POINTERS ON SURGICAL TECHNIQUES
| SPONTANEOUS TRANSTEMPORAL CEREBROSPINAL FLUID (CSF) LEAK — John P. Leonetti, MD, Professor of
Otolaryngology/Head and Neck Surgery, Loyola University, Stritch School of Medicine, Chicago
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| Etiology: tegmen tympani often dehiscent (1 mm to 1 cm); variable degree of pneumatization occurs in mastoid and tegmen;
air cells in area of cranial fossa erode as brain pulsates, leaving sharp edge; brain continues to pulsate against edge,
causing leak of CSF; brain tissue plugs hole, resulting in intermittent leak and symptoms; leakage into eustachian tubes
uncommon (low-pressure leak insufficient to open tubes); CSF rhinorrhea rare; typical signs and symptoms include fluid
in middle ear and aural pressure or fullness
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| Spontaneous CSF leaks: no preceding trauma or congenital anomaly explains leak; speaker reviewed 51 cases (48 patients;
3 bilateral); signs and symptoms—all patients had aural fullness; 42 patients had hearing loss; tinnitus or pulsating
noise in ear (caused by brain pulsations) occurred in some patients; 2 patients had headache; 6 patients experienced
problems with balance; clear effusion noted in middle ear (but, difficult to see when middle ear completely filled); 18
patients had otorrhea, due to placement of PE tubes (unnecessary); 3 patients had rhinorrhea; 1 patient had perforation
and drainage; diagnosis—coronal CT diagnostic for tegmen defect; many patients have \>1 pinhole defect; coronal
magnetic resonance imaging (MRI) confirms, but not necessary for diagnosis
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| Surgical repair: gravity works against repairs made from below (increases risk for recurrence); bone grafting from below
problematic; middle fossa craniotomy—2-hr procedure; extradural elevation of temporal lobe results in minimal
risk for injury; pinholes sutured closed; carpet graft using fascia from temporalis repairs dural defect and covers missed
pinholes; bone graft repairs bony defect
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| Surgical pearls: external auditory canal best landmark for internal auditory canal; twisting 18-guage needle tipped with
methylene blue through scalp at level of external ear canal marks location on skull; C- or U-shaped scalp incision preferred
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| Postoperative care: patients stay in intermediate care unit for 2 to 4 days; patients instructed to avoid heavy lifting,
nose-blowing, exercise, airplane travel, and straining for 1 mo; standard follow-up at 1 mo, then every year for 5 yr;
complications—seroma; hematoma; delayed facial palsy (patient recovered with corticosteroid treatment); prolonged
headache
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| Long-term results: recurrences probably caused by missed pinhole; recurrence—in patients with good hearing, middle
fossa approach repeated to repair missed pinholes; approach through ear canal (obliteration of ear) preferred in patients
with profound sensorineural hearing loss or dead ears
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| Pearls: clear ear effusion easy to miss; other symptoms (aural fullness, pressure, pulsatile noise in ear) increase index of
suspicion; coronal CT diagnostic; ⓶-transferrin not indicated
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| ANTERIOR SKULL BASE TUMOR SURGERY — Larry Hoover, MD, Professor, Department of Otolaryngology/Head
and Neck Surgery, Kansas University Medical Center, Kansas City
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| Surgical team: neurosurgeon (long-standing relationship helpful); ophthalmologist (helps assess tumors that impact vision
and manages postoperative visual disturbances); skilled angiographers
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| Preoperative evaluation: physical examination—endoscopic examination identifies type of lesion (eg, benign polyps
soft with minimal vascularity, not fixed in place; hemangiopericytomas fixed, fibrous, and vascular) in most cases;
imaging—CT (primary imaging) shows bony involvement; intraoperative CT used for image guidance; MRI with contrast
provides additional information about invasion into soft tissue and vascularity; positive findings on positron emission
tomography (PET) indicate metabolically active tumor (increased risk for metastasis and recurrence); angiography;
other studies—ophthalmic examination
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| Tumor growth: in general, tumors expand in direction of least resistance; skull-base tumors can extend into sinuses;
debridement—powerful debriders allow easy removal of portions extending into sinuses or nasal cavities; but, removal
complicates assessment of tumor base and area needed for resection and limits utility of PET
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| Controlling bleeding: angiography team important, especially when removing vascular tumors endoscopically; embolization
helpful to minimize bleeding
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| Instrumentation: variety of angled telescopes and instruments help remove tumors from less accessible areas of skull base;
intraoperative image guidance important; debrider with bipolar cautery helps prevent bleeding and facilitates complete resection
