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

Abstract

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.

Intraoperative use of low-field magnetic resonance imaging for brain tumors: A systematic review

“…Our systematic review process screened 525 articles and, after evaluating the titles, abstracts, and full text, 21 of them were selected for inclusion in the final analysis. [3,6,7,[12][13][14]16,18,[21][22][23][25][26][27][28]32,33,35,36,38,39] e articles were screened and quality assessed independently by JM and AB, and any discrepancies were resolved by AA. e screening process and quality assessment procedure are thoroughly delineated in Figure 1 of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flowchart, and Tables 1a and b, respectively.…”

“…However, it is important to note that this came at the expense of a longer surgical duration. Wu et al 2009 [36] ✩✩✩✩ ✩✩ ✩✩ Kim et al 2013 [13] ✩✩✩ ✩✩ ✩✩ Makary et al 2011 [18] ✩✩✩✩ ✩ ✩ White et al 2018 [35] ✩✩✩✩ ✩ ✩ García et al 2017 [8] ✩✩✩ ✩✩ ✩✩ Bohinski et al 2001 [3] ✩✩✩ ✩ ✩✩ Nimsky et al 2003 [21] ✩✩✩✩ ✩✩ ✩ Kırış and Arıca 2011 [14] ✩✩✩ ✩ ✩✩✩ Hlavica et al 2013 [12] ✩✩✩ ✩✩ ✩✩✩ iabpha and Hansasuta 2016 [32] ✩✩✩ ✩ ✩ Livne et al 2014 [16] ✩✩✩✩ ✩✩ ✩✩ Senft et al 2010 [26] ✩✩✩ ✩✩ ✩✩ Nimsky et al 2003 [22] ✩✩✩ ✩ ✩✩✩ Senft et al 2008 [27] ✩✩✩ ✩✩ ✩✩✩ Zimmermann et al 2001 [39] ✩✩✩ ✩ ✩✩ Zimmermann et al 2000 [38] ✩✩✩ ✩ ✩✩ Czyż et al 2011 [7] ✩✩✩ ✩✩ ✩✩ Buchfelder et al 2002 [6] ✩✩✩ ✩✩ ✩✩✩ Senft et al 2010 [28] ✩✩✩ ✩✩ ✩✩ Ungar et al 2021 [33] ✩✩✩ ✩✩ ✩✩ ✩: 1 point, ✩✩: 2 points, ✩✩✩: 3 points, ✩✩✩✩: 4 points Our review revealed that the use of low-field IMRI has been associated with a significant increase in the number of patients who achieved GTR of brain tumors. Attaining GTR is of paramount importance, as it has been shown to be associated with prolonged survival in various brain tumor types.…”

“…Senft et al 2010 [26] Prospective cohort 204 59 115/89 Polestar N20 0.15-T Senft et al 2011 [25] Randomized controlled trial 24 55 16/8 Polestar N20 0.15-T Nimsky et al 2003 [22] Case-control 20 29 10/10 *MO-MR scanner 0.2-T Senft et al 2008 [27] Retrospective cohort 103 48 NR Polestar N20 0.15-T Zimmermann et al 2001 [39] Retrospective cohort 32 47 15/17 S-MR-SSSP* 0.5-T Zimmermann et al 2000 [38] Retrospective cohort 44 44 24/20 S-MR-SSSP* 0.5-T Czyż et al 2011 [7] Prospective cohort 58 54 24/34 Polestar N20 0.15-T Buchfelder et al 2002 [6] Prospective cohort 29 33 18/11 *MO-MR Scanner 0.2-T Senft et al 2010 [28] Prospective observational 63 46 36/27 Polestar N20 0.15-T Ungar et al 2021 [33] Retrospective cohort [36] 0.15T Gd-DPTA NNG T1 7 1.8 Kim et al 2013 [13] 0.15T Gd-DPTA (4 mL/kg) NNG T1-axial and coronal 7 NR Makary et al 2011 [18] 0.15T Gd-DPT NR *T1-axial or T2/ FLAIR 13 0.5-2…”

“…Buchfelder et al 2002 [6] 0.2T NR NNG T1 15 NR Senft et al 2008 [27] 0.15T Gd-DPT NNG T1, T2 and FLAIR NR NR Ungar et al 2021 [33] 0.15T Gd-DPT MSEP T1, T2 and FLAIR 49 NR Gd-DPT: Gadolinium-diethylenetriamine penta-acetic acid, NR: Not reported, NS: Not specified, *T1-axial with gadolinium for enhancing non-pituitary tumors or T2/FLAIR for nonenhancing non-pituitary tumors. NNG: Neuronavigation, MSEP: Motor or sensory-evoked potentials, OR: Operating room, hr/s: Hour/s, MRI: Magnetic resonance imaging, FLAIR: Fluid-attenuated inversion recovery, LF-IMRI: Low-field intraoperative magnetic resonance imaging, FLASH: Fast low angle shot [13] 0.15T Pituitary adenomas 182 154 30 2 17.5-83.3 Makary et al 2011 [18] 0.15T Oligodendroglioma, anaplastic astrocytoma, caraniopharyngioma NR NR 28 NR 43…”

Daily television exposure, parent conversation during shared television viewing and socioeconomic status: Associations with curiosity at kindergarten

“…Why do you think that happened?”), our results suggest the possibility that more frequent conversation (in all contexts, not just television viewing) can promote imaginative expression (one of the underpinnings of curiosity [ 56 ]) at kindergarten. Interventions to promote dialogic exchanges and language-rich caregiver-child interactions have been shown to be beneficial for early imagination and learning, and may be similarly promotive for early childhood curiosity [ 57 , 58 ].…”