Ricardo L. L. Dolci

Endoscopic Endonasal Approach for Removal of Tuberculum Sellae Meningiomas

Tuberculum sellae meningiomas are challenging lesions; their critical location and often insidious growth rate enables significant distortion of the superjacent optic apparatus before the patient notices any visual impairment. This article describes the technical nuances, selection criteria and complication avoidance strategies for the endonasal resection of tuberculum sellae meningiomas. A stepwise description of the surgical technique is presented; indications, adjuvant technologies, pitfalls and the relevant anatomy are also reviewed. Tuberculum sellae meningiomas may be safely and effectively resected through the endonasal route; invasion of the optic canals does not represent a limitation.

Postoperative otorhinolaryngologic complications in transnasal endoscopic surgery to access the skull base.

INTRODUCTION The large increase in the number of transnasal endoscopic skull base surgeries is a consequence of greater knowledge of the anatomic region, the development of specific materials and instruments, and especially the use of the nasoseptal flap as a barrier between the sinus tract (contaminated cavity) and the subarachnoid space (sterile area), reducing the high risk of contamination. OBJECTIVE To assess the otorhinolaryngologic complications in patients undergoing endoscopic surgery of the skull base, in which a nasoseptal flap was used. METHODS This was a retrospective study that included patients who underwent endoscopic skull base surgery with creation of a nasoseptal flap, assessing for the presence of the following post-surgical complications: cerebrospinal fluid leak, meningitis, mucocele formation, nasal synechia, septal perforation (prior to posterior septectomy), internal nasal valve failure, epistaxis, and olfactory alterations. RESULTS The study assessed 41 patients undergoing surgery. Of these, 35 had pituitary adenomas (macro- or micro-adenomas; sellar and suprasellar extension), three had meningiomas (two tuberculum sellae and one olfactory groove), two had craniopharyngiomas, and one had an intracranial abscess. The complications were cerebrospinal fluid leak (three patients; 7.3%), meningitis (three patients; 7.3%), nasal fossa synechia (eight patients; 19.5%), internal nasal valve failure (six patients; 14.6%), and complaints of worsening of the sense of smell (16 patients; 39%). The olfactory test showed anosmia or hyposmia in ten patients (24.3%). No patient had mucocele, epistaxis, or septal perforation. CONCLUSION The use of the nasoseptal flap has revolutionized endoscopic skull base surgery, making the procedures more effective and with lower morbidity compared to the traditional route. However, although mainly transient nasal morbidities were observed, in some cases, permanent hyposmia and anosmia resulted. An improvement in this technique is therefore necessary to provide a better quality of life for the patient, reducing potential complications.

The Endoscopic Endonasal Approach for Removal of Petroclival Chondrosarcomas

Chondrosarcomas of the skull base are rare, locally invasive tumors that typically arise in the petroclival region, from degenerated chondroid cells located within the synchondrosis. Given their usually slow growth rate, they are capable of reaching sizable dimensions, promoting bone erosion and significant displacement of neurovascular structures before causing symptomatology that will eventually lead to diagnosis; cranial neuropathies and headaches are common complaints. This article discusses the pertinent surgical anatomy, patient selection criteria, technical nuances and complication management of the endonasal resection of skull base chondrosarcomas.

Effect of Incremental Endoscopic Maxillectomy on Surgical Exposure of the Pterygopalatine and Infratemporal Fossae

Objective Access to the pterygopalatine and infratemporal fossae presents a significant surgical challenge, owing to their deep-seated location and complex neurovascular anatomy. This study elucidates the benefits of incremental medial maxillectomies to access this region. We compared access to the medial aspect of the infratemporal fossa provided by medial maxillectomy, anteriorly extended medial maxillectomy, endoscopic Denker approach (i.e., Sturmann-Canfield approach), contralateral transseptal approach, and the sublabial anterior maxillotomy (SAM). Methods We studied 10 cadaveric specimens (20 sides) dissecting the pterygopalatine and infratemporal fossae bilaterally. Radius of access was calculated using a navigation probe aligned with the endoscopic line of sight. Area of exposure was calculated as the area removed from the posterior wall of maxillary sinus. Surgical freedom was calculated by computing the working area at the proximal end of the instrument with the distal end fixed at a target. Results The endoscopic Denker approach offered a superior area of exposure (8.46 ± 1.56 cm(2)) and superior surgical freedom. Degree of lateral access with the SAM approach was similar to that of the Denker. Conclusion Our study suggests that an anterior extension of the medial maxillectomy or a cross-court approach increases both the area of exposure and surgical freedom. Further increases can be seen upon progression to a Denker approach.