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| Wound healing and recurrence: large cavities in skull base heal well (but look terrible initially); mucosa regenerates
easily, even after radiation therapy; rate of recurrence lower than expected, possibly due to hostile environment in sinuses
(ie, presence of bacteria and yeast may inhibit recurrence of microscopic disease)
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| Frontal sinus: options for removing tumors—obliteration of sphenoid or frontal sinus (but material used for obliteration
may obstruct view and limit ability to identify recurrent disease); wide opening of sinus and excision of frontal sinus
aids in postoperative observation
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 | Surgical pearls: repair of defect—retract pericranium (intact pericranium used to cover skull base defect and prevent
postoperative complications); stitch pericranium to dural defect, not to skull base (risk for pneumocephalus and CSF
leaks); cover pericranial flap with split-thickness skin graft (additional barrier); preventive measures—place nasal
trumpets just below soft palate (transmit pressure, caused by coughing, away from repaired area); resecting inverted
papillomas—avoid disrupting tissue planes and performing craniotomies (allow underlying virus to move into anterior
cranial fossa); resect endoscopically
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| Ethmoid sinus: open nasofrontal duct widely (prevents formation of postoperative mucoceles); consider placing stent for
4 to 5 days; suction area carefully to maintain frontal drainage; approach—endoscopic approach used to remove even
large tumors; subcranial approach through anterior skull base preferred by some surgeons; combined approach also used
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| Sphenoid sinus: tumors relatively rare, include adenoid cystic and pituitary tumors; extent of involvement (eg, cavernous
sinus, carotid arteries, optic nerve) difficult to assess; even aggressive tumors tend to push on bone, causing thinning
rather than invasion; palpation reveals presence of bone (not always visible on CT); tumors rarely invade lateral areas
(exceptions include some squamous cell carcinomas); surgical pearl—removing anterior wall aids in postoperative evaluation
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| MANAGING COMPLICATIONS OF MASTOID SURGERY — Clough Shelton, MD, FACS, Professor and Chief, Division
of Otolaryngology/Head and Neck Surgery, University of Utah, School of Medicine, Salt Lake City
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| Facial nerve injury: actively identifying location of nerve reduces likelihood of accidental injury and allows cautious
removal of disease; beginning with known landmarks helpful; technique—open antrum; find dural plate and follow medially
to lateral canal (to determine level and position of facial nerve); use adequate suction and irrigation while drilling
in direction of nerve; common sites of injury—tympanic portion (especially during stapes surgery and tympanoplasty);
external genu; disorientation—surgeon may become disoriented (eg, during exostosis surgery in patients with extensive
disease) and not realize position relative to facial nerve; anomalous facial nerve—uncommon reason for injuring facial
nerve, because presence of other abnormalities (eg, auricle, ossicles) generally alerts surgeon of impending problem; patients
with congenital conductive hearing loss—image patients before surgery to assess position of facial nerve (may
interfere with stapedectomy)
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| Intraoperative exposure of nerve: stop immediately; examine nerve under high power to assess damage to epineurium;
dictate notes about exposure and assessment in surgical report; consider removing small amount of bone from either
side of foramen to reduce compression in case of swelling (could cause delayed facial paralysis); treat with
postoperative corticosteroids, if necessary
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| Partial transection: extent of transection sometimes difficult to assess (labyrinth, ossicles, and intact canal walls may
obstruct view); conservative management—repair when transection <33% of diameter; bring together frayed ends and
seal with Avitene or Gelfoam; completely cut transections \>33% of diameter, then graft nerve
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| Complete transection: end-end repair—in chronic ears, remove nerve from fallopian canal and trim ends; to bridge
resulting gap, manipulate nerve over corner of stapes and take down canal wall; nerve graft ----- 2 anastomoses, but
technique may result in less tension on nerve; right auricular nerve good donor (matches diameter; located near operative
field; provides sufficient length with minimal neural deficit); no sutures necessary when fallopian canal intact (lay
graft in canal and cover with Avitene)
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| Nerve grafting technique: cut graft slightly longer than gap to ensure snug fit; handle graft with wet blade; trim epineurium
with fresh blade; bevel edge if diameters unequal; sutures—resulting reaction to foreign body disrupts axonal architecture,
