title: Measurement of Critical Structures around Paraclinoidal Area : A Cadaveric Morphometric Study.
abstract: OBJECTIVE
  Although removal of the anterior clinoid process (ACP) is essential surgical technique, studies about quantitative measurements of the space broadening by the anterior clinoidectomy are rare. The purposes of this study are to investigate the dimension of the ACP, to quantify the improved exposure of the parasellar space after extradural anterior clinoidectomy and to measure the correlation of each structure around the paraclinoidal area.
  
  
  METHODS
  Eleven formalin-fixed Korean adult cadaveric heads were used and frontotemporal craniotomies were done bilaterally. The length of C6 segment of the internal carotid artery on its lateral and medial side and optic nerve length were checked before and after anterior clinoidectomy. The basal width and height of the ACP were measured. The relationships among the paraclinoidal structures were assessed. The origin and projection of the ophthalmic artery (OA) were investigated.
  
  
  RESULTS
  The mean values of intradural basal width and height of the ACP were 10.82 mm and 7.61 mm respectively. The mean length of the C6 lateral and medial side increased 49%. The mean length of optic nerve increased 97%. At the parasellar area, the lengths from the optic strut to the falciform liament, distal dural ring, origin of OA were 6.69 mm, 9.36 mm and 5.99 mm, respectively. The distance between CN III and IV was 11.06 mm.
  
  
  CONCLUSIONS
  With the removal of ACP, exposure of the C6 segments and optic nerve can expand 49% and 97%, respectively. This technique should be among a surgeon's essential skills for treating lesions around the parasellar area.
authors.affiliation: Department of Neurosurgery, College of Medicine, Dong-A University, Busan, Korea.
authors.forename: Hyun-Woo
authors.initials: HW
authors.lastname: Lee
authors.forename: Hyun-Seok
authors.initials: HS
authors.lastname: Park
authors.forename: Ki-Soo
authors.initials: KS
authors.lastname: Yoo
authors.forename: Ki-Uk
authors.initials: KU
authors.lastname: Kim
authors.forename: Young-Jin
authors.initials: YJ
authors.lastname: Song
keywords: Anterior clinoid process; Extradural anterior clinoidectomy; Ophthalmic segment; Optic strut
references.citation: J Clin Neurosci. 2004 Apr;11(3):283-7
references.pmid: 14975418
references.citation: Neurosurgery. 2003 Jul;53(1):162-6; discussion 166-7
references.pmid: 12823885
references.citation: Yonsei Med J. 1997 Jun;38(3):151-4
references.pmid: 9259614
references.citation: Neurosurgery. 2009 Mar;64(3 Suppl):ons96-105; discussion ons105-6
references.pmid: 19240577
references.citation: Neurosurgery. 1990 Jun;26(6):903-32
references.pmid: 2362670
references.citation: Neurosurgery. 1996 Mar;38(3):425-32; discussion 432-3
references.pmid: 8837792
references.citation: J Neurosurg. 1981 Oct;55(4):560-74
references.pmid: 7277004
references.citation: Acta Neurochir (Wien). 2006 Sep;148(9):971-5; discussion 975-6
references.pmid: 16917665
references.citation: World Neurosurg. 2012 May-Jun;77(5-6):698-703
references.pmid: 22120307
references.citation: Clin Anat. 2005 Jan;18(1):3-9
references.pmid: 15597376
references.citation: Neurosurgery. 2006 Oct;59(4 Suppl 2):ONS253-62; discussion ONS262
references.pmid: 17041495
references.citation: Surg Neurol Int. 2011;2:140
references.pmid: 22059135
references.citation: Acta Neurochir (Wien). 2004 May;146(5):505-9
references.pmid: 15118888
references.citation: Neurosurg Rev. 2006 Jul;29(3):213-8
references.pmid: 16775743
references.citation: J Neurosurg. 1985 May;62(5):667-72
references.pmid: 3989589
references.citation: Acta Neurochir (Wien). 1997;139(4):361-5
references.pmid: 9202779
references.citation: Skull Base. 2010 Jul;20(4):229-36
references.pmid: 21311615
references.citation: J Neurosurg. 1997 Oct;87(4):636-42
references.pmid: 9322855
references.citation: Neurosurgery. 2007 Nov;61(5 Suppl 2):179-85; discussion 185-6
references.pmid: 18091231
references.citation: J Neurosurg. 2005 May;102(5):945-50
references.pmid: 15926728