Cranial base approaches to posterior circulation aneurysms

Abstract

<jats:p>Aneurysms arising from the posterior circulation, especially when they are large and complex, continue to present a technical challenge. The development of cranial base strategies and principles has added to surgical management options. The authors used one of four cranial base approaches for the treatment of 30 patients with large and/or complex aneurysms arising from the vertebrobasilar circulation. These approaches included the extradural temporopolar, combined petrosal, retrolabyrinthine-transsigmoid, and the extreme-lateral inferior transtubercular exposure. The indications, technique, and results of each approach in this series are discussed, and a management paradigm is suggested for such aneurysms.</jats:p>

Variations of the extreme-lateral craniocervical approach: anatomical study and clinical analysis of 69 patients

“…This technique is associated with a higher incidence of injury to the lower cranial nerves as well as the risk of injury to the VA or its branches. 5,12 Therefore, in our series, mobilizing the VA medially from approximately C-2 to the VB junction created a larger exposure. This technique allowed us to use this window to visualize the VB junction and to work anterior to the ninth through 12th cranial nerves.…”

“…Some authors report the partial drilling of the occipital condyle and jugular tubercle for VA and VB aneurysms without medial mobilization of the intradural VA. 5,12 The dura is reflected laterally, carrying with it the inferior portion of the sigmoid sinus and achieving a parallel sight to the intracranial course of the VA without brainstem retraction. 5 Nevertheless, to reach the VB junction and the area directly anterior to the spinomedullary junction, it is necessary to work between the 11th and 12th cranial nerves and the VA. This technique is associated with a higher incidence of injury to the lower cranial nerves as well as the risk of injury to the VA or its branches.…”

“…5,8,[22][23][24] By drilling various bony structures in that region, including the occipital condyle, jugular tubercle, and articular facets of C-1 and C-2, access to the normal anatomical structures and the pathological lesions is provided. 3,[6][7][8]15,18 Whether or not occipitocervical fusion becomes necessary depends on the type of approach that is performed.…”

Fronto-temporo-orbitozygomatic craniotomy and "half-and-half" approach for basilar apex aneurysms

“…[8,10,11] Medial ICA mobilization by sphenoid wing and ACP drilling and carotid collar division (carried out in one patient who had a short ICA with early bifurcation) further increases access to the BAA between the ICA and IIIrd nerve. [11,17,[21][22][23] Technical details During the "half and half" approach, certain surgical nuances helped in complication avoidance. [4,24] Fully exposing MCA in the sylvian fissure from ICA to MCA bifurcation prevented its kinking and consequent ischemia during fronto-temporal lobe retraction.…”

Jugular tubercle: morphometric analysis and surgical significance

“…The extent of bone removal in such procedures has undergone many modifications over the past 25 years. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][19][20][21] In 1986, Heros 11 published a detailed description of the extreme lateral inferior suboccipital approach for vertebral and vertebrobasilar artery lesions. One year later in 1987 Fukushima and colleagues 6,7 described the ELITE, which entailed resection of the JT.…”