Sphenoid wing meningioma: Microsurgery and clinical outcomes in vietduc hospital – Do Van Dung

Journal of military pharmaco-medicine n o 3-2018 140 SPHENOID WING MENINGIOMA: MICROSURGERY AND CLINICAL OUTCOMES IN VIETDUC HOSPITAL Do Van Dung*; Dong Van He**; Vu Van Hoe*** SUMMARY Objectives: Sphenoid wing meningiomas (SWMs) are skull base tumors that are associated with significant morbidity and mortality, especially in medial sphenoid wing meningiomas (MSWMs) as their anatomic proximity to many critical neurological and vascular structures. This study aimed to evaluate the clinical outcome and SWM surgical resection. Subjects and methods: A descriptive and interventional study was conducted on 60 SWMs which were operated from 2013 to 2015 at Vietduc Hospital. Result and conclusion: According to Simpson’s classification, tumor resection grade I and II accounted for 60%, good outcome (KPS 80-100) achieved in 65% of the patients, average outcome: 35%, mortality 5%. Visual improved in 23.81%. Cranial nervous outcome: III 65.39%, V: 29.2%, IV: 57.14%, VI: 53.85%. Recurrence 15.4%, follow-up period 14.5 months. * Keywords: Sphenoid wing meningiomas; Microsurgery; Clinical outcome. INTRODUCTION Sphenoid wing meningiomas (SWMs) are in the skull base tumors, accounting for approximately 15 - 20% of intracranial meningiomas. It was divided into three groups on the basis of preoperative radiology findings: lateral, middle, medial. Among them, there are some parts related to the medial, such as internal carotid, cavernous sinus and cranial nervous II, III, IV, V, VI. As a result, how to resect the whole tumor but still preserve the relevant components to improve the cranial nervous outcome and the quality of life after operation is an emerging issue that neurosurgeons are faced with. However, the results vary from center to center due to many factors. Some recent reports also inform that the rate of total tumors resection ranges from 59 to 86.7%, mortality remains as high as 14.5%, cranial neuro increases from 4 to 29%. SUBJECTS AND METHODS 1. Subjects. 60 patients were diagnosed with sphenoid wing meningiomas and operated in Vietduc Hospital from March 2013 to September 2015 with adequate profiles and hermatology of menigioma. Patients were assigned to 3 groups depending on the sites of the tumor. Group 1: outer part of the sphenoid ridge (lateral); group 2: middle part of the sphenoid ridge (intermediate); group 3: inner part of the sphenoid ridge (medial). This database included 24 tumors of the medial sphenoid ridge and 08 tumors of lateral sphenoid ridge and 28 tumors of middle. * 198 Hospital ** Vietduc Hospital *** 103 Military Hospital Corresponding author: Do Van Dung (doctordung1969@gmail.com) Date received: 08/11/2017 Date accepted: 28/02/2018 Journal of military pharmaco-medicine n 0 3-2018 141 Cushing and Eisenhardt (1938) [6] were the first to describe the sphenoid wing by dividing it into thirds, with changes in the orientation of the wing roughly demarcating the boundaries of these segments; firstly, a medial third, which represents the medial posterior-to-anterior segment, the most adjacent to the anterior clinoid process; a middle third, which runs medial to lateral and lastly, a lateral third, which runs anterior to posterior. 2. Method. This is a descriptive and interventional study with follow-up. The Chi-square test was used for statistical analysis and comparisons between different groups. Probability values of less than 0.05 indicated significant diferences. * Perioperative management: Preoperative evaluation of all patients included T1-and/orT2-weighted MRI studies obtained with or without contrast. Use of contrast allows visualization of the extent of tumor while T2 images may display the arachnoid layer around the tumor and also adjacent brain edema, the latter giving some indication of adhesion to the surrounding parenchyma [1, 3, 9]. - Surgical techniques: All patients were positioned supine with the head elevated slightly above the heart to promote venous drainage. The head was rotated 30 degrees opposite the side of the tumor, bringing the sphenoid ridge into a vertical orientation. A fronto-temporal (pterional) craniotomy was performed. Using a high-speed pneumatic drill and remaining extradural, drilling of the lesser wing reach anterior clinoid and clinoidectomy in medial meningioma resections. After the tumor was exposed, tumor debulking was managed in piecemeal removal, base of tumor could be determined and major feeding artery was bloked. If the tumor invased into cavernous sinus, the extracavernous portion of tumor was removed while preserving neurovascular structures of cavernous sinus [4, 8, 9, 10]. - Assessment of tumor resection based on Simpson grade (Simpson D, 1957) [11]: Table 1: Grades Description Grade I Total tumors resection include the invation dura and skull Grade II Total tumors resection include the root tumor and burn the dura where the tumor stick Grade III Total tumor resection but leave the root and do not burn it Grade IV The large tumor resection Grade V Only decompression and bioxy * Surgical results: Evaluate the outcome of treatment, patients were assigned to a 03-category scoring system based on the Karnofsky performance score (KPS) [4]: Worse outcome with