- Email: [email protected]
Mastoid Obliteration
Otolaryngol Clin N Am 39 (2006) 1129–1142
Mastoid Obliteration Ritvik P. Mehta, MDa,*, Jeffrey P. Harris, MD, PhDb a
Department of Otology and Laryngology, Massachusetts Eye and Ear Infirmary/Harvard Medical School, Boston, MA, USA b Division of Otolaryngology/Head and Neck Surgery, Department of Surgery, University of California San Diego School of Medicine, 200 W. Arbor Drive, San Diego, CA 92103, USA
The concept of mastoid obliteration was first introduced in 1911 by Mosher to promote healing of a mastoidectomy defect [1]. Over the course of this century, there have been numerous reports detailing a variety of techniques of obliterating the mastoid cavity. The vast majority of obliteration techniques consist of either local flaps (muscle, periosteum, or fascia) or free grafts (bone, cartilage, hydroxyapatite, and so on) (Box 1). Mosher’s original description was that of a superiorly based postauricular soft tissue flap. Kisch described the use of a pedicled temporalis muscle flap that was expanded on by Rambo [2,3]. Popper [4] described the use of a periosteal flap used to line, rather than obliterate, the mastoid cavity. Palva [5] went on to describe a modification of Popper’s flap as a musculoperiosteal flap to obliterate the mastoid bowl. Palva [6] further added the use of bone chips and bone pate´ in combination with a musculoperiosteal flap. In addition to bone pate´, other materials that have been described as implants for mastoid obliteration include fat grafts, diced cartilage, fascia, bone chips, and ceramic materials such as hydroxyapatite [7–11].
Indications and contraindications The most common indication for mastoid obliteration is following canal wall-down tympanomastoidectomy for chronic otitis media. A canal walldown mastoid cavity, if not obliterated, can result in persistent otorrhea that can be difficult to control even with topical antibiotic therapy and frequent cleaning of the cavity. Other problems associated with a mastoid
* Corresponding author. E-mail address: [email protected] (J.P. Harris). 0030-6665/06/$ - see front matter Ó 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.otc.2006.08.007
oto.theclinics.com
1130
MEHTA & HARRIS
Box 1. Techniques of mastoid obliteration Local flaps Meatally based musculoperiosteal flap (Palva flap) Inferiorly based periosteal-pericranial flap Superiorly based musculoperiosteal flap Temporalis muscle flap Temporoparietal fascial flap (TPFF) Free grafts Bone chips/bone pate´ Fat Cartilage Fascia Hydroxyapatite
cavity may include the need for frequent cleaning, difficulty with the use of a hearing aid, water intolerance due to a susceptibility to infection, and propensity to vertigo by a caloric stimulus such as warm/cold air or water [12]. Obliteration of the mastoid bowl is indicated to reduce the size of the cavity. It is ideally conducted as a primary procedure at the time of canal walldown mastoidectomy. However, for a problematic mastoid bowl with chronic otorrhea and nonhealing, mastoid obliteration can be performed as a secondary revision procedure. Total tympanomastoid obliteration, or obliteration of the entire mastoid, middle ear, and Eustachian tube, is used for the prevention as well as management of cerebrospinal fluid leaks emanating through the temporal bone. The most common complication following microsurgery for acoustic neuroma is cerebrospinal fluid leak at a rate of 10.9% according to a recent metaanalysis [13]. Tympanomastoid obliteration can be performed primarily when the translabyrinthine approach is used for acoustic neuroma resection. Alternatively, it is used as a means of surgical treatment of cerebrospinal fluid (CSF) leak that has failed to heal with conservative measures such as bed rest, head elevation, and lumbar drainage. Tympanomastoid obliteration can be used for other causes of CSF leak as well such as meningoencephaloceles with CSF otorrhea or rhinorrhea or severe temporal bone trauma. Another indication for tympanomastoid obliteration includes reconstruction following surgical treatment for malignancies of the temporal bone. The defect created by lateral, subtotal, or total temporal bone resection typically requires obliteration of the middle ear, Eustachian tube, and mastoidectomy defect. This is especially important if there is a concomitant CSF leak resulting from the malignancy or the resection. Large defects may require the use of pedicled flaps or free tissue transfer for reconstruction [14].
MASTOID OBLITERATION
1131
A special situation that may require tympanomastoid obliteration is cochlear implantation in patients with a history of chronic otitis media. This group of patients can be challenging because of the risks associated with foreign body implantation in a potentially infected space. Tympanomastoid obliteration has been used in this setting to provide complete eradication of infection and inflammation as well as to provide a protective soft tissue layer over the electrode array [15]. It can also be used in patients with labyrinthitis ossificans in whom a drill-out of the cochlea is required with removal of the posterior canal wall and tympanic membrane [16]. Tympanomastoid obliteration can be performed in cases of chronic otitis media in patients with no usable hearing. It is important that complete eradication of disease is achieved by the surgeon before tympanomastoid obliteration [3,17]. Box 2 lists the most common indications for mastoid and tympanomastoid obliteration. Relative contraindications to mastoid obliteration include persistent active disease (cholesteatoma, malignancy, or active infection) within the tympanomastoid cavity. An exception to this is an extensive malignancy that may require tympanomastoid obliteration following subtotal resection in preparation for radiation therapy.
