The radical transbasal approach for resection of anterior and midline skull base lesions

OBJECT: Craniofacial surgery can be performed to treat midline and anterior skull base lesions by creating a bicoronal scalp incision without the need for an additional transfacial procedure. Originally described as the transbasal approach, several modifications for further exposure of the skull base have been described. The authors present data on the application and outcomes of a modified transbasal approach. The radical transbasal approach consists of a bifrontal craniotomy and a frontoorbitonasal osteotomy. METHODS: Between 1992 and 2002, 41 patients (28 male and 13 female patients with a mean age of 38.3 years [range 7-77 years]) underwent 44 radical transbasal procedures. Twenty-three malignant and 18 benign lesions involving the midline skull base were treated. These cases were reviewed retrospectively. Gross-total resection of 30 lesions was achieved. Seven lesions were resected subtotally and six partially; one lesion was debulked. Complications occurred in 26 (59.1%) of the 44 operations and mostly consisted of cerebrospinal fluid leakage. The surgery-related mortality rate was 6.8% (three patients). Based on their pre- and postoperative Karnofsky Performance Scale scores, 86.4% of patients improved or remained the same. CONCLUSIONS: The radical transbasal approach increases the midline craniofacial corridor by allowing the globes to be safely retracted laterally. It also enhances exposure of the maxillary sinus from above. The morbidity and mortality rates associated with this procedure are high but consistent with the known rates for craniofacial surgery. This approach is best suited for the treatment of anterior skull base tumors that extend into the nasal cavity, orbit, ethmoid sinus, nasopharynx, and upper clivus. The approach may allow resection of tumors involving the maxillary sinus area without the need for an additional transfacial approach.     

Frontal skull base surgery combined with endonasal endoscopic sinus surgery

BACKGROUND: Postoperative infection remains a serious complication after radical resection of anterior skull base lesions because intracranial, nasal, and paranasal cavities are opened during surgery. To prevent complications from postoperative infection, we combined endonasal endoscopic sinus surgery (ESS) with the frontal transbasal approach in patients with skull base lesions. METHODS: Patients (n = 16) with anterior skull base lesions extending to the paranasal or nasal cavity underwent surgical resection via the frontal transbasal approach. After removal of the lesion via the transcranial approach, enlargement of the ostium or sinusotomy was performed bilaterally using our endonasal ESS procedure. The main purpose of ESS is the establishment of a wide drainage route to avoid dead space and postoperative infection. Furthermore, we confirmed the absence of residual lesion and leakage of cerebrospinal fluid (CSF), endoscopically. RESULTS: The frontal transbasal approach combined with endonasal ESS was performed in 16 patients with frontal skull base lesions. There were 8 malignant tumors, 6 benign tumors, and 2 mucoceles. Although 11 patients had preoperative active paranasal sinusitis, most frequently at the ethmoid sinus, none experienced postoperative infection. There was no complication related to ESS procedure. Furthermore, leakage of CSF and extracranial residual tumor were not found. CONCLUSION: Endonasal ESS after frontal skull base surgery is a highly useful technique for preventing postoperative infection, especially for the cases with large skull base tumors extending into other regions involving the paranasal sinuses or nasal cavity and with active paranasal sinusitis.     

Primary meningioma of paranasal sinuses treated by the transbasal approach

The authors found the transbasal approach very useful for the treatment of a meningioma originating in the paranasal sinus and massively involving the anterior cranial base. By this approach, both total excision of the tumor and reconstruction of the base of the skull were successfully achieved at the same operation. The usefulness of the transbasal approach as well as the clinicopathologic features of the meningiomas arising in the paranasal sinus are described.     

Case of frontal sinus carcinoma for which anterior skull base surgery was performed: application for resection of orbita

Carcinoma of the nasal cavity and paranasal sinuses occupies only 3% of head and neck malignant tumors in the West, but 10% in Japan. Frontal sinus carcinoma is much rarer, occupying less than 1% of carcinoma of the nasal cavity and paranasal sinuses. In Japan, only 38 cases have been reported for 40 years, from 1924 to 1964. Almost all patients died within one year because only facial resection was performed. We report a case of frontal sinus carcinoma (squamous cell carcinoma) invasive the to skull base for which we performed anterior skull base surgery and can confirm two years survival in our institution. In this case, resection of the right orbit contents was performed, but careful consideration must be given to resection and repair of orbit contents for maintaining a patient's quality of life. Not only computed tomography scan and magnetic resonance imaging but also angiography is thought to be useful, especially for the ophthalmic artery (in this case, the lacrimal artery) is important.     