deterioration of symptoms or death: KPS 0 - 40; average with unchanged symptoms: KPS 50 - 70; good outcome KPS 80 - 100 with complete regression of preoperative tumor-related symptoms. Journal of military pharmaco-medicine n o 3-2018 142 * Follow-up examinations: After surgical treatment, patients were followed clinical and radiological examinations. The first follow-up was checked up MRI during 3 or 6 months after surgery. In cases with regrowth, patients were re-investigated at least after 1 year [2, 8]. RESULTS Table 2: The result of tumor resection (by area). Tumor positions Tumor resection (Simpson grade) Lateral Middle Medial Total p I 7 (87.5%) 9 (32.1%) 1 (4.2%) 17 II 1 (12.5%) 14 (50%) 4 (16.7%) 19 IV 0 5 (17.9%) 19 (79.1%) 24 Total 8 28 24 60 0.000 The difference between these three positions is statistically significant (p < 0.05). Total tumor resection at the position of 1/3 inside is lower than the other positions. Table 3: Karnofsky performance score (KPS) result before and after surgery. KPS before surgery KPS after surgery Result n % n % p Good (KPS: 80 - 100) 23 38.3% 39 65% Average (KPS: 50 - 70) 33 55% 18 30% Worse (KPS: 0 - 40) 4 6.7% 3 5% Total 60 100 60 100 0.012 Patients have better KPS after the surgery, statistically significant (p < 0.05). Mortality 5%. Table 4: Rehabilitation of neurological deficits before and after surgery (n = 52). Cranial nervous Before surgery Imprvove Unimprove II 21 5 (23.81%) 16 (76.19%) III 26 17 (65.39%%) 9 (34.61%) IV 7 4 (57.14%) 3 (42.86%) V 24 7 (29.2%) 17 (70.8%) VI 13 7 (53.85%) 6 (46.15%) Vision improvement after surgery is still limited, in which the cranial nerve number III improves the best after surgery. Journal of military pharmaco-medicine n 0 3-2018 143 Table 5: Residual and recurrence. MRI n % Total resection 31 59.7 Subtotal resection 21 40.3 Recurrence 8 15.4 DISCUSSION 1. Evaluate the degree of tumor resection. How to get rid of tumor is still controversial. In our report as well as other authors’, we use the chart for the degree of tumor resection (Simpson D, 1957) [11]: all tumor resection (grade I, II) achieved 60%, left subtotal resection accounted for 40%. In some recent reports, Attia M (2012) [2] have the capture result after surgery with 07 cases (31.8%) of thorough removal, 68.2% residual. Scheitzach J.D and his partner (2014) [10] conducted a research on 227 patients, of which 67 patients with SWMs found 34.5% of tumor residual. 2.7% of them suffered from grade IV resection. Result of all tumor resection at medial sphenoid wing is still limited but it proves that the tumor location is very important to tumor removal, the position 1/3 inside just take up 5/24 cases (20.8%), this difference is statistically significant. We also realized that the position of the tumor is of great significance in tumor resection (p < 0.05). Complete removal is more difficult when the site of origin is more medial and the extension of the tumor is greater. In meningiomas located at the outer part of the ridge, complete resection is possible in almost every case, except for those with vascular encircling. In a considerable amount of sphenoid wing meningiomas of the middle or inner region, total resection is unrecognizable without an unacceptable risk of additional morbidity including its cranial nerves and adjacent arteries, posteriorly. Therefore, some authors proposed to reconceive the original Simpson’s classification due to a close relationship to neurovascular structures, where radical dural resection is more hazardous compared to supratentorial convexity meningiomas [2, 8]. 2. The result of surgery. Patients’ post-operation outcome (KPS 80 - 100 points): good outcome accounted for 65%, average 30%, worse 5%. Compared with the KPS before surgery, we realized that the patients in average group reduced, so this difference was statisticaly significant (p < 0.05). Abdel Aziz (2004) [1] also recorded the results after surgery following the KPS: good outcome in the first 3 months achieved 74%, bad 26%, no normal result. This rate in the study by Honig S (2010) [7] in the first 3 months after surgery was 77.8% good, 11.1% normal (5 cases), 8.9% bad (4 cases). Stephen M.R (2008) [11] also confirmed good result in 32.4%, bad: 11. 8%. Hence, in this study, the average outcome was to be expected for group of medial sphenoid wing meningiomas due to less surgical accessibility, more frequent vascular and nerve involvement and a higher incidence of preoperative neurological deficit. 3. Mortality. Three patients died after surgery, two of whom had giant tumors at medial sphenoid wing due to intra-operative Journal of military pharmaco-medicine n o 3-2018 144 bleeding and massive cerebral edema after surgery and a patient died during follow-up period of heart disease. Mortallity rate in our study was 5%. We realized that when the tumor adhered to the ICA or cavernous sinus, anterior clinoid process and large vascular feeding, we should be cautious otherwise there will be injury of neurovascular structures and vasopasm during operation and complication may occur after surgery such as hematoma, ischemia, edema, infarction. Some recent reports also revealed a high mortallity like the study by Honig S (2010) [7] (4.7%); Verma S.K (2016) (2.6%)... 