Techniques Mastoid obliteration following chronic ear surgery As mentioned above, a vast array of techniques have been described for mastoid obliteration following canal wall-down mastoidectomy for chronic otitis media. The authors prefer the Massachusetts Eye and Ear Infirmary technique of mastoid obliteration using a combination of bone pate´ and an inferiorly based periosteal-pericranial flap [17,18]. This technique is
Box 2. Indications for mastoid/tympanomastoid obliteration Canal wall-down mastoidectomy Chronic otorrhea/nonhealing of mastoid bowl Translabyrinthine acoustic neuroma resection CSF leak Extensive temporal bone trauma Temporal bone resection for malignancy Cochlear implantation in patients with chronic otitis media Cochlear implantation requiring extensive drill-out with removal of posterior canal wall Treatment of chronic otitis media in ears with no useful hearing
1132
MEHTA & HARRIS
outlined in detail. A postauricular incision 2- to 3-mm posterior to the postauricular crease is used (Fig. 1). Fig. 2 illustrates the site of harvest of the flap. Superiorly, the plane of the temporalis fascia is identified. Inferiorly, the postauricular muscles are divided and the skin is elevated in a supraperiosteal plane both anteriorly as well as posteriorly (Fig. 3). The temporalis muscle is then separated from the underlying pericranium at the level of the temporal line. The muscle is retracted superiorly to expose 3- to 4-cm of pericranium above the temporal line. The flap is then outlined with electrocautery. The width of the flap is approximately 2- to 3-cm, with the anterior limit being just posterior the external auditory canal. The pericranial portion of the flap consists of an extension 3- to 4-cm above the temporal line deep to the temporalis muscle. The flap is elevated inferiorly using a periosteal elevator and electrocautery for any dense adhesions (Fig. 4). It is left pedicled at the mastoid tip. A canal wall-down mastoidectomy is then performed for eradication of the disease process. At the beginning of the mastoidectomy, bone pate´ is collected from the lateral mastoid cortex using a Sheehy Pate´ Collector (OtoMed, Lake Havasu City, Arizona). The bone pate´ is kept moist and can be irrigated with antibiotic solution. At the end of the canal wall-down procedure, the bone pate´ is used to obliterate the mastoid cavity (Fig. 5). The inferiorly pedicled periosteal-pericranial flap is then used to cover the bone pate´ (Fig. 6). The pericranial extension of the flap allows coverage of the superior most aspect of the mastoidectomy defect. It is critical to completely cover the bone pate´ with the flap. Any exposed areas of bone are covered with split thickness skin grafts. The Koerner flap is replaced anterior to the obliterated mastoid cavity. Surgical pearls for success with this technique include the following: 1) A well-saucerized mastoid cavity with no ridges or cavities
Fig. 1. Typical postauricular incision used for mastoid obliteration. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
MASTOID OBLITERATION
1133
Fig. 2. Outline of the harvest site for the inferiorly based periosteal-pericranial flap. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
2) Adequate meatoplasty 3) Split thickness skin grafting to enhance reepithelialization 4) Complete coverage of bone pate with the periosteal-pericranial flap or fascia 5) Maximal lowering of facial ridge to level of facial nerve 6) Adequate canalplasty to remove anterior canal bulge 7) Drilling out the mastoid tip to allow the flap to smoothly lay into the mastoidectomy defect Although the aforementioned technique of mastoid obliteration is the workhorse at our institution, many other techniques of mastoid obliteration
Fig. 3. Coronal section of postauricular soft tissue and bone. The postauricular incision is kept lateral to the temporalis fascia and mastoid periosteum. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
1134
MEHTA & HARRIS
Fig. 4. The temporalis muscle is retracted superiorly. A periosteal elevator is used to elevate the flap from a superior to inferior direction. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
have been described. Palva’s original description describes a meatally based musculoperiosteal flap in conjunction with the use of cortical bone chips and bone pate´ for mastoid obliteration [5,6]. Fig. 7 illustrates the use of an anteriorly based musculoperiosteal flap. Moffat and colleagues [19] describe the use of bone pate´ and a superiorly based temporalis musculoperiosteal flap for mastoid obliteration. Some authors even advocate the use of mastoid obliteration for canal wall-up mastoidectomy in an attempt to prevent
Fig. 5. Bone pate´ is used to obliterate the mastoid; particular attention is paid to obliterate the sinodural, retrofacial, and mastoid tip areas. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
MASTOID OBLITERATION
1135
Fig. 6. The periosteal-pericranial flap is used to cover the bone pate´ and line the remainder of the cavity. The anterior aspect of the flap lies just over the facial ridge. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
Fig. 7. Schematic illustrating the use of an anteriorly based musculoperiosteal flap for obliteration of the mastoid cavity. (From Smyth GDL, Toner JG. Mastoidectomy: canal wall down techniques. In Brackman DE, Shelton C, Arriaga MA, editors. Otologic surgery. Philadelphia (PA): WB Saunders; 1994. p. 235; with permission.)
