Clinical Features and Outcomes in Patients with Non-Acoustic Cerebellopontine Angle Tumours

768 J Neurol Neurosurg Psychiatry 1999;66:768–771 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.66.6.768 on 1 June 1999. Downloaded from Clinical features and outcomes in patients with non-acoustic cerebellopontine angle tumours

Connor L Mallucci, Victoria Ward, A Simon Carney, Gerard M O’Donoghue, Iain Robertson

Abstract 90% of these tumours.1–4 Other sources of Objectives—Non-acoustic tumours of the tumour in this region include epidermal cell cerebellopontine angle diVer from ves- rests (giving rise to epidermoid cysts, dermoid tibular schwannomas in their prevalence, cysts, and cholesteatomata), arachnoid villi/ clinical features, operative management, granulations and the meninges (meningiomas, and surgical outcome. These features arachnoid cysts), primary intrinsic lesions were studied in patients presenting to the (gliomas, ependymomas), fat cells (lipomas), regional neuro-otological unit. tumours extending from the cranial base (for Methods—A retrospective analysis of example, glomus jugulare tumours), vascular clinical notes identified 42 patients with lesions (haemangiopericytomas), and second- non-acoustic tumours of the cerebello- ary tumours.12 pontine angle. Data were extracted re- The relation of each of these tumours to the garding presenting clinical features, bone of the cranial base varies greatly and has histopathological data after surgical re- implications for surgical management. Under- section, surgical morbidity and mortality, standing the precise relation of each tumour to and clinical outcome (mean 32 months the adjacent neural, vascular, and sensory follow up). structures is critically important if the best Results—The study group comprised 25 functional outcome is to be achieved after sur- 1 meningiomas (60%), 12 epidermoid cysts/ gical resection. Accurate preoperative diagno- cholesteatomata (28%), and five other sis of tumour type is therefore of the utmost tumours. In patients with meningiomas, importance in planning the optimal manage- 5–8 symptoms diVered considerably from pa- ment strategy for each patient. tients presenting with vestibular schwan- In addition, accurate diagnosis enables nomas. Cerebellar signs were present in informed discussion with patients about the 52% and hearing loss in only 68%. Twenty natural history of the untreated disease com- per cent of patients had hydrocephalus at pared with the potential risks of surgical and the time of diagnosis. After surgical resec- non-surgical management. tion, normal facial nerve function was The purpose of this study was to review the preserved in 75% of cases. In the epider- pattern of presentation of a consecutive series of non-acoustic tumours of the cerebellopon- moid group, fifth, seventh, and eighth http://jnnp.bmj.com/ nerve deficits were present in 42%, 33%, tine angle, to assess the ability to predict the and 66% respectively. There were no new histological diagnosis preoperatively, and to postoperative facial palsies. There were analyse the outcome of treatment. two recurrences (17%) requiring reoperation. Overall, there were two perioperative Department of deaths from pneumonia and meningitis. Patients and methods Patients were identified from a continually Neurosurgery —Patients with non-acoustic C L Mallucci Conclusions updated database of all cerebellopontine angle lesions of the cerebellopontine angle often on September 27, 2021 by guest. Protected copyright. V Ward tumours presenting to the combined otoneuro- present with diVerent symptoms and signs I Robertson surgical regional unit in Nottingham. Data from those found in patients with schwan- were recorded retrospectively from clinical Department of nomas. Hearing loss is less prevalent and notes and radiological imaging including CT Otolaryngology—Head cerebellar signs and facial paresis are and MRI (the second including both conven- and Neck Surgery, more common as presenting features. Queen’s Medical tional T1 and T2 images with and without Hydrocephalus is often present in patients Centre, Nottingham, contrast). More recently, MRI with construc- presenting with cerebellopontine angle UK tive interference in the steady state9 (CISS) A S Carney meningiomas. Non-acoustic tumours can G M O’Donoghue images has also been available. usually be resected with facial nerve pres- The following data were recorded: age, sex, ervation. Correspondence to: histological review, duration of symptoms, (J Neurol Neurosurg Psychiatry 1999;66:768–771) Mr G M O’Donoghue, clinical symptoms and signs, preoperative and Department of Otolaryngology—Head and Keywords: cerebellopontine angle; brain tumour; men- postoperative radiological investigations, surgi- Neck Surgery, Queen’s ingioma cal approach, complications, and subsequent Medical Centre, Nottingham progress. NG7 2UH, UK. Telephone 0044 115 924 9924; fax 0044 115 970 9748. Tumours of the cerebellopontine angle account for 8%–10% of all intracranial tumours. Results Received 15 June 1998 and Acoustic neuromas (vestibular schwannomas), Forty two patients were identified who had in revised form 11 December 1998 arising from the neurilemmal junction of the been treated by this department between 1980 Accepted 14 December 1998 vestibular nerve, account for between 80%– and 1996. There were seven men and 35 Non-acoustic cerebellopontine angle tumours 769 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.66.6.768 on 1 June 1999. Downloaded from