Telecanthal approach for meningiomas in the ethmoid and sphenoid sinuses

In three cases involving meningiomas in the ethmoid and sphenoid sinuses, transbasal spreading of the interocular distance (telecanthal approach) was used for tumor removal and reconstruction of the skull base. This telecanthal approach involves 1) bilateral en bloc removal of the superior lateral rim of the orbit, the nasal bone, and the posterior lateral wall of the orbit; 2) detachment of the medial canthal ligaments; and 3) spreading of the interocular distance. This approach provides a wide working space beneath the anterior half of the midline skull base, and needs neither a facial incision nor significant retraction of the brain. The surgical technique and its modification are described. The discussion focuses not only on comparisons with other techniques, but on the indications for this approach. Meningiomas originating in the paranasal sinuses are rare; a brief review of the literature concerning the clinicopathological features and pathogenesis is also given.     

Transcranial resection of tumors of the paranasal sinuses and nasal cavity

Combined cranial and facial procedures for resection of malignancies of the paranasal sinuses and nasal cavity have been used with variable success and complication rates in the last 25 years. A series of nine patients undergoing 10 exclusively transcranial procedures for these tumors is presented, and an effective technique for reconstruction without free tissue transfer is described. The patients in this series suffered no major complications, and all have remained free of disease during the short follow-up period. The technique described in this report offers the advantage of wide exposure, symmetrical approach to the superstructures of the face and orbits, the potential for resection of a large portion of the anterior cranial floor, and substantial reconstruction which is a major factor in avoiding complications.     

Endoscopic-assisted craniofacial resection of esthesioneuroblastoma: minimizing facial incisions--technical note and report of 3 cases.

The surgical management of esthesioneuroblastoma with anterior skull base involvement has traditionally been craniofacial resection, which combines a bifrontal craniotomy with a transfacial approach. The latter usually involves a disfiguring facial incision, mid-facial degloving, lateral rhinotomy, and/or extensive facial osteotomies, which may be cosmetically displeasing to the patient. The advent of angled endoscopes has provided excellent magnification and illumination for surgeons to remove tumors using minimally invasive techniques. The authors describe their experience with three cases of esthesioneuroblastoma, which were surgically removed using a transnasal endoscopic approach, avoiding transfacial incisions. Preoperative radiographs were reviewed and tumors were staged according to the Kadish staging system. One patient had a recurrent esthesioneuroblastoma (Kadish stage B), which was removed entirely through a transnasal endoscopic approach. Two patients had intracranial extension (Kadish stage C), which were resected with a combined approach, endoscopically from below and a bifrontal craniotomy from above, to remove intracranial disease. All patients underwent reconstruction of the anterior skull base. Esthesioneuroblastomas confined to the nasal and paranasal cavities (Kadish stage A and B) were readily accessible through the transnasal endoscopic approach. If there was significant intracranial disease (Kadish stage C), adding a bifrontal craniotomy provided excellent exposure for complete resection of involved tumor. All patients underwent complete tumor resection with negative margins. None developed a cerebrospinal fluid (CSF) leak. The endoscopic-assisted craniofacial approach for the surgical management of esthesioneuroblastomas provides excellent exposure, adequate visualization, and the cosmetic benefit of avoiding an external facial incision.     

Facial translocation: a new approach to the cranial base

Nasopharynx, clivus, and cavernous sinus are difficult regions of the cranial base in which to perform oncologic surgery. We have developed an approach to this area by using facial soft tissue translocation and craniofacial osteotomies. Surgical field obtained at the skull base can extend from the contralateral eustachian tube to ipsilateral geniculate ganglion. It includes the nasopharynx, clivus, sphenoid, and cavernous sinus, as well as the entire infratemporal fossa and superior orbital fissure. Our experience with this technique in 12 patients is reported. All patients healed primarily.     

The use of the facial translocation technique in the management of tumors of the paranasal sinuses and skull base.

