Abnormalities of the basal ganglia and thalami

1. Abnormalities of the basal ganglia and thalami S.Alj, M.OualiIdrissi, N. Cherif El Idrissi El Ganouni, O.Essadki, A.OusehalRadiology department, IbnTofail Hospital , CadiAyyad University, Marrakech. NR4

2. Introduction • Several diseases may cause MR signal abnormalities of the basal ganglia and thalami. • Signal abnormalities are usually non specific. • Analysis of the clinical manifestations , type of signal, location of the lesions and associated abnormalities can help to achieve the correct diagnosis.

3. Methods and patients • The study included : patients with signal abormalities of basal ganglia and thalami in MRI. • MRI technique: -MRI 1,5 Tesla. -with T1, T2 , T2* ,Flair and diffusion sequences .

4. Results 1-Epidemiological features: • Thirteen patients were included in the study . • There was seven women and 6 men. • Patients were aged between 8 and 70 years (mean age= 27,15).

5. Results 2-Clinical manifestations:

6. Results 3-Imaging features: 3.1-Location of the signal abnormalities 3.2-Associated abnormalities: • White matter abnormalities were found in 4 patients

7. Results 3.3-etiology:

8. Figure 1: Fahr’s disease Calcifications of the basal ganglia and thalami on CT Bilateral and symetric hyperintensity of the basal ganglia and thalami on T1 WI

9. Fahr’s disease Comment • Rare clinicalentity • characterized by bilateral calcifications of the basal ganglia, thalami, dentate nuclei of the cerebellum, and the white matter of the cerebral hemisphere • Clinical manifestations: characterized by movement disorders, dementia and behavioral disorders • Computed tomography: calcifications are visible as high-density areas. • Magnetic resonance image: the calcifications have different signal intensities. It’s probably related to the stage of the disease, and the volume of the calcium deposit.

10. Figure 2:Wilson disease. T2-weighted MR image depicts bilaterally symmetric areas of abnormal T2 hypersignal in the thalamus, putamina and caudate nuclei.

11. Wilson disease Comment • caused by the accumulation of copper resulting from a deficiency of ceruloplasmin. • Clinical manifestations : dysarthria, tremors, ataxia, Parkinsonian symptoms, and psychiatric problems. The Kayser-Fleisher rings in the cornea is characteristic when found. • MRI : - areas of T2 hyperintensity in the putamen (a common finding), -Other locations of the signal abnormalities : globus pallidus, caudate nuclei, and thalamus (ventrolateral aspect ). -The cortical and subcortical regions, mesencephalon, pons, vermis, and dentate nuclei may also be involved.

12. Figure 3: Creutzfeldt Jacob disease 30 years aged patient with rapidely progressive demantia. Bilateral hyperintensities on FLAIR WI of cerebral cortex and basal ganglia .

13. Creutzfeldt jacob disease(CJD) Comment • fatal neurodegenerative disorder caused by prions • Four main subtypes: sporadic, familial, iatrogenic, and variant CJD • Clinical manifestations: rapidly progressive dementia, myoclonus. • Electroencephalography : Characteristic periodic sharp-wave complexes. • MRI of sporadic CJD: • diffusion-weighted MR imaging: increasingly important for the diagnosis • Bilateral restricted diffusion of cerebral cortex and basal ganglia .

14. Figure 4:Hypoglycemia 70 years aged patient type 2 diabetic . Bilateral FLAIR hypersignal in the temporal and occipital cerebral cortex, and basal ganglia.

15. Hypoglycemia Comment • Brain damage is dependent on the severity and duration of hypoglycaemia • Clinical manifestation s:patients with severe hypoglycemia have coma and are typically diabetic receiving treatment with oral hypoglycemic agents • MRI: -bilateral T2 prolongation in the cerebral cortex, hippocampi, and basal ganglia. -transient white matter abnormalities DW MR findings, involving the splenium of the corpus callosum, internal capsules and corona radiata have been reported in milder hypoglycemia

16. Figure 4:Neuro-Behçet Disease 40 years aged patient with Behcet disease . Hyperintense lesions of the left midbrain, cerebellar hemispheres and the basal ganglia.

17. Neuro-Behçet Disease • multisystemic, recurrent inflammatory disorder of unknown cause • Clinical manifestations: triad of uveitis, oral ulcers, and genital with neurological ulcers manifestations (headache, dysarthria, cerebellar signs, sensory signs) • MRI: -lesions hyperintense on T2-WI , hypointense on T1-WI, enhance after contrast material administration -Involving the brainstem, basal ganglia (bilateral involvement in one-third of cases), and thalamus . -Less commonly, the white matter of the cerebral hemispheres and cervicothoracic spinal cord are involved.

18. Other Comment • Other inflammatory and demyelinating disease may present with basal ganglia and thalami lesions (Multiple sclerosis , systemic lupus with neurological manifestations..) • Clinical manifestations: variety of neurological deficits • MRI: (MS) -Gray matter T2-hypointensity, -suggestive of excessive iron deposition -associated with worsening disability in patients with MS

19. Conclusion • Signal abnormalities of basal ganglia are usually non specific. • Clinical manifestations and the location of this signal abnormalities led to diagnosis. • The etiologies vary widely corresponding generally to uncommon diseases (such Fahr’s disease), or to a rare manifestation of some commun pathologies (such multiple sclerosis).

20. References 1-CC Tchoyoson Lim. Magnetic Resonance Imaging Findings in Bilateral Basal Ganglia Lesions. Ann Acad Med Singapore 2009;38:795-802. 2-AN. Hegde, S Mohan,N Lath, CC. Tchoyoson Lim. Differential diagnosis for bilateral abnormalities of the basal ganglia and thalamus. RadioGraphics 2011; 31:5–30. 3-GA Cavalcanti-Mendes, GTC De Carvalho, PP Christo, LF. Malloy-Diniz, A A De Sousa.An unusual case of fahr’s disease.Arq Neuropsiquiatr 2009;67(2-B):516-518. 4-M Neema and al. Deep gray matter involvement on brain mri scans is associated with clinical progression in multiple sclerosis. J Neuroimaging. 2009 ; 19(1): 3–8.