1136
MEHTA & HARRIS
retraction pockets and recurrent cholesteatoma [20,21]. Montandon and colleagues [20] use cartilage to block the aditus and an abdominal fat graft for the canal wall-up mastoidectomy cavity. Gantz and colleagues [22] describe a ‘‘canal wall reconstruction’’ tympanomastoidectomy with mastoid obliteration. Their technique consists of removal of the posterior bony canal wall with a microsagittal 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 describe the use of the TPFF based on the superficial temporal artery for mastoid obliteration. East and colleagues and Cheney and colleagues [23,24] describe the successful use of this robust 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. The TPFF is well vascularized, and accepts both full and split-thickness skin grafts. Figs. 8 through 10 illustrate the use of the TPFF for mastoid obliteration. There are numerous reports in the literature of the use of ceramic materials such as calcium phosphate ceramic granules and hydroxyapatite for mastoid obliteration. Hartwein and colleagues [25] describe the use of hydroxyapatite to obliterate the mastoid bowl while reconstructing the posterior canal wall with autologous conchal cartilage. Yung and colleagues [26] describe 34 cases of mastoid obliteration using hydroxyapatite granules and
Fig. 8. Dotted line outlines the TPFF supplied by the superficial temporal artery (A). (B) is the frontal branch of the facial nerve. (From Cheney ML, Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3; with permission.)
MASTOID OBLITERATION
1137
Fig. 9. (1) Skin/subcutaneous tissue; (2) TPFF; (3) loose areolar tissue; (4) temporalis muscle fascia; (5) temporalis muscle. (From Cheney ML Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3; with permission.)
Fig. 10. Canal wall-down mastoidectomy defect filled with the TPFF with its vascular pedicle (large arrowhead). (From Cheney ML, Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3; with permission.)
1138
MEHTA & HARRIS
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 [27]. Mahendran and colleagues [28] describe the use of hydroxyapatite cement for mastoid obliteration. In their series, however, there was a significant incidence of postoperative infection with 50% of the patients requiring revision surgery and removal of the foreign material. Total tympanomastoid obliteration Total tympanomastoid obliteration consists of obliteration of the entire mastoid, middle ear, and Eustachian tube. The indications for this procedure are outlined above. Rambo [3] described a technique for total tympanomastoid obliteration in cases in which there was no useful residual hearing. He obliterated the mastoid and middle ear with temporalis muscle followed by suturing shut the external auditory canal. As discussed later, histopathologic studies have shown that muscle tends to atrophy with time resulting in a cavity [29]. Our preferred technique for total tympanomastoid obliteration is outlined in detail. Following a canal wall-down mastoidectomy, this procedure involves transection of the external auditory canal with the auricle reflected anteriorly (Figs. 11 and 12). Removal of cartilage on the auricular side of the external canal is then performed (Fig. 13). As this cartilage is removed, care is taken not to buttonhole the skin. Anteriorly and posteriorly based skin flaps are then reflected onto the conchal side and sutured together in an H pattern (Fig. 14). This closure is intended to provide a water-tight seal effectively closing off the external auditory
Fig. 11. The external auditory canal is transected and the auricle is reflected anteriorly. (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
MASTOID OBLITERATION
1139
Fig. 12. The auricle is reflected anteriorly based on a small musculofascial pedicle. (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
meatus. The meatal closure can be reinforced by additional closure of soft tissue medially (Fig. 15). The Eustachian tube orifice is then identified in the middle ear. It is cleaned of all mucosa and burnished with a small diamond burr. The Eustachian tube is then obliterated with a plug of fascia followed by bone wax. The tympanomastoidectomy defect is then filled with an abdominal fat graft. If available, an inferiorly based periosteal flap, or alternatively, a TPFF, can be used to supplement the obliteration [17].
Fig. 13. Cartilage is removed from the auricle side of the external auditory canal. (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
1140
MEHTA & HARRIS
Fig. 14. The skin flaps are sutured together in an H pattern closing the external auditory meatus (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
Fig. 15. The meatal closure is reinforced medially by closure of additional soft tissue (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
MASTOID OBLITERATION
1141
Radiographic and histopathologic features of mastoid obliteration Radiographic features The radiographic features of mastoid obliteration have not been well studied. Yung and colleagues [30] examined the value of high-resolution CT in detecting recurrent cholesteatoma in ears that had previously undergone mastoid obliteration. Their study concluded that CT scanning was effective in detecting small epithelial pearls within a cavity obliterated with hydroxyapatite. However, in cavities obliterated with muscle, CT scanning was not as effective in detecting epithelial pearls. Further studies are needed to evaluate the radiographic features of each of the various techniques of mastoid obliteration and the ability to detect recurrent disease. Histopathology Palva [31] was the first to describe the histopathologic fate of tissues used in mastoid obliteration. He reported on three temporal bones that had undergone a meatally based musculoperiosteal flap for mastoid obliteration. Each of the bones showed viability of the musculoperiosteal flap with good vascularity. Linthicum [29] performed a more extensive histopathologic study of 17 temporal bones that had undergone mastoid obliteration with a variety of techniques. He concluded that fat and bone pate´ appear to maintain their original volume. However, muscle and subcutaneous tissue tended to atrophy with time. Bone pate´ used with a Palva type musculoperiosteal flap provided the best obliteration of a mastoid cavity.
