The Anatomical Study Of Endoscopic Endonasal Approach To Lateral Opticocarotid Recess Region

Objective: To investigate the anatomical characteristics of the periarea of the lateral opticocarotid recess via the endoscopic endonasal transsphenoidal approach,and provide anatomical reference for clinical operation.Methods: 10 cases(20 sides)of adult cadaver heads fixed by formalin were used to research the important structures in the surrounding area of the LOCR by transnasal endoscopic endonasal transsphenoidal approach,and 50 cases of brain 3D CT images were selected.Anatomical images were collected by Karl Storz endoscopy system and image data was obtained by image measurement software.During the anatomic process,we search for the anatomic characteristics of the area around LOCR.The tumor around the LOCR region were resected via extended endoscopic endonasal transsphenoidal approach on 3 patients(pituitary adenoma,Sellar floor cavernous sinus malignant tumor,Sellar special infection,adenoid cystic carcinoma),the perioperative tissue lesions resected completely or mostly,then the skull base was reconstructed by sandwich structure consisting Of artificial dura mater and nasal septum mucosal flap.Eventually,the postoperstive MRI was applied.Results: According to the characteristics of LOCR region,anatomic markers include LOCR,optic canal protuberance,internal carotid artery protuberance,optic column and supraorbital fissure.The adjoining region of LOCR can be divided into five regions: the medial,the lateral,the superior,the lower and the anterior clinoid process area.The medial region border include the parasaddle internal.Passing over the carotid artery and the cranial canal of the optic nerve,we can reach the optic chiasma,the anterior and inferior cavernous sinus,and the pituitary gland.Adjacenting to the medial wall of the supraorbital fissure is the lateral region.The superior region is adjacent to optic canal protuberance,extending to the sphenoid plateau.The inferior region is near the lateral cavernous sinus area.Through the anterior clinoid process region,we can get the anterior clinoid process.The distance between two sides of LOCR was(15.3 ±1.8)mm,the range was 13.5 ~ 17.1 mm,which between two sides of MOCR was(10.3 ±1.5)mm,the range was 8.8±11.8mm.The horizontal diameter of LOCR was(2.3 ±0.84)mm,in front of Sellar tubercle for 10 mm,the transverse diameter was(24.5±2.35)mm.The distance between the outer edge of LOCR and the orbital orifice was(8.6 ±3.2)mm.Between the internal carotid,the distance was(15.8 ±2.8)mm.According to the image measurement results,the medial distance between bilateral LOCR was(13.34±3.392)mm,the distance between bilateral LOCR was(15.33 ±4.055)mm,the diameter of unilateral OCR was(2.370 ±0.8534)mm,and the length of anterior clinoid process was(9.61±1.117)mm.The results of the measurement of the related structures in the endoscopic anatomic process were basically consistent with the image data.Through the endoscopicanatomy of the LOCR,we can get C4?C5?C6?C7 internal carotid artery.The location of the anterior bed process can be found by grinding the bone in LOCR area under the endoscope.The process space can be obtained by further grinding the anterior bed process,which can provide a reference path for the treatment of the peripheral lesion of the anterior bed.The 3patients with lesions around LOCR could be excised to the maximum extent and the result of operation is satisfactory.During excision one case happened skull base defect,we used artificial dura mater and nasal septal mucosal flap to repair the skull base.The patient recovered well without cerebrospinal fluid rhinorrhea.Conclusion: Mastering the anatomical markers of the LOCR region is of great significance in the treatment of the lesions of the skull base in the LOCR area.It is safe and effective to solve the lesions of the skull base in the LOCR area according to the anatomical division of LOCR under endoscope.