承接上篇神外风云人物志Vinko V. Dolenc教授，笔者的思绪飘荡，不禁想起前床突磨除的点点滴滴。
2005年01月，杂志NEUROSURGERY ， Albert L. Rhoton教授的文章：Microsurgical Anatomy and Approaches to the Cavernous Sinus，有如下几句话，值得反复体会。
The anterior clinoid process is attached to the cranial base at three sites: first, to the lesser
sphenoid wing; second, through its anterior root, which forms the roof of optic canal; and
third, through its posterior root or optic strut, which forms the floor of the optic canal.
Drilling the lesser sphenoid wing extradurally detaches the clinoid from the lesser wing, and
the other attachments are released by opening the optic canal roof and drilling the optic strut.
Rhoton教授，前后使用词汇attached 及detaches， 选词用词之考量，前后平行之对比，押尾韵之阅读美感，令笔者拍案叫绝，交感兴奋！笔者认为：这是Rhoton教授使用其母语英语，不经意间地随手落笔；这更是Rhoton教授多年写作训练，潜移默化地顺理成章。
在笔者的文献资料中，2005年05月，杂志J Neurosurg，Akio Noguchi的文章，Extradural anterior clinoidectomy，也有几句话，值得体会。
The extradural anterior clinoidectomy procedure coupled with the opening of the optic sheath was introduced into the neurosurgical armamentarium in 1985 by Dolenc. The procedure allows
for the complete removal of the ACP with minimal brain retraction, while the dura mater acts as a natural barrier to protect neurovascular structures and does not expose the subarachnoid space to bone debris.
One can safely disengage the ACP from its three supporting structures:
1) the lesser wing of the sphenoid bone; 2) the roof of the optic canal; and 3) the optic strut.
Finally, the ACP is centrally hollowed prior to its extirpation to avoid damage to the oculomotor nerve, which is very close to the lateral underside of the ACP. The technique presented here represents further refinements to the original Dolenc procedure and its derivatives.
日本学者Akio Noguchi，在讲述前床突磨除时，使用的词汇是Supporting。Three supporting structures，是指蝶骨小翼、视神经管顶、视柱。
描写相同的内容，彼此选词与用词，实有细微差别。笔者认为，Rhoton教授的Attached，汉译为“附着”， 有从上向下着眼观察前床突的意味；而日本Akio Noguchi的Supporting，汉译为“支持、支撑”， 有从下向上着眼观察前床突的意味。
最后，请大家思考： Albert L. Rhoton教授的文章Microsurgical Anatomy and Approaches to the Cavernous Sinus，其中提到中床突的概念，middle clinoid，那么中床突是否也属于前床突的supporting structures呢？
Akio Noguchi的文章：Extradural anterior clinoidectomy，用硬膜外前床突磨除的10个步骤（Extradural Removal of the ACP，procedural step 1-10），分别比较了：
1. 1985年， Dolenc教授，采用翼点入路前床突磨除方法；
2. 1994年， Day教授，采用眶颧入路前床突磨除方法；
3. 1997年， Yonekawa，采用翼点入路前床突磨除方法；
4. 2005年， Akio Noguchi，采用眶颧入路前床突磨除方法。
来自西雅图的Laligam N. Sekhar教授，在给文章REFINEMENT OF THE EXTRADURAL ANTERIOR CLINOIDECTOMY: SURGICAL ANATOMY OF THE ORBITOTEMPORAL PERIOSTEAL FOLD，Neurosurgery 61[ONS Suppl 2]:ONS179–ONS186, 2007进行评论时，表达这样的观点：对于床突附近的动脉瘤处理，建议使用硬膜内前床突磨除。
Laligam N. Sekhar：However, in performing clinoidectomy for intracranial aneurysms that are located close to the clinoid process (e.g., clinoidal aneurysms, posterior paraclinoid aneurysms, giant paraclinoid aneurysms), I prefer to use an intradural technique.
来自凤凰城的Robert F. Spetzler教授，在给此文章进行评论时，表达类似的观点：眼动脉瘤处理，建议使用硬膜内前床突磨除。
Robert F. Spetzler：At our institution, we most frequently use an anterior clinoidectomy for ophthalmic aneurysms. Recognizing that an extradural approach is reasonable, we prefer an intradural approach for several reasons. First, the degree of anterior clinoidectomy required is best known at the time of aneurysm exposure, which enables us to avoid extra drilling and save time. Furthermore, aneurysm adhesions are best visualized from an intradural approach. For this application, we have found the ultrasonic claw dissector (Synergetics, St. Charles, MN) to be a safe alternative to the air drill.
