High-resolution MR imaging of cranial neuropathy in patients with anti-GQ1b antibody syndrome

Objective: The value of conventional MRI in patients anti-GQ1b antibody syndrome is subject to debate. Our purpose was to evaluate the diagnostic accuracy of high-resolution MRI for detecting cranial nerve abnormalities in patients with anti-GQ1b antibody syndrome.

Materials and methods: This retrospective cohort study enrolled 15 anti-GQ1b-positive patients diagnosed with MFS and related disorders and 17 age-matched controls, all of whom underwent high-resolution MR imaging including pre-contrast and contrast-enhanced (CE) 3D FLAIR and 3D CE T1-weighted turbo field echo (T1-TFE) between 2010 and 2016. The diagnostic performance of high-resolution MRI was assessed using the area under the curve (AUC) of the receiver operating characteristics curve. Inter- and intraobserver agreements were calculated using kappa statistics and intraclass correlation coefficients (ICC), respectively.

Results: Ophthalmoplegia, ataxia, and hypo/areflexia were present in 100%, 60%, and 67%, respectively. Other neurologic findings included ptosis (40%), mydriasis (13%), and facial (27%) and bulbar (13%) palsy. Fourteen of sixteen (88%) MR examinations in 15 patients demonstrated at least one cranial nerve abnormality corresponding to the clinical findings. The involved cranial nerves on MRI were the IIIrd cranial nerve in 14 patients, VIth in nine, VIIth in four, Vth in one, and VIIIth in one. AUC values for detecting cranial neuropathy on high-resolution MRI were 0.938 (95% CI: 0.795-0.992) on a per patient basis. Inter- and intraobserver agreements were 0.842 and 0.945, respectively.

Conclusion: High-resolution 3D FLAIR and CE 3D T1-TFE MRI has high reliability and accuracy for demonstrating cranial neuropathy in patients with anti-GQ1b antibody syndrome.