therefore, minimize number of sutures; speaker prefers epineurial repair using small monofilament (eg, 8.0
or 9.0 proline) and cardiovascular needle (generally requires 2-3 sutures)
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| Postoperative injury to facial nerve: important to assess function in immediate postoperative period (young patients
may maintain facial tone despite injury; dressing may push eyebrow down and close eye); paralysis—facial nerve
monofascicular in region of mastoid; therefore, intratemporal injury results in general (not regional) paralysis; local anesthesia
may affect facial nerve, causing paralysis in immediate postoperative period (common after stapes surgery; patient
recovers within hours); packing of meatus (as in canal-wall down mastoidectomy) may put pressure on nerve; loosening
packing should reverse paralysis; unidentified intraoperative injury—if above issues not responsible for paralysis, consider
possibility of intraoperative injury to nerve
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| Medicolegal issues: discuss possibility of facial injury with patient and family before surgery; when repairing injury, involve
another otolaryngologist or otologist, when appropriate; repair nerve within 72 hr of injury to avoid accumulation
of granulation tissue
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| Treatment of postoperative paralysis: loosen packing, if appropriate; treat with corticosteroids; follow up
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| Labyrinthine trauma: diseased oval window—if stapedial tendon intact, dissect posterior to anterior to avoid subluxation
or dislocation of stapes; for patients with extensive disease, graft ear first, then perform stapedectomy in second
stage (after tympanic membrane [TM] healed) to remove remainder of disease without spreading infection; semicircular
canal—injury may occur by exposing fistula caused by cholesteatoma or by fenestrating canal with drill; conservative
management of fistulae important when infection present; options include exteriorizing disease by taking down canal
wall or trimming matrix closely with canal wall up, then removing matrix 6 mo later with sterile ear and intact TM; when
removing matrix from fistula, position trimmed fascia to cover fistula immediately (this should occur at end of surgery;
subsequent drilling may disrupt fascial covering); fascia also used to cover fenestration in labyrinth (position with wet instrument
to avoid sticking); if fascia not readily available, bone wax acceptable to seal hole (want water-tight seal, but
avoid filling labyrinth); postoperative dizziness likely
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| Vascular injury (sinus): drill may fenestrate anteriorly-positioned sigmoid sinus unexpectedly during mastoidectomy;
field fills with blood, but bleeding easily stopped (temporarily) with finger (alert anesthesiologist of blood loss; begin repair);
bone wax sufficient to repair small holes; thrombin Gelfoam or Surgicel good for repairing large exposures;
Gelfoam—place Gelfoam on injury and cover with cottonoid; use suction to desiccate Gelfoam through cottonoid; carefully
peel cottonoid away (avoid disturbing Gelfoam patch); intraluminal packing—if Gelfoam insufficient, pack with
Surgicel; pack inside and outside of sinus (dumbbell shape) to avoid embolization; if bone present, pack between bone
and sinus; enlarge small holes; use blunt-ended instrument to pack Surgicel through hole into sinus (do not pack lumen
completely); trim extraluminal tail and cover with bone wax to maintain in place
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| Jugular bulb: pack with Surgicel; leave extraluminal tail to prevent embolization; complications—as Surgicel expands,
packing may put pressure on lower cranial nerves, causing paralysis; alternative approach—open neck; tie off
vein; open mastoid; pack sinus; pack extraluminally (especially if repair requires large amount of packing)
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| Injuries to carotid artery: often occur when red vascular mass (aberrant carotid artery) in anterior quadrant of middle
ear mistaken for glomus tumor; middle ear mass—biopsy unnecessary; location of mass (revealed by imaging) identifies
mass (aberrant carotids located anteriorly; glomus tumors and jugular bulb dehiscences located in hypotympanum;
facial nerve neuroma usually located in posterior-inferior quadrant, hanging from facial nerve); packing—pack off eustachian
tube and ear canal to avoid filling with blood; consider intraluminal balloon occlusion; maintain blood pressure
carefully in postoperative period (hypotension may cause stroke)
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| CSF leaks: intraoperative—create water-tight seal with dumbbell-shaped muscle plug (intradural and extradural portions;
“bottle and cork” fit); check for leakage; postoperative—elevate head of bed; acetazolamide (eg, Diamox); repair
surgically if necessary (eg, when infection present)
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Educational Objectives
| The goal of this activity is to provide diagnostic and surgical pearls for the otolaryngologist. After hearing and assimilating
this program, the clinician will be better able to:
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| 1. Diagnose spontaneous leaks of cerebrospinal fluid.
