Endoscopic trans-nasal spontaneous CSF leak repair
Considerations
Etiology (Theories)
increased weight overall -> higher intraabdominal pressures -> decreases venous return to the heart -> increases cerebral blood volume/venous outflow -> prevents CSF absorption -> ICP
higher amts of adipose tissue -> higher amts of estrone -> leads to changes in CSF dynamics
Perhaps also need an additional arachnoid villi defect in cojunction with the above factors
Most common patient profile
77-90% of these cases are obese women
Most common anatomical location
Lateral recess of the sphenoid
Conservative management of BIH
ICP Management
>15cm H20 acetazolamide 500mg BID
>35 VPSMCC site
Imaging
Intrathecal fluoroscein
0.1mL 10% fluoroscein in 10mL injected into CSF over 10-15min (Kennedy)
Make sure CT and MRI are loaded onto the Medtronic Image Navigation System the day prior to surgery
MRIs with <50 slices are not as useful and may not need to be uploaded
2003: Endonasal endoscopic repair of spontaneous cerebrospinal fluid leaks
Preparation
Intrathecal fluorescein
Preparation to be done in sterile fashion
10% fluorescein order or 5% fluorescein (preferred)
dilute to 5% fluorescein, use sterile injectable NS
use the IV stop cock
then mix 0.5mL of 5% fluorescein solution in 10mL of CSF fluid
If 10% solution then only 0.25mL 10% solution needed to mix into 10mL of CSF fluid
inject into the CSF slowly over 5 minutes
prior to injecting, put sterile blue towel down at site of injection
sterile the injection cap with chlorhexidine
Remove cap with sterile gloves and set on sterile town
then inject in slowly to avoid risk of seizures
Prep and case should be done in sterile fashion
Instead of typical Liang draping where emitter left undraped
Regular use of splitter drape
Clear plastic drape over the emitter
Procedure
CSF Leak repair Liang style
Regular Jonathan prep, see FESS
Endoscopy
take a look around and see where fluoroscein is draining
Note: BIH pts tend to have multiple skull base defects
Perform regular FESS
once the sinus cell with the draining fluorescein is id’d, meticulous take down of sinus partitions around this cell.
Valsalva to ensure that this is the only cell that draining fluorescein.
Then take down the sinus cell of interest with meticulous dissection to make sure you see where the fluorescein is draining.
Dry up with 1/2x1/2 dry and 1:1000 epi pledgets.
Valsalva to confirm drainage from site of interest.
likely will see an encephalocele at site of skull base defect
Bipolar cautery of encephalocele (dont’ worry, this is non functional brain tissue)
Slowly bipolar and shrink down the encephalocele (which is usually mushroomed over the skull base defect)
This slow cautery and look will allow you to define the edges of the skull base defect
Small defects
fashion cartilage graft to plug the defect
when placing the graft, place somewhere nearby
then use seeker to prop into place
mucosa overlay graft (can get from septum, IT, MT)
dot the deep non mucosalized surface w marking pen
use a cups forceps and laydown somewhere nearby
then use seeker to prop it into place
duraseal
suction out the leftovers
Packing
Small Nasopore chunks over the duraseal.
lay down like we do for ear cases
Kennedy sponge in the middle meatus
cut the merocel string
size 6 green glove and use one of the fingers to cover the merocel entirely
silk stitch to stitch glove to merocel.
throw to air knots, one close to the merocel and one far away
tape string to cheek w steri-strip
Slow wakeup
+/- Lumbar drain pending Liang’s diva mood
Post-op
Lumbar drain
Titrate to 5-10 mL/hr output
Discharge medications
Antibiotics PO while pack is in place
Stool softener for 6 weeks (Dr. Liang - 2 weeks)
Diamox 500mg PO BID for 3 mo's
D/c instructions
Avoid valsalva
Breath in and out when changing positions
Light activity for 6 weeks (Dr. Liang - 2 weeks)
Other
Contact PCP for management of electrolytes