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Luigi Maria Cavallo

Publications and source records attributed to Luigi Maria Cavallo.

12 recordsLinked to original sources

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

OBJECTIVE: The 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. METHODS: Between 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 Rathke's cleft cysts, two tuberculum sellae meningiomas, and one pilocytic astrocytoma of the chiasm. RESULTS: Tumor 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 Rathke's 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. CONCLUSION: Small 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.

Adult↗

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.

Cadaver↗

Current state and future development of intracranial neuroendoscopic surgery.

Since the introduction of the modern, smaller endoscopes in the 1960s, neuroendoscopy has become an expanding field of neurosurgery. Neuroendoscopy reflects the tendency of modern neurosurgery to aim towards minimalism; that is, access and visualization through the narrowest practical corridor and maximum effective action at the target point with minimal disruption of normal tissue. Transventricular neuroendoscopy allows the treatment of several pathologies inside the ventricular system, such as obstructive hydrocephalus and intra-/paraventricular tumors or cysts, often avoiding the implantation of extracranial shunts or more invasive craniotomic approaches. Endoscopic endonasal transphenoidal surgery allows the treatment of pathologies of the sellar and parasellar region, with the advantage of a wider vision of the surgical field, less traumatism of the nasal structures, greater facility in the treatment of possible recurrences and reduced complications. However, an endoscope may be used to assist microsurgery in virtually any kind of neurosurgical procedures (endoscope-assisted microsurgery), particularly in aneurysm and tumor surgery. Basic principles of optical imaging and the physics of optic fibers are discussed, focusing on the neuroendoscope. The three main chapters of neuroendoscopy (transventricular, endonasal transphenoidal and endoscope-assisted microsurgery) are reviewed, concerning operative instruments, surgical procedures, main indications and results.

Brain↗

Endoscopic endonasal transsphenoidal surgery: procedure, endoscopic equipment and instrumentation.

INTRODUCTION: In the last 10 years the endoscopic endonasal transsphenoidal approach has been proposed as a minimally invasive procedure for the treatment of pathologies of the sellar region. This procedure introduces various advantages compared with the transsphenoidal microsurgical approach such as a wider vision of the surgical field, less traumatism of the nasal structures, greater facility in the treatment of possible recurrences, and reduced complications. Nevertheless, as for any new procedure, there is an initial learning curve that is somewhat steep, due to the necessity of acquiring the specific endoscopic skills. It is equally essential to be supplied with dedicated endoscopic equipment and appropriate surgical instrumentation, in order to optimize the different stages of the operation. DISCUSSION: Therefore, after our extensive experience with over 250 patients treated by means of the endoscopic endonasal transsphenoidal approach for pathologies of the sellar region, we describe herein the characteristics of the proper endoscopic instrumentation, as well as a set of surgical instruments intentionally conceived to respond to the specific characteristics of this new procedure.

Endoscopy↗

Sellar repair with fibrin sealant and collagen fleece after endoscopic endonasal transsphenoidal surgery.

OBJECTIVE: To determine, in patients undergoing sellar repair after endoscopic endonasal transsphenoidal surgery, the clinical efficacy of a combination of fibrin sealant/collagen fleece compared to the use of fibrin sealant or collagen fleece alone, in preventing CSF-related (cerebrospinal fluid) postoperative complications. METHODS: From a retrospective analysis of our series of 242 consecutive endoscopic transsphenoidal procedures, in 56 out of the 90 cases in which the sella had been repaired, fibrin sealant and/or collagen fleece was employed, both in combination with one or multiple layers of other materials. The incidence of postoperative CSF leaks and the need for a postoperative lumbar drainage in the groups of fibrin sealant or collagen fleece treated patients were compared to the group of patients treated with the fibrin sealant/collagen fleece combination. RESULTS: In 2 out of 16 fibrin sealant treated patients a postoperative CSF leak presented, and in 6 out of these 16 subjects a postoperative lumbar drainage was necessary; patients who received a fibrin sealant/collagen fleece combination exhibited no detectable postoperative CSF leak, and no postoperative lumbar drainage was used. CONCLUSIONS: Closure of the sella turcica with fibrin sealant in combination with a collagen fleece is a safe and effective method to prevent CSF fistulas. When used in combination, the collagen fleece enhances the sealing and tissue regeneration properties of the fibrin sealant, thus reducing the incidence of postoperative CSF leaks, obviating the need for a lumbar drain placement.

Collagen↗

Endoscopic endonasal transsphenoidal surgery.

