Early clinical and imaging (high-field MRI) diagnosis of Hallervorden-Spatz disease

Hallervorden-Spatz disease

Hallervorden-Spatz disease (HSD) is a rare disorder characterized by progressive extrapyramidal dysfunction and dementia. Hallervorden and Spatz first described the disease, in 1922 as a form of familial brain degeneration characterized by iron deposition in the brain. Here we present four HSD cases with different clinical pictures.

Relaxation and susceptibility MRI characteristics in Hallervorden-Spatz syndrome

PURPOSE

To evaluate the imaging characteristics of the brain with respect to relaxation and susceptibility in Hallervorden-Spatz syndrome (HSS), a rare inherited neurodegenerative disorder (also referred to as neurodegeneration with brain iron accumulation).

MATERIALS AND METHODS

We reviewed 13 affected individuals who satisfied the inclusion criteria for HSS. Clinically, the patients were divided into two groups: early-childhood onset (age of onset before 10 years) and late-childhood onset (age of onset after 10 years). MRI was performed on 1.5T MR equipment. The imaging protocol included spin-echo (SE) T1-weighted (T1W), turbo spin-echo (TSE) T2W, and fluid attenuated inversion recovery (FLAIR) sequences in all patients. Susceptibility-weighted imaging (SWI) included a fast low-angle shot (FLASH) sequence in 10 patients and a blood oxygen level-dependent (BOLD) sequence in two patients.

RESULTS

All of the patients showed hyperintensity on T1WI and hypointensity on T2WI in the globus pallidi (GPs) bilaterally. Central or anteromedial hyperintensity was found in all but one patient. FLASH showed augmented hypointensity in 10 patients, and BOLD showed bilateral striatonigral abnormal pigmentation in two patients. MR spectroscopy (MRS) showed normal spectra in four patients, and a reduced NAA/Cho ratio in two.

CONCLUSION

MRI showed prominent signal abnormalities in the GP bilaterally in HSS. T1WI showed hyperintensity in all cases of HSS in addition to the "eye-of-the-tiger" sign on T2WI. SWI, FLASH, and BOLD demonstrated mineral deposition in the GP better than conventional imaging. Involvement of the striatonigral pathways was demonstrated for the first time on BOLD SWI.

Staged bilateral stereotactic pallidothalamotomy for life-threatening dystonia in a child with Hallervorden-Spatz disease

Hallervorden-Spatz disease (HSD) is a rare disorder characterized by progressive motor dysfunction and dementia. Dystonia is the most prominent and disabling symptom, responding only to a modest extent to pharmacological therapy. At the moment, only a few cases have been reported to improve dystonia and even fewer to resolve status dystonicus for a longer period in children. The authors present the case of a 10-year-old boy who had progressive generalized dystonia, resulting in spontaneous femur fracture and life-threatening swallowing and respiratory disability. As a rescue solution, staged bilateral pallidothalamotomy was performed. Postoperatively, Burke-Fahn-Marsden Dystonia Rating Scale and Dystonia Disability Rating Scale improved (from 116 and 30 points to 41 and 18 points, respectively) and painful dystonia was resolved, which was still continuous 4 years later (47 and 20 points). Stereotactic staged bilateral pallidothalamotomy should be considered as a potential treatment in the management of life-threatening generalized dystonia related to HSD.

Neuro-ophthalmologic and electroretinographic findings in pantothenate kinase-associated neurodegeneration (formerly Hallervorden-Spatz syndrome)

PURPOSE

The onset of pantothenate kinase-associated neurodegeneration (PKAN) occurs in the first and second decade of life and a pigmentary retinal degeneration is a feature of the disorder. Since the neuro-ophthalmologic and electroretinographic (ERG) features have never been well delineated, we describe them in 16 patients with PKAN.

DESIGN

Observational case series.

METHODS

Sixteen patients with genetic and neuroimaging-confirmed PKAN were examined. Ten underwent neuro-ophthalmologic examination and all had ERGs.

RESULTS

Of the 10 who underwent neuro-ophthalmologic examination, all showed saccadic pursuits and eight showed hypometric or slowed vertical saccades. Seven of eight had inability to suppress the vestibulo-ocular reflex; two patients could not cooperate. Two had square wave jerks and four had poor convergence. Vertical optokinetic responses were abnormal in five, and two patients had blepharospasm. Eight patients had sectoral iris paralysis and partial loss of the pupillary ruff consistent with Adie's pupils in both eyes. Only four of 10 examined patients showed a pigmentary retinopathy, but 11 of 16 had abnormal ERGs ranging from mild cone abnormalities to severe rod-cone dysfunction. No patient had optic atrophy. The PANK2 mutations of all of the patients were heterogeneous.

CONCLUSIONS

Adie's-like pupils, abnormal vertical saccades, and saccadic pursuits were very common. These findings suggest that mid-brain degeneration occurs in PKAN more frequently than previously thought. ERG abnormalities were present in approximately 70% and no patient had optic atrophy. Although genotype-ocular phenotype correlations could not be established, allelic differences probably contributed to the variable clinical expression of retinopathy and other clinical characteristics in these patients.

