Learning Objectives:
Anatomically there are two separate layers in ear, first middle ear cleft comprising mastoid air cells, antrum, aditus, middle ear and Eustachian tube all lined by contiguous mucosa which secretes mucus and is drained finally to Nasopharynx. Second being Canal skin and Tympanic membrane epithelium which exfoliates epithelium and is exteriorised. After surgery if this natural cavities loose their anatomy, operated cavity will no longer be dry or healthy in long term.
After complete canal down mastoidectomy two types of mastoid cavities can be found - First -completely sclerosed – means there remains no visible mastoid cells at the floor-here a large and thin fascia is lined to cover all the cavity and it epithelises and Second - cellular cavity (it is always not possible to exenterate all the air cells or at least impractical) – in which after complete Mastoidectomy, there still remain some cells at the floor. If this cavity is lined by fascia or cavity filling is done, the remaining air cells will keep on secreting mucus and granulate and the cavity will no longer be dry. A new method of solving this problem is - Conchal cartilage which is harvested at the time of meatoplasty is thinned out and laid down in cavity with convexity upwards so that it creates a small cavity communicating to aditus and then to middle ear and large fascia is lined over it.
Out of 102 canal down mastoidectomies we found primary healed cavity in 64 which never had cavity problem, 33 cavities were showing minor granulations and were cured with Trichloroacetic acid,steroid packing or drops.3 came to be tubercular and 3 never became dry in 15 months follow up.
The benefit of this procedure is that the cartilage needed is already harvested by meatoplasty, time saving as no cartilage fixation is needed to create a separate wall, time saving, reduces the size of cavity, primary healing occurs as full cavity is lined by fascia and no raw bone is exposed.
