Bypass Surgery Of The Petrous Segment Of Internal Carotid Artery Via The Extended Middle Fossa Approach: An Mocrosurgical Anatomy And Animal Experimental Research

Part 1 Microsurgical Amatomy of the Petrous Segment of Internal Carotid Artery via the Extended Middle Fossa ApproachObjective The microsurgical anatomy of the petrous segment of internal carotid artery via the extended middle fossa approach was studied to establish an anatomic basis for surgical treatment.Methods Simulated surgery was performed on six adult cadaver heads which perfused by latex via the extended middle fossa approach.The appearance feature of the petrous segment of the internal carotid and its relationship with its surrounding structures were observed under microscope.Some anatomic parameters were measured.Results The petrous segment of the ICA can be divided into 3 segement and is of no vessel branches.The foramen spinosum,arcuate eminence,greater superficial petrosal nerve and geniculate ganglion are the important landmarks to define the surgical area.On average,the length of the horizontal petrous ICA exposed was9.1±1.1mm,that of the genu is 3.8±0.3mm,and that of the vertical segment is 10.2±1.5mm. Anterior retraction of V3 provided an additional 4.0±0.5mm of carotid exposure(P<0.05).The petrous segment of internal carotid artery,cochlear,internal acoustic meatus are important structures via the extended middle fossa approach.Conclusion The petrous segment of ICA has the advantage of little branches and large caliber,and it can be a optimal position for vascular bypass.Anterior retraction of V3 significantly adds the exposure of the petrous segment of ICA,which can provide longer operative distance for vascular bypass.The petrous ICA bypass via the extended middle fossa approach is an optimal surgical method for the lesions of this region.Part 2 Establishment of the high-volume extra-to intra-cranial internal carotid artery bypass model in canineObjective To establish the high-volume extra-to intra-cranial internal carotid artery bypass model in canine and proceed perioperative period observation for furthermore clinical use. We hope to form a curriculum on clinical training of this operation, and form a platform of mimic operation training for young neurosurgeons majored on this field.Methods Two high-volume extra-to intra-cranial internal carotid artery bypass operations were established in single side of two Beagle dogs. Angiography was taken after operations to observe whether these grafts were patent.Results The high-volume extra-to intra-cranial internal carotid artery bypass model were successfully established in two dogs. Angiography after operations showed that all grafts were patent.Conclusion The high-volume extra-to intra-cranial internal carotid artery bypass model were successfully established, which had similar material, high volume,similar blood pressure, high patent rate, providing a better mimic operation training platform.