Tentorial Incision vs. Retraction of the Tentorial Edge during the Subtemporal Approach: Anatomical Comparison in Cadaveric Dissections and Retrospective Clinical Case Series

Abstract

Objective The aim of this study was to compare tentorial incision (group A) versus retraction and tack up suture (group B) of the tentorial edge during the subtemporal approach for surgery in the high basilar region.

Design 24 cadaveric dissections and 4 clinical cases of aneurysms of the high basilar region are presented. Assessment included visibility and operability afforded by either tentorial incision creating a dural flap (group A) or retraction of the tentorial edge and tethering with a suture (group B). Four patients, two with superior cerebellar artery aneurysms and two with proximal posterior cerebral artery aneurysms were treated with each approach.

Results In the quantitative evaluations, we found no significant difference in the exposure of the posterior cerebral, superior cerebellar, and perforant arteries as well as surgical working area provided by either approach. However, tentorial incision allowed a significantly greater exposure of the basilar artery and the fourth cranial nerve (both p < 0.001). Concerning operability, tentorial incision provided no objective advantage for direct clipping of the high basilar region (groups A vs. B, p > 0.05). Subjectively, clipping of the high basilar segment was feasible using tentorial tethering only.

Conclusion Retraction of the free edge of the tentorium downward by tethering with a suture is simple and fast method for exposure of aneurysms in the high basilar region when the pathology does not require a proximal control. In our data the rather more invasive and time consuming tentorial incision provided an additional objectified advantage only for placement of a proximal temporary clip.

Keywords

tentorial incision - tentorial retraction - tentorial tethering - subtemporal approach - high basilar aneurysm

Ethical Approval

The study was in accordance with the ethical standards of the institutional and national research committee and with the 1964 Helsinki declaration and its later amendments.

For this type of study formal consent is not required.

This article does not contain any studies with human participants or animals performed by any of the authors

• References

• 1 Hernesniemi J, Ishii K, Karatas A. , et al. Surgical technique to retract the tentorial edge during subtemporal approach: technical note. Neurosurgery 2005; 57 (4, Suppl): E408 , discussion E408
• 2 Spiller WG, Frazier CH. The division of the sensory root of the trigeminus for relief of tic douloureaux: an experimental pathological and clinical study with a preliminary report of one surgical successful case. Phila Med J 1901; 8: 1039-1049
• 3 Ardeshiri A, Ardeshiri A, Wenger E, Holtmannspötter M, Winkler PA. Subtemporal approach to the tentorial incisura: normative morphometric data based on magnetic resonance imaging scans. Neurosurgery 2006; 58 (1, Suppl): ONS22-ONS28 , discussion ONS22–ONS28
• 4 Hernesniemi J, Ishii K, Niemelä M, Kivipelto L, Fujiki M, Shen H. Subtemporal approach to basilar bifurcation aneurysms: advanced technique and clinical experience. Acta Neurochir Suppl (Wien) 2005; 94 (04) 31-38
• 5 Knosp E, Tschabitscher M, Matula C, Koos WT. Modifications of temporal approaches: anatomical aspects of a microsurgical approach. Acta Neurochir (Wien) Suppl 1991; 53: 159-165
• 6 Pichierri A, D'Avella E, Ruggeri A, Tschabitscher M, Delfini R. Endoscopic assistance in the epidural subtemporal approach and Kawase approach: anatomic study. Neurosurgery 2010; 67 (3, Suppl Operative): ons29-ons37 , discussion ons37
• 7 Wen DY, Heros RC. Surgical approaches to the brain stem. Neurosurg Clin N Am 1993; 4 (03) 457-468
• 8 Drake CG. Surgical treatment of ruptured aneurysms of the basilar artery. Experience with 14 cases. J Neurosurg 1965; 23 (05) 457-473
• 9 Drake CG. Bleeding aneurysms of the basilar artery. Direct surgical management in four cases. 1961. Can J Neurol Sci 1999; 26 (04) 335-340
• 10 Pescatori L, Niutta M, Tropeano MP, Santoro G, Santoro A. Fourth cranial nerve: surgical anatomy in the subtemporal transtentorial approach and in the pretemporal combined inter-intradural approach through the fronto-temporo-orbito-zygomatic craniotomy. A cadaveric study. Neurosurg Rev 2017; 40 (01) 143-153
• 11 Ammirati M, Ma J, Becker D, Black K, Cheatham M, Bloch J. Transzygomatic approach to the tentorial incisura: surgical anatomy. Skull Base Surg 1992; 2 (03) 161-166
• 12 Salma A, Wang S, Ammirati M. Extradural endoscope-assisted subtemporal posterior clinoidectomy: a cadaver investigation study. Neurosurgery 2010; 67 (3, Suppl Operative): ons43-ons48 , discussion ons48
• 13 Gonzalez LF, Amin-Hanjani S, Bambakidis NC, Spetzler RF. Skull base approaches to the basilar artery. Neurosurg Focus 2005; 19 (02) E3
• 14 Rhoton Jr AL. Tentorial incisura. Neurosurgery 2000; 47 (3, Suppl): S131-S153
• 15 McLaughlin N, Martin NA. Extended subtemporal transtentorial approach to the anterior incisural space and upper clival region: experience with posterior circulation aneurysms. Neurosurgery 2014; 10 (Suppl 1): 15-23 , discussion 23–24
• 16 Kockro RA, Killeen T, Ayyad A. , et al. Aneurysm surgery with preoperative three-dimensional planning in a virtual reality environment: technique and outcome analysis. World Neurosurg 2016; 96: 489-499