Aldo Cassol Stamm

Endoscopic Transnasal Craniotomy and the Resection of Craniopharyngioma

Objectives/Hypothesis: To describe the utility of a large transnasal craniotomy and its reconstruction in the surgical management of patients with craniopharyngioma.

Closure of large skull base defects after endoscopic transnasal craniotomy. Clinical article.

OBJECT The authors describe the utility of and outcomes after endoscopic transnasal craniotomy and skull reconstruction in the management of skull base pathologies. METHODS The authors conducted a observational study of patients undergoing totally endoscopic, transnasal, transdural surgery. The patients included in the study underwent treatment over a 12-month period at 2 tertiary medical centers. The pathological entity, region of the ventral skull base resected, and size of the dural defect were recorded. Approach-related complications were documented, as well as CSF leaks, infections, bleeding-related complications, and any minor complications. RESULTS Thirty consecutive patients were assessed during the study period. The patients had a mean age of 45.5 +/- 20.2 years and a mean follow-up period of 182.4 +/- 97.5 days. The dural defects reconstructed were as large as 5.5 cm (mean 2.49 +/- 1.36 cm). One patient (3.3%) had a CSF leak that was managed endoscopically. Two patients had epistaxis that required further care, but there were no complications related to intracranial infections or bleeding. Some minor sinonasal complications occurred. CONCLUSIONS Skull base endoscopic reconstructive techniques have significantly advanced in the past decade. The use of pedicled mucosal flaps in the reconstruction of large dural defects resulting from an endoscopic transnasal craniotomy permits a robust repair. The CSF leak rate in this study is comparable to that achieved in open approaches. The ability to manage the skull base defects successfully with this approach greatly increases the utility of transnasal endoscopic surgery.

Endoscopic management of spontaneous meningoencephalocele of the lateral sphenoid sinus.

OBJECT Spontaneous meningoencephaloceles of the lateral sphenoid sinus are rare lesions that are hypothesized to result from persistence of the lateral craniopharyngeal canal. Prior reports of the management of this lesion have been limited by its relative rarity. The objective of this paper is to report the theoretical etiology, surgical technique, and outcomes in patients undergoing endoscopic repair of spontaneous meningoencephalocele of the sphenoid sinus. METHODS The authors conducted a retrospective review of a multiinstitutional series of 13 cases involving patients who underwent endoscopic repair of spontaneous meningoencephalocele of the lateral sphenoid sinus. The surgical technique and pathophysiological considerations are discussed. RESULTS The clinical manifestations included CSF rhinorrhea (85%), chronic headache (77%), and a history of meningitis (15%). The endoscopic approaches to the lateral sphenoid sinus were transnasal (39%), transpterygoid (23%), and transethmoid (39%). Two patients (8%) had postoperative CSF leaks, one of which closed spontaneously and one of which required revision endoscopic closure. All patients were free of leak at most recent follow-up. One patient experienced postoperative meningitis in the early postoperative period. CONCLUSIONS Endoscopic endonasal closure is an effective modality in the treatment of spontaneous meningoencephaloceles of the lateral sphenoid sinus. If the sphenoid sinus has extensive lateral pneumatization, adequate exposure may require a transpterygoid approach.

Malignant external otitis in infants

The authors report two cases of malignant external otitis in infant boys, 5 and 6 months old respectively, caused by different etiologic agents (Pseudomonas aeruginosa and Proteus mirabilis). Both of them were in very poor general health, but neither developed complications such as facial paralysis because of the intensive treatment that was employed from the beginning.

Building a real endoscopic sinus and skull-base surgery simulator.

