The Study Of Applied Anatomy And Clinical Significance Of The Safety Abrading Range Of Cranial Nasal Communication Area In The Microsurgery Of Cranial Nasal Tumors

Cranial nasal communication area is a plate with two sides. Outside theskull are nasal cavity, parannasal sinuses, eyes and pterygopalatine fossa.Anterior skull base with many complex nerves and blood vessels include opticcanal, anterior|posterior ethmoidal foramen and superior orbital fissure. Insidethe skull are frontal lobe, the olfactory nerve, olfactory bulb and olfactory sacand adjacent to optic chiasm pituitary, cavernous sinus, internal carotid artery,temporal lobe. Cranial-nasal tumor locates in a dangerous area inneurosurgical operation because of its deep location, complex anatomicalrelationships and involvement of the above-mentioned three structures. Thepresent study aims at exploring the safety abrading range of cranial nasalcommunication area for clinical application. We made comparative analysis ofimaging and performed imaging observation and safety abrading rangemeasurement, which provided anatomy basis for safe, complete andeffective cranial-nasal tumor resection and was in favor of making detailedoperation program.The first part The Study of Microsurgical anatomy andsafety abrading range of cranial nasal communication areaObjective:To explore the microscopic anatomy of cranial nasalcommunication area and anatomic landmark of cranial-nasal tumor resectionand clear the safety abrading range.Method:We take the double frontal coronal incision,observe the anteriorskull base bony structure, exposure range, ethmoid bone, sphenoid bone andoptic canal and measure the distance from crista galli leading edge to medial orbital wall and chiasmatic sulcus, distance from optic nerve canal orbitalaperture and optic nerve intracranial mouth to midline, distance from internalcarotid artery segment clinoid to midline, at last calculate the abrading bonearea. Dry skull bases was studied by direct measurement and observation. Allthe measurement data are presented as the mean±standard deviation (SD)Results:1.The microscopic anatomy of cranial nasal communication areaLamina cribiosa and sphenoid platform are between chiasmatic sulcusand frontal sinuses in anterior cranial fossa center. Both sides are the orbitalroof. Inside the skull are frontal lobe, the olfactory nerve, olfactory bulb andolfactory sac and adjacent to optic chiasm pituitary, cavernous sinus, internalcarotid artery, temporal lobe. Outside the skull are nasal cavity, parannasalsinuses, eyes and pterygopalatine fossa. The important anatomic landmark ofcranial-nasal tumor resection include: crista galli, lamina papyracea, opticcanal and the optic chiasm ditch.2.The measurement results of safety range in cranial nasalcommunication areaDistance from chiasmatic sulcus leading edge to crista galli leadingedge:(38.951.49mm);Distance from crista galli leading edge to left and right medial orbitalwall,respectively:(13.501.15mm）（13.551.20mm）;Length of left and right optic canal,respectively:(10.70.92m）（10.940.85mm）;The agle of the midline and left and right optic canal, respectively:（39.302.56°）(39.214.01°);Distance from left and right optic nerve canal orbital aperture to midline,respectively:(13.971.19mm）（13.581.53mm）;Distance from left and right optic nerve intracranial mouthtomidline,respectively:（8.390.72mm）（8.410.69mm）;Distance from left and right internal carotid artery segment clinoid tomidline, respectively:（7.060.71mm）（7.020.72mm）; Abrading bone area of cranial nasal communication area（:10.051.00cm2）.Conclusions:1. The anatomical landmarks of cranial-nasal tumor resection includecrista galli, lamina papyracea, optic canal and chiasmatic sulcus.2. The safety abrading range in the cranial-nasal tumor resection: fromboth sides of crista galli to lamina papyracea, backwards to chiasmatic sulcusfront, along the anterior skull base midline backwards and outwards to opticnerve canal orbital aperture, optic canal and optic canal craniooral.3. Microscopic anatomy provides important anatomic structure of cranialnasal communication area, safety abrading range index and practical value forsafety, complete and effective cranial-nasal tumor resection. The second part Imaging measurement and analysis of safetyabrading range of cranial nasal communication areaObjective:To clear objective and true pathological anatomical features ofcranial-nasal tumor patients, measure safety abrading range of cranial nasalcommunication area and provide accurate, individualized anatomical basis forclinical cranial-nasal tumor resection.Method:We obtained three anatomical parameters of imagingmeasurement of50cranial-nasal tumor patients and50normal control safetyabrading range of cranial nasal communication area by Medviwer software andanatomic measurement of20above-mentioned skull specimens by slidecalliper rule and compass. Independent-samples T tests was used to analyze. Pvalue of less than0.05was considered significant, P value of less than0.01was considered statistically significant difference, P value