References [1] Mosher HP. A method of filling the excavated mastoid with a flap from the back of the auricle. Laryngoscope 1911;21:1158–63. [2] Kisch J. Temporal muscle grafts in the radical mastoid operation. J Laryngol 1928;43:735. [3] Rambo JHT. Primary closure of the radical mastoidectomy wound; a technique to eliminate postoperative care. Laryngoscope 1958;68:1216–27. [4] Popper O. Periosteal flap grafts in mastoid operations. S Afr Med J 1935;9:77. [5] Palva T. Operative technique in mastoid obliteration. Acta Otolaryng 1973;75:289–90. [6] Palva T. Mastoid obliteration. Acta Otolaryngol Suppl 1979;360:152–4. [7] Dornhoffer JL. Surgical modification of the difficult mastoid cavity. Otolaryngol Head Neck Surg 1999;120:361–7. [8] Estrem SA, Highfill G. Hydroxyapatite canal wall reconstruction/mastoid obliteration. Otolarngol Head Neck Surg 1999;120:345–9. [9] D’arc MB, Daculsi G, Emam N. Biphasic ceramics and fibrin sealant for bone reconstruction in ear surgery. Ann Otol Rhinol Laryngol 2004;113:711–20. [10] Mills RP. Surgical management of the discharging mastoid cavity. J Laryngol Otol Suppl 1988;16:1–6. [11] Shea MC, Gardner G Jr, Simpson ME. Mastoid obliteration with bone. Otolaryngol Clin North Am 1972;5(1):161–72. [12] Roberson JB, Mason TP, Stidham KR. Mastoid obliteration: autogenous cranial bone pate reconstruction. Otol Neurotol 2003;24:132–40.
1142
MEHTA & HARRIS
[13] Kaylie DM, Horgan MJ, Delashaw JB, et al. A meta-analysis comparing outcomes of microsurgery and gamma knife radiosurgery. Laryngoscope 2000;110:1850–6. [14] Gal TJ, Kerschner JE, Futran ND, et al. Reconstruction after temporal bone resection. Laryngoscope 1998;108(4):476–81. [15] Kim CS, Chang SO, Lee HJ, et al. Cochlear implantation in patients with a history of chronic otitis media. Acta Otolaryngol 2004;124:1033–8. [16] Nadol JB Jr. Cochlear implantation and implantable hearing aids. In: Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 355–63. [17] Nadol JB Jr. Chronic otitis media. In: Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 199–218. [18] Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25: 873–8. [19] Moffat DA, Gray RF, Irving RM. Mastoid obliteration using bone pate´. Clin Otolaryngol 1994;19:149–57. [20] Montandon P, Benchaou M, Guyot JP. Modified canal wall-up mastoidectomy with mastoid obliteration for severe chronic otitis media. ORL 1995;57:198–201. [21] Vartiainen E, Harma R. Mastoid obliteration in intact canal wall mastoidectomy. Clin Otolaryngol 1987;12:327–9. [22] Gantz BJ, Wilkinson EP, Hansen MR. Canal wall reconstruction tympanomastoidectomy with mastoid obliteration. Laryngoscope 2005;115:1734–40. [23] East CA, Brough MD, Grant HR. Mastoid obliteration with the temporoparietal fascial flap. J Laryngol Otol 1991;105:417–20. [24] Cheney ML, Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3. [25] Hartwein J, Hormann K. A technique for the reconstruction of the posterior canal wall and mastoid obliteration in radical cavity surgery. Am J Otol 1990;11(3):169–73. [26] Yung MW. The use of hydroxyapatite granules in mastoid obliteration. Clin Otolaryngol 1996;21:480–4. [27] Gyllencreutz T. Reconstruction of the ear canal wall using hydroxylapatite with and without mastoid obliteration and by obliteration with bone chips. Acta Otolaryngol (Stock) 1992;(Suppl 492):144–6. [28] Mahendran S, Yung MW. Mastoid obliteration with hydroxyapatite cement: the Ipswich experience. Otol Neurotol 2004;25:19–21. [29] Linthicum FH. The fate of mastoid obliteration tissue: a histopathological study. Laryngoscope 2002;112:1777–81. [30] Yung MW, Karia KR. Mastoid obliteration with hydroxyapatitedthe value of high resolution CT scanning in detecting recurrent cholesteatoma. Clin Otolaryngol 1997;22:553–7. [31] Palva T, Karma P, Karja J, et al. Mastoid obliteration: histopathological study of three temporal bones. Arch Otolaryngol 1975;101:271–5.
