Surgical management of medium and large petroclival meningiomas: benchmark and limits
March 2016, Volume 158, Issue 3, pp 407–408 | Cite as
Surgical management of medium and large petroclival meningiomas: benchmark and limits
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Editorial (by Invitation)
First Online: 04 January 2016
Da Li and co-workers present a detailed sub-analysis of their series of petroclival meningiomas, which is the largest monocentric series published to date [5, 6]. In the current work, they restrict the analysis to medium and large tumours of more than 2 cm in diameter—the tumours that really cause difficulties for microsurgery as well as stereotactic radiosurgery. Gross total resection was achieved in 56 % of patients; dysfunctions of the cranial nerves were the most common complication and occurred in two-thirds of the patients. Immediately following surgery, morbidity temporarily increased and the Karnovsky Performance Scale temporarily decreased on average. The case fatality rate amounted to 2 %. Permanent surgical morbidity remained in 20 % of patients during the average long-term follow-up of almost 10 years, but significantly more patients lived independently after than before surgery (61 vs 46 %). One-fourth of patients were lost to long-term follow-up, so that the numbers regarding long-term outcome must be appreciated with sound judgment.
These key data focusing on medium and large petroclival meningioma are important, although difficult to compare with the smaller unselected series [1, 3, 7, 8, 9, 12]. Petroclival meningiomas smaller than 2 cm carry a much smaller surgical risk than large tumours, and in unselected series the small tumours dilute information regarding the problematic larger tumours. Numbers for the rate of gross total resection and surgical morbidities given in the published unselected series differ widely: gross total resection between one-third and two-thirds, and surgical morbidity also between one-third and two-thirds.
Stereotactic radiosurgery is an obvious alternative for primary treatment of these tumours. There are not very many reports—a fact that reflects concerns regarding tolerance in view of the vicinity of the brainstem. The Pittsburgh group reported their experience in a series of 39 patients with a median follow-up period of 37 months. Neurological status improved in 21 %, remained stable in 66 %, and eventually worsened in 13 %. Tumour volumes decreased in 23 %, remained stable in 68 % and increased in 8 % . It appears that there is some kind of consensus that radiosurgery is an adjuvant modality for larger petroclival meningiomas, which cannot be recommended as first-line therapy. However, there is little doubt that in analogy to vestibular schwannomas, stereotactic radiosurgery has evolved to an alternative for small-sized meningiomas.
The substantial proportion of incomplete removal in most series and the significant rate of morbidity suggest that petroclival meningiomas remain not only difficult but basically problematic for microsurgery. Finding the balance between radicality and risk is the real challenge of managing petroclival meningiomas. The surgical risk appears to be influenced by (1) tumour size, (2) consistency and texture of the tumour and (3) the interface between tumour and arteries, brainstem and cranial nerves. In my opinion, it is hardly possible to dissect an adherent or even encased pontine artery from the tumour.
Better presurgical imaging should provide more information with regard to tumour consistency and interface to vital structures. The techniques to define mechanical properties are partially already available, but they must be integrated into clinical routine [10, 11, 15]. The techniques to define interfaces are also available with the heavily contrasted T2- weighted series such as (constructive interference in steady state [CISS]). Although it appears highly desirable to know prior to surgery exactly what to expect, it remains an open issue knowing exactly whether to expect a soft tumour or a hard, rubber-like one makes a difference at the end in a situation where there is no reasonable treatment alternative. Regarding the interface to neighbouring structures, exact presurgical knowledge most likely makes a real difference, since dissection should not even be tried if the images suggest encasement of small pontine arteries.
In the current series of Li et al., intraoperative neurophysiological monitoring did not play a role. The patients were operated upon between 1993 and 2003. Today intraoperative neurophysiological monitoring certainly belongs to the standard procedure, although it is less helpful than, for example, with vestibular schwannomas . Petroclival meningiomas are in contact with multiple cranial nerves that are partially difficult or impossible to monitor. Regarding long-tract evoked potentials, electrophysiological monitoring can reliably identify damage related to surgical microdissection within the vicinity of the brainstem. The damage is, however, most often of ischaemic nature and not reversible.
The approach to petroclival meningioma is also an issue of continuing discussion [2, 7, 12, 14]. Li et al. based their surgical approach selection on tumour features, patient age and co-morbidities, and the surgeon’s preference. The presigmoid approach was used in cases in which the tumour was low and limited to below the IAC with broad attachment to the posterior petrous surface and partial extension into the middle fossa. The subtemporal transtentorial approach was used when the tumour’s lower limit was above and medial to the IAC. Extended middle fossa approaches including zygoectomy and partial petrosectomy were used when the tumour extended anterior-superiorly to the sellar region and inferiorly to the mid-clivus. The retrosigmoid approach was used when broad attachment to the posterior petrosal surface without middle fossa invasion was present. I would agree with this concept. As the authors state, the surgeon’s preference is important. Many tumours can be approached by the subtemporal route as well as by the retrosigmoid route.
