Resection of an Intraventricular Metastatic Tumor with Minimally Invasive Port Technique: 2-Dimensional Operative Video.

The use of minimally invasive port technology has been proposed as a safe method to reduce retractor-induced parenchymal injury, particularly for the resection of deep-seated lesions.1-6 A 69-year-old woman with a history of previous colon cancer surgery presented with gait disturbances and progressive headaches. Magnetic resonance imaging revealed a tumor involving the right ventricular atrium that appeared consistent with metastasis. A parieto-occipital craniotomy was performed on the basis of the preoperatively planned surgical trajectory (Video 1). After the dural incision, the arachnoid was opened down to the sulcus under visualization with microscope. Next, the ViewSite Brain Access system tubular retractor (VBAS; Vycor Medical Inc., Boca Raton, Florida, USA) was introduced toward the lesion under navigation guidance. Once the ventricular atrium was entered, the surface of the tumor came into view. It was coagulated and progressively debulked with ultrasonic aspirator. After the mass was adequately decompressed, a plane of dissection between the ependyma and the tumor could be developed with dynamic angulation of the port in order to allow better visualization. Finally, the tumor could be gently rolled away from the choroid plexus and removed. Meticulous hemostasis was achieved, and the tubular retractor was slowly removed. The patient recovered uneventfully without neurologic deficits on follow-up, and the postoperative magnetic resonance imaging evidenced a complete resection of the tumor. The video illustrates technical nuances and demonstrates the feasibility of minimal access port surgery for the resection of intraventricular lesions with low morbidity and mortality using microsurgical techniques. The patient consented to the publication of her image.

Neurenteric Cyst of the Ventral Craniocervical Junction: Case Report and Review of the Literature.

BACKGROUND: Neurenteric cysts (NCs) are rare, non-neoplastic lesions arising from a failure of dissolution of the transient neurenteric canal between the foregut and the notochord. They are most frequently seen in the intradural extramedullary space in the lower cervical and upper thoracic spine. The authors describe a rare case of NC arising from the ventral cervicomedullary junction that was totally resected via a posterior approach. CASE DESCRIPTION: A 24-year-old woman presented with a 4-week history of neck pain and progressive left hemiparesis. Admission magnetic resonance imaging scans demonstrated an intradural extramedullary cystic mass lesion ventral to the upper spinal cord from medulla to C2. We performed a posterior approach and the lesion was totally removed. Surgical treatment resulted in resolution of the neurologic impairments. The histological results were consistent with NC. Postoperative course was uneventful. At the 6-month follow-up, the patient is asymptomatic and magnetic resonance imaging scan shows no residual lesion. CONCLUSIONS: NC is a rare lesion of the craniospinal junction and should be considered among differential diagnoses. Complete excision is the treatment of choice. In most instances a dorsal surgical approach will be satisfactory.

Schwannoma vestibular: abordaje y fresado del polo acústico / Vestibular schwanoma: surgical approaches & internal acoustic canal drilling

Objetivo: describir los abordajes al ángulo pontocerebeloso y los reparos anatómicos para el fresado del poro acústico. Descripción: el acceso a la región se puede llevar a cabo a través de un abordaje translaberíntico, retrosigmoideo o subtemporal. La decisión depende del examen clínico del paciente y sus estudios por imágenes. El fresado del poro acústico es utilizado para la remoción del componente intracanalicular del tumor y para la identificación y preservación del nervio facial. El bulbo yugular y el canalículo coclear por debajo, el seno petroso superior y la arteria subarcuata por arriba y los conductos semicirculares posterior, superior, la crus que los intersecta, el conducto endolinfático y el saco endolinfático hacia lateral son estructuras en estrecha relación anatómica con la región. El conocimiento de su localización es esencial para la preservación funcional del nervio facial y la audición. Conclusión: el conocimiento anatómico del área a fresar es elemental para alcanzar el resultado más cercano al standard contemporáneo de remoción total del tumor con preservación funcional del nervio facial y la audición, con la ayuda de una experimentada técnica microquirúrgica y monitoreo neurofisiológico intraoperatorio.

En-bloc craniotomy for the pre-sigmoid infra- and supratentorial approach: technical note.