Clinical features and operative complications coverable (grade 3 or more) facial palsies recorded. Four patients had their lower cranial Epidermoids/ Meningiomas cholesteatomata nerves (ninth and 10th) aVected with diminished gag reflex and/or swallow. In one patient Symptom duration (median in months) 12 24 a long term tracheostomy was required. Other Hydrocephalus 20% 8% Cerebellar symptoms 52% 33% complications included third and 12th nerve Hearing loss (subjective) 32% 50% palsies which recovered spontaneously, a post- Hearing loss (objective) 68% 66% Preoperative fifth nerve symptoms 36% 42% operative haematoma that required emergency Preoperative seventh nerve symptoms 8% 33% evacuation, and four wound CSF leaks which Postoperative seventh nerve palsy (permanent) 2 (10%) 0 stopped spontaneously or with only a further Postoperative seventh nerve palsy (partial recovery) 3 (15%) 0 Postoperative absent gag/ swallow 4 (20%) 2 (25%) suture on the ward. Haematoma 1 0 There were two postoperative deaths. Both Infection 1 0 died in the month after surgery. The first patient, requiring the emergency evacuation of women, with a median age of 54 years. Median postoperative haematoma, died of aspiration follow up postsurgery was 3 years (range 8 pneumonia partially attributable to poor gag months-14 years). and swallow reflexes secondary to ninth/10th Patients with meningiomas (n=25) com- nerve palsies after surgery. The second patient prised most of the group, followed by patients succumbed to postoperative infection and ven- with epidermoid cysts/cholesteatomata triculitis and died from systemic sepsis. (n=12). Other lesions included two haemangiopericytomas, a metastatic adenocarcinoma, Follow up and an ependymoma. There have been no recurrences in patients with planned complete resections and in those MENINGIOMAS with known subtotal resections, the residuum is In our series, there were 25 patients with men- being followed up with regular imaging but ingiomas, 21 women and four men with a there have been no episodes of tumour median age of 55 years. Median duration of progression requiring reoperation to date. symptoms was 12 months. About half the patients had signs of cerebellar ataxia at presentation (table), with only a third present- EPIDERMOID CYSTS AND CHOLESTEATOMATA There were 12 patients with epidermoid cysts/ ing with subjective hearing loss. Two patients cholesteatomata, together comprising 29% of presented with facial pain, three with facial the total group. The median age was 42 years numbness, and four with symptoms of raised with a female:male ratio of 5:1. Median intracranial pressure. Only three patients had duration of symptoms was 24 months (table). tinnitus on direct questioning, but tinnitus was Symptomatic hearing loss as a presenting not a major presenting symptom. On pure tone symptom was present in 50% of patients (66% audiometry, 68% had evidence of asymmetric had diminished hearing on formal testing). (>10 dB four tone average) sensorineural hear- Thirty two per cent and 42% of patients ing impairment. respectively presented with facial nerve and Radiological work up included CT in 21 and

trigeminal nerve involvement. Other present- http://jnnp.bmj.com/ MRI in 16 patients. In all 20 patients operated ing symptoms and signs included four patients on with available histology and one in whom with cerebellar signs, one with dysphagia and pathology was obtained postmortem, the ra- one with diplopia. Only one patient had hydro- diological reports predicted a likely diagnosis cephalus and again none had tinnitus as a main of meningioma in all 21 patients giving 100% presenting symptom. predictive accuracy. Five patients (20%), had Radiological investigation included 10 CT hydrocephalus at presentation. scans and nine MRI scans. The suggested

