Application Of Multimodal Fusion,Medial Wall Of Cavernous Sinus Resection And Multilayer Combined Skull Base Reconstruction In Functional Pituitary Adenoma

The pituitary gland is one of the most important endocrine glands in the human body.It is located in the pituitary fossa of the sellar turcica at the fossa of the middle cranial fossa and connected to the hypothalamus through the pituitary stalk and funnel.The pituitary gland could be divided into two major parts,pituitary in the front and neuropituitary in the back,and pituitary adenoma(PA)originated from the pituitary gland,which was a tumor of the neuroendocrine system.The incidence of PA ranks the third among intracranial tumors,second only to meningioma and glioma,accounting for about 10%of intracranial tumors and 8.2%-14.7%of the population,but its occurrence rate in autopsy is as high as 20%-30%.PA can be classified in several ways,among which,according to whether PA has hormone secretion function and corresponding clinical manifestations,it was divided into functional pituitary adenoma(FPA)and non-functional pituitary adenoma,with FPA accounting for about 63%-80%.According to the diameter of PA,it can be divided into microadenoma(<1cm),large adenoma(1-4cm)and giant adenoma(>4cm).In addition,pituitary adenoma could be divided into invasive pituitary adenoma(IPA)and non-invasive pituitary adenoma based on imaging classification,intraoperative findings and pathology.At present,there are two surgical approaches for PA,craniotomy and transnasal approach.Because the transnasal approach adopts the natural physiological gap of the human body,it has become the preferred surgical approach for the treatment of PA,with less tissue trauma and faster postoperative recovery.Neuroendoscopy,as an emerging surgical tool in recent years,has attracted more and more attention from surgeons.Compared with the traditional microscope,neuroendoscopy has the advantages of wide viewing angle,close observation,flexible operation,and easy to penetrate into the internal tissue space,etc.Endoscopic endonasal approach(EEA)to treat PA has become the main way of surgical treatment of PA.Since 2015,the digital medical,multimodal fusion technology is more and more application in neurosurgery,the emergence of new technology is the inevitable developing law of human science and technology,providing convenient at the same time,the performer also led us into a new field.In recent years we use pituitary MRI,paranasal sinus CT and brain CTA to creat a three dimensions image data fusion by 3D Slicer software.The preoperative reconstruction and evaluation of nasal cavity,sphenoid sinus septum and bone markers,sellar base,the relationship between tumor and ICA carried out.Acquiring surgical difficulties and key points were noted to provide preoperative technical and anatomical support for successful operation of FPA.In addition to the mass effect,the abnormal secretion of FPA is another major harm of tumors for patients.If hormones cannot be restored to normal after surgery,the symptoms caused by abnormal hormone levels before surgery cannot be alleviated.In order to achieve a complete endocrine cure,the sellar tumor,the lateral wall of the cavernous sinus close to the tumor and the tumor intruding into the cavernous sinus cavity should be completely resected.The resection of the medial wall of the cavernous sinus is a difficult operation,requiring high microscopic operation skills.By learning and improving the advanced experience at home and abroad,and studying the normal anatomy of the medial wall of cavernous sinus,our center has mastered the medial wall resection technology of cavernous sinus,and in the postoperative pathological examination,the detection rate of tumor cells in the removed medial wall of the cavernous sinus is very high.The postoperative cerebrospinal fluid leakage rate of FPAs is significantly high.Postoperative cerebrospinal fluid leakage can cause a series of complications such as meningitis,intracranial pneumatosis and so on.If cerebrospinal fluid leakage is prolonged for a long time,bed rest,indenture lumbar cistern drainage,antibiotics and anti-inflammatory are required after surgery,and some patients even need to have another operation.Since the invention of"Hadad-Bassagasteguy flap" in 2008,the incidence of cerebrospinal fluid rhinorrhea has been continuously decreasing,and "Rescue mucosal flap" and "Posterior mucosal flap" have been derived.The appearance of these different forms of mucosal flaps is to reconstruct the sellar bottom after nasal surgery and reduce the incidence of cerebrospinal fluid leakage and other postoperative complications.However,no matter the "Hadad-Bassagasteguy