Superficial siderosis of the CNS: MR diagnosis and clinical findings.
OBJECTIVE
To report the clinical and neuroradiologic findings of superficial siderosis of the CNS, due to chronic subarachnoid bleeding of unknown origin.


METHODS
We observed seven cases. The main clinical manifestations were progressive deafness and ataxia. Four patients had had previous cranial or cervical trauma, with root avulsion in two, many years before onset of deafness and ataxia. Neuroradiologic studies included MR (0.5 T in four and 1.5 T in three) and angiography of the brain in all cases, CT in six cases, MR of the spine in six, and myelography in four.


RESULTS
MR demonstrated a rim of marked hypointensity in T2-weighted images, consistent with hemosiderin deposits, on the surface of cerebellum, brain stem, inferior part of cerebral hemispheres, and spinal cord. CT showed cerebellar atrophy in five cases, and a rim of mild hyperdensity around the brain stem in two. Angiographic studies were negative. Myelography showed cervical nerve root avulsion in two cases and a cervicodorsal extradural cyst in one. Cerebrospinal fluid contained RBCs in all the six examined cases.


CONCLUSIONS
Although CT may occasionally suggest the diagnosis of superficial siderosis, MR demonstrates this abnormality to better advantage.
Bracchi
M
M
Department of Neuroradiology, University of Torino, Italy.
Savoiardo
M
M
Triulzi
F
F
Daniele
D
D
Grisoli
M
M
Bradac
G B
GB
Agostinis
C
C
Pelucchetti
D
D
Scotti
G
G
D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging; D002490:Central Nervous System / Q000473:pathology; D002493:Central Nervous System Diseases / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D012806:Siderosis / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000209:etiology; D014057:Tomography, X-Ray Computed