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.

Adenoma↗

One-stage removal of residual intracanalicular acoustic neuroma and hemihypoglossal-intratemporal facial nerve anastomosis: technical note.

OBJECTIVE AND IMPORTANCE: Incomplete removal of residual intracanalicular tumor and injury to the facial nerve are the main problems associated with surgery of large acoustic neuromas via the retromastoid suboccipital approach. In patients with residual or recurrent intracanalicular neuromas, the translabyrinthine approach is the preferred surgical route, allowing complete tumor removal; it may eventually also be used for exposure of the intratemporal portion of the facial nerve for a hemihypoglossal-facial nerve anastomosis when a postoperative facial palsy exists This one-stage procedure has not been described previously. CLINICAL PRESENTATION: Three patients with postoperative facial palsy and residual intracanalicular tumor after surgical removal of a large acoustic neuroma via the retromastoid suboccipital approach underwent reoperation via the translabyrinthine approach and one-stage removal of the residual tumor and hemihypoglossal-facial nerve anastomosis. All three patients had a complete facial palsy of House-Brackmann Grade VI and a residual tumor of 8 to 12 mm. TECHNIQUE: A classic translabyrinthine approach was used to open the internal auditory canal and remove the residual intracanalicular tumor. The facial nerve was exposed in its mastoid and tympanic parts, mobilized, and transected; then, the long nerve stump was transposed into the neck and used for an end-to-side anastomosis into the hypoglossal nerve. The operation resulted in variable improvement of the facial muscle function up to Grade III (one patient) and Grade IV (two patients). CONCLUSION: Reoperation via the translabyrinthine approach is indicated for removal of residual intracanalicular acoustic neuroma and realization of a hypoglossal-facial nerve anastomosis in a single procedure. It is suggested that this type of anastomosis may also be used during the initial operation for acoustic neuroma removal when the facial nerve is inadvertently sectioned.

Anastomosis, Surgical↗

Endoscopic examination of the cerebellar pontine angle.

This anatomic study describes how to optimize the use of the endoscope in the cerebellar pontine angle (CPA) through a retrosigmoid approach. Unlike the microscope, that only permits visualization of structures directly ahead, the endoscope can see 'around the corner', also showing the structures down narrow. Nevertheless, to use the endoscope it is necessary to insert it into the CPA that is full of neurovascular structures which limit its movements. Thus, to avoid damages it is important to inspect this region accurately, by means of preferential trajectories to insert the endoscope. A retrosigmoid approach was performed in cadaver heads, and the CPA region was inspected employing 0 degrees, 45 degrees rigid endoscopes (4 mm in diameter). The neurovascular structures of the CPA have been visualized using three trajectories. The limits of view offered by each trajectory as well as the neurovascular structures together with the obstacles encountered on each route have been described. The systematic adoption of three different endoscope trajectories at the CPA level permits to view from different angulation the same structure as well as its relationships with the surrounding nerves and vessels. Considerable experience on cadavers should have already been obtained with the endoscope prior to any application in the operating room.

Anthropometry↗

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.

Adenoma↗

Surgical complications associated with the endoscopic endonasal transsphenoidal approach for pituitary adenomas.

OBJECT: To assess postoperative complications related to the surgical procedure, a retrospective analysis was conducted in a series of 146 consecutively treated patients who underwent an endoscopic endonasal transsphenoidal approach to the sellar region for resection of pituitary adenomas between January 1997 and July 2001. METHODS: Complications were divided into groups (nasofacial, sphenoid sinus, sella turcica, supra or parasellar, and endocrine complications) according to the anatomical structures and the systems involved. Overall, a decreased incidence of complications has been observed, compared with large historical series of the traditional microsurgical transsphenoidal approach, likely because of the overview inside the anatomy facilitated by the endoscope, and the decreased surgical trauma. CONCLUSIONS: Transsphenoidal surgery, either microscopic or endoscopic, is a safe procedure in experienced hands, but serious complications still occur and must be reduced as much as possible. Additional improvement can be expected with greater experience and new technical developments. A coordinated team effort with other dedicated colleagues from different specialties is advised.

Adenoma↗

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

OBJECTIVE: To describe techniques and materials used in sellar repair after an endoscopic endonasal transsphenoidal approach. METHODS: Different techniques of sellar closure and indications for each specific condition are reviewed in a series of 170 consecutive patients. RESULTS: Only 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. CONCLUSION: Reconstruction 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.

Adenoma↗