Endoscopic endonasal study of the cavernous sinus and quadrangular space: Anatomic relationships.

The quadrangular space permits an anterior entry into Meckels cave while obviating the need for cerebral or cranial nerve retraction. This avenue is intimately associated with the cavernous sinus; thus, from this ventral perspective, it is feasible to visualize the anteromedial, anterolateral, and Parkinson triangles.

Possible esthesioneuroblastoma metastasis to paranasal sinuses: Clinical report and literature review

Local recurrence, and regional and distant metastases, respectively, develop in 30% and 15% of patients with esthesioneuroblastoma (ENB).

Endoscopic endonasal anatomical study of the cavernous sinus segment of the ophthalmic nerve.

This cadaveric study analyzes the endoscopic endonasal anatomy of the ophthalmic division of the trigeminal nerve (V1), from the middle fossa to its orbital entry via the superior orbital fissure. Anatomical relationships with the surrounding cranial nerves and blood vessels are described, with emphasis on their clinical correlation during surgery in this region. Our objective was to describe the anatomical relationships of the ophthalmic division of the trigeminal nerve.

Periodic olfactory assessment in patients undergoing skull base surgery with preservation of the olfactory strip

Others have reported olfactory disturbances following endoscopic approaches to the skull base. However, there is a lack of consensus on the extent and duration of dysfunction. This study aimed to compare our results with previously published work and to validate the olfactory strip–sparing approach.

Endoscopic endonasal anterior maxillotomy

INTRODUCTION The last few decades have witnessed radical changes in the management of pathologic processes of the sinonasal cavity. Endoscopy precipitated a paradigm shift in the diagnostic and surgical approach to lesions in the paranasal sinuses and skull base. A better understanding of the surgical anatomy, aided by the superior visualization of the endoscope catapulted the design and adoption of minimally invasive techniques. This is exemplified by the transition from medial maxillectomy via transfacial incisions (i.e., lateral rhinotomy) to a completely endoscopic approach. Another notable example is that of the Caldwell-Luc procedure, which was widely performed in the last century, yet has fallen out of favor owing to its relatively high incidence of complications and the successful treatment of sinonasal diseases, either by current medical management or by safer and less invasive endoscopic sinus surgery. However, access to the anterior half of the maxillary sinus is challenging, even with the use of a 45 and 70 rod-lens endoscope and angled instruments. The anterior half of the maxillary sinus has been traditionally accessed sublabially by way of a canine fossa puncture or an anterior maxillotomy. There is abundant literature discussing the advantages, disadvantages, and potential complications associated with these procedures, and therefore the need for various technical modifications. This study describes an alternative technique for performing an endonasal anterior maxillotomy, thus obviating the need for a separate sublabial incision. Endoscopic endonasal anterior maxillotomy is a versatile technique, and the size and site of the maxillotomy can be modified according to the course of the anterosuperior alveolar nerve to minimize the possibility of damage.

Anatomical nuances of the internal carotid artery in relation to the quadrangular space

OBJECTIVE The aim of this study was to evaluate the anatomical variations of the internal carotid artery (ICA) in relation to the quadrangular space (QS) and to propose a classification system based on the results. METHODS A total of 44 human cadaveric specimens were dissected endonasally under direct endoscopic visualization. During the dissection, the anatomical variations of the ICA and their relationship with the QS were noted. RESULTS The space between the paraclival ICAs (i.e., intercarotid space) can be classified as 1 of 3 different shapes (i.e., trapezoid, square, or hourglass) based on the trajectory of the ICAs. The ICA trajectories also directly influence the volumetric area of the QS. Based on its geometry, the QS was classified as one of the following: 1) Type A has the smallest QS area and is associated with a trapezoid intercarotid space, 2) Type B corresponds to the expected QS area (not minimized or enlarged) and is associated with a square intercarotid space, and 3) Type C has the largest QS area and is associated with an hourglass intercarotid space. CONCLUSIONS The different trajectories of the ICAs can modify the area of the QS and may be an essential parameter to consider for preoperative planning and defining the most appropriate corridor to reach Meckels cave. In addition, ICA trajectories should be considered prior to surgery to avoid injuring the vessels.