A Study Of Applied Anatomy Of Resecting Pituitary Adenomas Through Single Nostril Transsphenoidal Approach

Objective: The purpose of this research is to supply basic microsurgical anatomy data by the way of dealing with adult skull examples. For the convenience of clinical work and improvement of surgical operation method, protecting vital structure ,improve the safety of the surgical operation, extend the orientation of operation and reduce operation complications in sellar region through single nostril transsphenoidal approach .Method: 20 dry bones of skull, we deal with 10 examples (20 sides) adult dry skull examples which have fixed, as we imitate the single nostril transsphenoidal approach to sellar region and examine the vital structures which are important in operation.Adult dry skull examples which have fixed injected from the vertebralis artery and internal carotid artery by the Urokinase, the clips blood vessels preparing after flushing the blood vessel ,adding press inject the vertebralis artery and internal carotid artery by the urine aqua, the clips blood vessels. Place to make artery to dry to combine well to restores to the best after 48 hours to organize originally possessed appearance.Make use of the skull examples, proceed operation with the right side and the left side. Place the skull examples on the felid, put the Hardy speculum into the nasal fossa proper along the nasal septum, push away the middle nasal concha, remove the nasal septum from the crista sphenoidalis. Among the recessus spheno-ethmoidalis, superior nasal concha, nasal septum, find the ostium of sphenoidal sinus, open the anterior wall of the sphenoid sinus from the inferior pole of the ostium of sphenoidal sinus, expose the sellar floor with Kerrsion pliers ,remove the dura mater encephali of sellar floor and discover the pituitary, resect the pituitary, open the diaphragma sellar, at last discover the cavernous sinus, carotid artery and optic canal.Measure the average distances from the anterior nasal spina to the ostia of sphenoidal sinus, sellar base, centre of dorsum, entrances of internal carotid artery and optic canal to cranial cavity respectively; also the angles of the bottom of nasal cavity with the aforesaid structures.Measure the anteroposterior distance of the ostium of sphenoid sinus,the distances from its left to its right,the distances from its top to its bottom; the average distances from the ostium of sphenoid sinus to the median line, carotid artery canal, optic canal.Observe the pituitary gland, the pituitary fossa and the cavernous sinus.At last, separate all the skull examples along the median sagittal.Results:1 The microanatomy of single nostril transsphenoidal approach 1.1 The average distances from the anterior nasal spine to the ostium of sphenoidal sinus, sellar base, centre of dorsum sellae, entrance of internal carotid artery and optic canal to cranial cavity are 57.8±4.9mm, 72.0±2.3mm, 79.0±4.6mm 69.0±4.8mm, 68.7±4.8mm respectively.The angles of the bottom of nasal cavity with the aforesaid structures are 31.5±2.7°, 31.2±4.9°, 35.4±3.9°, 31.7±4.3°38.0±5.2°.1.2 The ostium of sphenoidal sinus:the distance from its top to its bottom: 3.5±1.5mm(1.2～6.6mm).the distance from its left to its right: 1.5±0.5mm(0.8～2.6mm). the average distance from the top of ostium of sphenoid sinus to the median line: 3.4±1.0mm(1.3～4.8mm).the average distance from the bottom of ostium of sphenoid sinus to the median line: 3.7±1.0mm(1.9～7.2mm).the average distance from the ostium of sphenoid sinus to the top of recessus spheno-ethmoidal: 7.3±2.4mm(2.0～18.0mm).1.3 The average distance from the ostium of sphenoid sinus to the sellar region:The average distances from the ostium of sphenoidal sinus to the optic nerve, carotid artery , sellar base,centre of tuberculum sellae, centre of dorsum sellae are 10.6±1.8(7.8～21.4)mm, 12.7±1.8(9.3～17.4)mm, 16.2±3.7(11.0～24.0)mm, 14.8±3.0(7.1～15.8)mm, 22.8±3.2(17.8～20.4)mm respectively. 2 Pituitary fossa: The anteroposterior distance of the pituitary fossa,the distances from its left to its right,the distances from its top to its bottom are 10.1±0.9mm(7.0～12.6 mm), 13.8±1.8mm(8.9～20.1 mm) , 6.7±1.3 mm (3.5～9.1 mm).The anteroposterior distance of the pituitary gland,the distances from its left to its right,the distances from its top to its bottom are10.1±1.6mm(6.0~12.8),14.3±2.0mm(10.9~19.8), 6.5±1.4mm (3.3～9.4mm).3 Pituitary gland and its surrounding structuresthe length between two cavernous: 13.2±1.36mm(9.1～19mm). the length between the inner borders of carotid artery and the outer borders of pituitary gland: 3.8±2.21mm(2.3～7.1mm).Conclusion: 1 The structures of sellar region can be observed well by microscope via the single nostril transsphenoidal approach. Contrary to the classical surgery, it can reduce a series of injury and complications.2 The ostium of sphenoidal sinus is a very important anatomical landmarks in the single nostril transsphenoidal approach surgery; The angle of the bottom of nasal cavity with the ostium of sphenoidal sinus is 31.5°(∠AOD), The average distances from the anterior nasal spine to the ostium of sphenoidal sinus is 57.8mm along the nasal septum and the anterior wall of the sphenoid sinus is opened from the inferior pole of the ostium of sphenoidal sinus strictly along the middle-line. 3 The optic nerve prominence and the carotid artery prominence exit on the outer wall of the sphenoid sinus , the length between them and the median line are 5.60±2.10mm,5.40±1.52mm,so the anterior wall of the sphenoid sinus is exposed within 10mm.4 Because the length between two cavernous sinus is 13.2±1.36mm(10.1～19mm),the sellar floor is exposed within 9.1mm to avoid injurying the cavernous sinus and its important structures.