Endoscopic sinus and skull base surgery (ESSS) is considered the “gold standard” for the treatment of many lesions of the nose, paranasal sinus, and adjacent structures. The manipulation of instruments during these procedures is challenging because of the complex anatomy and proximity to important structures such as the brain, orbital content, carotid arteries, and optic nerve, among others. Long periods of training are traditionally necessary in order to perform safe and adequate ESSS. Resident training includes anatomic lectures, a video session, cadaver dissection, direct observation of surgeries, and the realization of ESSS supervised by experienced doctors. Unfortunately, in some training hospitals, this process has been impaired by the restricted number of procedures and more difficult dissection pieces. In order to fulfill this problem, virtual simulators have been developed. These simulators use virtual-reality concepts and direct interaction mechanisms with users, such as simulation of force and feedback of touch sensation on specific structures. Unfortunately, these virtual models have some disadvantages, such as the high cost of the equipment, the use of computer-generated virtual images, some with low resolution, and touch-sensitive alterations in some structures. In addition, they do not allow the use of real instruments used on ESSS. There is a general consensus that the size and complexity of the structures in the nose and paranasal sinus are a major problem in the development and construction of a realsimulation model for ESSS. We show the development of a real model for training ESSS that allows the use of the same endoscopes and instruments used on real nasal procedures, discussing its steps, materials, and technical difficulties.

Orbital cavernous hemangioma: transnasal endoscopic management.

Cavernous hemangiomas (CHs) are the most common intraorbital tumors found in adults. Although histologically benign, they can encroach on intraorbital or adjacent structures and be considered anatomically or positionally malignant. Most of these tumors are unilateral and can increase intraorbital volume with a resultant mass effect. Visual acuity or field compromise, diplopia, and extraocular muscle or pupillary dysfunction can result from compression of intraorbital contents. The morbidity associated with orbital CH is the threat of compressive optic neuropathy, extraocular muscle dysfunction, and cosmetic disfigurement. Most orbital CHs require no intervention, but especially when there is visual compromise, surgery is indicated. The approach is dictated by tumor location within the orbit. The typical described approaches are lateral orbitotomy, transconjunctival, and frontotemporal. We present a case of an orbital CH with visual compromise and its transnasal endoscopic surgical management. A 33-year-old male presented with a six-month history of a progressive left visual loss that had worsened during the last month. He did not present with proptosis, eye movement limitations, or any other complaints. After a complete ophthalmologic evaluation, he performed an eye campimetry that showed severe decrease of left visual acuity. An MRI showed an intraorbital mass that filled up homogeneously on gadolinium, at the left orbital apex, with approximately 8 mm on its largest axis, compressing the left orbital nerve, and with close relationship with extraocular muscles (Fig 1). After a careful preoperative evaluation with CT to analyze the orbital cavity and its relationship with the paranasal sinus, and an arteriography to analyze the blood vessel supply to the tumor, an endoscopic transnasal resection of the lesion was proposed. After IRB approval and the patient’s informed consent, the surgery was performed. A left maxillary antrostomy and a complete left ethmoidectomy were performed. The left

A novel approach allowing binostril work to the sphenoid sinus

Surgical approaches to the sphenoid sinus began in the early 20th century as sellar tumors gained recognition because of advances in neurology, pathology, and radiology. Developments in the field of endoscopic surgery have prompted surgeons to attempt endoscope-assisted surgery of the pituitary gland and to use endoscopes in surgery for pituitary tumors and anterior skull base lesions, which have been particularly successful. 1 Access to the sphenoid sinus is the first step in surgery and classically has been described in three ways: transnasal direct, transseptal, and transnasal with removal of the posterior nasal septum. The transnasal direct is preferable when the lesion is unilateral. The transseptal approach is more conservative and leaves the anatomy of the nasal cavity intact. The transnasal approach with removal of the posterior nasal septum may be preferable when the patient has undergone previous septum surgery; this approach also allows concomitant binostril work. 2-4 However, to enable the binostril work, the posterior septal portion must be removed, a procedure that results in a large posterior septal perforation. Septal perforations can cause significant morbidity; associated symptoms include nasal congestion or obstruction, nasal crusting and drainage, and recurrent epistaxis, among other problems. We describe a novel endoscopic transseptal approach using a posterior nasal septal mucosal flap, which allows the surgeon to perform binostril work, cover the skull base defects, and avoid posterior nasal septal perforation. This technique was submitted to and approved by the ethical committee of our institution. SURGICAL TECHNIQUE The surgery is performed under general anesthesia. The patient is in the supine position, with the dorsum elevated approximately 30 degrees. The nasal cavity is decongested with cottonoids soaked in a vasoconstrictor solution. The surgery begins with an infiltration of the nasal septum with a lidocaine 2 percent epinephrine 1:100.000 solution. A classic anterior incision for septoplasty is made, generally at the right side of the nose. A mucoperichondrial/ mucoperiosteal dissection is made at both sides. The posterior part of the nasal septum is removed, saving the inferior portion as a landmark for midline. The sphenoid rostrum and anterior wall of the sphenoid sinus are exposed. The next step is the creation of the flap at one side of the nasal septal mucosa. We perform three incisions: 1) vertical: 2 to 3 cm anterior to the sphenoid rostrum; 2) superior horizontal: 1 to 2 cm below the most superior aspect of the nasal septum; 3) inferior horizontal: 0.5 cm above the nasal floor. These incisions can be completed with scissors or other sharp instruments as necessary, making a mucosal flap that is displaced on the nasal floor (Fig 1). This nasal septal flap preserves the posteriolateral neurovascular pedicle in the sphenopalatine neurovascular bundle. 5 The other side of the

