J Neurol Surg A Cent Eur Neurosurg 2021; 82(03): 248-256
DOI: 10.1055/s-0040-1719107
Original Article

Endoscope-Assisted Neuroportal Transcerebellar Approach to the Fourth Ventricle: An Anatomical Study

Martina Piloni
1   Department of Neurosurgery and Gamma Knife Radiosurgery, Vita-Salute San Raffaele University and IRCCS San Raffaele Scientific Institute, Milan, Italy
Filippo Gagliardi
1   Department of Neurosurgery and Gamma Knife Radiosurgery, Vita-Salute San Raffaele University and IRCCS San Raffaele Scientific Institute, Milan, Italy
Michele Bailo
1   Department of Neurosurgery and Gamma Knife Radiosurgery, Vita-Salute San Raffaele University and IRCCS San Raffaele Scientific Institute, Milan, Italy
Lina R. Barzaghi
1   Department of Neurosurgery and Gamma Knife Radiosurgery, Vita-Salute San Raffaele University and IRCCS San Raffaele Scientific Institute, Milan, Italy
Anthony J. Caputy
2   Department of Neurological Surgery, The George Washington University, Washington, District of Columbia, United States
Pietro Mortini
1   Department of Neurosurgery and Gamma Knife Radiosurgery, Vita-Salute San Raffaele University and IRCCS San Raffaele Scientific Institute, Milan, Italy
› Author Affiliations


Background and Study Aims Minimally invasive approaches to deep-seated lesions still represent a fundamental issue in modern neurosurgery. Tubular retractors allow to enhance the operability of intraventricular lesions, minimizing the risk of damages to brain parenchyma. Increasing interest for portal devices has been mainly focused on supratentorial pathologies, while transportal approaches in the posterior cranial fossa have been rarely described. In the present study, the authors aimed to investigate the surgical exposure and operability obtained with a microsurgical neuroportal transcerebellar approach targeting the fourth ventricle, assisted by endoscopic exploration.

Material and Methods Six cadaveric specimens were provided for anatomical microsurgical dissection and Vycor ViewSite Brain Access System was used as tubular retractor. Surgical feasibility of the neuroportal transcerebellar approach was demonstrated through a definable and measurable parameter, the operability score.

Results The neuroport provided a surgical corridor away from eloquent structures to target the whole fourth ventricle cavity, preventing injury to cerebellar nuclei and white matter pathways and, potentially, minimizing the risk of surgical morbidity. Maximal operability was reached in the pontomedullary junction and medullary area of the ventricular floor. Transportal endoscopic assistance contributed to a further extension of surgical exposure in blind spots, corresponding to the ipsilateral lateral recess, the uppermost part of the fourth ventricle, and the obex.

Conclusion The neuroportal transcerebellar approach represents a viable alternative route to the fourth ventricle, avoiding vermian splitting or subarachnoid dissection of the cerebellomedullary cistern. Endoscopic assistance enhances the exposure of the surgical field and accomplishes a valid instrument for intraventricular orientation to ease microsurgical procedures.

Ethical Approval

All procedures performed in studies involving human participants were in accordance with the ethical standards of the institutional research committee and with 1964 Helsinki Declaration and its later amendments or comparable ethical standards.

Informed Consent

Informed consent was obtained from all individual participants included in the study.

Publication History

Received: 01 April 2020

Accepted: 08 June 2020

Article published online:
09 March 2021

© 2021. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

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