Mastoid Obliteration Ritvik P. Mehta, MDa,*, Jeffrey P. Harris, MD, PhDb a
Department of Otology and Laryngology, Massachusetts Eye and Ear Infirmary/Harvard Medical School, Boston, MA, USA b Division of Otolaryngology/Head and Neck Surgery, Department of Surgery, University of California San Diego School of Medicine, 200 W. Arbor Drive, San Diego, CA 92103, USA
The concept of mastoid obliteration was first introduced in 1911 by Mosher to promote healing of a mastoidectomy defect [1]. Over the course of this century, there have been numerous reports detailing a variety of techniques of obliterating the mastoid cavity. The vast majority of obliteration techniques consist of either local flaps (muscle, periosteum, or fascia) or free grafts (bone, cartilage, hydroxyapatite, and so on) (Box 1). Mosher’s original description was that of a superiorly based postauricular soft tissue flap. Kisch described the use of a pedicled temporalis muscle flap that was expanded on by Rambo [2,3]. Popper [4] described the use of a periosteal flap used to line, rather than obliterate, the mastoid cavity. Palva [5] went on to describe a modification of Popper’s flap as a musculoperiosteal flap to obliterate the mastoid bowl. Palva [6] further added the use of bone chips and bone pate´ in combination with a musculoperiosteal flap. In addition to bone pate´, other materials that have been described as implants for mastoid obliteration include fat grafts, diced cartilage, fascia, bone chips, and ceramic materials such as hydroxyapatite [7–11].
Indications and contraindications The most common indication for mastoid obliteration is following canal wall-down tympanomastoidectomy for chronic otitis media. A canal walldown mastoid cavity, if not obliterated, can result in persistent otorrhea that can be difficult to control even with topical antibiotic therapy and frequent cleaning of the cavity. Other problems associated with a mastoid
* Corresponding author. E-mail address: [email protected] (J.P. Harris). 0030-6665/06/$ - see front matter Ó 2006 Elsevier Inc. All rights reserved. doi:10.1016/j.otc.2006.08.007
oto.theclinics.com
1130
MEHTA & HARRIS
Box 1. Techniques of mastoid obliteration Local flaps Meatally based musculoperiosteal flap (Palva flap) Inferiorly based periosteal-pericranial flap Superiorly based musculoperiosteal flap Temporalis muscle flap Temporoparietal fascial flap (TPFF) Free grafts Bone chips/bone pate´ Fat Cartilage Fascia Hydroxyapatite
cavity may include the need for frequent cleaning, difficulty with the use of a hearing aid, water intolerance due to a susceptibility to infection, and propensity to vertigo by a caloric stimulus such as warm/cold air or water [12]. Obliteration of the mastoid bowl is indicated to reduce the size of the cavity. It is ideally conducted as a primary procedure at the time of canal walldown mastoidectomy. However, for a problematic mastoid bowl with chronic otorrhea and nonhealing, mastoid obliteration can be performed as a secondary revision procedure. Total tympanomastoid obliteration, or obliteration of the entire mastoid, middle ear, and Eustachian tube, is used for the prevention as well as management of cerebrospinal fluid leaks emanating through the temporal bone. The most common complication following microsurgery for acoustic neuroma is cerebrospinal fluid leak at a rate of 10.9% according to a recent metaanalysis [13]. Tympanomastoid obliteration can be performed primarily when the translabyrinthine approach is used for acoustic neuroma resection. Alternatively, it is used as a means of surgical treatment of cerebrospinal fluid (CSF) leak that has failed to heal with conservative measures such as bed rest, head elevation, and lumbar drainage. Tympanomastoid obliteration can be used for other causes of CSF leak as well such as meningoencephaloceles with CSF otorrhea or rhinorrhea or severe temporal bone trauma. Another indication for tympanomastoid obliteration includes reconstruction following surgical treatment for malignancies of the temporal bone. The defect created by lateral, subtotal, or total temporal bone resection typically requires obliteration of the middle ear, Eustachian tube, and mastoidectomy defect. This is especially important if there is a concomitant CSF leak resulting from the malignancy or the resection. Large defects may require the use of pedicled flaps or free tissue transfer for reconstruction [14].
MASTOID OBLITERATION
1131
A special situation that may require tympanomastoid obliteration is cochlear implantation in patients with a history of chronic otitis media. This group of patients can be challenging because of the risks associated with foreign body implantation in a potentially infected space. Tympanomastoid obliteration has been used in this setting to provide complete eradication of infection and inflammation as well as to provide a protective soft tissue layer over the electrode array [15]. It can also be used in patients with labyrinthitis ossificans in whom a drill-out of the cochlea is required with removal of the posterior canal wall and tympanic membrane [16]. Tympanomastoid obliteration can be performed in cases of chronic otitis media in patients with no usable hearing. It is important that complete eradication of disease is achieved by the surgeon before tympanomastoid obliteration [3,17]. Box 2 lists the most common indications for mastoid and tympanomastoid obliteration. Relative contraindications to mastoid obliteration include persistent active disease (cholesteatoma, malignancy, or active infection) within the tympanomastoid cavity. An exception to this is an extensive malignancy that may require tympanomastoid obliteration following subtotal resection in preparation for radiation therapy.