Li and co-authors conclude from their analysis that radically aggressive resection might not be judicious in terms of postoperative morbidity. There is little to add to the conclusion. The challenge associated with large petroclival meningiomas is not of surgical or technical nature; the challenge is to find the right balance between acceptable risk and radicality. The challenge lies in the preoperative and intraoperative judgment by the surgeon.
Almefty R, Dunn IF, Pravdenkova S, Abolfotoh M, Al-Mefty O (2014) True petroclival meningiomas: results of surgical management. J Neurosurg 120(1):40–51CrossRefPubMedGoogle Scholar
Aoyagi M, Kawano Y, Tamaki M, Tamura K, Ohno K (2013) Combined extradural subtemporal and anterior transpetrosal approach to tumors located in the interpeduncular fossa and the upper clivus. Acta Neurochir (Wien) 155(8):1401–1407CrossRefGoogle Scholar
Ichimura S, Kawase T, Onozuka S, Yoshida K, Ohira T (2008) Four subtypes of petroclival meningiomas: differences in symptoms and operative findings using the anterior transpetrosal approach. Acta Neurochir (Wien) 150(7):637–645CrossRefGoogle Scholar
Kodama K, Javadi M, Seifert V, Szelényi A (2014) Conjunct SEP and MEP monitoring in resection of infratentorial lesions: lessons learned in a cohort of 210 patients. J Neurosurg 121(6):1453–1461CrossRefPubMedGoogle Scholar
Li D, Hao SY, Wang L, Tang J, Xiao XR, Zhou H, Jia GJ, Wu Z, Zhang LW, Zhang JT (2013) Surgical management and outcomes of petroclival meningiomas: a single-center case series of 259 patients. Acta Neurochir (Wien) 155(8):1367–1383CrossRefGoogle Scholar
Li D, Tang J, Ren C, Wu Z, Zhang LW, Zhang JT (2016) Surgical management of medium and large petroclival meningiomas: a single institution’s experience of 199 cases with long-term follow-up. Acta Neurochir (Wien). doi: 10.1007/s00701-015-2671-6
Morisako H, Goto T, Ohata K (2015) Petroclival meningiomas resected via a combined transpetrosal approach: surgical outcomes in 60 cases and a new scoring system for clinical evaluation. J Neurosurg 122(2):373–380CrossRefPubMedGoogle Scholar
Nanda A, Javalkar V, Banerjee AD (2011) Petroclival meningiomas: study on outcomes, complications and recurrence rates. J Neurosurg 114(5):1268–1277PubMedGoogle Scholar
Natarajan SK, Sekhar LN, Schessel D, Morita A (2007) Petroclival meningiomas: multimodality treatment and outcomes at long-term follow-up. Neurosurgery 60(6):965–979, discussion 979–81CrossRefPubMedGoogle Scholar
Ortega-Porcayo LA, Ballesteros-Zebadúa P, Marrufo-Meléndez OR, Ramírez-Andrade JJ, Barges-Coll J, Tecante A, Ramírez-Gilly M, Gómez-Amador JL (2015) Prediction of mechanical properties and subjective consistency of meningiomas using T1−T2 assessment versus fractional anisotropy. World Neurosurg 84(6):1691-1698CrossRefPubMedGoogle Scholar
Romani R, Tang WJ, Mao Y, Wang DJ, Tang HL, Zhu FP, Che XM, Gong Y, Zheng K, Zhong P, Li SQ, Bao WM, Benner C, Wu JS, Zhou LF (2014) Diffusion tensor magnetic resonance imaging for predicting the consistency of intracranial meningiomas. Acta Neurochir (Wien) 156(10):1837–1845CrossRefGoogle Scholar
Seifert V (2010) Clinical management of petroclival meningiomas and the eternal quest for preservation of quality of life: personal experiences over a period of 20 years. Acta Neurochir (Wien) 152(7):1099–1116CrossRefGoogle Scholar
Subach BR, Lunsford LD, Kondziolka D, Maitz AH, Flickinger JC (1998) Management of petroclival meningiomas by stereotactic radiosurgery. Neurosurgery 42(3):437–443, discussion 443–5CrossRefPubMedGoogle Scholar
Tatagiba M, Rigante L, Mesquita Filho P, Ebner FH, Roser F (2015) Endoscopic-assisted posterior intradural petrous apicectomy in petroclival meningiomas: a clinical series and assessment of perioperative morbidity. World Neurosurg 84(6):1708-1718CrossRefPubMedGoogle Scholar
Watanabe K, Kakeda S, Yamamoto J, Ide S, Ohnari N, Nishizawa S, Korogi Y (2015) Prediction of hard meningiomas: quantitative evaluation based on the magnetic resonance signal intensity. Acta Radiol. pii: 0284185115578323Google Scholar
© Springer-Verlag Wien 2016
Authors and Affiliations
Hans-Jakob Steiger12Email author1.Department of NeurosurgeryHeinrich-Heine-UniversitätDüsseldorfGermany2.Neurochirurgische Klinik, UniversitätsklinikumDüsseldorfGermany