A retrospective analysis was conducted on the neuroimaging features of white matter lesions related to patent foramen ovale and clinical characteristics (age, sex, history of hypertension and diabetes, etc.) of patients who underwent patent foramen ovale closure surgery at Fuwai Hospital, Chinese Academy of Medical Sciences, from February 2021 to June 2025. All patients were confirmed to have right-to-left shunt by contrast-enhanced transthoracic echocardiography and completed brain MRI examination. According to the results of contrast-enhanced transthoracic echocardiography, patients were divided into 2 groups (large-shunt group and non-large-shunt group). The distribution characteristics of white matter lesions were investigated from multiple dimensions, including anterior/posterior circulation, left/right hemisphere, and single/multiple lesions. A total of 118 patients were screened, among whom 100 with complete clinical data were included in the study. The age was (45.4±9.9) years. There were 62(62%) cases in the large-shunt group and 38(38%) cases in the non-large-shunt group. No statistically significant differences were found between the 2 groups in terms of age, gender, or history of hypertension, diabetes, stroke or transient ischemic attack (TIA). The proportion of multiple white matter lesions in the large-shunt group was significantly different [59.7%(37/62) vs 39.5%(15/38), P=0.049], as was the proportion of bilateral hemispheric distribution [62.9%(39/62) vs 42.1%(16/38), P=0.042]. The proportion of lesions distributed in the right hemisphere was higher [66.1%(41/62) vs 47.4%(18/38)], but the difference did not reach statistical significance (P=0.064). Among patients with a history of stroke or TIA, the proportions of multiple, bilateral, and involvement of both anterior and posterior circulation white matter lesions were significantly higher than those without such histor[66.1%(39/59) vs 31.7%(13/41), 67.8%(40/59) vs 36.6%(15/41), 62.7%(37/59) vs 26.8%(11/41), all P<0.01]. No statistically significant difference in white matter lesions distribution was observed between patients with and without a history of migraine. Patients with patent foramen ovale and a large right-to-left shunt are more likely to present with bilateral and multiple cerebral white matter lesions on brain MRI, and these white matter lesions are more prone to occur in the right hemisphere.

Polycythemia vera (PV) is a clonal myeloproliferative neoplasm primarily caused by the JAK2V617F mutation, present in 95% of patients. It results in erythropoietin-independent hematopoietic proliferation, erythrocytosis, increased hematocrit (Hct), leukocytosis, thrombocytosis, and hyperviscosity, predisposing patients to thrombotic events and neurologic deficits, including erythromelalgia and pruritus. Neurologic manifestations can occur, such as transient ischemic attack (TIA) and stroke. We report an 83-year-old woman, PV patient who presented with chorea and magnetic resonance imaging (MRI) of her brain showed pachymeningeal enhancement (dural-arachnoid enhancement); this radiological finding is most commonly described in intracranial hypotension, autoimmune conditions, infection, and neoplastic processes and has not been reported in PV. Laboratory findings included complete blood count (CBC) showed severe erythrocytosis, moderate leukocytosis with moderate, mild thrombocytosis; bone marrow (BM) aspiration and biopsy showed hypercellular BM and marked megakaryocytic hyperplasia; and positive JAK2V617F mutation with 80% JAK2 DNA, suggestive of PV as the underlying cause. The patient underwent phlebotomy and was started on Aspirin. Following treatment, she showed dramatic improvement in choreiform movements. Hydroxyurea 500 mg three times daily was subsequently added, leading to complete hematologic response and resolution of pachymeningeal thickening on follow up MRI. This case suggested association between polycythemia vera and choreiform movements and a possible mechanism is proposed.