radiological diagnosis in this group compared on September 27, 2021 by guest. Protected copyright. Surgical management of meningiomas with histological diagnosis was 88% accurate. Twenty patients went on to have surgical resections of which 13 (65%) were complete and seven (35%) were subtotal. The surgical Surgery approach was retrosigmoid in all but one Eight of the patients went on to have surgical patient, in whom a translabyrinthine approach resections of which ﬁve were complete exci- was used. Two patients who were elderly had sions and three were subtotal. Four patients ventriculoperitoneal shunts only. Two patients with small tumours are being followed up pro- with small tumours are being followed up with spectively with interval scanning. The ap- regular periodical scanning and the remaining proach was retrosigmoid in six and translaby- patient presented in extremis with hydrocepha- rinthine in two patients. lus and coma and died before any surgical intervention. Complications There have been no new facial palsies; two Complications of cerebellopontine angle patients had a diminished gag reﬂex postopera- meningioma surgery tively although neither have required tracheos- Complications are shown in the table. In 75% tomy. There was one CSF leak, which was suc- the facial nerve was spared, in three patients cessfully managed with further suturing to the there was partial recovery at follow up, wound. There were no infective complications reaching House and Brackman10 grades 1 or 2 and no mortality in this group of patients. and in only two patients were permanent unre- Postoperative hearing was unchanged (<10 dB 770 Mallucci, Ward,Carney, et al J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.66.6.768 on 1 June 1999. Downloaded from

4 tone average) in all patients undergoing non- much less prevalent in keeping with other destructive approaches. experiences.1819Formal preoperative and postoperative assessment of hearing in this group is Follow up essential and will not only have a bearing on the With a median follow up of 58 months there choice of surgical approach adopted but will have been two recurrences in the operated help clinicians to optimise resection techniques group, both patients in whom it was known to maximise the chance of some hearing that subtotal excisions had been performed. preservation. Both required reoperation due to the sympto- Trigeminal nerve symptoms are more promi- matic regrowth of residual tumour. nent in non-acoustic lesions18and particularly The four patients being treated conserva- with epidermoid cysts, are more likely to cause tively show no tumour progression to date. trigeminal pain than altered sensation.20 This is one symptom that can be gratifyingly improved Miscellaneous tumours by surgery. These included two haemangiopericytomas, We were surprised by the relative infre- one metastatic adenocarcinoma, one ependy- quency of reported tinnitus, (12%) which has moma, and one lesion of unknown histology. generally been found in association with Four of these have had surgery, with no recur- hearing loss in other series21119although others rences in the two patients with haemangioperi- have also pointed out that it is also an cytomas. Both patients with ependymoma and infrequent complaint in non-acoustic cerebel- adenocarcinoma have since re-presented with lopontine angle lesions.1 We have found no metastases at extracranial sites. cases of true rotatory vertigo such as have been reported by other workers.11 19 Discussion Overall symptomatology is still dependent Acoustic neuromas remain by far the most on tumour size and the exact location of the prevalent lesion to be found in the cerebello- lesion and we agree with others that there are pontine angle.4 Meningiomas are the second not enough clinical diVerences in presentation most common tumour to be found in this site, to allow preoperative diVerentiation from accounting for exactly 6.5% of all cases in two acoustic tumours on history and examination separate British series.211 Meningiomas ac- alone.12 There are, however, often relevant counted for 60% of our series, more than the clinical clues that should alert the clinician that 33% and 32% reported respectively in the the lesion may well be non-acoustic2 and this London11 and Cambridge2 series. These diVer- may be of importance if the radiological ences may reflect local referral practices. findings are inconclusive. Epidermoid cysts and cholesteatomata are Various approaches have been shown to be often included together in reported series and feasible in resecting tumours in the posterior if we combine numbers of the two patient fossa and have been well reviewed.21 Most of groups, they represent 29% of total numbers, our cases were exposed through a retrosigmoid more in keeping with the proportion found in approach. This has aVorded good visualisation other series.12 and allowed resection of the tumour without The clinical features of haemangiopericyto- recourse to excessive retraction. However, for mas, metastases, and other rare lesions of the the petroclival meningiomas a transpetrosal http://jnnp.bmj.com/ cerebellopontine angle have been well docu- approach has recently proved to us to have mented by other workers,12–18 and their rarity major advantages. In the patient with no pros- does not