocatheter. Anesthesia was maintained using 2% isoflurane in 2:1 N2O/O2. Following intubation, rats were placed on a thermal blanket to regulate body temperature (37 °C) and the animals head placed in a stereotaxic frame. A parasagittal craniectomy (center of craniectomy at AP: +4.0 mm, L: +2.8 mm from lambda) 8 mm in diameter was performed to expose the brain to allow access for the impactor tip of the CCI device (Pittsburgh Precision Instruments, Inc.). CCI at a depth of 2.6 mm at 4 m/s was carried out as previously reported.20,21. After injury, the surgical area was closed by silk sutures and animal recovery was monitored by measuring tail pinch and righting reflexes. Sham animals underwent craniectomy only and no
PBBI surgery was performed as previously described.23 Anesthetized rats were placed on a thermal blanket to regulate body temperature (37 °C) and the animals head was secured in the stereotaxic device for insertion of the PBBI probe. After a midline scalp incision, a right frontal cranial window (diameter = 4 mm) was created using a dental drill to expose the right frontal pole (+4.5 mm AP, +2 mm ML to bregma). The PBBI probe was then advanced through the cranial window into the right hemisphere to a depth of 1.2 cm from the surface of the brain. Once the probe was in place, the pulse generator was activated by a computer to release a pressure pulse calibrated to produce a rapid expansion of the water-filled elastic tubing to induce an elliptical shaped balloon (diameter = 0.633 mm, duration = 40 ms) to a volume equal to 10% of the total brain volume. After deflation, the probe was manually retracted from the brain, the cranial opening was sealed with sterile bone wax and the skin incision closed with wound clips. Sham animals underwent craniectomy only with no insertion of the PBBI