Expanded Endonasal Approach Research Articles

Expanded endonasal approach, a fully endoscopic transnasal approach for the resection of midline suprasellar craniopharyngiomas: a new classification based on the infundibulum

Craniopharyngiomas are notoriously difficult to treat. Surgeons must weigh the risks of aggressive resection against the long-term challenges of recurrence. Because of their parasellar location, often extending well beyond the sella, these tumors challenge vision and pituitary and hypothalamic function. New techniques are needed to improve outcomes in patients with these tumors while decreasing treatment morbidity. An endoscopic expanded endonasal approach (EEA) is one such technique that warrants understanding and evaluation. The authors explain the techniques and approach used for the endoscopic endonasal resection of suprasellar craniopharyngiomas and introduce a tumor classification scheme. The techniques and approach used for the endoscopic, endonasal resection of suprasellar craniopharyngiomas is explained, including the introduction of a tumor classification scheme. This scheme is helpful for understanding both the appropriate expanded approach as well as relevant involved anatomy. The classification scheme divides tumors according to their suprasellar extension: Type I is preinfundibular; Type II is transinfundibular (extending into the stalk); Type III is retroinfundibular, extending behind the gland and stalk, and has 2 subdivisions (IIIa, extending into the third ventricle; and IIIb, extending into the interpeduncular cistern); and Type IV is isolated to the third ventricle and/or optic recess and is not accessible via an endonasal approach. The endoscopic EEA requires a thorough understanding of both sinus and skull base anatomy. Moreover, in its application for craniopharyngiomas, an understanding of tumor growth and extension with respect to the optic chiasm and infundibulum is critical to safely approach the lesion via an endonasal route.

ENDOSCOPIC ENDONASAL PITUITARY TRANSPOSITION FOR A TRANSDORSUM SELLAE APPROACH TO THE INTERPEDUNCULAR CISTERN

The interpeduncular cistern, including the retroinfundibular area, is one of the most challenging regions to approach surgically. The pituitary gland and the infundibulum guard the region when an endonasal route is undertaken. Superior transposition of the pituitary gland and infundibulum is described as a functional means to access this complex region through a fully endoscopic, completely transnasal route. Ten consecutive patients in whom a pituitary transposition was performed during an expanded endonasal approach at the University of Pittsburgh Medical Center for resection of retroinfundibular lesions were reviewed. The series consisted of seven men and three women with a mean age of 44.4 years. Pathology consisted of four craniopharyngiomas, four chordomas, and two petroclival meningiomas. Five patients (50%) underwent total resection of the tumor, three patients (30%) underwent near total resection ( > 95% removal), and two patients (20%) had partial resection of petroclival meningiomas with the goal of optic apparatus decompression. All four patients with visual deficits recovered their vision completely. There was no neurological deterioration. Eight patients had normal pituitary function preoperatively, seven of whom (87.5%) had confirmed function preservation postoperatively, with one of these patients experiencing transient diabetes insipidus. The remaining patient with a hypothalamic craniopharyngioma underwent complete resection with obligatory panhypopituitarism and diabetes insipidus. Endoscopic endonasal transposition of the pituitary gland and its stalk can provide a valuable corridor to the retroinfundibular space and interpeduncular cistern with pituitary function preservation in the majority of patients. This approach should only be pursued once significant experience with endoscopic endonasal approaches has been acquired.

Expanded endonasal approach: vidian canal as a landmark to the petrous internal carotid artery

The purpose of this study was to describe the technique used to safely identify the petrous carotid artery during expanded endonasal approaches to the skull base. A series of 20 cadaveric studies was undertaken to isolate the vidian artery and nerve and to use them as landmarks to the petrous internal carotid artery (ICA). Twenty-five consecutive paraclival endoscopic cases were also reviewed to determine the consistency of the vidian artery in vivo as an intraoperative landmark to the ICA. These data were then correlated with results from a separate study in which computed tomography scans from 44 patients were evaluated to delineate the course of the vidian canal and its relationship to the petrous ICA. In all 20 cadaveric dissections and all 25 surgical cases, the vidian artery was consistently identified and could be reliably used as a landmark to the ICA. The correlation between anatomical and clinical data in this paper supports the consistent use of the vidian artery as an important landmark to the petrous ICA.

