Petrosal approach: anatomical study and report of ten surgical cases of petroclival meningiomasTHESES
Petrosal approach: anatomical study and report of ten surgical cases of petroclival meningiomas (Abstract)*. Thesis. São Paulo, 1994.
Roberto Leal Silveira**
The crucial difficulties while performing this approach are related to the preservation of the dural venous sinuses and the vein of Labbé, and the amount of retraction required on the temporal lobe and cerebellum.
An anatomical study of the petrosal approach was carried out in both sides of 20 cadaver heads and 10 dry skulls. Also, the surgical results of 10 patients with petroclival meningiomas operated on by the same route were analysed.
Presently, the studies have suggested the need of some alternative techniques to overcome the difficulties of this approach as follows: 1) to perform the retrolabyrinthine stage before the craniotomy, to prevent tearing of the dural venous sinuses; 2) to extend the craniotomy both in a temporo-occipital and temporo-anterior direction, respectively, to diminish the retraction on the cerebellum and the temporal lobe, and to allow a safer retraction on the temporal lobe; 3) to perform the tentoriotomy without retracting the temporal lobe, which avoids tension on the vein of Labbé.
The anatomical study and the surgical results obtained in those patients suggest that the petrosal approach allows a wide access to the petroclival region and consequently the possibility of a petroclival meningiomas radical excision, with low morbidity and mortality.
Key words: meningioma, petrosal approach, skull base surgery, temporal lobe damage, superficial temporal vein.
