Neuroimaging in nine patients with inversion duplication of the short arm of chromosome 8.
Inversion duplication 8p is a rare chromosome disorder characterised by severe mental retardation, minor facial dysmorphisms, and corpus callosum agenesis. Few cerebral imaging studies have been reported. We describe 9 patients with an inversion duplication 8p, involving variable segments of the short arm of chromosome 8. MRI was performed in 8 patients and 2 patients underwent CT scanning. The images were systematically reviewed. All patients suffered from severe mental retardation. Head circumference was between 0 and + 2 SD in 7 patients. The corpus callosum was absent in 6, and thin (but complete) in 3 patients. Hypoplasia of the (inferior) cerebellar vermis was observed in 6 patients. Enlargement of the ventricular system and associated hippocampal maldevelopment were found in all patients. The supratentorial external CSF spaces were enlarged in 6 patients, and in 3 patients there was a remarkable enlargement of the retrocerebellar arachnoidal space. Cerebral white matter showed mildly delayed myelination in 7 patients, and periventricular lesions of variable extent in 6 patients. The pattern of imaging abnormalities was non-specific, but remarkably similar between patients. We found no correlation between the severity of the clinical features, imaging results, and extent of the chromosomal aberration.
Feenstra
I
I
Department of Human Genetics, Radboud University Nijmegen Medical Centre, 6500 HB Nijmegen, The Netherlands. i.feenstra@antrg.umcn.nl
van Ravenswaaij
C M A
CM
van der Knaap
M S
MS
Willemsen
M A A P
MA
D000293:Adolescent; D001921:Brain / Q000000981:diagnostic imaging* / Q000473:pathology*; D001927:Brain Diseases / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D007446:Chromosome Inversion; D002898:Chromosomes, Human, Pair 8 / Q000235:genetics*; D005260:Female; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000000981:diagnostic imaging / Q000235:genetics / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D014057:Tomography, X-Ray Computed