Techniques Mastoid obliteration following chronic ear surgery As mentioned above, a vast array of techniques have been described for mastoid obliteration following canal wall-down mastoidectomy for chronic otitis media. The authors prefer the Massachusetts Eye and Ear Infirmary technique of mastoid obliteration using a combination of bone pate´ and an inferiorly based periosteal-pericranial flap [17,18]. This technique is
Box 2. Indications for mastoid/tympanomastoid obliteration Canal wall-down mastoidectomy Chronic otorrhea/nonhealing of mastoid bowl Translabyrinthine acoustic neuroma resection CSF leak Extensive temporal bone trauma Temporal bone resection for malignancy Cochlear implantation in patients with chronic otitis media Cochlear implantation requiring extensive drill-out with removal of posterior canal wall Treatment of chronic otitis media in ears with no useful hearing
1132
MEHTA & HARRIS
outlined in detail. A postauricular incision 2- to 3-mm posterior to the postauricular crease is used (Fig. 1). Fig. 2 illustrates the site of harvest of the flap. Superiorly, the plane of the temporalis fascia is identified. Inferiorly, the postauricular muscles are divided and the skin is elevated in a supraperiosteal plane both anteriorly as well as posteriorly (Fig. 3). The temporalis muscle is then separated from the underlying pericranium at the level of the temporal line. The muscle is retracted superiorly to expose 3- to 4-cm of pericranium above the temporal line. The flap is then outlined with electrocautery. The width of the flap is approximately 2- to 3-cm, with the anterior limit being just posterior the external auditory canal. The pericranial portion of the flap consists of an extension 3- to 4-cm above the temporal line deep to the temporalis muscle. The flap is elevated inferiorly using a periosteal elevator and electrocautery for any dense adhesions (Fig. 4). It is left pedicled at the mastoid tip. A canal wall-down mastoidectomy is then performed for eradication of the disease process. At the beginning of the mastoidectomy, bone pate´ is collected from the lateral mastoid cortex using a Sheehy Pate´ Collector (OtoMed, Lake Havasu City, Arizona). The bone pate´ is kept moist and can be irrigated with antibiotic solution. At the end of the canal wall-down procedure, the bone pate´ is used to obliterate the mastoid cavity (Fig. 5). The inferiorly pedicled periosteal-pericranial flap is then used to cover the bone pate´ (Fig. 6). The pericranial extension of the flap allows coverage of the superior most aspect of the mastoidectomy defect. It is critical to completely cover the bone pate´ with the flap. Any exposed areas of bone are covered with split thickness skin grafts. The Koerner flap is replaced anterior to the obliterated mastoid cavity. Surgical pearls for success with this technique include the following: 1) A well-saucerized mastoid cavity with no ridges or cavities
Fig. 1. Typical postauricular incision used for mastoid obliteration. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
MASTOID OBLITERATION
1133
Fig. 2. Outline of the harvest site for the inferiorly based periosteal-pericranial flap. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
2) Adequate meatoplasty 3) Split thickness skin grafting to enhance reepithelialization 4) Complete coverage of bone pate with the periosteal-pericranial flap or fascia 5) Maximal lowering of facial ridge to level of facial nerve 6) Adequate canalplasty to remove anterior canal bulge 7) Drilling out the mastoid tip to allow the flap to smoothly lay into the mastoidectomy defect Although the aforementioned technique of mastoid obliteration is the workhorse at our institution, many other techniques of mastoid obliteration
Fig. 3. Coronal section of postauricular soft tissue and bone. The postauricular incision is kept lateral to the temporalis fascia and mastoid periosteum. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
1134
MEHTA & HARRIS
Fig. 4. The temporalis muscle is retracted superiorly. A periosteal elevator is used to elevate the flap from a superior to inferior direction. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
have been described. Palva’s original description describes a meatally based musculoperiosteal flap in conjunction with the use of cortical bone chips and bone pate´ for mastoid obliteration [5,6]. Fig. 7 illustrates the use of an anteriorly based musculoperiosteal flap. Moffat and colleagues [19] describe the use of bone pate´ and a superiorly based temporalis musculoperiosteal flap for mastoid obliteration. Some authors even advocate the use of mastoid obliteration for canal wall-up mastoidectomy in an attempt to prevent
Fig. 5. Bone pate´ is used to obliterate the mastoid; particular attention is paid to obliterate the sinodural, retrofacial, and mastoid tip areas. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
MASTOID OBLITERATION
1135
Fig. 6. The periosteal-pericranial flap is used to cover the bone pate´ and line the remainder of the cavity. The anterior aspect of the flap lies just over the facial ridge. (From Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25:873–8; with permission.)
Fig. 7. Schematic illustrating the use of an anteriorly based musculoperiosteal flap for obliteration of the mastoid cavity. (From Smyth GDL, Toner JG. Mastoidectomy: canal wall down techniques. In Brackman DE, Shelton C, Arriaga MA, editors. Otologic surgery. Philadelphia (PA): WB Saunders; 1994. p. 235; with permission.)