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| 2. Discuss surgical options for removing tumors in the anterior skull base.
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| 3. Implement measures to improve healing after anterior skull base surgery.
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| 4. Identify and prevent common complications associated with mastoid surgery.
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| 5. Manage neural and vascular injuries that occur during mastoid surgery.
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Discussed on This Program
Acetazolamide [Dazamide, Diamox, Diamox Sequels]
Microfibrillar collagen hemostat [Avitene Hemostat, Hemopad, Hemotene]
Absorbable gelatin powder, sterile [Gelfoam]
Absorbable gelatin sponge [Gelfoam]
Oxidized cellulose [Oxycel, Surgicel]
Suggested Reading
Ajalloueyan M: Experience with surgical management of cholesteatomas. Arch Otolaryngol Head Neck Surg
132:931, 2006; Batra PS, Citardi MJ: Endoscopic management of sinonasal malignancy. Otolaryngol Clin North
Am 39:619, 2006; Dusick JR, et al: BioGlue ® for prevention of postoperative cerebrospinal fluid leaks in transsphenoidal
surgery: a case series. Surg Neurol 66:371, 2006; Evans AK, et al: Pediatric facial nerve paralysis: patients, management
and outcomes. Int J Pediatr Otorhinolaryngol 69:1521, 2005; Guntinas-Lichius O, et al: Postoperative
functional evaluation of different reanimation techniques for facial nerve repair. Am J Surg 191:61, 2006; Kabil MS,
Shahinian HK: Application of the supraorbital endoscopic approach to tumors of the anterior cranial base. J Craniofac
Surg 16:1070, 2005; Leonetti JP, et al: Spontaneous transtemporal CSF leakage: a study of 51 cases. Ear Nose Throat
J 84:700, 2005; Paleri V, Watson C: Objective assessment of the perineural vascular plexus as a landmark for the horizontal
part of the facial nerve in middle ear and mastoid surgery. Otol Neurotol 26:280, 2005; Prichard CN, et al:
Adult spontaneous CSF otorrhea: correlation with radiographic empty sella. Otolaryngol Head Neck Surg 134:767, 2006;
Renton JP, Wetmore SJ: Split-thickness skin grafting in postmastoidectomy revision and in lateral temporal bone resection.
Otolaryngol Head Neck Surg 135:387, 2006; Safdar A, et al: Delayed facial nerve palsy following tympano-
mastoid surgery: incidence, aetiology and prognosis. J Laryngol Otol 120:745, 2006; Snyderman CH, Kassam AB:
Endoscopic techniques for pathology of the anterior cranial fossa and ventral skull base. J Am Coll Surg 202:563, 2006;
Weber PC: Iatrogenic complications from chronic ear surgery. Otolaryngol Clin North Am 38:711, 2005.
Faculty Disclosure
In adherence with ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this program, the
faculty reported nothing to disclose.
Dr. Leonetti was recorded in Chicago at Scientific Programs 2005-2006, sponsored by the Chicago Laryngological and
Otological Society and held December 5, 2005; Dr. Hoover was recorded in Kansas City at Annual Clinical Conference,
sponsored by the Kansas City Society of Ophthalmology and Otolaryngology, and held January 6-7, 2006; Dr. Shelton was
recorded in Los Angeles at Clinical Frontiers in Otolaryngology, sponsored by the Research Study Club of Los Angeles
and held January 13-14, 2006. The Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in
the production of this program.
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