The patient, a 25-year-old woman, was seen at our hospital 6 years ago, complaining of weakness and stiffness in the left side of the body and left limbs for 1 + years. Physical examination revealed atrophy of the upper and lower limbs on the left side. Neurological examination showed increased muscle tone in the left-side body and limbs, bradykinesia, decreased muscle strength in the left-side body and limbs, and positive Hoffman's sign in the left limbs. Laboratory tests, including alpha fetoprotein (AFP), β-human chorionic gonadotropin (HCG) and cerebrospinal fluid examination, did not reveal any abnormal results. Head MRI showed right cerebral hemiatrophy. Head and neck CT angiography did not show obvious abnormality. According to the medical history and examination results, diagnosis of hemiparkinsonism-hemiatrophy syndrome was made. Through close follow-up for 6 years, we noticed that the parkinsonism remained unilateral and stable, and the contralateral cerebral hemiatrophy did not show obvious progress. However, brain perfusion MRI showed hypoperfusion of the right basal ganglia. The discovery of hypoperfusion in the basal ganglia may help explore the etiology of hemiparkinsonism-hemiatrophy syndrome. 患者，25岁女性，6年前因“左侧肢体无力伴肢体活动僵硬1+年”于我院就诊，查体发现左侧上下肢萎缩，神经专科查体见左侧肢体肌张力增高、运动迟缓、左侧肢体肌力下降、Hoffmann征阳性。甲胎蛋白（alpha fetoprotein，AFP）、β-人绒毛膜促性腺激素（human chorionic gonadotropin，HCG）及脑脊液检查均未见异常。头部MRI显示右侧脑萎缩。CT头颈部血管三维增强重建扫描未见明显异常。结合病史及检查，该患者诊断为偏侧萎缩偏侧帕金森综合征。患者于我院定期随访，6年来患者帕金森综合征症状稳定且局限于左侧，右侧脑萎缩未见明显进展。MRI脑灌注成像显示患者右侧基底节区低灌注。基底节区低灌注的发现可能会有助于探索偏侧萎缩偏侧帕金森综合征的病因。

There is no established pathogenesis of hemiparkinsonism-hemiatrophy syndrome (HPHA), and the varied clinical presentations have been reported in several case studies. To the best of our knowledge, the present report describes the first case of HPHA with unusual brain imaging findings. A 20-year-old man presented with a 6-month history of weakness and clumsiness in his right limbs. He showed right-sided parkinsonism with dystonic hand posture; however, body asymmetry was not noted. Brain imaging revealed hemiatrophy of the left hemisphere subcortical structures and brainstem, and iron deposition in the left globus pallidus and substantia nigra. In addition, dopamine transporter imaging demonstrated normal presynaptic dopaminergic function. The patient was treated with levodopa, which had little to no effect. This case demonstrates the unique imaging characteristics of HPHA associated with widespread brain hemiatrophy and iron deposition. Further studies are needed to elucidate the diagnostic criteria for this heterogeneous syndrome.

Hemiparkinsonism-hemiatrophy syndrome (HPHA) and hemidystonia-hemiatrophy syndrome (HDHA) are rare movement disorders composed of hemidystonia or hemiparkinsonism that present with unilateral limb, face, trunk, or cerebral hemiatrophy and mostly occur following head trauma or postanoxic events. However, relatively little is known about the pathogenesis of these conditions. In our case series, we present three HPHA patients and one HDHA patient who underwent detailed neuropsychological, radiological, motor, and non-motor functional assessments with a mean follow-up of 2 years. We followed two patients who showed differences in their progression for more than 2 years: one barely progressed with no treatment, and the other exhibited levodopa-induce dyskinesia (LID) and definitive progression while receiving multiple adjunctive therapies. In addition, we performed positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) and 18F-dihydroxyphenylalanine (DOPA) in one HPHA patient who showed bilaterally symmetrical uptake of FDG with no significant increase or decrease in the cerebral hemispheres, including the striatum, but exhibited a significant reduction in the uptake of 18F-DOPA in the contralateral posterior striatum. In this study, we followed HPHA patients who showed different disease courses to explore the clinical characteristics and pathogenesis of HPHA and HDHA and illustrate the clinical heterogeneity of these diseases.