INTRODUCTION: The combined supra-infratentorial approach as described some 30 years ago is to date considered a standard procedure for skull base procedures. Several variants have been devised, including preservation of the mastoid process. We herein present the cosmetically most sophisticated and fastest solution. OBJECTIVES: The authors describe an en bloc supra- and infratentorial pre-sigmoid combined approach. This variant of surgical technique involves a one-piece bone flap (temporal-suboccipital-mastoideal flap). We present another variant of craniotomy for the combined supra- and infratentorial pre-sigmoid approach that preserves the mastoid process and thus appears to be cosmetically much more acceptable. MATERIALS AND METHODS: Eight dry cadaveric skulls were used to develop an ideal one-piece excision of the cranial vault across the transverse sinus, including portions of the mastoid. Our aim was that no further drilling of the basal skull was needed. The procedure thereafter was practiced on a fresh prepared cadaveric specimen where its feasibility was again confirmed and was then applied to a patient suffering from a huge petroclival meningioma. It was very well tolerated and produced an excellent long-term cosmetic result. DISCUSSION: The combined supra- and infratentorial pre-sigmoid approach offers the possibility of resecting complex petroclival lesions. The variant presented herein is less time consuming than previously described methods and probably offers the best possible cosmetic result. CONCLUSION: The en-bloc cranioplastic approach with preservation of the mastoid process is a new, interesting variant of a classical technique that is easy to perform and has the intention of achieving the best possible cosmetic result.

Pseudoneoplasia calificante del neuroeje / Calcifying pseudo tumor of CNS

Objetive: to present a case of Calcifying Pseudoneoplasm of the Neuraxis (CPN). Description: a 17 years old woman, with menstrual disorders and a mild hyperprolactinemia. She suffered from a chronic and moderate headache with normal clinic and neurologic examination. Brain non contrast CT showed a hyperdense mass in the right frontal lobe with dural relationship. In MRI it was a non enhancing T1 weighted hyperintense lesion, and a T2 weighted hypointense mass. The sellar region was clean. Intervention: surgery with total excision was performed. The lesion was an off white an avascular tumor with meningeal adherence. It revealed a calcifiyed part and a soft mucoid portion. Histologically it presented amorphous, acellular chondromixoid matrix surrounded by pallisading spindle to polygonal epitheloid cells. These were tipically EMA positive and negative to GFAP. All these features led to the diagnosis of Calcifying Pseudoneoplasm of the Neuraxis. Conclusion: the CPN must be considered in the diagnosis and management of any patient with calcifyied, ossifyied mass of the Central Nervous System.

Abordaje cosmético supra/infratentorial pre-sigmoideo en bloque: técnica original / Cosmetic supra/infratentoral presigmoid approach: original technique

Objetivo: presentar una variante original del abordaje supra/infratentorial presigmoideo que preserva la apófisis mastoidea. Material y método: se practicó este abordaje en ocho cráneos secos, dos procedimientos por espécimen y posteriormente fue realizado en un preparado fresco. Posteriormente se realizó esta técnica quirúrgica en una paciente que presentaba una lesión compatible con un meningioma petroclivalen las imágenes de IRM. Discusión: el abordaje supra/ifratentorial pre-sigmoideo ofrece la posibilidad de resecar lesiones complejas de la región petroclival. Desde su popularización han sido diversas las variantes descriptivas sobre esta técnica quirúrgica con el objetivo de obtener un buen resultado cosmético postoperatorio. Conclusión: el abordaje supra/infratentorial pre-sigmoideo con preservación de la porción mastoidea en una sola pieza es una variante interesante del procedimiento clásico que tiene el propósito de lograr un buen resultado cosmético.

Laminoplastia cervical: relación entre descompresión anterior, evolución y diámetro del canal espinal / Cervical laminoplasty: relation between anterior decompression, evolution and diameter of the spinal canal

Objetivo: Determinar la relación entre el grado de descompresión anterior, la evolución clínica postoperatoria y el diámetro del canal espinal. Método: Realizamos un estudio prospectivo en 80 niveles operados (20 pacientes, 61.24 años promedio, 14 varones - 6 mujeres), con diagnóstico de mielopatia cervical por canal estrecho tratados con una laminoplastia expansiva. El compromiso neurológico fue evaluado con la Escala de Zeidman-Ducker, el diámetro del canal con el índice de Pavlov en radiología simple y la compresión anterior con los criterios de Nagata et al. en resonancia magnética. Las diferencias entre los porcentajes del grado clínico postoperatorio, el grado de descompresión anterior y el índice de Pavlov en los niveles operados, fueron evaluados con las pruebas de t de Student. Resultados: En los niveles operados (n:80), la mejoría el el compromiso neurológico (p=0.053) y en el grado de descompresión anterior (p=0.554) obtenidas en el postoperatorio, no tuvieron relación significativa con el indice de Pavlov. Conclusión: Luego de una laminoplastia el grado de descompresión anterior y la evolución clínica postoperatoria no tuvieron relación con el diámetro del canal.