Suprasellar craniopharyngiomas have been classically removed using a variety of transcranial approaches. Historically, the transsphenoidal route was reserved for intrasellar-infradiaphragmatic, and ...preferably cystic, lesions. With the advent of the endoscope in transsphenoidal surgery, its obvious advantages combined with neurosurgeons' increasing interest in extended transsphenoidal approaches made suprasellar and even intraventricular craniopharyngiomas accessible for removal via such a low route.
Between January of 2004 and April of 2006, six men and four women (mean age, 57.2 yr; range, 26-70 yr) underwent surgery for craniopharyngioma, including two intrasuprasellar, one suprasellar, six suprasellar-intraventricular, and one that was purely intraventricular. Three patients had undergone a previous transcranial surgery via the pterional approach, whereas one patient had undergone a transsphenoidal microsurgical approach. The surgical method consisted of an extended endoscopic transsphenoidal approach with removal of the upper half of the sella, the tuberculum sellae, and the posterior part of the planum sphenoidale, using a "three-four hands" technique.
Total craniopharyngioma removal was achieved for seven patients, subtotal removal was possible for two patients, and one patient had a partial removal. Two patients developed a postoperative cerebrospinal fluid leak that required a successful endoscopic revision of the cranial base reconstruction. One patient died 5 weeks later because of hypothalamic dysfunction. All patients with visual field and/or visual acuity defect improved except one patient, in which we observed a slight worsening of visual acuity in one eye. Preoperative pituitary dysfunction did not improve in any patient. In three patients, we observed the new occurrence of permanent diabetes insipidus. One patient developed a sphenoid sinus mycosis, which was treated with antimycotic therapy. We did not observe carotid injury, epistaxis from the sphenopalatine artery, or airway difficulties.
For selected patients, the extended endoscopic endonasal approach for removal of suprasellar craniopharyngioma seems to provide a valid alternative to transcranial approaches.
The extended transsphenoidal approach to the suprasellar region has the advantages of minimal invasiveness and brain manipulation in the surgical treatment of small to medium lesions. At the same ...time, however, it carries a higher risk of postoperative cerebrospinal fluid (CSF) leakage and related complications than those for the standard transsphenoidal approach. Effective reconstruction of large skull base defects is a major concern in such extended approaches and remains challenging.
Between January 2004 and April 2006, 21 patients affected by different suprasellar lesions underwent the extended endoscopic endonasal transtuberculum-transplanum approach. Three different techniques were used for the skull base reconstructions. In all cases, dehydrated human pericardium (Tutoplast) for dural reconstruction and a copolymer of L-lactic acid and glycolic acid (LactoSorb) as a bone substitute were used. Collagen sponges, fibrin glue, and an inflated Foley balloon catheter were also used to fill the sphenoid sinus cavity.
Two cases of postoperative CSF leaks (9.5%) and one case of mycotic sinusitis (4.8%) occurred following the intradural (inlay) and intraextradural (inlay-overlay) graft positioning. No cases of postoperative CSF leakage occurred in cases in which the extradural-only reconstruction procedure was applied. No meningitis or other complications related to the closure were noticed.
The rate of postoperative CSF leakage after an extended approach to the suprasellar area is higher compared with that following standard pituitary surgery. Reconstruction after craniopharyngioma surgery exposes patients to an increased risk of postoperative CSF leaks. The extradural (overlay) technique was found to be the most effective in assuring a watertight closure.
The endoscopic endonasal transsphenoidal approach is a minimally invasive surgical technique for the removal of sellar and parasellar lesions. The procedure is performed via an anterior ...sphenoidotomy. The two main characteristics of the endoscopic approach, when compared with the standard microsurgical operation, arise from the use of the endoscope as a unique optical device and from the absence of a transsphenoidal retractor. More convenient straight surgical instruments are employed, whereas bayonet-shaped tools are used in the microsurgical procedure, to avoid any interference with the light beam generated by the microscope. The standard surgical technique is composed of three main time phases: the nasal, sphenoid, and sellar phase. During the nasal phase, the scope is introduced through the chosen nostril and advanced up to the sphenoethmoid recess, where the sphenoidotomy is performed. The sphenoid phase consists of the detachment of the nasal septum from the sphenoid rostrum, the anterior sphenoidotomy, removal of the sphenoid septum or septa, and identification of the landmarks inside the sphenoid sinus. In the sellar phase, an opening of the sellar floor is performed for removal of the lesion. A wide view of the sellar environment is obtained through angled scopes to detect eventual tumor remnants. The procedure ends with the reconstruction of the sella and removal of the endoscope from the nostril, without any postoperative nasal packing.
The extended transnasal approach, a recent surgical advancements for the ventral skull base, allows excellent midline access to and visibility of the anterior cranial fossa, which was previously ...thought to be approachable only via a transcranial route. The extended transnasal approach allows early decompression of the optic canals, obviates the need for brain retraction, and reduces neurovascular manipulation.