4. Cranial nervous outcome. Our result shows that the vision recovery after surgery is limited, especially the patients whose vision are still counting fingers and blind. Improvement of cranial nerver number II: 23.81%, visual disturbance symptoms concentrated at the medial sphenoid wing meningiomas, optic canal invasion and carvenous sinus involvement are frequent features of these tumors. Most of all researches announced about the limitation in vision recovery after tumor resection. Like those authors, however, we realized that the result depended on the tumor expense with the other parts like the visual tract, into the visual hole and the degree of adhesion to the visual cords and the subtotal tumor resection. Nakamura and his partner (2006) [9] also discussed the cranial nerve deficit from 4 - 29% and realized that in some reports about medial sphenoid wing meningiomas involved with cavernous sinus, there will be poor recovery. In his study, Verma S.K (2016) reported 11/58 (18.9%) cases suffered from cranial nerve paralysis III, IV, VI before surgery and didn’t improve after surgery because tumor expended cavernous sinus, 6 cases were affected by cranial nerve V. Scheizach J (2014) [10] didn’t find the colleration between the tumor resection and tumor deficit recovery. Our result showed that this improvement wasn’t associated with tumor resection. 5. Evaluate the tumor residual and reccurence after surgery. Most meningiomas are benign, the reccurence time is usually slow after surgery in both total and subtotal resection, therefore, we as well as the other authors indicated that after 12 months’ surgery the view of meningiomas at the surgery position is still residual tumor. Nakamura (2006) [9] reported that average reccurence time was 32 months. In our research, reccurence rate was 15.4%, our mean time was 14.5 months, which is shorter than that in the other studies, so the reccurence has low confident value. We all agree that tumor reccurence depends on many factors, mainly tumor resection and histopathology. Hence, the aim of the surgery was to resect all the tumors which the tough part sticks to, the effected bone will limit the reccurence time. But it seems to be a great challenge to remove all the tumor at the position of 1/3 inside . Journal of military pharmaco-medicine n 0 3-2018 145 CONCLUSION After studying 60 patients who were diagnosed with sphenoid wing meningiomas and treated at Vietduc Hospital from April 2013 to September 2015, we drew out some conclusions: - Surgical management of meningiomas involving the sphenoid ridge does not contribute to increased procedure-related morbidity compared to other intracranial meningiomas. However, meningiomas involving vascular structures of ICA (internal carotid atery) and MCA (middle cerebral atery) still has high mortality. Complete resection is feasible in nearly all cases with lateral located sphenoid wing meningioma. In cases of meningiomas of the middle or medial, total removal should not be attempted at the expense of new cranial nerve deficits or visual deterioration. With a view to improving the quality of life after operation, incomplete resection should be considered as an acceptable treatment option. The outcome is worse in medial meningiomas due to less surgical accessibility, greater vascular and nerve involvement and a higher incidence of preoperative neurological deficits. All patients should be followed closely with clinical, ophthalmological and radiological investigations to identify timely tumor regrowth. REFERENCE 1. Abdel Aziz K.M. Large sphenoid wing meningioma involving the cavernous sinus: Conservative surgical strategies for better functional oucomes. Neurosurgery. 2004, 54, pp.1375-1384. 2. Attia M, Umansky F. Giant anterior clinoidal meningiomas: surgical techniqueand outcomes. J Neurosurg. 2012, 117, pp.654-665. 3. Bassiouni H, Siamak Asgari S. Anterior clinoidal meningiomas: functional outcome after microsurgical resection in a consecutive series of 106 patients. J Neurosurg. 2009, 111, pp.1078-1090. 4. Behari S, Giri P et al. Surgical strategies for giant medial sphenoid wing meningiomas: a new scoring system for predicting extent of resection. Acta Neurochir (Wien). 2008, 150, pp.865-877. 5. Chaichana K.L et al. Predictors of visual outcome following surgical resection of medial sphenoid wing meningiomas. J Neurol Surg B. 2012, 73, pp.321-326. 6. Cushing H, Eisenhardt L. Meningiomas: Their classification, regional behaviour, life history, and surgical and results. Springfield, IL, Charles C Thomas. 1938. 7. Honig S, Trantakis S et al. Spheno- orbital meningiomas: outcome after microsurgical treatment: a clinical review of 30 cases. Neurolneurochirpol. 2010, 44, pp.464-474. 8. Jun Y, Chang S. Large and giant medial sphenoid wing meningiomas involving vascular structures: clinical features and management experience in 53 patients. Chin Med J. 2013, 126 (23). 9. Nakamura M et al. Medial sphenoid wing meningioma: Clinical outcome and recurrence rate. Neurosurgery. 2006, 58, pp.626-639. 10. Scheitzach J, Schebesch K.M. Skull base meningiomas: Neurological outcome after microsurgical resection. J Neurooncol. 2014, 116, pp.381-386. 11. Simpson D. The recurrence of intracranial meningiomas after surgical treatmen. J Neurol Neurosurgical Psychiary.1957, 20, pp.22-39.