Subluxación atlantoaxial en artritis reumatoidea. Resolución por odontoidectomía endonasal endoscópica y fusión e instrumentación por abordaje posterior. Reporte de caso

La subluxación atlantoaxial es la lesión más frecuente en la columna cervical causada por la artritis reumatoidea. Se manifiesta por rigidez de nuca, dolor cervical y déficit neurológico. El diagnóstico se realiza con tomografía computarizada e imágenes de resonancia magnética. El intervalo atlanto dental anterior mayor a 5mm indica inestabilidad atlantoaxial, el intervalo atlanto dental posterior menor a 14mm advierte riesgo neurológico. Las indicaciones más frecuentes de cirugía son: dolor cervical severo, inestabilidad y síntomas de mielopatía. Cuando existe compresión medular es necesaria la descompresión cervical alta sea por vía posterior o por vía anterior (odontoidectomía endonasal versus transoral). La línea rinopalatina nos indicará la factibilidad de una odontoidectomía endonasal endoscópica (OEE). El objetivo de la presentación del presente caso es compartir nuestra experiencia con la primera odontoidectomía endonasal endoscópica realizada en nuestro país y fomentar la utilización de la técnica. La cirugía fue realizada en un paciente con cuadriparesia espástica por subluxación atlantoaxial por artritis reumatoidea y que presentó excelente evolución pos operatoria, con recuperación casi completa. La OEE es una técnica operatoria mínimamente invasiva, ideal para pacientes con múltiples comorbilidades y que ofrece de buenos a excelentes resultados.

Atlantoaxial subluxation is the most common injury to the cervical spine caused by rheumatoid arthritis. It is manifested by neck stiffness, neck pain and neurological deficit. Diagnosis is made with computed tomography and magnetic resonance imaging. The anterior dental atlanto interval greater than 5mm indicates atlantoaxial instability, the posterior dental atlanto interval less than 14mm warns of neurological risk. The most frequent indications for surgery are: severe neck pain, instability and symptoms of myelopathy. When there is spinal cord compression, upper cervical decompression is necessary, either via a posterior or anterior approach (endonasal versus transoral odontoidectomy). The rhinopalatine line will indicate the feasibility of an endoscopic endonasal odontoidectomy (EEO). The objective of the presentation of this case is to share our experience with the first endoscopic endonasal odontoidectomy performed in our country and to promote the use of the technique. The surgery was performed on a patient with spastic quadriparesis due to atlantoaxial subluxation due to rheumatoid arthritis and who presented excellent postoperative evolution, with almost complete recovery. EEO is a minimally invasive surgical technique, ideal for patients with multiple comorbidities and offering good to excellent results.

Extended Endoscopic Endonasal Clipping of Intracranial Aneurysms: An Anatomic Feasibility Study.

BACKGROUND: Intracranial aneurysms (IAs) located in the midline region represent formidable challenge owing to their deep location. The objective of this study was to assess feasibility and identify the limitations of endoscopic endonasal clipping of IAs. We further aimed to describe the locations and characteristics of aneurysms that may be amenable for endoscopic endonasal clipping; thus outlining the indications of these approaches. METHODS: Fifteen latex-injected cadaveric heads were used for endoscopic endonasal exposure of anterior and posterior cerebral circulations. An aneurysm simulator model with 2 different sizes was used at the common sites for IAs to emulate a real surgery. Key measured parameters included "exposure of vessels and their respective perforators," "ability to gain proximal/distal control," and "possibility of clip placement" according to the size, direction, and location of the aneurysm model. Maneuverability of instruments and the need for pituitary gland transposition were assessed and recorded as well. RESULTS: Exposure of the anterior communicating artery complex and the common sites of posterior circulation aneurysms were feasible. The size, location, and direction of the aneurysm model had an impact on obtaining proximal and/or distal control, and the ability of clip placement. CONCLUSIONS: Clipping of midline aneurysms of the posterior circulation is feasible via endoscopic endonasal approach. Small-sized ventrally and medially directed aneurysm models carried a better probability of getting proximal and/or distal control, as well as better overall ability to place a clip. The endonasal route seems to provide a limited condition for proper management of anterior circulation aneurysms.

Endonasal anatomy of the olfactory neural network: Surgical implications.

OBJECTIVES/HYPOTHESIS: Define the anatomic distribution of the olfactory filaments within specific mucosal regions of the nasal cavity. STUDY DESIGN: Cadaveric study. METHODS: Seventeen cadaveric specimens (34 sides) were dissected to study the anatomical distribution and density of olfactory fila within different regions of the nasal cavity. Olfactory fila were dissected retrogradely to their point of entry into the anterior cranial fossa through the cribriform plate. Anatomic relationships among various components of the olfactory system and their corresponding arterial supply were determined subjectively. RESULTS: The highest density of olfactory fila was found at the mucosa of the ethmoid roof and superior turbinates. Olfactory fila were found at regions not previously considered to be part of the olfactory system: lateral wall of the nose, ethmoidal bullae, and between the os sphenoidale and arc of the posterior choana. Furthermore, at the septum, 20% of the olfactory fila crossed contralaterally before exiting the nose. The anterior ethmoidal arteries were the primary blood supply to the olfactory epithelium. CONCLUSIONS: This study suggests that olfactory filaments extend beyond previously established boundaries. These findings may have clinical implications regarding oncologic resections and could serve as the foundation for the development of techniques that better preserve olfactory function. LEVEL OF EVIDENCE: NA Laryngoscope, 2473-2477, 2018.