NNS 2015 Abstract Book

PBBI. Increased microglial activation in neurogenic niches is sug-

gested to dampen the brain’s regenerative potential, and our future

studies will focus on investigating this effect.

Keywords: Microglia, Proliferation, PBBI

C8 Poster Session VI - Group C: Intracranial Pressure

C8-01

THE EFFECT OF OSMOTIC AGENTS ON CEREBRAL MI-

CROCIRCULATION AFTER TRAUMATIC BRAIN INJURY

Richard Rodgers

, Xinjia Han

, Xiaoming Jin

1,2

Indiana University School of Medicine, Department of Neurological

Surgery, Indianapolis, USA

Indiana University School of Medicine, Department of Anatomy and

Cell Biology, Indianapolis, USA

Introduction:

Mannitol and hypertonic saline (HTS) are commonly

used to treat suspected or documented intracranial hypertension in

moderate and severe traumatic brain injury (TBI). The effects of these

osmotic agents on altered cerebral blood flow that commonly ac-

companies TBI is not completely understood. The superiority of one

agent over the other is still up for debate. The purposes of this pilot

project were to 1) determine whether an intervention to affect cerebral

microcirculation could be assessed, 2) assess if mannitol and HTS

improve cerebral microcirculation, and 3) assess for a difference in

response between mannitol and HTS.

Methods:

Adult C57BL mice underwent craniotomy and window

placement for

in vivo

two photon imaging of cerebral blood vessels. A

fluorescent dye sulforhodamine 101 was injected intraperitoneally to

visualize blood vessels and circulating red blood cells (RBC). Mod-

erate TBI was induced using the controlled cortical impact (CCI)

method. Mice were randomized to a sham group, a CCI control group,

and two treatment groups that received a single intravenous injection

of 100

l of either 20% Mannitol or 3% HTS at 30 minutes post-

injury. Cerebral blood vessels in the peri-lesional regions were imaged

at baseline, and at 1, 3 and 5 hours post-injury. RBC velocities were

calculated based on line-scan and vessel diameters were measured

from time lapse images.

Results:

CCI caused dramatic decreases in both RBC velocity and

cerebral blood vessel diameter. Mannitol and hypertonic saline both

significantly increased RBC velocity and the diameters of cerebral

arterial, capillaries and veins.

Conclusion:

TBI results in abnormal cerebral microcirculation with

reduced blood flow in the peri-lesional cortical region. This pilot study

shows an intervention’s direct effect on blood flow to the injured brain

can be assessed, and that both mannitol and HTS improve peri-

lesional flow. Further experiments may delineate differences between

the two agents, and define a model for testing other potential inter-

vention strategies.

Keywords: Mannitol, Hypertonic Saline, in vivo two-photon im-

aging, microcirculation

C8-02

RAUMEDIC BOLT: INITIAL CLINICAL EXPERIENCE IN A

NEUROSURGICAL POPULATION

Rocco Armonda

, Daniel Felbaum, Kyle Mueller

MedStar-Washington Hospital Center/Georgetown University Hospi-

tal, Neurosurgery, Washington DC, USA

The utility of multi- modality monitoring to provide improved out-

comes in neurosurgical patients remains controversial. Regardless, the

ability to accurately measure intracranial pressure (ICP) and brain

tissue oxygenation can aid the clinician to tailor therapy to each in-

dividual’s physiology. We provide our initial experience using the

Raumedic Neurovent-P with zero-drift technology in a variety of

neurosurgical patients.

A retrospective analysis of 39 patients treated under the discretion

of the senior author (RAA) from February 2014 through February

2015 was performed. The mean age was 40 (range: 19–65). The av-

erage duration of monitoring was five days (range: 3–10 days). The

etiology for insertion of Raumedic Neurovent-P intraparenchymal

monitor was for traumatic brain injury (n

37) or aneurysmal sub-

arachnoid hemorrhage (n

2). Two patients underwent simultaneous

external ventricular drainage for concomitant hydrocephalus. Stable

patients routinely underwent immediate CT scan for evaluation of

monitor placement and potential complications. Antibiotics were

maintained until discontination of the monitor.

39 patients underwent single pass successful placement of the Neu-

rovent-P monitor in an anatomically appropriate location. No patients

required replacement of the monitor. There were no infections associ-

ated with monitor placement. There were 2 hemorrhages associated

with monitor placement that did not require further surgical interven-

tion. In several instances, the insertion of the monitor was associated

with pneumocephalus which resulted in aberrant brain tissue oxygen-

ation measurements. If the inaccurate recordings did not resolve over 4

hours, the team turned the monitor while in situ to aid in clearing the tip

of air or clot to resolve the issue. If it did not resolve, the cables were

replaced. Another error occurred when the clinician placing the monitor

did not push the catheter through the appropriate final locking mecha-

nism, which led to widely vacillating ICP or pbtO2 numbers. This was

resolved by using sterile technique to achieve the final locked position.

Insertion and set-up time takes approximately 15 minutes.

The implementation of Raumedic Neurovent-P monitor has allowed

for a safe and reliable placement of an intraparenchymal monitor.

Keywords: neuromonitoring, intraparenchymal monitor

C9 Poster Session VI - Group C: Neurotransmitter

C9-01

SEX HORMONE STATUS AND CONTROLLED CORTICAL

IMPACT AFFECT DOPAMINE NEUROTRANSMISSION AND

RESPONSE TO METHYLPHENIDATE ADMINISTRATION

Rashed Harun

1–3

, Elizabeth Brough

1,2

, Amy Wagner

1–3

Univ Pittsburgh, PhysicalMedicine/Rehabilitation, Pittsburgh, USA

Univ Pittsburgh, Safar Center, Pittsburgh, USA

Univ Pittsburgh, Neuroscience, Pittsburgh, USA

Dopaminergic (DAergic) agents are a mainstay of treating cognitive

and behavioral impairments following traumatic brain injury (TBI),

but little is known about how to personalize these treatments for

individuals. Sex hormones alter DA neurotransmission and the re-

sponses to DAergic agents. We investigated how sex, hormone status

and TBI affects DA neurotransmission and the physiological re-

sponses to the clinically utilized DA transporter (DAT) inhibitor

methylphenidate (MPH) using fast-scan cyclic voltammetry (FSCV).

We used 43 Sprague Dawley rats, separated into male, female, and

ovarectomized (OVX) groups that were either naı¨ve or injured using a

severe controlled cortical impact (CCI) over the right parietal lobe

(4 m/s, 2.9 mm deformation). We examined FSCV DA response am-

plitudes, and kinetic measures of DA release and maximal clearance

rate (Vmax) that relates to local functional DAT density. MPH

A-97