Between 2004 and 2007, 11 consecutive patients underwent transnasal resection of anterior cranial fossa meningiomas--4 olfactory groove (OGM) and 7 tuberculum sellae (TSM) meningiomas. Age at surgery, sex, symptoms, and imaging studies were reviewed. Tumor size and tumor extension were estimated, and the anteroposterior, vertical, and horizontal diameters were measred on MR images. Medical records, surgical complications, and outcomes of the patients were collected.
A gross-total removal of the lesion was achieved in 10 patients (91%), and in 1 patient with a TSM only a near-total (> 90%) resection was possible. Four patients with preoperative visual function defect had a complete recovery, whereas 3 patients experienced a transient worsening of vision, fully recovered within few days. In 3 patients (2 with TSMs and 1 with an OGM), a postoperative CSF leak occurred, requiring a endoscopic surgery for skull base defect repair. Another patient (a case involving a TSM) developed transient diabetes insipidus. The operative time ranged from 6 to 10 hours in the OGM group and from 4.5 to 9 hours in the TSM group. The mean duration of the hospital stay was 13.5 and 10 days in the OGM and TSM groups, respectively. Six patients (3 with OGMs and 3 with TSMs) required a blood transfusion. Surgery-related death occurred in 1 patient with TSM, in whom the tumor was successfully removed.
The technique offers a minimally invasive route to the midline anterior skull base, allowing the surgeon to avoid using brain retraction and reducing manipulation of the large vessels and optic apparatus; hastens postoperative recovery; and improves patient compliance. Further assessment and refinement are required, particularly because of the potential risk of CSF leakage. Other studies and longer follow-up periods are necessary to ascertain the benefits of the technique.
Recurrence of apparently completely resected benign meningiomas is a rather frequent event, the mechanisms of which are still unclear. The aim of this study is to define the pathological features, ...proliferation indexes, growth factors and hormone receptor expression in predicting the meningioma recurrence.
Two groups of 50 completely resected benign WHO I meningiomas, with and without recurrence respectively, have been reviewed. Tumor location, consistency, vascularity, and histological types have been considered. Immunohistological studies include mitotic index (MI), Ki-67 LI, estrogen and progesterone receptors (ER and PR), Vascular Endothelial Growth Factor (VEGF), Epidermal Growth Factor (EGF), and Bcl-2. All these factors have been correlated with the recurrence.
The tumor recurrence was not correlated with the patient age, tumor location, consistency, vascularity and histology. There was not difference in the histological pattern between local and diffuse recurrences. M.I. and Ki-67 LI were significantly correlated with the recurrence (P<0.0001). PR negativity had a strong predictive value of recurrence (P<0.0001), whereas the ER status was not relevant. VEGF and EGF-R were not correlated with the recurrence of meningiomas, whereas the Bcl-2 protein positivity showed a tendency to the significativity (P=0.0294). The negative association between Bcl-2 and PR is an interesting finding of our study.
Higher MI and Ki-67 LI and PR negativity are predictive factors of recurrence of benign (WHO I) completely resected meningiomas, particularly when Bcl-2 positivity is associated.
Tuberculum sellae meningiomas are classically removed through several different surgical transcranial approaches, including the pterional transsylvian route. Recently, the indications for the ...transsphenoidal technique, traditionally proposed only for the treatment of intrasellar lesions, have been extended to include lesions located in the supra- and parasellar areas and, among them, tuberculum sellae meningiomas. We describe the surgical technique for the purely endoscopic endonasal variant of the extended transsphenoidal "low route" to tuberculum sellae meningiomas.
Over a 22-month period, six patients (three men and three women; mean age, 56.1 yr; age range, 44-70 yr) underwent an extended endoscopic transsphenoidal approach for the treatment of tuberculum sellae meningiomas. Two lesions were less than 2 cm and four were between 2 and 4 cm in size. The details of the surgical technique have been described.
Gross total removal of the lesion, without the need for brain retraction and with minimal neurovascular manipulation, was achieved in five patients (83.3%), whereas in one patient, only subtotal removal was possible (>90%) because the mass extended into the right optic canal. Four patients with preoperative visual function defects had complete recovery, whereas two patients experienced a temporary worsening of vision. Both of these patients fully recovered within a few days. One patient had a postoperative cerebrospinal fluid leak that required three operations for cranial base defect repair. This patient showed rapid and unexpected worsening with respect to level of consciousness and anisocoria. An intraventricular hemorrhage was discovered, and the patient died 6 days later. Another patient developed new permanent diabetes insipidus that required hormonal replacement therapy.
In experienced hands and in carefully selected patients, the extended endoscopic transsphenoidal approach may constitute a viable alternative to transcranial approaches for tuberculum sellae meningioma. At present, the major limits of the approach include the lack of a reliable technique for the reconstruction of a cranial base defect and inadequate follow-up.
