Note that FDG hypometabolism has also been noted to involve the frontal and temporal lobe cortices in both HD patients and asymptomatic carriers [21]. MR Spectroscopy Head There is no relevant literature to support the use of MR spectroscopy of the brain in the initial imaging evaluation of a patient with chorea or suspected HD. MRI Functional (fMRI) Head There is no relevant literature to support the use of fMRI of the brain in the initial imaging evaluation of a patient with chorea or suspected HD. MRI Head MRI of the brain without IV contrast is the optimal imaging modality in patients with chorea or suspected HD, although it is often normal early on in the disease course of HD. Although often unnecessary, IV contrast may offer limited utility in certain circumstances when infectious or inflammatory conditions are among the differential diagnoses being considered. MRI findings of HD include progressive marked degeneration and atrophy of the neostriatum, particularly the head of the caudate nuclei (with enlargement of the frontal horns of the lateral ventricles), with associated abnormal signal (either T2 hyperintensity or hypointensity) [22-26]. Additionally, abnormal T2 hyperintensity may be seen in the putamen and can help to highlight more subtle changes of atrophy [22-25]. Although disproportionate volume loss of the neostriatum is the hallmark of HD, voxel-based morphometry has shown that patients with symptomatic and asymptomatic HD have significant reduction in volume in almost all brain structures when compared with normal age-matched controls [27,28]. Movement Disorders and Neurodegenerative Diseases HMPAO SPECT or SPECT/CT Brain There is insufficient evidence to support the use of Tc-99m HMPAO SPECT/CT of the brain in the initial evaluation of a patient with chorea or suspected HD. Variant 3: Parkinsonian syndromes. Initial imaging.
Movement Disorders and Neurodegenerative Diseases. Note that FDG hypometabolism has also been noted to involve the frontal and temporal lobe cortices in both HD patients and asymptomatic carriers [21]. MR Spectroscopy Head There is no relevant literature to support the use of MR spectroscopy of the brain in the initial imaging evaluation of a patient with chorea or suspected HD. MRI Functional (fMRI) Head There is no relevant literature to support the use of fMRI of the brain in the initial imaging evaluation of a patient with chorea or suspected HD. MRI Head MRI of the brain without IV contrast is the optimal imaging modality in patients with chorea or suspected HD, although it is often normal early on in the disease course of HD. Although often unnecessary, IV contrast may offer limited utility in certain circumstances when infectious or inflammatory conditions are among the differential diagnoses being considered. MRI findings of HD include progressive marked degeneration and atrophy of the neostriatum, particularly the head of the caudate nuclei (with enlargement of the frontal horns of the lateral ventricles), with associated abnormal signal (either T2 hyperintensity or hypointensity) [22-26]. Additionally, abnormal T2 hyperintensity may be seen in the putamen and can help to highlight more subtle changes of atrophy [22-25]. Although disproportionate volume loss of the neostriatum is the hallmark of HD, voxel-based morphometry has shown that patients with symptomatic and asymptomatic HD have significant reduction in volume in almost all brain structures when compared with normal age-matched controls [27,28]. Movement Disorders and Neurodegenerative Diseases HMPAO SPECT or SPECT/CT Brain There is insufficient evidence to support the use of Tc-99m HMPAO SPECT/CT of the brain in the initial evaluation of a patient with chorea or suspected HD. Variant 3: Parkinsonian syndromes. Initial imaging.