Enrico de Divitiis

Endoscopic Transsphenoidal Approach: Adaptability of the Procedure to Different Sellar Lesions

OBJECTIVE To demonstrate the flexibility of the endoscopic transsphenoidal approach, with respect to nasal and paranasal anatomic features and the extension of different sellar lesions, for customization of the procedure for specific conditions. METHODS In 16 of 170 consecutive endoscopic transsphenoidal operations, some modifications of the standard approach were adopted to optimize surgical removal of different lesions. These modifications consisted of a hemisphenoidotomy, a partial ethmoidectomy, extended sellar floor opening toward the planum sphenoidale or the clivus, enlarged opening of the sphenoid ostium area with ipsilateral removal of the superior turbinate, and a bilateral approach. RESULTS The endoscopic endonasal procedure is easily adaptable to different specific conditions, with slight changes in the standard approach (more or less invasive). Therefore, this surgical procedure is satisfactory for different lesion locations and for the nasal and paranasal sinus anatomic features of individual patients. CONCLUSION The endoscopic surgical route should be tailored to different sellar lesions, and some modifications of the procedure are recommended in selected cases.

Extended endoscopic endonasal transsphenoidal approach for the removal of suprasellar tumors: Part 2.

OBJECTIVEThe widespread use of the endoscope in transsphenoidal pituitary surgery has recently contributed to the extension of the approach beyond the tuberculum sellae and planum sphenoidale for the management of lesions located in the suprasellar area, either with an endoscope-assisted or purely endoscopic technique. Based on our previous experience with more than 450 standard endoscopic transsphenoidal operations, we have retrospectively evaluated the effectiveness of the extended endoscopic endonasal transsphenoidal approach in the management of lesions mainly located in the suprasellar area. METHODSBetween January 2004 and December 2005, 20 consecutive patients underwent extended endoscopic endonasal transsphenoidal surgery for a total of 21 procedures. The series consisted of seven pituitary adenomas, seven craniopharyngiomas, three suprasellar Rathkes cleft cysts, two tuberculum sellae meningiomas, and one pilocytic astrocytoma of the chiasm. RESULTSTumor removal, as assessed by postoperative magnetic resonance imaging, revealed complete removal of the lesion in four out of seven pituitary adenomas, five out of seven craniopharyngiomas, three out of three Rathkes cleft cysts, and two out of two tuberculum sellae meningiomas. One patient (5%) with craniopharyngioma had a postoperative cerebrospinal fluid leak that required reoperation. The same patient experienced a sphenoid mycosis, which was treated with medical therapy. Some specific conditions associated with the anatomy of the surgical route, as well as to the morphology of the lesion, have resulted to condition the feasibility of the approach. CONCLUSIONSmall and medium sized suprasellar lesions located in the midline, with or without a limited parasellar extension and without involvement of vascular structures, seem amenable to be resected through such extended endoscopic transsphenoidal approach. Improvements in closure techniques and the use of new materials and surgical glues seem to significantly reduce the postoperative cerebrospinal fluid leak rate and meningitis.

Extended endoscopic transsphenoidal approach for tuberculum sellae meningiomas.

OBJECTIVE 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. PATIENTS AND METHODS 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. RESULTS 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. CONCLUSION 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.

Tuberculum sellae meningiomas: high route or low route? A series of 51 consecutive cases.

OBJECTIVETuberculum sellae meningiomas represent 5 to 10% of all intracranial meningiomas. Such lesions are classically removed through a variety of well-standardized transcranial approaches. The extended endonasal transsphenoidal route, under either microscopic or endoscopic visualization, has only recently been proposed as a viable surgical technique for the management of such tumors. MATERIAL AND METHODSA total of 51 consecutive patients with tuberculum sellae meningiomas were treated at our institution during a 21-year period. Forty-four patients had transcranial surgery, and the last seven were treated via the extended endoscopic transsphenoidal approach. We also compared our data with those reported in the pertinent literature related to the surgical, ophthalmological, and endocrinological outcome. RESULTSThe significant difference among the transcranial and transsphenoidal series, both in our experience and in the reviewed literature, did not allow us to draw statistically significant results but rather a reporting of the outcomes. In the transcranial group, 86.4% had a gross total removal of the lesion, whereas the percentage was 83.3% in the transsphenoidal group. Concerning the visual outcome, we experienced postoperative improvement in 61.4% of the transcranial patients and a worsening of 13.6%, whereas improvement was reported in 71.4% of the patients in the transsphenoidal group; in the last group, we did not observe any postoperative worsening. The main drawback of the transsphenoidal approach still remains the difficulty in reconstructing the cranial base dural and bone defects, which expose patients to a greater risk of postoperative cerebrospinal fluid leakage (28.6% in our series) and related complications. CONCLUSIONWhen treating a patient with a diagnosis of tuberculum sellae meningioma, a neurosurgeon should know that, aside from the classical transcranial approach, the possibility of an extended transsphenoidal approach exists. Although it is still not a standardized procedure, in carefully selected cases (i.e., small midline lesions, without major vessel encasement, or parasellar extension) and in experienced hands, it could be considered a viable alternative, especially in overcoming the reconstruction-related problems.