allow meaningful comparisons to be pect of useful postoperative hearing, a made about prevalence rates. translabyrinthine approach may be appropriate In this study, as in previous reports, non- especially for the tumours involving the inter- acoustic tumours of the cerebellopontine angle nal auditory meatus11 although it must always are more likely to present with cerebellar be remembered that hearing may occasionally symptoms than schwannomas.213 The most improve or even return to normal after the on September 27, 2021 by guest. Protected copyright. common complaint was of unsteadiness or resection of non-acoustic cerebellopontine falling persistently to one side and was accom- angle tumours22 23 and destructive approaches panied by clinically apparent ataxia. However, must therefore be used selectively. other symptoms associated with cerebellar dys- Despite using an approach that oVers function (for example, intention tremor and optimal exposure, certain clival meningiomas nystagmus) were uncommon findings. The lat- and extensive epidermoids are diYcult to ter infrequency in our series is a marked diVer- remove in their entirety without subjecting the ence from other workers’ findings with similar patient to unacceptable morbidity.1 Other numbers of patients presenting with ataxia.3 It studies have also included patients with has been reported that these symptoms are incomplete excisions.18 In the case of an often considered mild11 and this would seem to extensive epidermoid cyst, the tumour may be borne out by our study. Those patients who have extensive adherent capsule extensions presented primarily with cerebellar signs expe- folding around important structures.1 Clival rienced symptoms for a lengthy period (longer meningiomas may be adherent to the brain than the mean) before diagnosis. stem or may envelop arteries or nerves which Cranial nerve palsies were the main source of need to be preserved. Our study reinforces the prediagnosis morbidity with sensorineural view of others1 that, despite a relatively short hearing loss being the most common present- follow up, due to the biology of these tumours, ing symptom and sign. However, compared incomplete excision can still aVord good with acoustic neuroma series hearing loss is lifestyle with minimal morbidity for years with Non-acoustic cerebellopontine angle tumours 771 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.66.6.768 on 1 June 1999. Downloaded from

no essential requirement for further surgery. If 1 Lalwani AK. Meningiomas, epidermoids, and other nona- coustic tumors of the cerebellopontine angle. Otolaryngol repeat surgery is required, it may be at very Clin North Am 1992;25:707–28. infrequent intervals, often as long as a decade 2MoVat DA, Saunders JE, McElveen JT Jr, et al. Unusual 1 cerebello-pontine angle tumours. J Laryngol Otol 1993;107: apart. 1087–98. Because of the implications for surgical 3 Tekkok IH, Suzer T, Erbengi A. Non-acoustic tumors of the cerebellopontine angle. Neurosurg Rev 1992;15:117–23. management, it is essential that non-acoustic 4 Brackmann DE, Kwartler JA. A review of acoustic tumors: tumours of the cerebellopontine angle are cor- 1983–8. Am J Otol 1990;11:216–32. 2 5 Tator CH, Duncan EG, Charles D. Comparisons of the rectly diagnosed preoperatively. Fortunately, clinical and radiological features and surgical management with the availability of high quality MRI, an of posterior fossa meningiomas and acoustic neuromas. 1 Can J Neurol Sci 1990;17:170–6. accurate diagnosis can be made in most cases 6 Prasad S, Kamerer DB, Hirsch BE, et al. Preservation of although in one recent series, 25% of cerebel- vestibular nerves in surgery of the cerebellopontine angle: eVect on hearing and balance function. Am J Otolaryngol lopontine angle meningiomas were radiologi- 1993;14:15–20. cally thought to be vestibular schwannomas 7 Nedzelski J, Tator C. Other cerebellopontine angle (non- acoustic neuroma) tumors. J Otolaryngol 1982;11:248–52. and the exact nature of atypical tumours was 8 Grey PL, MoVat DA, Hardy DG. Surgical results in unusual only demonstrated in 67% of cases.8 Com- cerebellopontine angle tumours. Clin Otolaryngol 1996;21: 237–43. puted tomography does not always disclose the 9 Casselman JW, Kuhweide R, Deimling M, et al. Construc- nature of an atypical cerebellopontine angle tive interference in steady state-3DFT MR imaging of the 20 inner ear and cerebellopontine angle. Am J Neuroradiol lesion and there is no doubt that MRI is now 1993;14:47–57. the radiological investigation of choice.12Even 10 House JW, Brackmann DE. Facial nerve grading system. Otolaryngol Head Neck Surg 1985;93:146–7. with contrast enhanced MRI, small lesions may 11 Thomas NW, King TT. Meningiomas of the cerebellopon- 24 still be radiologically similar to schwannomas tine angle. A report of 41 cases. Br J Neurosurg 1996;10:59–68. and complex new imaging techniques such as 12 Anderson C, KrutchkoV D, Ludwig M. Carcinoma of the CISS may be necessary to show the true nature lower lip with perineural extension to the middle cranial 9 fossa. Oral Surgery Oral Medicine Oral Pathology 1990;69: and anatomy of a non-acoustic lesion. We 614–18. would recommend the use of CISS MRI 13 Brackmann DE, Bartels LJ. Rare tumors of the cerebello- sequences when there is any doubt as to the pontine angle. Otolaryngol Head Neck Surg 1980;88:555–9. 