Myringoplasty

UNDERLAY MYRINGOPLASTY

  • Patient put in reversed Trendelenberg position with a head ring, & tied to the table. Antiseptic dressing (with Betadine & spirit) & draping done. Betadine should not enter middle ear.
  • Post-aural region + 4 quadrants of EAC infiltrated. Wait for 10-15 minutes.
  • Microscopic examination done to confirm findings.
  • Post-aural incision made and deepened up to periosteum.
  • Soft tissue dissection done over temporalis fascia with fine scissors and Freer’s periosteal elevator to identify temporalis fascia.
  • Saline infiltration done below the fascia. A nick made on fascia with knife and the temporalis fascia harvested using fine scissors. The fascia is thinner as it gets higher, so harvest the fascia as high as possible. Handle the fascia with care and avoid pressing in the centre or pinching with forceps. Put the graft over a cup medicine and remove excess soft tissue or muscle fibre.
  • Fascia cut to proper size and oval shape with a sharp knife. Do not use scissors. Size of the fascia should be enough to cover the perforation and at least 3 mm area all around the perforation. Graft should not be too thick or too thin. It should be thick in the centre and thin towards the periphery. Avoid drying of graft.
  • Periosteum over mastoid incised parallel to posterior canal wall & elevated anteriorly.
  • Margin of the perforation freshened with sickle knife / pick and cupped forceps.
  • Circumferential incision made at bony cartilaginous junction on posterior canal wall with circular knife, beginning at 12 o’clock position then carried down till 6 o’clock position.
  • Lateral portion of the posterior canal wall retracted anteriorly with ribbon gauze or canal wall retractor.
  • Tympanomeatal flap (medial portion of the posterior canal wall) elevated along with the epithelium of posterior T.M. remnant with fine periosteal elevator / sickle knife and microsuction. Suction applied on instrument & not on flap to avoid tears. Avoid using cotton ball to prevent granuloma formation.
  • Posterior portion of annulus elevated at 8 o’clock (as this is inferior to the level of incudo-stapedial joint & chorda tympani nerve) with the help of sickle knife. Micro-elevator used to elevate the annulus inferiorly up to 6 o’clock & superiorly up to the neck of malleus. Chorda tympani identified and preserved.
  • Handle of malleus skeletonized.
  • Medial surface of tympanic membrane remnant made raw with circular knife. Avoid injury to eustachian tube orifice. Nitrous oxide discontinued 20 minutes before grafting (Cummings).
  • Fascial graft inserted under posterior annulus (bigger dimension in antero-posterior axis) so that the soft tissue / muscle surface of the graft faces the middle ear. This prevents granuloma formation. To prevent the edge of the graft from infolding during insertion, the graft is wrapped around a large piece of moist gelfoam and inserted in the EAC, with the graft facing towards the middle ear. Gelfoam is then removed.
  • Fascial graft along with posterior annulus retracted anteriorly and small pieces of wet gel foam placed in middle ear cavity. 1st gelfoam inserted in eustachian tube orifice. This prevents movement of the graft during immediate post-operative period.
  • Graft placed carefully under the handle of malleus & tympanic membrane remnant, taking care to evert the edge. If there is a large antero-superior perforation, graft may be put over the handle of malleus.

Tuck-through-tail method:

  • Used in large perforations with no anterior support. Incision made on anterior canal wall skin just lateral to the annulus. Annulus elevated & the pocket widened to allow the passage of a fine suction cannula. Graft modified to fashion a 1 mm wide tail attached to the anterior edge of the graft. Graft placed in middle ear with its rolled tail placed anteriorly near the eustachian tube orifice. Fine suction cannula introduced through the pocket in the anterior canal wall to suck the tail of the graft. Suction cannula withdrawn with the tail until the graft gets firmly placed under the anterior annulus. Excess of the tail cut off lateral to the annulus.
  • Tympanomeatal flap replaced taking care again to evert its edge to prevent canal wall cholesteatoma.
  • EAC packed with gelfoam pieces (anteriorly first) followed by antibiotic soaked ribbon gauze (or umbilical tape) to prevent stenosis. The ribbon gauze is packed loose to allow for gel foam to swell up later.
  • EAC opening closed with cotton ball. Post-aural incision closed in layers.
  • Mastoid dressing applied. Facial nerve tested.
  • Mastoid dressing removed after 24 hours. EAC pack is removed on 7-8th
  • The EAC is cleaned 3 weeks after operation.