Nasal septal cross-over flap technique: a choanal atresia micro-endoscopic surgical repair.

Choanal atresia is a congenital malformation of the posterior portion of the nasal cavity, which is usually unilateral. The incidence is estimated to be 1 in 5,000 to 8,000 live births. Several surgical approaches have been described to correct choanal atresia since Emmerts initial trocar perforation in 1853, including transnasal, transpalatal, transseptal, sublabial transseptal, transantral, and external rhinoplasty. Although the micro-endoscopic transnasal access is a more conservative technique, it allows greater surgical precision, and is currently recommended by many authors; choanal atresia repair is still considered a challenge, with risks of intraoperative and postoperative complications and re-stenosis. This paper reports the results of a series of 33 patients operated via the transnasal micro-endoscopic surgical approach, and describes a new endoscopic technique that the authors call “nasal septal cross-over flap technique.”

Evolution of endoscopic skull base surgery, current concepts, and future perspectives.

Endoscopic techniques have influenced almost all of the surgical specialties. From open procedures to minimally invasive approaches, the endoscope and its ability to reach areas within the human body has gained popularity among specialists, creating a revolution in some fields. Two of the fields in which endoscopes provided a true revolution are otolaryngology and neurosurgery. The authors discuss some important factors for the evolution of endoscopic skull base surgery and expanded endonasal approaches, highlighting historical landmarks but also addressing the current concepts, complications, and the future of this promising field for clinical research and surgical techniques and technology.

The Endoscopic Endonasal Approach for Extradural and Intradural Clivus Lesions

OBJECTIVE To report the use of the endoscopic transnasal transclival approach to treat tumors involving the clivus region. METHODS The clinical records of 38 patients with clivus lesions were retrospectively reviewed to determine the surgical technique used. All patients were surgically treated using any of the options of the endoscopic transnasal transclival approach at the São Paulo Skull Base Center from 2000-2011. A transsphenoidal, transpterygoidal, retropharyngeal, or a combination of approaches was chosen based on the tumor topography. RESULTS Chordomas were the most frequent tumor (26 of 38), followed by chondrosarcoma (2 of 38). Biopsy only was performed in 6 patients with metastasis to the clivus, and 1 patient with fibrous dysplasia underwent a planned partial resection. Gross total resection (GTR) was achieved in 15 of 31 (48%) patients with indications for GTR. For centrally located tumors, GTR was achieved in 75% (15 of 20 patients). Fistula was the most frequent complication (6 of 31; 19%) but was much lower in the most recent series using the nasoseptal flap (1 of 16; 6%). Tumors with lateral extensions or with previous treatment had the worst results. The presence of intradural extension was not a limiting factor for GTR. CONCLUSION Endoscopic transnasal surgery is an alternative approach to treatment of clivus lesions, and, in expert hands, this technique can obtain good results. Lateral extension and previous treatment were factors that could make the surgery more difficult. Intradural extension did not limit the radicality of the removal.