OBJECTIVE: We sought to assess the efficacy of facial translocation in the management of tumors of the skull base and paranasal sinuses. STUDY DESIGN AND SETTING: From July 1993 to December 1999, 75 patients, aged 3 to 102 years old, underwent facial translocation. Thirty-three (44%) patients also underwent a combined neurosurgical procedure. Nineteen (25%) had previous surgery. These patients were followed up to 6 years. RESULTS: There were 21 benign and 54 malignant tumors. There were no perioperative deaths. The morbidity rate was 31%. Of the 54 patients with malignant tumors, the actuarial 3-year survival rate was 59%, whereas the local control rate was 54%. CONCLUSION: The facial translocation technique offers favorable exposure of the critical zones of the anterior and middle cranial base, thus facilitating extensive resection and reconstruction. SIGNIFICANCE: This study demonstrates that facial translocation is one of the best surgical approaches to the skull base.     

扩大经蝶入路显微手术切除斜坡脊索瘤

目的 报道应用扩大经蝶入路治疗斜坡脊索瘤的临床效果.方法 采用扩大经蝶入路显微手术切除斜坡脊索瘤病例9例(均经病理结果证实),所有病例均在神经导航下进行,其中经唇下-扩大经蝶入路4例,经鼻-扩大经蝶入路5例.4例术前通过虚拟现实系统实现图像三维重建,明确肿瘤与周围重要结构的关系,以更好的指导手术入路.结果 肿瘤术中显微镜下及术后影像学证实完全切除3例,肿瘤镜下次全切除(切除比例大于90%)6例.其中2例因肿瘤侵犯至硬脑膜下,肿瘤切除后出现脑脊液漏,经颅底重建修补后痊愈.结论 扩大经蝶入路显微手术可以简单迅速地到达斜坡区域,并能较充分地暴露前颅底、中下斜坡以及双侧海绵窦区,术后并发症少,创伤小,对斜坡脊索瘤来讲是一种较好的手术方式.     

Combined Transoral and Endoscopic Approach for Total Maxillectomy: A Pioneering Report

Total maxillectomy is sometimes necessary especially for malignant tumors originating from the maxillary sinus. Here we describe a combined transoral and endoscopic approach for total maxillectomy for the treatment of malignant maxillary sinus tumors and evaluate its short-term outcome. This approach was evaluated in terms of the physiological function, aesthetic outcome, and complications. Six patients underwent the above-mentioned approach for resection of malignant maxillary sinus tumors from May 2010 to June 2011. This combined transoral and endoscopic approach includes five basic steps: total sphenoethmoidectomy, sublabial incision, incision of the frontal process of the maxilla, incision of the zygomaticomaxillary fissure, and hard palate osteotomy. All patients with malignant maxillary sinus tumors successfully underwent the planned total endoscopic maxillectomy without the need for facial incision or transfixion of the nasal septum; there were no significant complications. Five patients received preoperative radiation therapy. All patients were well and had no recurrence at follow-up from 13 to 27 months. The combined approach is feasible and can be performed in carefully selected patients. The benefit of the absence of facial incisions or transfixion of the nasal septum, potential improvement in hemostasis, and visual magnification may help to decrease the morbidity of traditional open approaches.     

Craniofacial resection for anterior skull base tumours

Summary This study presents a series of 10 patients with anterior skull base tumours, treated by a team of neurosurgeons and head- and neck surgeons. The series included 7 malignant tumours of the nose and paranasal sinuses and 1 retinoblastoma, all with intracranial extension through the lamina cribrosa. There were also 2 patients with an anterior base meningioma, growing into the ethmoid sinus and the nasal cavity.8 tumours were resected by a combined bifrontal craniotomy and uni- or bilateral rhinotomy. In 2 cases a bifrontal craniotomy alone without facial incision sufficed. The skull base was closed with a pediculated pericranial flap and a split-thickness free skin graft underneath.There were no postoperative problems of wound infection, CSF-leakage or meningitis. Recurrent tumour growth or systemic metastasis occurred in 5 out of 7 patients with malignant tumours, 6 months to 2 years postoperatively.The related literature and especially questions of operative indications and technique, including different possibilities of closure and reconstruction of the skull base, are discussed.     