Improving the Design of the Pedicled Nasoseptal Flap for Skull Base Reconstruction: A Radioanatomic Study

Reconstruction of the skull base after an expanded endonasal approach (EEA) is critical to achieve a good outcome. A novel technique based on the use of a pedicled nasoseptal flap has proven to be a reliable and versatile reconstructive option for extensive defects of the skull base. Data regarding the potential dimensions of a nasoseptal flap are lacking in the literature. This pilot study was developed to help optimize the design of the nasoseptal flap and to ensure that when harvesting the flap, its width and length are adequate to reconstruct the defects that are created by various EEAs. We analyzed the computed tomographic (CT) scans of four patients who underwent EEAs for skull base lesions. Sagittal and coronal CT reconstructions were generated from axial images. The measurements were divided into skull base measurements, flap dimensions required to cover skull base defects resulting from various EEAs, and potential maximal dimensions of the nasoseptal flap. Measurements were studied for three different EEAs: sellar/transplanar, transclival, and transcribiform/anterior skull base. We measured the potential defects for each of these EEAs and the nasoseptal flap dimensions that would be required to reconstruct them. We estimated all dimensions based on the most extensive defect that could result with each EEA. We then compared these with various modifications of the nasoseptal flap. Two male and two female patients were studied. Twenty-seven measurements were taken to compare the different skull base defects and nasoseptal flaps. The length of the nasal septum comprises sufficient mucoperichondrium and mucoperiosteum to allow the harvesting of a nasoseptal flap that could cover any defect resulting from an anterior skull base, a transsellar/transplanar, or a transclival EEA. Similarly, the height of the nasal septum has the potential to yield a nasoseptal flap with a width that is adequate to cover the laterolateral aspect of any defect of the anterior skull base and clivus. Skull base defects resulting from combined EEAs, such as those that would create a defect that comprises the skull base from sella turcica to frontal sinus, are beyond the potential dimensions of a single nasoseptal flap. This and other defects resulting from a combination of EEAs require other strategies, such as the use of bilateral nasoseptal flaps, or the use of other reconstructive options.

Experience with the Expanded Endonasal Approach for Resection of the Odontoid Process in Rheumatoid Disease

One of the common indications for removal of the odontoid process includes decompression of the cervicomedullary junction in patients with arthritic degeneration. Resection of the odontoid process can be accomplished using a completely transnasal endoscopic approach. A retrospective review was performed of patients with rheumatoid pannus undergoing transnasal endoscopic resection of the odontoid to assess preoperative characteristics, postoperative complications, and outcomes. Patients were followed for a minimum of 3 months in the postoperative period and/or until death. In addition to the primary procedure, those patients with preoperative cervical instability underwent posterior fusion of the upper cervical spine to the occiput for stabilization during the same hospitalization. Nine patients underwent transnasal endoscopic resection of the odontoid process for rheumatoid or degenerative pannus and brainstem compression. Perioperatively, four patients required a tracheostomy; two of whom had significant preoperative pharyngeal dysfunction. Two patients experienced postoperative velopharyngeal incompetence, which was transient. No patients had cerebrospinal fluid leaks, and there were no perioperative infectious complications noted. There was one delayed death in this patient cohort because of a presumed pulmonary embolus. Otherwise, all patients showed an improvement of their preoperative neurological symptoms. This early series of patients with rheumatoid pannus shows the feasibility of a fully endoscopic, completely transnasal approach for the resection of the odontoid process. Potential advantages include improved visualization, limited morbidity, decreased pain, and faster recovery than traditional approaches.

The Posterior Pedicle Inferior Turbinate Flap: A New Vascularized Flap for Skull Base Reconstruction

Expanded endonasal approaches (EEA) for the resection of lesions of the anterior and ventral skull base can create large defects with a significant risk of postoperative cerebrospinal fluid (CSF) leaks or exposure of the internal carotid artery. In these cases, a reconstruction using a vascularized flap facilitates rapid and complete healing of the defect. The Hadad-Bassagasteguy flap (HBF), a posterior pedicle nasoseptal flap, is our preferred reconstructive option; however, a prior posterior septectomy or prior wide sphenoidotomies preclude its use. We have developed two additional pedicled flaps to reconstruct these selected patients: the transpterygoid temporoparietal fascia flap, which is suitable for large defects, and the posterior pedicle inferior turbinate flap (PPITF), the subject of this paper. We developed a flap comprising the inferior turbinate mucoperiosteum pedicled on the inferior turbinate artery, a terminal branch of the posterior lateral nasal artery, which arises from the sphenopalatine artery. We retrospectively reviewed the clinical data of four patients who underwent a skull base reconstruction using a PPITF. Four patients underwent a reconstruction with the PPITF after undergoing an EEA that produced a skull base defect associated with a CSF fistula (n = 2), an exposed internal carotid artery (n = 1), or a basilar aneurysm clip (n = 1). All patients had undergone posterior septectomies as part of previous EEAs. All flaps healed uneventfully and covered the entire defect. The PPITF is a viable reconstructive option for patients with skull base defects of a limited size defect and in whom the HBF is not available.

