Black Holes in the Brain and Spine: A Dark Disease

ABSTRACT

A 7-year-old girl presented with difficulty in walking and bilateral vision impairment since past 15 days. On examination, she had disc pallor, flaccid paraparesis with positive Babinski sign, and reduced sensations below clavicle. She was diagnosed as anti-aquaporin-4 (AQP-4)-positive neuromyelitis optica. This article emphasizes the importance of recognizing its classical neuroimaging findings distinct from other disorders.

Case Study

A 7-year-old girl presented with a 15-day history of inability to walk, bilateral vision impairment, and failure to control urination. She had a history of optic neuritis at the age of 3 years, and long segment myelitis with optic neuritis at the age of 3.5 years. On both occasions, she was treated with intravenous methylprednisolone, and she recovered with residual left eye vision impairment. She was not on any chronic immunosuppression. On examination, she had a bilateral vision impairment, disc pallor, sluggishly reacting pupils, and flaccid paraparesis with a positive Babinski sign. She also had reduced pain and temperature sensation below clavicles and urinary retention. On the basis of her neuroimaging [Figures 1 and 2] and a strongly positive serum aquaporin-4 (AQP-4) antibody level, a diagnosis of anti-AQP-4-positive neuromyelitis optica was concluded.

Figure 1.

MRI of the brain in a child with anti-AQP-4-positive neuromyelitis optica. (A) T1 sagittal section showing multiple linear lesions perpendicular to the genu and body of the corpus callosum. (B) T1 axial sections showing multiple, well-defined, hypointense lesions (black holes) in the centrum semiovale. (C) Axial fluid attenuated inversion recovery sections showing non-multiple sclerosis-like widespread confluent, ill-defined lesions in the periventricular white matter

Figure 2.

T1 post-contrast fat-suppressed coronal image (A) showing thickening and enhancement of the optic chiasma (white arrow), the intraorbital segments of the optic nerves were also involved. T1 post-contrast sagittal image of the spine (B) showing longitudinally extensive involvement of the cervico-dorsal cord extending up to the floor of the fourth ventricle. Axial T1 section of the cord (C) showing paired black holes (white arrowhead), which appeared like “owls eyes” on T2-weighted images

Large necrotic lesions in cerebral white matter appearing as T1 black holes are a well-described feature of anti-AQP-4-positive neuromyelitis optica. The callosal lesions in the index child have a characteristic “marbled” appearance, as described in anti-AQP-4-positive neuromyelitis optica. These lesions are distinctive from calloso-septal lesions (Dawson fingers) seen in multiple sclerosis.[1,2] There was also distinctive contiguous involvement of posterior optic nerve and optic chiasma, a feature typical of anti-AQP-4-positive neuromyelitis optica. Interestingly, the spinal magnetic resonance imaging (MRI) in this child gave the “owl’s eye appearance,” a feature that is typically described with anterior horn cell myelitis. Recognition of these changes in neuromyelitis optica spectrum disorder and identifying them as distinct from other disorders involving the eye, brain, or spinal cord are necessary to choose the right strategy of immunomodulation.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.