内窥镜下直接经蝶入路切除垂体腺瘤

目的 探讨内窥镜控制下直接经蝶入路切除垂体腺瘤的方法。方法 22例垂体腺瘤患者,在内窥镜控制下,经单鼻孔进入,术中不切除鼻中隔,直接自蝶窦开口打开蝶突前壁,进一步经鞍底切除垂体腺瘤。结果 22例患者中,15例肿瘤全部切除,7例肿瘤次全切除。术后随访1－12个月,17例患者内分泌功能恢复正常。4例术后发生暂时性尿崩症。结论 内窥镜控制下直接经蝶切除垂体腺瘤入路与目前常规经蝶显微手术比较,入路途径较短,且安全简捷、损伤小,手术显露良好,术后反应小,值得进一步推广。     

Radiologic Assessment of the Paranasal Sinuses after Endoscopic Skull Base Surgery

Objectives To identify sinuses demonstrating postoperative radiographic mucosal thickening after endoscopic exposure of the cranial base through the transsphenoidal corridor. Design Retrospective review. Setting University-based medical center. Participants Patients undergoing endoscopic transnasal transsphenoidal approaches to the skull base who had both preoperative and postoperative imaging. Main Outcome Measures Change in preoperative and postoperative imaging scores for each sinus and side at 3 and 6 months. The left-sided undissected sinuses served as internal controls for comparison. Results Fifty-one patients were identified with the aforementioned inclusion and exclusion criteria. The mean difference in preoperative and postoperative imaging scores for the right anterior ethmoid sinus was significantly different from the left-sided equivalents (p = 0.0020). The difference in the frontal sinuses approached significance (p = 0.0625). Conclusions Resection of the lower half of the middle turbinate and maxillary antrostomy and harvest of a nasoseptal flap are associated with an increased radiographic incidence of mucosal thickening of the ipsilateral anterior ethmoids compared with the undissected contralateral side. When accessing the transnasal transsphenoidal corridor for skull base surgery, preservation of native anatomy is associated with a lower incidence of mucosal thickening on postoperative imaging.     

Variations on the standard transsphenoidal approach to the sellar region, with emphasis on the extended approaches and parasellar approaches: surgical experience in 105 cases

OBJECTIVE: The traditional boundaries of the transsphenoidal approach may be expanded to include the region from the cribriform plate of the anterior cranial base to the inferior clivus in the anteroposterior plane, and laterally to expose the cavernous cranial nerves and the optic canal. We review our combined experience with these variations on the transsphenoidal approach to various lesions of the sellar and parasellar region. METHODS: From 1982 to 2003, we used the extended and parasellar transsphenoidal approaches in 105 patients presenting with a variety of lesions of the parasellar region. This study specifically reviews the breadth of pathological lesions operated and the complications associated with the approaches. RESULTS: Variations of the standard transsphenoidal approach have been used in the following series: 30 cases of pituitary adenomas extending laterally to involve the cavernous sinus, 27 craniopharyngiomas, 11 tuberculum/diaphragma sellae meningiomas, 10 sphenoid sinus mucoceles, 18 clivus chordomas, 4 cases of carcinoma of the sphenoid sinus, 2 cases of breast carcinoma metastatic to the sella, and 3 cases of monostotic fibrous dysplasia involving the clivus. There was no mortality in the series. Permanent neurological complications included one case of monocular blindness, one case of permanent diabetes insipidus, and two permanent cavernous cranial neuropathies. There were four cases of internal carotid artery hemorrhage, one of which required ligation of the cervical internal carotid artery and resulted in hemiparesis. The incidence of postoperative cerebrospinal fluid fistulae was 6% (6 of 105 cases). CONCLUSION: These modifications of the standard transsphenoidal approach are useful for lesions within the boundaries noted above, they offer excellent alternatives to transcranial approaches for these lesions, and they avoid prolonged exposure time and brain retraction. Technical details are discussed and illustrative cases presented.     

