SURGICAL MANAGEMENT OF PETROUS APEX CHOLESTEATOMA: OUR EXPERIENCE OF 15 CASES
Introduction
Petrous apex cholesteatoma (PAC) may involve the petrous bone as a congenital primary lesion or secondary to an acquired middle ear cholesteatoma.1–5 PAC surgery is challenging because complete removal of PAC matrix from the dura, sigmoid sinus, jugular bulb, internal carotid artery (IAC) and facial nerve is often difficult. The choice of surgical approach should be based on the location and extent of the lesion, and preoperative hearing and facial nerve functions.
Materials and methods
A retrospective analysis was conducted of the clinical charts of all patients with PAC (n = 15) at Osaka and Kinki University Hospitals from 1992 to 2012. During the same period, 1212 cases of cholesteatoma were surgically treated by the author. The prevalence of PAC, therefore, should be 15/1212 (1.2%). The mean age was 40 years and the age ranged from 19 to 80 years old. Female/male ratio was 4:11. Probable etiology was classified into congenital (N = 9), acquired (N = 4), and unknown (N = 1). Acquired cases had a history of chronic otitis media or had undergone previous middle-ear surgery elsewhere.
Results
The preoperative common symptoms were hearing loss (HL) (Fig. 1A; N = 15) and facial nerve palsy and weakness (N = 7). As for HL, mixed HL was present in three cases, conductive HL in four cases, profound sensorineural hearing loss (SNHL) in two cases, and total deafness in six cases (Fig. 1B). According to Sanna’s classification,2 the lesions confirmed at the surgery were classified into supra-labyrinthine (N = 9), massive labyrinthine (N = 5), and infra-labyrinthine (N = 1) groups (Fig. 2A). Middle cranial fossa (MFC) approach combined with lateral transtemporal approach was conducted in 12 cases, and transmastoid with/ without trans-labyrinthine approach was selected in three cases (Fig. 2B).
None of the eight patients with a pre-operative normal facial nerve function developed a facial palsy post-operatively. In three out of seven patients with a facial nerve palsy pre-operatively, facial-nerve function recovered somewhat post-operatively. The removal of PAC and infected bone with appropriate decompression of the nerve, might improve the facial-nerve function. None of the four patients with a pre-operative conductive HL developed deterioration in bone conduction post-operatively (hearing results were successful in three cases, moderate in one). One out of three patients with a pre-operative mixed HL developed a profound SNHL post-operatively.
Fig.1. The preoperative common symptoms and types of hearing loss.
Fig.2. The classification of the lesions and the surgical approaches.
Total PAC removal was completed in 13 cases. Because thin PAC matrix was found to be adhered extensively and tightly to the dura of middle and posterior cranial fossa, the wall of sigmoid sinus, jugular bulb, bipolar coagulation of suspected portions had been advocated to denature of the matrix in two cases. The mastoid and middle ear were explored at the second surgery in eight cases one year after the first stage surgery. Three residual PACs were confirmed and removed. The mean follow up was 49 months (range three to 192 months) and annual MRI scans showed no apparent suggestion of PAC recurrence in all of the 15 cases.
Discussion
The MFC approach can be used successfully to remove supra-labyrinthine PAC with or without an apical extension. A MFC approach offers the possibility of hearing preservation, but the exposure is often inadequate for removal of the more extensive lesions. The lateral transtemporal approach has two main advantages: it is the most direct route to the pathology, bone removal avoids dural retraction. For complete PAC removal, the most suitable approaches might be the lateral transtemporal (trans-labyrinthine-trans-cochlear) approach combined with the MFC approach. Following total PAC removal, the defect is usually closed in either of two ways: obliteration of the cavity and blind sac closure techniques, and the more traditional open cavity. The advantages of reconstruction and establishment of a pneumatized middle ear have been suggested: one is an easy detection of recurrent cholesteatoma on CT and MRI during follow up; the other is easy access to the petrous apex recurrent lesion because of an absence of barriers in the approach.
The main factors affecting the choice of surgical approach are: inaccessible nature of the petrous apex, the extent of disease, the degree of facial nerve and hearing functions, the need for the prevention of CSF leaks as well as the recurrence of the lesion. We believe that the adoption of a lateral transtemporal approach combined with a MFC approach and subsequent reconstruction of a well-aerated middle ear allows the greatest opportunity for total removal of the lesion, preservation of good neurological functions, and prevention of PAC recurrence.
1.Yanagihara N, Nakamura K, Hatakeyama T. Surgical management of petrous apex cholesteatoma: a therapeutic scheme. Skull Base Surg 2:22–27, 1992
2.Sanna M, Zini C, Gamoletti R, Frau N, Taibah AK, Russo A, Pasanisi E. Petrous bone cholesteatoma. Skull Base Surg 3:201–213, 1993
3.Moffat D, Jones S, Smith W. Petrous temporal bone cholesteatoma: a new classification and long-term surgical outcomes. Skull Base 18:107–115, 2008
4.Aubry K, Kovac L, Sauvaget E, Tran Ba Huy P, Herman P. Our experience in the management of petrous bone cholesteatoma. Skull Base 20:163–167, 2010
Address for correspondence: Katsumi Doi, MD/PhD, 377–2, Oono-Higashi, Osaka-Sayama, Osaka 589–8511, Japan. kdoi@med.kindai.ac.jp
Cholesteatoma and Ear Surgery – An Update, pp. 139–141
Edited by Haruo Takahashi
2013 © Kugler Publications, Amsterdam, The Netherlands