Intracranial Pressure Assessment - Animal Models of Acute Neurological Injuries: Injury and Mechanistic Assessments - page 625

3. Procedures

1. Remove the cover of the optic fi ber probe (diameter 0.42 mm,
Samba Sensors, Biopac Systems, Inc, Fig. 49.1c ).
2. To protect the optical probe from direct mechanical infl uence
by the enclosing brain tissue, the optic fi ber probe is inserted
into a 0.9-mm PTFE tube.

3.1. Preparation of
Samba ICP Transducer

3.2. Preparation
of Samba ICP Monitor
System

1. Connect the Samba transducer to the control unit. The trans-
ducer is factory calibrated. No further calibration is needed.
2. Turn on the control unit. Need 1-2 min to stabilize the inter-
nal circuitry temperature.
3. Set the “zero baseline” against ambient pressure.
4. Connect the control unit to computer or data collection
system.

1. Inject sodium pentobarbital (50 mg/kg, i.p.) to anesthetize
the Sprague-Dawley (SD) rats (250-300 g).
2. Apply ophthalmic ointment to both eyes.
3. Use a heating pad with feedback regulator to maintain body
temperature at 37°C.
4. Position the rat in a Kopf stereotactic frame.
5. Use a hair clipper to remove hair from the scalp and apply
Betadine to the exposed skin.
6. Make a 2-cm sagittal incision over the midline of the scalp.
7. Using cotton-tipped applicators, clear away the fascia to expose
the bregma, then position the Heiss retractor under the skin to
keep the area exposed.
8. Measure 1.5 mm laterally and 1 mm posterior to the bregma
and mark the area for the cranial burr hole.
9. Holding the Dremel drill with 1-mm drill bit vertically over
the mark, slowly drill through the cranium, stopping when the
pressure is no longer felt in order to avoid tearing the dura.
10. Pierce the dura with a 23-gauge needle.
11. Position the optical probe over the burr hole and insert the
probe 3.5 mm ventrally into the lateral ventricle.
12. Use biological glue to seal the burr hole, then pour dental cement
around the PTFE tube to secure the probe to the bone.
13. Start measuring the ICP and collect the data on the computer.

3.3. Step-By-Step
Procedures of ICP
Monitoring