case_images: PMC7149416_01
case_images: .Brain MRI of case 1. (a) The lesion (arrows) is enhanced on T1-weighted image and extends into the superior orbital fissure. (b) The high-intensity ring appearance (arrowheads) around the left optic nerve is seen on short tau inversion recovery (STIR) MRI. (c) The high-intensity ring appearance has disappeared on day 21 after initiating treatment.
case_images: CRINM2020-6737018.002.jpg
case_images: PMC7149416_01_CRINM2020-6737018.002.jpg
case_images: fig2
case_images: The lesion was enhanced on the T1-weighted image and was observed to have extended into the superior orbital fissure (Figure 2(a)). Moreover, a high-intensity ring appearance around the left optic nerve was observed on short tau inversion recovery (STIR) MRI (Figure 2(b)). His follow-up brain MRI three weeks after starting treatment revealed a reduction of the asymmetrical high-intensity ring appearance around the optic nerve (Figure 2(c)).
case_images: PMC7149416_02
case_images: Brain MRI of cases 2-4. In case 2 (a), the high-intensity ring appearance (arrowheads) around the left optic nerve is found on STIR MRI. In cases 3 (b) and 4 (c), the high-intensity ring appearance (arrowheads) around the right optic nerve is found on fat-suppressed T2-weighted MRI.
case_images: CRINM2020-6737018.003.jpg
case_images: PMC7149416_04_CRINM2020-6737018.003.jpg
case_images: fig3
case_images: While no mass lesion in the cavernous sinus was detected by brain MRI, a high-intensity ring appearance around the right optic nerve was observed in fat-suppressed T2-weighted MRI (Figure 3(c)).
case_images: PMC7149416_03
case_images: Brain MRI of cases 2-4. In case 2 (a), the high-intensity ring appearance (arrowheads) around the left optic nerve is found on STIR MRI. In cases 3 (b) and 4 (c), the high-intensity ring appearance (arrowheads) around the right optic nerve is found on fat-suppressed T2-weighted MRI.
case_images: CRINM2020-6737018.003.jpg
case_images: PMC7149416_04_CRINM2020-6737018.003.jpg
case_images: fig3
case_images: While no mass lesion in the cavernous sinus was detected by brain MRI, a high-intensity ring appearance around the right optic nerve was observed in fat-suppressed T2-weighted MRI (Figure 3(c)).
case_images: PMC7149416_04
case_images: Brain MRI of cases 2-4. In case 2 (a), the high-intensity ring appearance (arrowheads) around the left optic nerve is found on STIR MRI. In cases 3 (b) and 4 (c), the high-intensity ring appearance (arrowheads) around the right optic nerve is found on fat-suppressed T2-weighted MRI.
case_images: CRINM2020-6737018.003.jpg
case_images: PMC7149416_04_CRINM2020-6737018.003.jpg
case_images: fig3
case_images: While no mass lesion in the cavernous sinus was detected by brain MRI, a high-intensity ring appearance around the right optic nerve was observed in fat-suppressed T2-weighted MRI (Figure 3(c)).