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

High-Yield

Links

• Sinus videos: CSF leak repair of cribiform plate