Brain perfusion SPECT and MRI in foetal alcohol syndrome.

Six boys and five girls with a mean age of 8.6 (range 3 to 13) years with foetal alcohol syndrome (FAS) were studied by MRI and single photon emission computed tomography (SPECT) to find specific areas of vulnerability. Morphological anomalies shown in six of 11 patients by MRI were situated both cortically and subcortically: cortical atrophy (N = 2), dilated ventricle (N = 1), corpus callosum hypoplasia (N = 1), cerebellar atrophy (N = 2), one of the latter with Arnold-Chiari malformation (N = 1). Delayed myelination of the white matter was seen in two patients. Volumetric studies of the hippocampus showed morphological left-right asymmetry in five of eight patients. However, SPECT showed mild hypoperfusion of the left hemisphere in all 10 subjects. The negative left-right index was located especially in the left parietooccipital region, i.e. in the brain areas implicated in arithmetical and logical-grammatical functions, which are known to be affected in FAS. Normal left-right dominance was also lacking in the frontal area, i.e. the brain area affected in attention-deficit-hyperactivity disorder (ADHD). Detection of these abnormalities, although they are not unique to FAS, may be helpful in the diagnosis and any attempts at rehabilitation. Diverse morphological and functional abnormalities are more frequent than has usually been believed even in less impaired children with FAS.

Imaging of McCune-Albright syndrome using bone single photon emission computed tomography.

UNLABELLED: McCune-Albright syndrome is a rare disorder caused by a somatic, constitutively activating mutation in the gene (GNAS1) encoding the subunit of the signal transducing guanine nucleotide binding protein (G protein). The condition is characterized by polyostotic fibrous dysplasia, cafe-au-lait pigmentation and multiple endocrine hyperfunction, most commonly gonadotropin-independent precocious puberty in girls. Our patient, a 16-year-old male, with radiologically confirmed polyostotic fibrous dysplasia in cranium, thoracic and pelvic girdles, spine and extremities was studied using planar 99mTc-hydroxymethyldiphosphonate bone scintigraphy and single photon emission computed tomography. Using bone scintigraphy, an unusually extensive and asymmetric fibrous dysplasia was observed in the cranium, face, ribs, femur, humerus, ulna, tibia and the vertebral column, all on the left side. The whole body scan revealed only a few foci on the right side. Single photon emission computed tomography demonstrated extensive unilateral involvement in the base of the skull, facial bones, maxilla and mandible. All the lesions reached only the midline. These findings formed the basis of further treatment, eg. reconstructive surgery of facial asymmetry. CONCLUSION: McCune-Albright syndrome should be considered in the differential diagnosis when interpreting extensive unilateral predominance in paediatric bone scans.