1136
MEHTA & HARRIS
retraction pockets and recurrent cholesteatoma [20,21]. Montandon and colleagues [20] use cartilage to block the aditus and an abdominal fat graft for the canal wall-up mastoidectomy cavity. Gantz and colleagues [22] describe a ‘‘canal wall reconstruction’’ tympanomastoidectomy with mastoid obliteration. Their technique consists of removal of the posterior bony canal wall with a microsagittal 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 describe the use of the TPFF based on the superficial temporal artery for mastoid obliteration. East and colleagues and Cheney and colleagues [23,24] describe the successful use of this robust 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. The TPFF is well vascularized, and accepts both full and split-thickness skin grafts. Figs. 8 through 10 illustrate the use of the TPFF for mastoid obliteration. There are numerous reports in the literature of the use of ceramic materials such as calcium phosphate ceramic granules and hydroxyapatite for mastoid obliteration. Hartwein and colleagues [25] describe the use of hydroxyapatite to obliterate the mastoid bowl while reconstructing the posterior canal wall with autologous conchal cartilage. Yung and colleagues [26] describe 34 cases of mastoid obliteration using hydroxyapatite granules and
Fig. 8. Dotted line outlines the TPFF supplied by the superficial temporal artery (A). (B) is the frontal branch of the facial nerve. (From Cheney ML, Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3; with permission.)
MASTOID OBLITERATION
1137
Fig. 9. (1) Skin/subcutaneous tissue; (2) TPFF; (3) loose areolar tissue; (4) temporalis muscle fascia; (5) temporalis muscle. (From Cheney ML Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3; with permission.)
Fig. 10. Canal wall-down mastoidectomy defect filled with the TPFF with its vascular pedicle (large arrowhead). (From Cheney ML, Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3; with permission.)
1138
MEHTA & HARRIS
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 [27]. Mahendran and colleagues [28] describe the use of hydroxyapatite cement for mastoid obliteration. In their series, however, there was a significant incidence of postoperative infection with 50% of the patients requiring revision surgery and removal of the foreign material. Total tympanomastoid obliteration Total tympanomastoid obliteration consists of obliteration of the entire mastoid, middle ear, and Eustachian tube. The indications for this procedure are outlined above. Rambo [3] described a technique for total tympanomastoid obliteration in cases in which there was no useful residual hearing. He obliterated the mastoid and middle ear with temporalis muscle followed by suturing shut the external auditory canal. As discussed later, histopathologic studies have shown that muscle tends to atrophy with time resulting in a cavity [29]. Our preferred technique for total tympanomastoid obliteration is outlined in detail. Following a canal wall-down mastoidectomy, this procedure involves transection of the external auditory canal with the auricle reflected anteriorly (Figs. 11 and 12). Removal of cartilage on the auricular side of the external canal is then performed (Fig. 13). As this cartilage is removed, care is taken not to buttonhole the skin. Anteriorly and posteriorly based skin flaps are then reflected onto the conchal side and sutured together in an H pattern (Fig. 14). This closure is intended to provide a water-tight seal effectively closing off the external auditory
Fig. 11. The external auditory canal is transected and the auricle is reflected anteriorly. (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
MASTOID OBLITERATION
1139
Fig. 12. The auricle is reflected anteriorly based on a small musculofascial pedicle. (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
meatus. The meatal closure can be reinforced by additional closure of soft tissue medially (Fig. 15). The Eustachian tube orifice is then identified in the middle ear. It is cleaned of all mucosa and burnished with a small diamond burr. The Eustachian tube is then obliterated with a plug of fascia followed by bone wax. The tympanomastoidectomy defect is then filled with an abdominal fat graft. If available, an inferiorly based periosteal flap, or alternatively, a TPFF, can be used to supplement the obliteration [17].
Fig. 13. Cartilage is removed from the auricle side of the external auditory canal. (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
1140
MEHTA & HARRIS
Fig. 14. The skin flaps are sutured together in an H pattern closing the external auditory meatus (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
Fig. 15. The meatal closure is reinforced medially by closure of additional soft tissue (From Nadol JB Jr. Chronic otitis media. In Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 214–6; with permission.)
MASTOID OBLITERATION
1141
Radiographic and histopathologic features of mastoid obliteration Radiographic features The radiographic features of mastoid obliteration have not been well studied. Yung and colleagues [30] examined the value of high-resolution CT in detecting recurrent cholesteatoma in ears that had previously undergone mastoid obliteration. Their study concluded that CT scanning was effective in detecting small epithelial pearls within a cavity obliterated with hydroxyapatite. However, in cavities obliterated with muscle, CT scanning was not as effective in detecting epithelial pearls. Further studies are needed to evaluate the radiographic features of each of the various techniques of mastoid obliteration and the ability to detect recurrent disease. Histopathology Palva [31] was the first to describe the histopathologic fate of tissues used in mastoid obliteration. He reported on three temporal bones that had undergone a meatally based musculoperiosteal flap for mastoid obliteration. Each of the bones showed viability of the musculoperiosteal flap with good vascularity. Linthicum [29] performed a more extensive histopathologic study of 17 temporal bones that had undergone mastoid obliteration with a variety of techniques. He concluded that fat and bone pate´ appear to maintain their original volume. However, muscle and subcutaneous tissue tended to atrophy with time. Bone pate´ used with a Palva type musculoperiosteal flap provided the best obliteration of a mastoid cavity.