14 Cohen DL, Diengdoh JV, Thomas DG, et al. An intracranial exact nature of a cerebellopontine angle mass. metastasis from a PRL secreting pituitary tumour. Clin A detailed discussion on the radiological diag- Endocrinol (Oxf) 1983;18:259–64. 15 Kohan D, Downey LL, Lim J, et al. Uncommon lesions pre- nosis of non-acoustic tumours is beyond the senting as tumors of the internal auditory canal and scope of this paper and has been well covered cerebellopontine angle. Am J Otol 1997;18:386–92. 1 2 25–28 16 McMenomey SO, Glasscock ME 3rd, Minor LB, et al. by other authors. Facial nerve neuromas presenting as acoustic tumors. Am J Whereas vestibular schwannomas rarely Otol 1994;15:307–12. 17 Minami M, Hanakita J, Suwa H, et al. Solitary metastasis of recur after complete resection, this is not the lung cancer to the cerebellopontine angle: case report. case for other cerebellopontine angle lesions.8 Neurol Med Chir (Tokyo) 1996;36:172–4. 18 Molnar P, Nemes Z. Hemangiopericytoma of the cerebello- Ten to 13% of patients with cerebellopontine pontine angle. Diagnostic pitfalls and the diagnostic value angle meningiomas develop recurrent disease, of the subunit A of factor XIII as a tumor marker. Clin Neuropathol 1995;14:19–24. thought to be due to inadequate bone removal 19 Baguley DM, Benyon GJ, Grey PL, et al. Audio-vestibular at the time of initial surgery or the persistence ﬁndings in meningioma of the cerebello-pontine angle: a 811 retrospective review. J Layngol Otol 1997;111:1022–6. of tumour within the dura. Although some 20 Fitt AW, Pigott TJ, Marks PV.Undiagnosed epidermoid cyst series report good results after the resection of presenting as trigeminal neuralgia: a need for MRI. Br J 8 Neurosurg 1994;8:101–3. epidermoid cysts/cholesteatomata, other 21 Yasargil MG, Morarara RW,Cicur CM. Meningiomas of the workers have found that they are notoriously basal posterior fossa. In: Krayenbuhl H, ed. Advances and http://jnnp.bmj.com/ 29 30 technical standards in neurosurgery. New York: Springer- prone to recurrence and long term follow Verlag, 1980:3–115. up is essential. Rarer lesions have an even 22 Vellutini EA, Cruz OL, Velasco OP, et al. Reversible hearing loss from cerebellopontine angle tumors. Neurosurgery higher rate of recurrence and regular follow up 1991;28:310–2. and rescanning of patients with these rare 23 Cane MA, Lutman ME, O’Donoghue GM. Transiently 2 evoked otoacoustic emissions in patients with cerebello- tumours is essential. pontine angle tumors. Am J Otol 1994;15:207–16. 24 Bassi P, Piazza P, Cusmano F, et al. MR cisternography of the cerebello-pontine angle and internal auditory canal in Conclusion diagnosis of intracanalicular acoustic neuroma. Neuroradi- Non-acoustic tumours of the cerebellopontine ology 1990;31:486–91. on September 27, 2021 by guest. Protected copyright. 25 Helie O, Soulie D, Sarrazin JL, et al. Magnetic resonance angle often present with a diVerent range of imaging and meningiomas of the posterior cerebral fossa: symptoms and signs to those found in patients 31 cases. J Neuroradiol 1995;22:252–70. 26 Lalwani AK, Jackler RK. Preoperative diVerentiation with schwannomas. Hearing loss is less preva- between meningioma of the cerebellopontine angle and lent and cerebellar signs and facial paresis are acoustic neuroma using MRI. Otolaryngol Head Neck Surg 1993;109:88–95. more common as presenting features. Hydro- 27 Mawhinney RR, Buckley JH, Worthington BS. Magnetic cephalus is often present in patients presenting resonance imaging of the cerebello-pontine angle. Br J Radiol 1986;59:961–9. with cerebellopontine angle meningiomas. 28 Mafee MF, Kumar A, HeVner DK. Epidermoid cyst (chole- All non-cerebellopontine angle lesions are steatoma) and cholesterol granuloma of the temporal bone and epidermoid cysts aVecting the brain. Neuroimaging Clin more prone to recurrence than acoustic neuro- NAm1994;4:561–78. mas and long term follow up is recommended. 29 De Micheli E, Bricolo A. The long history of a cerebello-pontine angle epidermoid tumour: a case report Useful hearing can be preserved in a high pro- and lessons learned. Acta Neurochir (Wien) 1996;138:350– portion of cases and these rare tumours can 4. usually be resected with preservation of facial 30 Parikh S, Milosevic M, Wong CS, et al. Recurrent intracranial epidermoid cyst treated with radiotherapy. J Neuroon- nerve function. col 1995;24:293–7.