Diffusion MRI of the facial-vestibulocochlear nerve complex: a prospective clinical validation study

TY - JOUR

T1 - Diffusion MRI of the facial-vestibulocochlear nerve complex

T2 - a prospective clinical validation study

AU - Shapey, Jonathan

AU - Vos, Sjoerd B.

AU - Mancini, Laura

AU - Sanders, Brett

AU - Thornton, John S.

AU - Tournier, Jacques Donald

AU - Saeed, Shakeel R.

AU - Kitchen, Neil

AU - Khalil, Sherif

AU - Grover, Patrick

AU - Bradford, Robert

AU - Dorent, Reuben

AU - Sparks, Rachel

AU - Vercauteren, Tom

AU - Yousry, Tarek

AU - Bisdas, Sotirios

AU - Ourselin, Sebastien

N1 - Funding Information: This research was funded in whole, or in part, by the Wellcome Trust [203145Z/16/Z; 203148/Z/16/Z; WT106882], EPSRC [NS/A000050/1; NS/A000049/1], National Brain Appeal [NBA/T&I/N-ONC], and MRC Confidence in Concept (CiC) [M C_PC_17180]. TV is supported by a Medtronic/Royal Academy of Engineering Research Chair [RCSRF1819/7/34]. Publisher Copyright: © 2023, The Author(s).

PY - 2023/11

Y1 - 2023/11

N2 - Objectives: Surgical planning of vestibular schwannoma surgery would benefit greatly from a robust method of delineating the facial-vestibulocochlear nerve complex with respect to the tumour. This study aimed to optimise a multi-shell readout-segmented diffusion-weighted imaging (rs-DWI) protocol and develop a novel post-processing pipeline to delineate the facial-vestibulocochlear complex within the skull base region, evaluating its accuracy intraoperatively using neuronavigation and tracked electrophysiological recordings. Methods: In a prospective study of five healthy volunteers and five patients who underwent vestibular schwannoma surgery, rs-DWI was performed and colour tissue maps (CTM) and probabilistic tractography of the cranial nerves were generated. In patients, the average symmetric surface distance (ASSD) and 95% Hausdorff distance (HD-95) were calculated with reference to the neuroradiologist-approved facial nerve segmentation. The accuracy of patient results was assessed intraoperatively using neuronavigation and tracked electrophysiological recordings. Results: Using CTM alone, the facial-vestibulocochlear complex of healthy volunteer subjects was visualised on 9/10 sides. CTM were generated in all 5 patients with vestibular schwannoma enabling the facial nerve to be accurately identified preoperatively. The mean ASSD between the annotators’ two segmentations was 1.11 mm (SD 0.40) and the mean HD-95 was 4.62 mm (SD 1.78). The median distance from the nerve segmentation to a positive stimulation point was 1.21 mm (IQR 0.81–3.27 mm) and 2.03 mm (IQR 0.99–3.84 mm) for the two annotators, respectively. Conclusions: rs-DWI may be used to acquire dMRI data of the cranial nerves within the posterior fossa. Clinical relevance statement: Readout-segmented diffusion-weighted imaging and colour tissue mapping provide 1–2 mm spatially accurate imaging of the facial-vestibulocochlear nerve complex, enabling accurate preoperative localisation of the facial nerve. This study evaluated the technique in 5 healthy volunteers and 5 patients with vestibular schwannoma. Key Points: • Readout-segmented diffusion-weighted imaging (rs-DWI) with colour tissue mapping (CTM) visualised the facial-vestibulocochlear nerve complex on 9/10 sides in 5 healthy volunteer subjects. • Using rs-DWI and CTM, the facial nerve was visualised in all 5 patients with vestibular schwannoma and within 1.21–2.03 mm of the nerve’s true intraoperative location. • Reproducible results were obtained on different scanners.

AB - Objectives: Surgical planning of vestibular schwannoma surgery would benefit greatly from a robust method of delineating the facial-vestibulocochlear nerve complex with respect to the tumour. This study aimed to optimise a multi-shell readout-segmented diffusion-weighted imaging (rs-DWI) protocol and develop a novel post-processing pipeline to delineate the facial-vestibulocochlear complex within the skull base region, evaluating its accuracy intraoperatively using neuronavigation and tracked electrophysiological recordings. Methods: In a prospective study of five healthy volunteers and five patients who underwent vestibular schwannoma surgery, rs-DWI was performed and colour tissue maps (CTM) and probabilistic tractography of the cranial nerves were generated. In patients, the average symmetric surface distance (ASSD) and 95% Hausdorff distance (HD-95) were calculated with reference to the neuroradiologist-approved facial nerve segmentation. The accuracy of patient results was assessed intraoperatively using neuronavigation and tracked electrophysiological recordings. Results: Using CTM alone, the facial-vestibulocochlear complex of healthy volunteer subjects was visualised on 9/10 sides. CTM were generated in all 5 patients with vestibular schwannoma enabling the facial nerve to be accurately identified preoperatively. The mean ASSD between the annotators’ two segmentations was 1.11 mm (SD 0.40) and the mean HD-95 was 4.62 mm (SD 1.78). The median distance from the nerve segmentation to a positive stimulation point was 1.21 mm (IQR 0.81–3.27 mm) and 2.03 mm (IQR 0.99–3.84 mm) for the two annotators, respectively. Conclusions: rs-DWI may be used to acquire dMRI data of the cranial nerves within the posterior fossa. Clinical relevance statement: Readout-segmented diffusion-weighted imaging and colour tissue mapping provide 1–2 mm spatially accurate imaging of the facial-vestibulocochlear nerve complex, enabling accurate preoperative localisation of the facial nerve. This study evaluated the technique in 5 healthy volunteers and 5 patients with vestibular schwannoma. Key Points: • Readout-segmented diffusion-weighted imaging (rs-DWI) with colour tissue mapping (CTM) visualised the facial-vestibulocochlear nerve complex on 9/10 sides in 5 healthy volunteer subjects. • Using rs-DWI and CTM, the facial nerve was visualised in all 5 patients with vestibular schwannoma and within 1.21–2.03 mm of the nerve’s true intraoperative location. • Reproducible results were obtained on different scanners.

KW - Cranial nerves

KW - Diffusion magnetic resonance imaging

KW - Magnetic resonance imaging

KW - Vestibular schwannoma

UR - http://www.scopus.com/inward/record.url?scp=85162064397&partnerID=8YFLogxK

U2 - 10.1007/s00330-023-09736-4

DO - 10.1007/s00330-023-09736-4

M3 - Article

AN - SCOPUS:85162064397

SN - 0938-7994

VL - 33

SP - 8067

EP - 8076

JO - European Radiology

JF - European Radiology

IS - 11

ER -