flap"." Rescue mucosal flap" or other similar nasal septum mucosal flaps,they are all made in different ways.Many treatment centers for PAs at home and abroad constantly put forward a variety of new skull base reconstruction programs.Since January 2019,according to the Kelly scale of intraoperative cerebrospinal fluid leakage in FPA,for Kelly grade 2 and grade 3 patients,we used a dural repair material,the fat,the sutured dura mater,a sellar floor bone flap(or a middle turbinate),a piece of autologous thigh fascia,a fat flap with dermal vascularity,a pedicled nasoseptal flap,and the absorbable dural sealing medical adhesive to reconstruct the skull base,and achieved good clinical results.Compared with the previous absorbable artificial dural,a sellar floor bone flap(or a middle turbinate),a piece of autologous thigh fascia and fat.nasal septum pedicled mucosal flap and the absorbable dural sealing medical adhesive to reconstruct skull base,this new method is significantly improved in the prevention of cerebrospinal fluid leakage and will not lead to postoperative nasal bleeding and other complications for Kelly grade 2 and grade 3 patients.In this study,EEA surgery for FPAs was used as the starting point.By dissecting the cadaveric head and becoming familiar with the surrounding structure of the medial wall of the cavernous sinus.From the application of multimodal medical images fusion,medial wall of cavernous sinus resection and multilayer combined skull base reconstruction,combined with the recent clinical work of our unit,we hope to provide beneficial help for this challenging clinical work of curing FPAs.Part 1 The microanatomy of the parasellar ligament,the inferior pituitary artery and the anchoring pattern of the medial wall of cavernous sinusObjectiveBy dissecting the cavernous sinus of the cadaveric head,the types of the lateral sellar ligaments fixing the medial wall of cavernous sinus,the arteries running through the ligaments and the anchorating mode of the medial wall of cavernous sinus were explored,providing anatomical basis for the resection of the medial wall of cavernous sinus in the EEA operation of FPA.MethodsFive cadaveric head specimens were selected,of which 2 were perfusion specimens(red latex was injected at the arterial end and blue latex was injected at the venous end)and 3 were general embalming specimens.The lateral walls of cavernous sinus on both sides were dissected under neuroendoscopy.ResultsCaroticoclinoid ligament(CCL)appeared in all cases.Superior parasellar ligament(SPL)appeared in 60%of all cases.Inferior parasellar ligament(IPL)appeared in 90%of all cases and posterior parasellar ligament(PPL)appeared in 50%of all cases.The incidence of inferior hypophyseal artery(IHA)is 100%and IHA is accompanied with PPL.The lateral wall of cavernous sinus is connected to ICA or other lateral walls of cavernous sinus by two anchoring methods.ConclusionCCL is the ligament with the highest occurrence rate among all the ligaments anchored to the medial wall of the cavernous sinus.The medial wall of the cavernous sinus is mainly anchored to ICA or other lateral walls of the cavernous sinus independently through various ligaments.To complete resection of the medial wall of the cavernous sinus,it is necessary to gradually remove the lateral saddle ligament and IHA on the basis of being familiar with the surrounding lateral wall of the cavernous sinus.Part 2 Multimodal fusion,lateral cavernous sinus resection and multilayer combined skull base reconstruction in endoscopic transnasal surgery for functional pituitary adenomaObjectiveTo explore new preoperative and intraoperative plans to reduce the risk of surgical injury,improve the postoperative biochemical cure rate and reduce the incidence of postoperative complications in EEA surgery with FPA.MethodsA total of 60 patients who qualified for inclusion and received EEA treatment for FPA in our unit from January 2019 to June 2021 were selected.Preoperative 3D Slicer software was used for fusion reconstruction of the three images data of sellar region MRI,cranial CTA,and sinus CT.The medial wall of cavernous sinus directly in contact with the tumor was resected.After surgery,a new multi-layer combined skull base reconstruction scheme was adopted for Kelly grade 2 and 3 patients according to the Kelly grade of cerebrospinal fluid leakage.The surgical video was reviewed to compare whether the intraoperative situation was consistent with the preoperative fusion reconstruction image,the detection rate of tumor cells in the medial wall of cavernous sinus and the postoperative biochemical cure rate were recorded,and the incidence of postoperative cerebrospinal