Extended frontal approach with bilateral orbitofrontoethmoidal osteotomies for removal of a giant extracranial schwannoma in the nasopharynx, sphenoid sinus, and parapharyngeal space

BACKGROUND: Although parapharyngeal schwannomas are not uncommon, schwannomas of the nasopharynx and paranasal sinuses are rare lesions. In the absence of intracranial extension, they are usually removed with transantral, lateral rhinotomy or more complex transfacial approaches. CASE DESCRIPTION: We report a 24-year-old patient with a giant benign schwannoma involving the superior parapharyngeal space, pterygopalatine fossa, nasopharynx, and sphenoid sinus with erosion into the clivus that was removed with an extended frontal approach including bilateral orbitofrontoethmoidal osteotomies. CONCLUSION: The advantages of the extended subfrontal over more standard transfacial approaches for lesions in this location include the early dissection of critical neural structures, preserving cosmetics and facilitating management of an inadvertent cerebrospinal fluid leak.     

Facial translocation approach to the cranial base: the anatomic basis

Surgical exposure of the nasopharyngeal region of the cranial base is difficult because of its proximity to key anatomic structures. Our laboratory study outlines the anatomic basis for a new approach to this complex topography. Dissections were performed on eight cadaver halves and two fresh specimens injected with intravascular silicone rubber compound. By utilizing facial soft tissue translocation combined with craniofacial osteotomies; a wide surgical field can be obtained at the skull base. The accessible surgical field extends from the contralateral custachian tube to the ipsilateral geniculate ganglion, including the nasopharyax; clivus, sphonoid, and cavernous sinuses, the entire infratemporal fossa, and superior orbital fissure. The facial translocation approach offers previously unavailable wide and direct exposure, with a potential for immediate reconstruction, of this complex region of the cranial base.     

Facial Translocation Approach to the Cranial Base: The Anatomic Basis

Surgical exposure of the nasopharyngeal region of the cranial base is difficult because of its proximity to key anatomic structures. Our laboratory study outlines the anatomic basis for a new approach to this complex topography. Dissections were performed on eight cadaver halves and two fresh specimens injected with intravascular silicone rubber compound. By utilizing facial soft tissue translocation combined with craniofacial osteotomies; a wide surgical field can be obtained at the skull base. The accessible surgical field extends from the contralateral custachian tube to the ipsilateral geniculate ganglion, including the nasopharyax; clivus, sphonoid, and cavernous sinuses, the entire infratemporal fossa, and superior orbital fissure. The facial translocation approach offers previously unavailable wide and direct exposure, with a potential for immediate reconstruction, of this complex region of the cranial base.     

The Extended Transbasal Approach: A Quantitative Anatomical and Histological Study

Summary  Since its introduction in 1972 the transbasal approach to the anterior fossa and sphenoethmoidal region has undergone a number of modifications. The extended transbasal approach with preservation of olfaction not only improves exposure of the anterior fossa, but also provides access to the clivus as far inferiorly as the foramen magnum.  An anatomical study has been undertaken to photographically demonstrate and quantify the varying degrees of exposure that this technique provides. The pituitary stalk was used as an intracranial target. The amount of exposure was compared using a standard subfrontal approach, a transbasal approach and an extended transbasal with preservation of olfaction. In addition, a histological study was carried out to investigate the level to which identifiable olfactory nerves extended into the nasal mucosa.  The anatomical study demonstrates the area of the “external window of exposure” can be doubled using a transbasal approach and more than quadrupled using the extended transbasal approach, when gaining access to the pituitary stalk. In addition, the study highlights the exposure of other anatomical areas, such as the medial orbit, the cavernous sinus, the clivus and the vertebrobasilar complex. The histological study establishes that the olfactory nerves extend only 10mms below the cribriform plate.     

Malignant solitary fibrous tumor of the nasal cavity.

Solitary fibrous tumors (SFTs) are unusual mesenchymal tumors that were first described as primary spindle-cell neoplasms of the pleura. These tumors have been described in many other locations, including the urogenital system, orbit, mediastinum, and upper respiratory tract. Twenty-two cases of an SFT of the paranasal sinuses and nasal cavity have been reported, but none described a malignant SFT extending through the anterior skull base. A 70-year-old man had a 6-month history of unilateral left-sided epiphora and nasal obstruction. Computed tomography and magnetic resonance imaging showed a large left-sided nasal cavity mass with extension into the left extraconal orbit and intracranial extension through the left cribriform plate and ethmoid roof. The patient underwent preoperative embolization of the internal maxillary artery and a subsequent anterior craniofacial resection via a midfacial degloving approach and a left anterior craniotomy. Histopathological analysis of the specimen was consistent with a malignant SFT.