Sellar repair in endoscopic endonasal transsphenoidal surgery: results of 170 cases.

OBJECTIVETo describe techniques and materials used in sellar repair after an endoscopic endonasal transsphenoidal approach. METHODSDifferent techniques of sellar closure and indications for each specific condition are reviewed in a series of 170 consecutive patients. RESULTSOnly 47 (27.6%) of 170 patients were considered candidates for sellar reconstruction after the endoscopic operation, mainly because of intraoperative cerebrospinal fluid leaks (14.1%). The overall rate of postoperative cerebrospinal fluid leakage was 2.3%, which was cured by means of an early reoperation in three cases and with lumbar drainage in the fourth case. CONCLUSIONReconstruction of the sella was considered necessary in only one-third of the patients who underwent operations via an endoscopic transsphenoidal procedure. Some minor expedients can be useful for the reconstruction, and the ideal material for the repair should be chosen.

Skull base reconstruction in the extended endoscopic transsphenoidal approach for suprasellar lesions

OBJECT 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. METHODS 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. RESULTS 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. CONCLUSIONS 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.

Endoscopic transnasal approach to the cavernous sinus versus transcranial route: anatomic study.

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.

Endoscopic third ventriculostomy in idiopathic normal pressure hydrocephalus.

OBJECTIVE:To define the role and indications for an endoscopic third ventriculostomy (ETV) in patients with idiopathic normal pressure hydrocephalus (INPH). A series of 25 patients treated by endoscopic technique was analyzed, and the results were compared with those of 14 studies reporting patients treated by shunting. METHODS:Twenty-five patients with INPH were treated by ETV from January 1994 through December 2000. All were younger than 75 years of age, had a preoperative clinical history of 1 year or less, had prevalence of gait disturbance with scarce or mild dementia, had marked ventricular enlargement on magnetic resonance imaging (MRI), and had intracranial pressure values ranging from 8 to 12 mm Hg. All were studied by a phase-contrast MRI flow study 1 month after ETV. The 14 reviewed series of patients treated by shunting (all published after 1980) each include more than 25 patients, for a total of 777 patients. RESULTS:The overall rate of neurological improvement after ETV in our series was 72% (including two patients reoperated on because of absence of flow in the MRI scan); this percentage is slightly higher than that found in the 14 series of shunted patients (66%). Gait disturbance showed a high rate of improvement when compared with other symptoms, both in our ETV study and in other shunting series. Postoperative complications occurred only in one patient (4%) with an intracerebral frontal hemorrhage and in 37.9% of patients from the series including shunted patients. CONCLUSION:In patients with INPH showing short duration of symptoms, prevalence of gait disturbance, and slight mental impairment, ETV provides similar results to those of shunting. We suggest performing ETV in these patients and reserving shunting only for those who do not improve after ETV, despite the presence of cerebrospinal fluid flow through the ventriculostomy on MRI flow studies. The good results after ETV in our series indirectly confirm that the cerebrospinal fluid absorption is good or at least sufficient in selected patients with INPH.

Recurrences of meningiomas: predictive value of pathological features and hormonal and growth factors

SummaryObjectiveRecurrence 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.MethodsTwo 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.ResultsThe 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.ConclusionsHigher 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.

Posterior fossa hemangioblastomas

The authors report 40 personal cases of infratentorial hemangioblastomas and review 36 series from the literature for a total number of 1023 patients. The clinical, pathological, and surgical features of these tumors are discussed, with particular consideration of localizations outside the nervous system, multicentric tumors, recurrences, and long-term results. Although hemangioblastomas are benign tumors, their high growth potential makes their long-term development unpredictable in some cases.