Vol 55, No 2 (2021)
Research Paper
Published online: 2021-02-09

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Utility of the Polestar N30 low-field MRI system for resecting non-enhancing intra-axial brain lesions

Lior Ungar1, Zion Zibly1, Anton Wohl1, Ran Harel1, Moshe Hadani1, Moshe Attia1, Roberto Spiegelmann1, Zeev Feldman1, Jacob Zaubermann1, Nachshon Knoller1, Zvi R. Cohen1
Pubmed: 33559873
Neurol Neurochir Pol 2021;55(2):202-211.


Background. To determine the utility of an intraoperative magnetic resonance imaging (iMRI) system, the Polestar N30, for enhancing the resection control of non-enhancing intra-axial brain lesions.

Materials and methods. Seventy-three patients (60 males [83.3%], mean age 37 years) with intra-axial brain lesions underwent resection at Sheba Medical Centre using the Polestar between February 2012 and the end of August 2018. Demographic and imaging data were retrospectively analysed. Thirty-five patients had a non-enhancing lesion (48%).

Results. Complete resection was planned for 60/73 cases after preoperative imaging. Complete resection was achieved in 59/60 (98.3%) cases. After iMRI, additional resection was performed in 24/73 (32.8%) cases, and complete resection was performed in 17/60 (28.8%) cases in which a complete resection was intended. In 6/13 (46%) patients for whom incomplete resection was intended, further resection was performed. The extent of resection was extended mainly for non-enhancing lesions: 16/35 (46%) as opposed to only 8/38 (21%) for enhancing lesions. Further resection was not significantly associated with sex, age, intended resection, recurrence, or affected side. Univariate analysis revealed non-eloquent area, intended complete resection, and enhancing lesions to be predictive factors for complete resection, and non-enhancing lesions and scan time to be predictive factors for an extended resection. Non-enhancement was the only independent factor for extended resection.

Conclusions. The Polestar N30 is useful for evaluating residual non-enhancing intra-axial brain lesions and achieving maximal resection.

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