Complications in Expanded Endonasal Approaches

Complications in Expanded Endonasal Approaches

Clinical Indications and Experience with the Expanded Endonasal Approach for Resection of the Odontoid Process

Clinical Indications and Experience with the Expanded Endonasal Approach for Resection of the Odontoid Process

Techniques of the Expanded Endonasal Approach to Lesions of the Anterior Cranial Base

Introduction: The traditional surgical approaches to the anterior skull base include bicoronal craniotomy, orbitocraniotomy, and anterior transbasal procedures. The expanded endonasal approach (EEA) provides direct access to the sella and anterior base while avoiding craniotomy and potential morbidity related to brain retraction.

The Caudal Expanded Endonasal Approach: A Fully Endoscopic Endonasal Approach for Resection of Lower Clival, Foramen Magnum, and Atlantoaxial Pathologies

The Caudal Expanded Endonasal Approach: A Fully Endoscopic Endonasal Approach for Resection of Lower Clival, Foramen Magnum, and Atlantoaxial Pathologies

Fully endoscopic expanded endonasal approach treating skull base lesions in pediatric patients

The authors reviewed their experience with endoscopic approaches to determine their safety and efficacy in the treatment of pediatric patients who harbor skull base lesions. Although they were interested in ascertaining outcomes after surgery as well as validating and defining indications and limitations of these approaches, the authors recognized that the follow-up duration was inadequate to assess long-term outcomes. The authors conducted a retrospective review of all endoscopic procedures performed at their institution between January 2000 and September 2005. The procedures were categorized into a series of anatomical modular approaches. Twenty-five patients 18 years of age or younger were identified. The surgical goals were individualized and included gross-total resection, partial resection, biopsy, decompression of neural structures, and repair of a cerebrospinal fluid (CSF) leak. One patient required an open procedure in addition to the expanded endonasal approach for definitive therapy. No patient suffered a neurological deficit, vascular injury, or central nervous system infection. A CSF leak was the most common complication and occurred in two (8%) of the 25 patients. In well-selected patients, the expanded endonasal approach represents a safe, effective, and minimally invasive technique for the treatment of skull base lesions in children. Incremental experience is needed for acquiring the skills with endoscopic techniques to progress to the more complex modular approaches.

Expanded endonasal approach: a fully endoscopic completely transnasal resection of a skull base arteriovenous malformation

Vascular lesions with an intraosseus nidus involving the skull base are uncommon and challenging [Gianoli GJ, Amedee RG Vascular malformation of the sphenoid sinus. Ear Nose Throat J. 70:373-375;(1991), Malik GM, Mahmood A, Mehta BA Dural arteriovenous malformation of the skull base with intraosseous vascular nidus. Report of two cases. J. Neurosurg 81:620-623;(1994)]. We present a pediatric patient, with a life-threatening arteriovenous malformation (AVM) of the sphenoid sinus, clivus, and ventral skull base, who failed routine multimodality management of AVMs. An entirely transsphenoidal fully endoscopic resection was used to resect this ventral cranial base AVM with an intraosseus nidus located in the clivus. A 4-year-old female presented with recurrent, life-threatening hemorrhages from a clival and ventral skull base AVM of the entire clivus and ventral skull base. The patient had been temporized from the age of 2-4 years with multiple internal and external carotid arterial particulate and alcohol embolizations, including both external and internal carotid artery embolizations, intracranial ligation of the right internal carotid artery, and gamma knife irradiation. Despite these multiple interventions, the patient had persistent, life-threatening hemorrhages from arterial recanalization and recruitment requiring intubation, tracheostomy, and nasopharyngeal packing. The patient underwent a three-stage surgical intervention to resect the AVM. An open subfrontal approach, as the first procedure, provided minimal access to the feeding vessels and was therefore aborted. A two-stage image-guided fully endoscopic approach via a sublabial midface approach without external incisions was performed. Postoperative angiography revealed minimal residual shunting in the pharynx and cavernous sinus. The patient has been free of significant hemorrhages over the past three years. Technological advances in endoscopic surgery and image guidance are now allowing for purely endoscopic surgical treatment of previously unresectable lesions with acceptable morbidity. We report the successful and safe resection of a ventral cranial base AVM via a fully endoscopic approach. This paper reports the first AVM with a purely intraosseus nidus of the ventral skull base and demonstrates the ability to deal with complex ventral skull base lesions using a fully endoscopic transsphenoidal technique.

Nasal Morbidity Associated with Expanded Endonasal Approaches to the Skull Base

Introduction: Expanded endonasal approaches (EEA) to the skull base are becoming an accepted surgical option for selected pathology involving the skull base. The purpose of this study is to review the nasal morbidity associated with this surgical approach.

Resection of the Odontoid Process through the Expanded Endonasal Approach: Clinical Experience from 14 Patients

Background: Indications for removal of the odontoid process include decompression of the brainstem in patients with rheumatoid degeneration and access to tumors or vascular lesions at the foramen magnum. Resection of the odontoid can be accomplished using a completely transnasal endoscopic approach.

