Paulo M. Mesquita Filho

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.

Optic Canal Decompression: Comparison of 2 Surgical Techniques

BACKGROUND The optic canal is a bony channel that connects the anterior cranial fossa and orbit and contains the optic nerve and ophthalmic artery. It can be affected by several pathologies, leading to compression of the nerve nearby or inside the canal, leading to visual impairment. The usual technique to decompress the canal is through a craniotomy, but recently endoscopic endonasal approaches (EEAs) have surfaced as an interesting alternative due to direct access to the canal without the need for manipulation of neurovascular structures. METHODS Six specimens were dissected. The right optic canal was drilled on the right side via the EEA, and the left optic canal was drilled via frontotemporal craniotomy. The amount of decompression was measured using a 3-dimensional reconstruction on computed tomography scans and compared. RESULTS The EEA generated an average of 267.8 (221-294) degrees of decompression in the anterior portion of the canal versus 258.3 (219-300) degrees of decompression in the posterior portion of the canal, whereas the craniotomy generated an average of 229.3 (101-289) degrees of decompression in the anterior portion of the canal versus 250.3 (76-300) degrees of decompression in the posterior portion of the canal. There was no significant difference statistically. CONCLUSION The decision for an approach for optic canal decompression should be based on the site of the pathology and localization of canal involvement. Both techniques are equivalent in terms of proportion of nerve decompression.

Multicentric Giant Cell Glioblastoma: Case Report and Revision of the Literature

Glioblastoma multiforme is the most common primary brain tumor; however, the occurrence of this tumor in >1 site without continuity is rare, especially in association with unusual histologic variants. These features might have prognostic implications, especially in terms of surgical and adjuvant therapy. We present a case of a patient with 2 lesions, without continuity, initially thought to be metastatic disease, but that revealed to be glioblastoma multiforme, in its giant cell variant, an extremely rare subtype. We discuss the pathogenesis, diagnostic challenges, and appropriate treatment available in the literature.

Endoscopic Endonasal Drainage of Cerebral Abscess: A Case Report and Revision of the Literature

Brain abscess after rhinosinusitis is uncommon in clinical practice today, as a result of improvement in diagnosis as well as the increased use and efficacy of antibiotic treatment of rhinosinusitis. The role of expanded endoscopic endonasal approaches in treating skull base pathologies has significantly increased over the last decade, along with greater knowledge of the ventral anatomy of this region, offering a new method of brain abscess treatment. We present the case of a 24-year-old man with brain abscess secondary to acute sinusitis that was drained with an endoscopic endonasal approach. We discuss the pathogenesis, diagnosis, and appropriate treatment available in the literature.