This paper describes an extradural approach to the lateral sellar compartment (LSC, cavernous sinus), which represents a refinement of the original work performed on this topic by Parkinson, Dolenc, and Hakuba, and other enthusiastic neurosurgeons. This detailed description of the extradural approach is based on the dissection of 30 cadaver specimens and surgical experience of 110 LSC lesions. The extradural approach is based on the developmental anatomy of the LSC, and provides: (1) complete exposure of the entire LSC; (2) excellent control of the intracavernous carotid artery; (3) easier identification and less injury of the cranial nerves; (4) reduced brain damage with limited extradural retraction; (5) preserving the Sylvian vein and the sphenoparietal sinus; (6) minimal intradural blood spillage; (7) shorter operative time; (8) physiological reconstruction of the lateral wall to prevent CSF leakage; and (9) access to the contralateral LSC. As the LSC is an extradural space, the extradural approach may be safely employed to access lesions involving the LSC.
Cavernous Sinus/surgery* ; Cavernous Sinus/anatomy & histology ; Craniotomy ; Dissection ; Human ; Microsurgery

OBJECTIVEThe anatomic features of transsphenoidal approach are reviewed, focusing on the microsurgical anatomy of suprasellar and parasellar structures. Pertinent microsurgical anatomy is described for neurosurgeons to successfully extend a standard transsphenoidal approach for treatment of lesions including the region of the tuberculum sellae, planum sphenoidale, supradiaphragmatic intradural space, and medial cavernous sinus.

METHODS15 specimens (30 sides) from formalin fixed cadaveric heads and 20 adult dry skulls (40 sides) were observed. According to the need for the extend transsphenoidal approach, the sellar and parasellar region: the planum sphenoidale and the supradiaphragmatic area, medial part of cavernous sinus were studied. Special emphases were put on the relation of the cranial nerve and blood vessel structures surrounding the sellar. Meanwhile, we made the cast specimen of the blood vessel and studied the structure character of the internal carotid artery in the cavernous sinus.

RESULTSPosterior ethmoidal could be exit as para or suprasphenoidal ethmoidal air cell. It will be important for extending the transsphenoidal approach. The mean distance between two optic canal is 15.7 +/- 3.2 mm (11.0 - 18.0 mm), the distance of internal carotid artery at tuberculum cellae level is 13.9 +/- 3.8 mm (10.0 - 17.0 mm), the mean distance between tuberculum cellae and the posterior rim of cribriform plate is 23.3 +/- 3.2 mm, the included angle between sagittal plane and optic canal is 36.3 degrees +/- 1.6 degrees , with the anatomy research data give the clue that the bone window should be made as the shape of "[see text]".

CONCLUSIONSExpending transsphenoidal approach is suitable for medium and small lesions growing along the centre line which expand to para sellar, anterior sellar and sphenoid platform. That hypophysis has close relation with internal carotid artery during expending transsphenoidal approach to cavernous sinus increase the risk of operation. The carotid artery and abducent nerve are the easiest structures to be damaged during the operation.

Adult ; Cadaver ; Cavernous Sinus ; anatomy & histology ; surgery ; Humans ; Sphenoid Bone ; anatomy & histology ; surgery ; Sphenoid Sinus ; anatomy & histology ; surgery

The anterior clinoid process and the optic strut are often removed during operation on the anterior part of the cavernous sinus. Therefore it is important for neurosurgeons to verify their dimensions and variations. The purpose of this study was to investigate the dimension and the variation of the anterior clinoid process and to describe the locational variation of the optic strut. Seventy-three skulls of Korean adults were used. The average length, basal width and thickness of the anterior clinoid process were 9.18 +/- 1.55, 9.63 +/- 1.49 and 5.32 +/- 1.07 mm, respectively. The average thickness of the optic strut was 2.9 +/- 1.15 mm and it was commonly attached to anterior two-fifths of the anterior clinoid process. The complete caroticoclinoid canal was observed in 4.1%, however it was incomplete in 11.6%. The incidence of a caroticoclinoid canal in Koreans was relatively low compared with other races.
Adult ; Cadaver ; Cavernous Sinus/anatomy & histology* ; Human ; Korea/ethnology ; Mongoloid Race* ; Sphenoid Bone/anatomy & histology*

OBJECTIVETo study the anatomical and morphological characteristics of the venous spaces involved in surgery via transsphenoidal approach to the cavernous sinus (CS).

