Superficial Siderosis of the Central Nervous System (SS-CNS): A Mimic of Motor Neurone Disease
Esther Macken1, Noel Fanning2, Simon Cronin1
1Department of Neurology, National Neuroscience Centre, Cork University Hospital, Cork City, Ireland, 2Department of Radiology, National Neuroscience Centre, Cork University Hospital, Cork City, Ireland
Objective:

Superficial siderosis of the central nervous(SS-CNS) is a rare condition caused by haemosiderin deposition along the subpial surfaces of the brain and spinal cord secondary to chronic bleeding in the subarachnoid space. We present the case of a patient who was diagnosed with SS-CNS secondary to trauma from previous spinal surgery and which mimicked motor neurone disease.

Background:

MD is a 75-year-old right-handed male who presented to a neurology clinic in a large tertiary hospital with a ten-year history of imbalance. His speech had become slurred over the last five years and swallow initiation had deteriorated. He developed severe bilateral sensorineural hearing loss. His background was significant for lumbar spinal surgery in the UK in the 1980s.

An examination was demonstrative of diffuse limb fasciculations in the upper and lower extremities as well as the paravertebral muscles. He had an intention tremor in the upper limbs and walked with a broad based gait. He displayed a moderate cerebellar dysarthria and had hearing aids bilaterally. Power was intact in the upper and lower limbs with brisk reflexes.

Design/Methods:

NA

Results:
Magnetic resonance imaging(MRI) of his brain and whole spine demonstrated generalised cerebellar atrophy with susceptibility-weighted imaging(SWI) signal change suggesting blood enveloping the cerebellum, brainstem and spinal cord. A myelomeningocele was identified in the lumbar area. Neurophysiology showed no evidence of anterior horn cell disease. Extensive blood investigations and computed tomographic imaging of the thorax, abdomen, and pelvis were normal.
Conclusions:

Our patient was diagnosed with SS-CNS secondary to chronic bleeding from the site of previous spinal surgery. The source was felt to be at the site of the myelomeningocele for which he was referred to neurosurgery for consideration of surgical correction. SS-CNS can present similarly to motor neurone disease and although rare, should be considered in the differential as an MND-mimic.

10.1212/WNL.0000000000206104