[Hallervorden Spatz syndrome: magnetic resonance findings. Case report]

Hallervorden-Spatz syndrome is a neurodegenerative disease, autosomic recessive with two clinical features: early and late onset. Psychiatric, pyramidal and extrapyramidal signs are present in the late subtype. We report the case of a 41-old woman with extrapyramidal signs. Magnetic resonance imaging (MRI) showed the eye-of-the-tiger sign in the medial globus pallidus. This is due to a gliosis (increased signal) and accumulation of surrounding iron (decreased signal intensity) in long TR sequences. There is a strong relationship between MRI findings and the gene mutation responsable for this disease. It makes the MRI sensible for diagnosing this syndrome.

Compound heterozygous PANK2 mutations confirm HARP and Hallervorden-Spatz syndromes are allelic

The authors describe a patient with hypoprebetalipoproteinemia, acanthocytosis, retinitis pigmentosa, and pallidal degeneration (HARP) who has two compound heterozygote mutations of the PANK2 gene. IVS4-1 G>T segregates with the lipid and erythrocyte changes in the mother and sister. No other family members have the lipid, erythrocyte, or clinical abnormalities. The father and two brothers are heterozygous for Met327Thr. One other mutation has been found in this PANK2 region associated with the HARP phenotype, suggesting a local genotype effect.

Clinical heterogeneity of neurodegeneration with brain iron accumulation (Hallervorden-Spatz syndrome) and pantothenate kinase-associated neurodegeneration

Hallervorden Spatz syndrome (HSS), also referred to as neurodegeneration with brain iron accumulation (NBIA), is a rare inherited neurodegenerative disorder with childhood, adolescent, or adult onset. Patients with HSS/NBIA have a combination of motor symptoms in the form of dystonia, parkinsonism, choreoathetosis, corticospinal tract involvement, optic atrophy, pigmentary retinopathy, and cognitive impairment. After the recent identification of mutations in the PANK2 gene on chromosome 20p12.3-p13 in some patients with the HSS/NBIA phenotype, the term pantothenate kinase-associated neurodegeneration (PKAN) has been proposed for this group of disorders. To characterize clinically and genetically HSS/NBIA, we reviewed 34 affected individuals from 10 different families, who satisfied the inclusion criteria for NBIA. Relatives of patients who had clinical, magnetic resonance imaging (MRI), or pathological findings of NBIA were included in the study. Four patients were found to have mutations in the pantothenate kinase 2 (PANK2) gene. We compared the clinical features and MRI findings of those with and without PANK2 mutations. The presence of mutation in the PANK2 gene is associated with younger age at onset and a higher frequency of dystonia, dysarthria, intellectual impairment, and gait disturbance. Parkinsonism is seen predominantly in adult-onset patients whereas dystonia seems more frequent in the earlier-onset cases. The phenotypic heterogeneity observed in our patients supports the notion of genetic heterogeneity in the HSS/NBIA syndrome.

Familial pediatric rapidly progressive extrapyramidal syndrome: is it Hallervorden-Spatz disease?

The clinical features of two children of a family with rapidly progressive extrapyramidal-pyramidal-dementia complex have been described. Inheritance seems most likely to be autosomal recessive. Magnetic resonance imaging results of brain were negative. Even so, the authors argued in favor of a diagnosis of Hallervorden-Spatz disease because the cases fulfilled the clinical criteria for diagnosis of this disease. Apart from the negative magnetic resonance findings, the other unusual feature was the early development of levodopa-induced dyskinesia. Few conditions need to be considered in the differential diagnosis of a childhood-onset rapidly progressive extrapyramidal syndrome. Such conditions include Wilson's disease, Hallervorden-Spatz disease (HSD), juvenile form of Huntington's disease, juvenile neuronal ceroid lipofuscinosis, early-onset Machado-Joseph disease neuroacanthocytosis, storage disorders, and variant form of dopa-response dystonias (DRD). Rarer conditions are Leigh's disease, Lafora body disease, and dentato-rubro-pallido-luysian atrophy. HSD is a rare disorder characterized by progressive extrapyramidal dysfunction and dementia. Onset is most commonly in late childhood or early adolescence. The disease can be familial or sporadic. When familial, it is inherited recessively and has been linked to chromosome 20. Recently, a mutation in the pantothenate kinase (PANK2) gene on band 20pl3 has been described in patients with typical HSD. HSD produces typical magnetic resonance imaging (MRI) changes in brain, aiding in antemortem diagnosis. The typical finding is of bilaterally symmetrical hyperintense signal changes in the external segment of globus pallidus, with surrounding hypointensity on T(2)-weighted image. These imaging features are fairly diagnostic and have been termed the "eye-of-the tiger sign". The hyperintensity represents pathologic changes, including gliosis, demyelination, neuronal loss, and axonal swelling, and the surrounding hypointensity is caused by loss of signal secondary to iron deposition. Described herein are the clinical aspects of a family with autosomal recessive inheritance with rapidly progressive extrapyramidal-pyramidal-dementia complex but with negative brain MRI results. The diagnosis should be considered a variant form of HSD.