fluid leakage was calculated.ResultsAll the 60 patients with FPA successfully completed the operation and were followed up for 18 months,and no cases were lost to follow-up.The anatomical structure reconstructed by multimodal fusion before surgery was confirmed by operation.Sixty-two sides of the lateral wall of cavernous sinus were removed during the operation.The tumor cell detection rate was 86.7%(52/60),and the postoperative biochemical cure rate of abnormal hormone was 85%(51/60).With the new multilayer combined skull base reconstruction protocol,the incidence of cerebrospinal fluid leakage was 3.3%.ConclusionPreoperative multimodal fusion reconstruction can actually preview the intraoperative situation.The detection rate of tumor cells in the lateral wall of cavernous sinus was high and the curative effect of abnormal hormone was obvious.The incidence of cerebrospinal fluid leakage was lower with the new multilayer combined reconstruction of skull base.Part 3 Significance of multimodal fusion,lateral cavernous sinus resection and multilayer combined skull base reconstruction in the treatment of functional pituitary adenomaObjectiveTo clarify the significance of multimodal fusion reconstruction,lateral lateral cavernous sinus resection and new multilayer combined skull base reconstruction in endoscopic transnasal surgery for functional pituitary adenoma.MethodsSixty patients with FPA who received EEA treatment in our unit from January 2019 to June 2021 were selected as the experimental group.3D Slicer software was used for preoperative fusion reconstruction of MRI,cranium CTA,and CT of sinuses of the sellar region for these 60 patients,and the medial wall of cavernous sinus directly in contact with the tumor was removed during the operation.After surgery,the patients were followed up for 18 months using a new multi-layer combined skull base reconstruction regimen based on the Kelly grade of CSF leakage.At the same time,the relevant data of 61 patients with FPA treated by the same medical team from January 2017 to December 2018 with the same enrollment conditions as the experimental group were retrospectively analyzed and set as the control group.All the 61 patients underwent EEA surgery.However,the 61 patients were also followed up for 18 months without preoperative multimodal medical image fusion,intraoperative resection of the medial cavernous sinus,and traditional skull base reconstruction after surgery.The operation time,ICA injury rate,intraoperative cerebrospinal fluid leakage rate,tumor total resection rate,postoperative hormone cure rate,postoperative intracranial infection rate,postoperative cerebrospinal fluid leakage rate,postoperative nasal septum pedicle mucosal flap healing rate,postoperative nasal bleeding rate,postoperative hospital stay of patients,and postoperative tumor recurrence rate 18 months after surgery were compared between the two groups.ResultsAll 121 patients with FPA successfully completed the operation and were followed up for 18 months,and no case was lost to follow-up.There was no significant difference in preoperative basic information between the two groups(p>0.05).In all items compared between the two groups,there were no statistical differences in the incidence of intraoperative cerebrospinal fluid leakage,total tumor resection rate and postoperative nasal bleeding rate(p>0.05).There were statistical differences in the operation time,the incidence of ICA injury during the operation,the healing rate of nasal septum pedicled mucosa flap after the operation,the length of postoperative hospital stay,and the recurrence rate of tumor 18 months after the operation(p<0.05).There were statistically significant differences in the postoperative hormone cure rate,the incidence of postoperative intracranial infection and the incidence of postoperative cerebrospinal fluid leakage(p<0.01).ConclusionFor patients with FPA treated by EEA,preoperative multi-modal medical image fusion,surgical planning,intraoperative resection of the medial wall of cavernous sinus directly in contact with the tumor,and the new multi-layer combined reconstruction of skull base after surgery can significantly improve the postoperative hormone levels,reduce the incidence of postoperative cerebrospinal fluid leakage and intracranial infection.It can shorten the operation time,avoid ICA injury,improve the healing rate of nasal septum pedicled mucosa flap,reduce the length of postoperative hospital stay and prevent tumor recurrence.There was no significant help for the incidence of intraoperative cerebrospinal fluid leakage,whether the tumor was completely removed or not,and whether there was postoperative nasal bleeding.