Background: Mastoid cavity resulting from a canal-wall-down (CWD) mastoidectomy causes major morbidity in the form of chronic discharge and infection in addition to difficulty in the fitting of hearing aids and giddiness. To overcome these problems, mastoid obliteration is recommended in many cases of canal wall down Mastoidectomy where the size of the cavity may turn out to be large.
Methods: This study demonstrates the authors’ technique of the Rambo flap for mastoid cavity obliteration performed in over 120 cases of CWD mastoidectomies.
Conclusion: The Rambo flap is an effective method of mastoid cavity obliteration that limits the size of the final mastoid bowl in CWD mastoid surgeries minimizing revision rates.
The concept of obliteration of the mastoid cavity was first introduced by Mosher in 1911 to promote healing of a mastoidectomy defect . Mosher originally used a superiorly based post auricular soft tissue flap. Kisch described the use of a pedicled temporalis muscle flap that was further expanded on by Rambo [2,3]. Popper described the use of a periosteal flap used to line, rather than obliterate the mastoid cavity . Palva went on to describe a modification of Popper’s flap as a musculo periosteal flap to obliterate the mastoid bowl . Palva further added the use of bone chips and bone pate´ in combination with a musculo periosteal flap . In addition to bone pate´, other materials that have been described for mastoid obliteration include fat grafts, diced cartilage, fascia, bone chips, and ceramic materials such as hydroxyapatite [7-11].
The primary goal of surgical intervention for chronic ear disease is the development of a safe, dry, low-maintenance and hearing ear [12,13]. Exteriorization of attic, mastoid and middle ear with a CWD mastoidectomy has a high rate of success in achieving a safe and dry ear , but there is a need for continuous inspection of the cavity and a high incidence of moisture resulting in discharge , Persistent moisture, infection, and discharge may cause problems in as many as one-third of patients requiring revision surgery following CWD mastoidectomy , which may be attributed to mucosalized surfaces, persistent cell tracts, or poorly ventilated areas
opening into the mastoid bowl .Despite careful observation of best practices including mastoid saucerization, removal of the mastoid tip, lowering of the facial ridge, and creation of an adequate-size meatus , moisture may still persist in areas of the mastoid bowl leading to stasis of mucoid exudate, localized areas of infection, and underlying mucosal changes. Open mastoid procedures have been criticized for the unfavorable cosmetic appearance due to a large meatoplasty, the need for regular cleaning, as well as the increased incidence of discharge and recurrent infections [13,16]. These concerns have led some to primarily advocate the use of Canal-Wall-Up (or Intact Canal Wall) mastoidectomies  or propose the reconstruction of the ear canal-mastoid partition . or obliteration of the mastoid cavity [13,18-20].
Many techniques for mastoid obliteration have been described in the literature. Palva described a mentally based musculo periosteal flap in combination with the use of cortical bone chips and bone pate´ for mastoid obliteration [5,6]. Moffat and colleagues described the use of bone pate´ and a superiorly based temporalis mucoperiosteal flap for mastoid obliteration . Some authors even advocated the use of mastoid obliteration for canal wall-up mastoidectomy in an attempt to prevent retraction pockets and recurrent cholesteatoma [22,23]. Montandon and colleagues described the use of cartilage to block the aditus and an abdominal fat graft for the canal wall-up mastoidectomy cavity . Gantz and colleagues
described reconstruction of the posterior canal wall and
mastoid obliteration . Their technique consisted of removal
of the posterior bony canal wall with a micro sagittal saw. The
mastoid cavity is obliterated with bone pate´ and bone chips
followed by replacement of the posterior canal wall segment. An
anteriorly based musculoperiosteal Palva flap is used to cover
the obliterated mastoid cavity.
Some authors described the use of the Temporo Parietal
Fascial Flap (TPFF) based on the superficial temporal artery
for mastoid obliteration. East and colleagues and Cheney and
colleagues [25,26] described the successful use of this TPFF flap
for mastoid obliteration. It provides an excellent option when
standard pedicled muscle or periosteal flaps are not available as
in revision cases with scar tissue or in patients with previous
irradiation. There are numerous reports in the literature, of the
use of calcium phosphate ceramic granules and hydroxyapatite
for mastoid obliteration. Hartwein and colleagues described
the use of hydroxyapatite to obliterate the mastoid bowl while
reconstructing the posterior canal wall with autologous conchal
cartilage . Yung and colleagues in their series describe 34
cases of mastoid obliteration using hydroxyapatite granules
and an inferiorly based periosteal flap . Proponents of the
use of synthetic materials such as hydroxyapatite point out the
minimal resorption of these materials over time . Mahendran
and colleagues describe the use of hydroxyapatite cement for
mastoid obliteration . In their study, however, there was a
significant incidence of postoperative infection with 50% of the
patients requiring revision surgery and removal of the foreign
A post auricular incision 5 mm posterior to the post auricular
groove is made. A thorough canal-wall down mastoidectomy is
performed and saucerized, adequate lowering of the facial ridge
and clearance of all mucosa and squamous epithelium in all
the mastoid air cell systems is done. The temporalis muscle is
exposed. A postero-superiorly based temporalis muscle flap is
fashioned (Figure 1). The flap receives abundant blood supply
mainly from the posterior deep temporal artery which courses
upward and backward in the area of the muscle included in the
flap. The flap is now rotated into the mastoid cavity and hence
used to obliterate the cavity (Figure 2). The senior author has
performed over 950 mastoid surgical procedures which includes
about 360 canal-wall-down (CWD) mastoidectomies in a span of
25 years. He has used the Rambo Flap for obliteration of the cavity
in about one third (about 120) of the CWD mastoidectomies
where the final size of the cavities appeared too large and
necessitated obliteration to reduce the size. The temporalis
fascia is then placed over the flap and under the tympanic
membrane remnant. An adequate meatoplasty is performed to
facilitate good inspection of the thus reduced-size cavity.
In the modern era of ear surgeries, mastoid cavities due to
canal-wall-down mastoidectomy are obliterated using various
techniques and materials. In our experience, the Rambo Flap,
described as early as 1958, is an effective method to obliterate
the mastoid cavities in CWD mastoidectomies.