between0.05and0.8could not be determined whether it is significant, P value of more than0.8 was considered no difference（degree of confidence＞80%）. All analyses wereperformed using SPSS13.0.Results：1.Imaging measured values of cranial-nasal tumor patients.Distance from chiasmatic sulcus leading edge to crista galli leadingedge:39.031.42mm.Distance from crista galli leading edge to left and right medial orbitalwall, respectively:14.520.86mm,14.440.88mm.Length of left and right optic canal,respectively:10.650.95mm,11.021.09mm.Angle of the midline and left and right optic canal, respectively:41.292.95°,41.352.67°.Distance from left and right optic nerve canal orbital aperture to midline,respectively:14.670.76mm,14.440.98mm.Distance from left and right optic nerve intracranial mouth to midline,respectively:8.481.02mm,8.470.94mm.Distance from left and right internal carotid artery clinoid segment tomidline, respectively:7.081.01mm,7.101.00mm.Abrading bone area of cranial nasal communication area:10.150.89cm2. two-two comparative analysis results among the three groups.2.1No statistical significance were obtained between anatomic measure-mentand imagine measurement in normal controls (P>0.8).2.2the position of medial orbital wall, optic canal angle, orbital mouth wereconsidered statistical difference in two comparisons of anatomic measurementand imaging measurement of cranial-nasal tumor patients and imagingmeasurement of cranial-nasal tumor patients and normal controls(P <0.05),The other measurement parameters difference could not be determinedwhether it is significant.Conclusions：1. Imaging measurement of skull base CT and enhanced CT scan data byMedviwer3.0can objectively reflect anatomic relationship in cranial nasal communication area.2.There is statistical difference in anatomic structure of surgical areabetween cranial-nasal tumor patients and normal controls, especially theposition of medial orbital wall, optic canal angle, orbital mouth.3. Imaging measurement parameter range of a large number of samples isapproximate to the population range.4. Imagining observation and measurement of safety abrading rangebefore cranial-nasal tumor resection, which reflects the patients anatomiccharacteristics more accurately, provide practical value for improvingcomplete removal rate and surgical safety. The third part The clinical application of Imaginingmeasurement of safety abrading range before cranial-nasaltumor resection and reconstruction of skull base.Objective:To explore the clinical application value of imaginemeasurement to complete, safe and effective cranial-nasal tumor resection andstudy the effect of pedicled flaps of percanial and aponeurotica galesreparation and taking “sandwich” to reconstruct skull base.Method:1.19cranial-nasal tumor patients underwent skull base CT and enhancedCT scan and were measured the maximum safety abrading range and cleartumor specific location, range, blood supplication and relation to the basiscrania,which could guide the surgeon make the detailed and individualizedoperation scheme.2. We take surgery approach to skull base via double frontal to removecranial-nasal tumor, operating procedures as follow:2.1Separate and protect nasopharyngeal mucosa. 2.2Manifest anterior cranial fossa.2.3Remove the tumor and anterior skull base.2.4Reconstruct skull base by using pedicled flaps of percanial andaponeurotica gales or “sandwich”.Results: Among the19cranial-nasal tumor patients including12caseswith benign tumor and7cases with malignant tumor,17cases were to totallyremoved and2cases were subtotally removed. Four patients include3cases offrontal psychiatric symptoms and1case of infection. Others have goodrecovery without death or cerebrospinal fluid fistulous. Among the16patientswho were followed up for2to3years,1nasopharyngeal carcinoma patientsrelapsed after2years with systemic metastasis and died of collapse;1olfactory neuroblastoma relapsed after3years without treatment and died ofintracranial hypertension; the other14cases without relapse could deal withevery life and work normally.Conclusions:1.Imagining observation and measurement of safety abrading rangebefore cranial-nasal tumor resection by Medviwer3.0guide the surgeon tomake up detailed and individualized surgery program, so as to improvecomplete removal rate and surgical safety.2.The choice of surgical approach to skull base via double frontal, skilledmicrosurgical technique, advanced surgical apparatus can make cranial-nasaltumor resection perfect effect.3.We take “sandwich” to reconstruct skull base, the specific proceduresare as follows: first, fix the flaps of percanial and aponeurotica gales bybiological glue in the bottom; second, use shaping titanium plate as bonereparation; at last, suture the broken dural with artificial dural mater tightly,which can prevent cerebrospinal fluid rhinorrhea effectively.4.On the condition of effective skull base reconstruction, cranial-nasal tumor can amplify dural and abrading bone arrange properly, so as to removethe tumor maximally, reduce the relapse and promise long-term effect.