Repair of Cerebrospinal Fluid Leaks (Cranial)

Operative Planning

Equipment

Operating Room Set-up

Anesthetic Issues

Preoperative intravenous antibiotics 30 min prior to incision
Lumbar drain is inserted preoperatively
Management of intracranial pressure: hyperventilation to pCO₂ of 25 to 30 mm Hg, mannitol 0.5 to 1 g/kg intravenously starting at time of skin incision, propofol (if indicated)

Positioning

Planning of Incision and Shave

With electrical clippers, a strip shave is performed approximately 1 cm in width over the planned incision

Sterile Scrub, Prep, and Drape

Incision and Scalp Flap

Incision is infiltrated with lidocaine with epinephrine
Operative timeout with anesthesia and nursing is performed to confirm procedure
Incision is performed down through galea, sparing periosteum
Raney clips or bipolar cautery are used to control scalp bleeding
Scalp flap can usually be dissected free from temporalis muscle and reflected anteriorly without having to incise the temporalis fascia or muscle
Pericranial flap is carefully dissected, reflected anteriorly, and wrapped in a moist gauze

Craniotomy and Extradural approach

Depending on suspected location of CSF leak, a frontal or bifrontal craniotomy is performed.
The dura is carefully elevated from the skull base and examined for obvious defects.
Any defects are repaired by first circumferentially mobilizing the surrounding dura and then closing the defect primarily with 4–0 Nurolon reinforced with fibrin glue.
If a defect cannot be repaired primarily, muscle, fascia, or a free flap of pericranium may be used as graft material to close the defect.
Certain CSF fistulas (i.e, Middle cranial fossa) can be repaired by a primarily extradural approach (Fig. 68.1), while others will require intradural exploration

Intradural Exploration and Repair

The dura is opened and reflected anteriorly
CSF is removed from the lumbar drain in increments of 5 mL until adequate brain relaxation is obtained
The frontal poles are gently retracted posteriorly to expose the floor of anterior fossa
Any dural defects are visualized and repaired either intra- or extradurally
The dural repair is reinforced with muscle, fascia, or a free flap of pericranium along with fibrin glue
The dural incision is closed while the operative field is irrigated thoroughly to ensure adequate repair of all dural defects
The pericranial flap is then placed between the dural defects and the floor of the anterior cranial fossa
The pericranial flap is sutured to the dura with 4–0 Nurolon and the suture line is reinforced with fibrin glue

Cranialization of Frontal Sinus