Vinko V. Dolenc教授，是前床突磨除的权威大家。此文章的评论部分，其压轴之作便是来自Dolenc教授。笔者愿将其评论部分完整呈现，请有志于学的同道，仔细体会Laligam N. Sekhar教授、Robert F. Spetzler教授与Dolenc教授，观点的不同之处。
Froelich et al. present resection of the anterior clinoid process (ACP), which is systematically and anatomically very correctly described. It is true that for a long time, many neurosurgeons dealing with the pathologies in this region were reluctant to use the extradural approach and to perform clinoidectomy because there was too little space. This is why many of them preferred to perform partial clinoidectomy from the intradural side. With all due respect to these neurosurgeons, the intradural clinoidectomy, in particular for vascular lesions, should be avoided because it is too dangerous.
We now have at hand a description of the extended extradural approach with which the ACP is nicely visualized from the inferolateral side, so that the initial steps of drilling the ACP start on the opposite side from the possible aneurysm and the usual position of the optic nerve and the internal carotid artery. This approach has been repeatedly described and published (1–3, 5). If this fact is not convincing, then the latest publication (4) does summarize more than 2000 patients with pathologies at the central cranial base for whom the anterior clinoidectomy was routinely performed. In all of this clinical work, not a single patient suffered any morbidity as a result of ACP resection. The experience collected through experimental, neuroanatomical, and in particular, clinical work, gives us sufficient experience to objectively defend the extradural ACP resection as opposed to the intradural one.
Each individual patient requires detailed discussion and relevant consideration of the underlying anatomical circumstances. Most important of these are pneumatization of the ACP, and/or pneumatization of the walls of the optic canal, as well as erosion of the ACP as a result of pathologies (trigeminal schwannomas, aneurysms, parasellar hemangiomas) in contrast with hypertrophy of the ACP caused by ACP meningiomas (in particular, en plaque meningiomas). There is no doubt that in aneurysm pathology, the origin of the aneurysm as well as the circumference of the ICA, from which the pathology originates, are important factors. Clinoidectomy should be performed from the opposite side to where the pathology is located, and this is only possible when the ACP is sufficiently exposed by cutting the duplicature of the dura and connecting the temporal lobe and the periosteum of the orbital cavity, thereby providing safe passage to the neural and vascular structures from the parasellar to the orbital space.
One can agree that ACP resection offers an important additional corridor to reach different pathologies in the central cranial base in addition to the parasellar space and around the ACP. This is an important reason why all of the approaches to the pathologies at the dorsum sellae as well as in the retrosellar and clival regions and/or the region of the oculomotor trigone and even more posteriorly require ACP resection. Personally, I’m convinced that without practical knowledge of performing this procedure, every neurosurgeon will have problems dealing with the pathologies in the central cranial base regions.
Again, personally, I wouldn’t describe the ACP resection as very dangerous. I would rather describe it as a difficult procedure that requires a lot of training via microanatomical dissections in the laboratory to achieve the mandatory skill required to dare to perform it. We should not put fear into the bones of young neurosurgeons; we have to convince them that they must acquire skill in the laboratory to accept the truth that everything is experience-dependent.
I would like to add that, despite the long list of references, the most important (the Pioneer’s) is still missing.
Vinko V. Dolenc
1. Dolenc VV: Anatomy and Surgery of the Cavernous Sinus. Wien, Springer-Verlag, 1989.
2. Dolenc VV: Frontotemporal epidural approach to trigeminal neurinomas. Acta Neurochir (Wien) 130: 55–65, 1994.
3. Dolenc VV: Intracavernous carotid artery aneurysms. in: Spetzler RF, Carter LP (eds): Neurovascular Surgery. New York: McGraw-Hill, 1995, pp 659–673.
4. Dolenc VV: Transcranial epidural approach to pituitary tumors extending beyond the sella. Neurosurgery 41: 542–552, 1997.
5. Dolenc VV, Rogers L: Microsurgical Anatomy and Surgery of the Central Skull Base. Wien, Springer-Verlag, 2003.
EXTRADURAL ANTERIOR CLINOIDECTOMY， NEUROSURGERY VOLUME 61 | OPERATIVE NEUROSURGERY 2 | NOVEMBER 2007 | ONS185