METHODSTen fixed cadaver heads (six male, four female) with red and blue latex injected in the arteries and veins, respectively, were used to perform the transsphenoidal approach. The anterior wall of the sphenoidal sinus and the floor of sellar turcica were opened as much as possible to expose the dura mater at the sellar floor and the inferior wall of CS, and the location of the anterior and inferior intercavernous sinuses were observed carefully. All the spaces of CS were observed and measured. According to the observations, the venous spaces available for operation were identified and analyzed.

RESULTSIn all the cadaver heads, 4 anterior and 5 inferior intercavernous sinuses were found, with the former locating below the optic protuberance, while the latter situated at the turn of the sellar protuberance at the clival indentation. CS was subdivided into medial space, inferolateral space, and dorsolateral space.

CONCLUSIONSIn transsphenoidal approach, opening of anterior and inferior intercavernous sinus is liable to result in intra- and postoperative venous bleeding, and understanding of the location of the intercavernous sinus and appropriate utilization of these CS may help reduce intraoperative vascular and nerve injury.

Cadaver ; Cavernous Sinus ; anatomy & histology ; surgery ; Female ; Humans ; Male ; Models, Anatomic ; Neurosurgical Procedures ; Sphenoid Sinus ; anatomy & histology ; blood supply ; surgery

OBJECTIVE: To investigate the anatomical relationship among optic nerve, posterior ethmoid sinus and ophthalmic artery to further provide surgical instruction for endoscopic transsphenoidal optic nerve decompression. METHOD: Messerklinger technique was adopted in eight cases of adult cadaveric head to expose the posterior ethmoid sinus and sphenoid sinus. The optic-carotid recess and optic canal were identified. The adjacent structure of optic canal was observed. After removal of the bony wall of optic canal, the relationship between the optic nerve and the ophthalmic artery was disrupted. RESULT: the optic-carotid recess was observed in all specimens. The occurrence of optic nerve prominence was 62%. Three patterns of the syntropy of optic nerve were observed. Optic nerve was border by posterior ethmoid sinus anteriorly and sphenoid sinus posteriorly in 8 cases (50%), by sphenoid sinus in 5 (31%), and by posterior ethmoid sinus in 3 (19%). At the cranial end, The ophthalmic artery was observed, 9 (56%) inferior-medially, 4 (25%) inferiorly and 3 (19%) inferior-laterally relative to optic nerve. At the ophthalmic end, the artery was observed 3 (19%) inferiorly and 13 (81%) inferior-laterally relative to optic nerve. CONCLUSION The optic-carotid recess can be regarded as the first landmark. The ophthalmic artery injury should be avoided with regard to its relationship with optic nerve during endoscopic decompression surgery.
Adult ; Cavernous Sinus ; anatomy & histology ; Decompression, Surgical ; methods ; Endoscopy ; Ethmoid Sinus ; anatomy & histology ; Humans ; Ophthalmic Artery ; anatomy & histology ; Optic Nerve ; anatomy & histology ; surgery ; Orbit ; anatomy & histology ; Sphenoid Sinus ; anatomy & histology ; surgery

For the surgical approach to lesions around the cavernous sinus (CS), triangular spaces around CS have been devised. However, educational materials for learning the triangles were insufficient. The purpose of this study is to present educational materials about the triangles, consisting of a schematic diagram and 3-dimensional (3D) models with sectioned images. To achieve the purposes, other studies were analyzed to establish new definitions and names of the triangular spaces. Learning materials including schematic diagrams and 3D models with cadaver's sectioned images were manufactured. Our new definition was attested by observing the sectioned images and 3D models. The triangles and the four representative surgical approaches were stereoscopically indicated on the 3D models. All materials of this study were put into Portable Document Format file and were distributed freely at our homepage (anatomy.dongguk.ac.kr/triangles). By using our schematic diagram and the 3D models with sectioned images, ten triangles and the related structures could be understood and observed accurately. We expect that our data will contribute to anatomy education, surgery training, and radiologic understanding of the triangles and related structures.
Anatomy, Cross-Sectional ; Carotid Artery, Internal ; Cavernous Sinus* ; Education ; Imaging, Three-Dimensional ; Learning ; Microsurgery ; Neuroanatomy