Iron overload, oxidative stress, and axonal dystrophy in brain disorders

Hallervorden-Spatz syndrome is an autosomal-recessive brain disorder with signs of extrapyramidal dysfunction and mental deterioration, which associate with iron accumulation in globus pallidus and substantia nigra pars reticulata. Studies of oxidant stress in parkinsonian animal models suggest a linkage of iron overload to axonal dystrophy. Redox cycling of iron complexes (i.e., ferrous citrate and hemoglobin) increases hydroxyl radicals, lipid peroxidation, axonal dystrophy, and necrotic or apoptotic cell death. An increase of oxidative stress in the basal ganglia because of redox cycling of iron complexes leads to dopamine overflow and psychomotor dysfunction. Iron overload-induced axonal dystrophy has been demonstrated consistently using in vitro and in vivo models with a prominent feature of lipid peroxidation. This iron-induced oxidative stress is often accentuated by ascorbate and oxidized glutathione, although it is suppressed by the following antioxidants: S-nitrosoglutathione or nitric oxide, MnSOD mimics, manganese, U-78517F, Trolox, and deferoxamine. Preconditioning induction of stress proteins (i.e., hemeoxygenase-1 and neuronal nitric oxide synthase) and hypothermia therapy suppress the generation of toxic reactive oxygen, lipid, and thiol species evoked by bioactive iron complexes in the brain. Finally, combined antioxidative therapeutics and gene induction procedures may prove to be useful for slowing progressive neurodegeneration caused by iron overload in the brain.

Adult-onset Hallervorden-Spatz syndrome presenting as cortical dementia

The authors examined behavioral and pathophysiologic substrates in a patient with adult-onset Hallervorden-Spatz syndrome who presented with insidious cognitive decline but no motor impairment. The authors combined longitudinal case history and serial neuropsychologic testing with functional neuroimaging (positron emission tomography), structural neuroimaging (magnetic resonance imaging), and brain tissue analyses. Serial assessments of a 29-year-old woman showed progressive dementia. Marked cognitive and behavioral deficits were seen on neuropsychologic testing, corresponding to striking cortical abnormalities on positron emission tomography, magnetic resonance imaging, and histopathologic studies. Typical motor manifestations of the disorder did not emerge until the patient was 34 years old, 5 years after the onset of cognitive symptoms. Hallervorden-Spatz syndrome should be considered in the differential diagnosis of progressive cortical dementia in a young adult, even in the absence of motor dysfunction.

Hallervorden-Spatz disease: two new early childhood onset cases

Hallervorden-Spatz disease is a rare, autosomal-recessive hereditary condition characterized by early onset of progressive movement alterations such as dystonia, rigidity, and choreoathetosis, which is usually associated with pyramidal signs and mental deterioration. The authors report two cases for which diagnosis of Hallervorden-Spatz disease was based on clinical manifestations that appeared during the first year of life, illness progression, and late-stage magnetic resonance imaging findings. The possibility that these two cases, along with other previously described rare instances with similar clinical features, be considered as a variant of subtype of the early-onset type of Hallervorden-Spatz disease is suggested. The need to differentiate these cases from cases of static encephalopathy with mental retardation and motor impairment is also stressed.

High resolution MRI of the deep gray nuclei at 8 Tesla

PURPOSE

High resolution MR images obtained from a normal human volunteer at 8 T are utilized to describe the appearance of iron-containing deep gray nuclei at this field strength.

METHOD

High resolution (1,024 x 1,024 matrix) near-axial gradient echo images of the deep gray nuclei were acquired on a human volunteer by using an 8 T scanner. The images were acquired using a transverse electromagnetic resonator operating in quadrature. The following parameters were utilized: TR = 750 ms, TE = 17 ms, flip angle = 45 degrees, receiver bandwidth = 50 kHz, slice thickness = 2 mm, FOV = 20 cm. The 8 T images were reviewed and correlated to the known anatomy of the deep nuclei by comparing them with images observed at lower field strength, published diagrams, and histologic sections. In addition, the appearance of the nuclei was related to the known imaging characteristics of brain iron at lower fields.

RESULTS

The caudate, globus pallidus, putamen, thalami, substantia nigra, and red nuclei were clearly identified. The structures with the highest levels of iron, the globus pallidus, substantia nigra, and red nuclei, demonstrated significantly decreased signal, providing a map of iron distribution in the human brain.

CONCLUSION

Preliminary imaging at 8 T demonstrates the ability to acquire ultra high resolution images of the deep nuclei, with signal characteristics believed to represent the distribution of brain iron. This may prove to be important in the early diagnosis of several neurodegenerative disorders.