The midline skull base is an anatomical area that extends from the anterior limit of the cranial fossa down to the anterior border of the foramen magnum. Resection of lesions involving this area ...requires a variety of innovative skull base approaches. These include anterior, anterolateral, and posterolateral routes, performed either alone or in combination, and resection via these routes often requires extensive neurovascular manipulation. The goals in this study were to define the application of the endoscopic endonasal approach and to become more familiar with the views and skills associated with the technique by using cadaveric specimens.
To assess the feasibility of the endonasal route for the surgical management of lesions in the midline skull base, five fresh cadaver heads injected with colored latex were dissected using a modified endoscopic endonasal approach. Full access to the skull base and the cisternal space around it is possible with this route. From the crista galli to the spinomedullary junction, with incision of the dura mater, a complete visualization of the carotid and vertebrobasilar arterial systems and of all 12 of the cranial nerves is obtainable.
The major potential advantage of the endoscopic endonasal approach to the skull base is that it provides a direct anatomical route to the lesion without traversing any major neurovascular structures, obviating brain retraction. Many tumors grow in a medial-to-lateral direction, displacing structures laterally as they expand, creating natural corridors for their resection via an anteromedial approach. Potential disadvantages of this procedure include the relatively restricted working space and the danger of an inadequate dural repair with cerebrospinal fluid (CSF) leakage and potential for meningitis resulting. These approaches often require a large opening of the dura mater over the tuberculum sellae and posterior planum sphenoidale, or retroclival space. In addition, they typically involve large intraoperative CSF leaks, which necessitate precise and effective dural closure.
Objective A survey-based study was designed to assess opinions related to transsphenoidal endoscopy, to evaluate the current global attitudes of neurosurgeons regarding the use of this procedure, and ...to solicit basic data from key institutions worldwide, with the advantage that large series of cases become available for analysis. Methods A web-based multi-item questionnaire was distributed to the surgical departments of 393 neurosurgical centers by means of an invitation e-mail. The questionnaire was composed of 2 sections: section 1 focused on the surgical technique for pituitary adenomas (standard technique), and section 2 concentrated on surgery for skull base tumors (extended technique). Each section was composed of 2 parts: multiple choice questions and free textual responses. Results From a total of 393 neurosurgical centers, from 23 countries, that received the questionnaire, 87 of them (22%) submitted complete or incomplete responses. The surgical procedure, in 60 cases had been performed by a neurosurgeon, in 53 cases by a neurosurgeon and an otolaryngologist, and in 4 cases by an otolaryngologist only. The endoscope (2- and 3-dimensional) was used in 85.2% of transsphenoidal procedures versus the microscope in 14.8% of cases. The endonasal route was used for approach in 93.2% versus the sublabial route in 6.8% of cases. Computer-guided navigation was used by survey population in 71 cases, micro-Doppler in 51 cases, and Cavitron Ultrasonic Surgical Aspirator in 43 cases. Several hundreds of extrasellar tumors were operated using the extended technique. Conclusions Transsphenoidal endoscopy for pituitary and anterior skull base tumors has become established as a routine method of dealing with a variety of lesions. The level of interest in the neurosurgical surgery community is reflected by the geometric expansion of contributions to the literature on endoscopic surgery.
Abstract
OBJECTIVE:
The aim of the present study was to compare the anatomy of the cavernous sinus via an endoscopic transnasal route with the anatomy of the same region explored by the transcranial ...route. The purpose was to identify and correlate the corresponding anatomic landmarks both through the endoscopic transnasal transsphenoidal and the microscopic transcranial views.
METHODS:
Five fresh injected heads (10 specimens) were dissected by the endoscopic transnasal and microsurgical transcranial approaches. A comparison of different microsurgical corridors of the cavernous sinus with the corresponding endoscopic transnasal ones was performed.
RESULTS:
Through the endoscopic transnasal approach, it is possible to explore only some of the parasellar and middle cranial fossa subregions. Because of the complex multilevel architecture of the cavernous sinus, there is not always a correspondence between the surgical corridors bounded through the transcranial route and those exposed through the endoscopic transnasal approach. Nevertheless, some surgical corridors specific to the endoscopic transnasal route are evident: a C-shaped corridor is identifiable medial to the “intracavernous” internal carotid artery, whereas a wider triangular area is delineable lateral to the internal carotid artery; inside the latter, three more surgical corridors (a superior triangular space, a superior quadrangular space, and an inferior quadrangular space) can be described.
CONCLUSION:
Different surgical corridors can be defined during the endoscopic transnasal approach to the anteroinferior portion of the cavernous sinus, as already established for the transcranial route as well. Knowledge of these could be useful in decreasing morbidity and mortality during surgery in this region, these approaches being reserved to experienced transsphenoidal surgeons only.
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