Endoscopic Reconstruction of Cranial Base Defects following Endonasal Skull Base Surgery

The expanded endonasal approach provides access to the entire ventral skull base for resection of neoplasms involving the skull base and brain. The creation of large defects of the bone and dura endoscopically presents unique reconstructive challenges. A layered reconstruction of the dura with inlay and onlay fascial grafts covered with fat grafts is an effective technique for repair. An intranasal balloon catheter is used to provide counterpressure in the early phase of healing and a lumbar spinal drain is a useful adjunct in patients at increased risk of a cerebrospinal fluid leak. Vascularized flaps may be necessary in some patients receiving radiation therapy. Continued advances in surgical technology and the introduction of new biomaterials will facilitate the reconstruction of skull base defects following endonasal brain surgery.

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chondrosarcomas

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chondrosarcomas

Vascularized Nasal Septal Flap for Reconstruction of Skull Base Defects following Expanded Endonasal Approaches to the Skull Base: Outcome Analysis

Vascularized Nasal Septal Flap for Reconstruction of Skull Base Defects following Expanded Endonasal Approaches to the Skull Base: Outcome Analysis

The Surgical Management of Tuberculum Sellae Meningiomas

Introduction: Tuberculum sellae meningiomas represent 4 to 10% of all intracranial meningiomas. These tumors are surgically challenging because of their close proximity to the visual pathways, arteries of the anterior circulation, and pituitary gland and stalk. A variety of surgical approaches have been described in the literature for removal of these lesions, including the classic bilateral subfrontal craniotomy, the interhemispheric transbasal approach, the unilateral subfrontal approach with or without an orbital osteotomy, the frontotemporal (pterional) craniotomy, and more recently the expanded endonasal approach. Objective: The aim of this presentation is to review our own results and those from the literature of the different surgical approaches to tuberculum sellae meningiomas including completeness of tumor removal, visual outcome, vascular injury, and overall complication rates. Results: Advantages and disadvantages were identified with each surgical approach. Overall morbidity rates (15 to 30%), visual outcome (improvement 42 to 80%, worsening in 11 to 20%), and rates of total removal were comparable among the different approaches. Based on our own results and recent experience with the transbasal interhemispheric approach in 17 patients, this approach is favored because of the reduced need for brain retraction, improved bilateral visualization of critical neurovascular structures, and the ability to interrupt at an early stage the blood supply of the tumor, facilitating tumor resection. Conclusion: The majority of patients with tuberculum sellae meningiomas, regardless of the approach, can have their tumors totally removed with low mobidity and with variable rates of improvement in their vision. The author favors the transbasal interhemispheric approach.

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chordomas

Endoscopic Expanded Endonasal Approach for Resection of Skull Base Chordomas

Clinical Indications and Experience with the Expanded Endonasal Approach for Resection of the Odontoid Process

Purpose: Indications for removal of the odontoid process include decompression of the brainstem in patients with rheumatoid degeneration and access to tumors at the foramen magnum. Resection of the odontoid process can be accomplished using a completely transnasal endoscopic approach. Methods: Retrospective review of patients undergoing transnasal endoscopic resection of the odontoid to assess preoperative characteristics and postoperative complications and outcomes. Patients were followed for a minimum of 3 months in the postoperative period, and/or until death. In addition to the primary procedure, those patients with preoperative cervical instability underwent posterior fusion of the upper cervical spine to the occiput for stabilization during the same hospitalization. Results: Seven patients underwent transnasal endoscopic resection of the odontoid process for rheumatoid pannus and brainstem compression. Six patients had a transodontoid approach for resection of primary or metastatic neoplasms to the region of the skull base. One patient presented with an aneurysm of the right vertebrobasilar artery causing brainstem compression. Perioperatively, four patients required a tracheostomy; three of them had significant preoperative pharyngeal and/or respiratory dysfunction. Four patients had reparable cerebrospinal fluid leaks, and there were no infectious complications. There was one death in the rheumatoid arthritis group due to a pulmonary embolus. Deaths in the tumor-bearing groups were due to (1) ARDS and incidental finding of an obstructing pulmonary mass, and (2) status epilecticus associated with HIV-positive meningitis following excision of a posterior fossa intraparenchymal lesion. Otherwise, most patients demonstrated an improvement of their preoperative neurologic symptoms. No patients developed symptoms of prolonged palatal dysfunction. Conclusions: This early series demonstrates the feasibility of a fully endoscopic, completely transnasal approach for the resection of the odontoid process. Potential advantages include improved visualization, limited morbidity, decreased pain, and faster recovery than traditional approaches.