References [1] Mosher HP. A method of filling the excavated mastoid with a flap from the back of the auricle. Laryngoscope 1911;21:1158–63. [2] Kisch J. Temporal muscle grafts in the radical mastoid operation. J Laryngol 1928;43:735. [3] Rambo JHT. Primary closure of the radical mastoidectomy wound; a technique to eliminate postoperative care. Laryngoscope 1958;68:1216–27. [4] Popper O. Periosteal flap grafts in mastoid operations. S Afr Med J 1935;9:77. [5] Palva T. Operative technique in mastoid obliteration. Acta Otolaryng 1973;75:289–90. [6] Palva T. Mastoid obliteration. Acta Otolaryngol Suppl 1979;360:152–4. [7] Dornhoffer JL. Surgical modification of the difficult mastoid cavity. Otolaryngol Head Neck Surg 1999;120:361–7. [8] Estrem SA, Highfill G. Hydroxyapatite canal wall reconstruction/mastoid obliteration. Otolarngol Head Neck Surg 1999;120:345–9. [9] D’arc MB, Daculsi G, Emam N. Biphasic ceramics and fibrin sealant for bone reconstruction in ear surgery. Ann Otol Rhinol Laryngol 2004;113:711–20. [10] Mills RP. Surgical management of the discharging mastoid cavity. J Laryngol Otol Suppl 1988;16:1–6. [11] Shea MC, Gardner G Jr, Simpson ME. Mastoid obliteration with bone. Otolaryngol Clin North Am 1972;5(1):161–72. [12] Roberson JB, Mason TP, Stidham KR. Mastoid obliteration: autogenous cranial bone pate reconstruction. Otol Neurotol 2003;24:132–40.
1142
MEHTA & HARRIS
[13] Kaylie DM, Horgan MJ, Delashaw JB, et al. A meta-analysis comparing outcomes of microsurgery and gamma knife radiosurgery. Laryngoscope 2000;110:1850–6. [14] Gal TJ, Kerschner JE, Futran ND, et al. Reconstruction after temporal bone resection. Laryngoscope 1998;108(4):476–81. [15] Kim CS, Chang SO, Lee HJ, et al. Cochlear implantation in patients with a history of chronic otitis media. Acta Otolaryngol 2004;124:1033–8. [16] Nadol JB Jr. Cochlear implantation and implantable hearing aids. In: Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 355–63. [17] Nadol JB Jr. Chronic otitis media. In: Nadol JB Jr, McKenna MJ, editors. Surgery of the ear and temporal bone. 2nd edition. Philadelphia (PA): Lipincott Williams and Wilkins; 2005. p. 199–218. [18] Ramsey MJ, Merchant SN, Mckenna MJ. Postauricular periosteal-pericranial flap for mastoid obliteration and canal wall down tympanomastoidectomy. Otol Neurotol 2004;25: 873–8. [19] Moffat DA, Gray RF, Irving RM. Mastoid obliteration using bone pate´. Clin Otolaryngol 1994;19:149–57. [20] Montandon P, Benchaou M, Guyot JP. Modified canal wall-up mastoidectomy with mastoid obliteration for severe chronic otitis media. ORL 1995;57:198–201. [21] Vartiainen E, Harma R. Mastoid obliteration in intact canal wall mastoidectomy. Clin Otolaryngol 1987;12:327–9. [22] Gantz BJ, Wilkinson EP, Hansen MR. Canal wall reconstruction tympanomastoidectomy with mastoid obliteration. Laryngoscope 2005;115:1734–40. [23] East CA, Brough MD, Grant HR. Mastoid obliteration with the temporoparietal fascial flap. J Laryngol Otol 1991;105:417–20. [24] Cheney ML, Megerian CA, Brown MT, et al. Mastoid obliteration and lining using the temporoparietal fascial flap. Laryngoscope 1995;105:1010–3. [25] Hartwein J, Hormann K. A technique for the reconstruction of the posterior canal wall and mastoid obliteration in radical cavity surgery. Am J Otol 1990;11(3):169–73. [26] Yung MW. The use of hydroxyapatite granules in mastoid obliteration. Clin Otolaryngol 1996;21:480–4. [27] Gyllencreutz T. Reconstruction of the ear canal wall using hydroxylapatite with and without mastoid obliteration and by obliteration with bone chips. Acta Otolaryngol (Stock) 1992;(Suppl 492):144–6. [28] Mahendran S, Yung MW. Mastoid obliteration with hydroxyapatite cement: the Ipswich experience. Otol Neurotol 2004;25:19–21. [29] Linthicum FH. The fate of mastoid obliteration tissue: a histopathological study. Laryngoscope 2002;112:1777–81. [30] Yung MW, Karia KR. Mastoid obliteration with hydroxyapatitedthe value of high resolution CT scanning in detecting recurrent cholesteatoma. Clin Otolaryngol 1997;22:553–7. [31] Palva T, Karma P, Karja J, et al. Mastoid obliteration: histopathological study of three temporal bones. Arch Otolaryngol 1975;101:271–5.