Objective: To evaluate left atrial volume and function in patients with paroxysmal atrial fibrillation (AF) combined with left atrial appendage thrombosis and patients with paroxysmal AF without left atrial appendage thrombosis by 3-dimensional speckle tracking imaging (3D-STI), and to explore the application value of this set of parameters in the evaluation of left atrial function in patients with paroxysmal AF. Materials and Methods: A total of 40 patients with paroxysmal AF admitted from December 2018 to December 2020 were selected as the observation group. All patients with paroxysmal AF in the observation group underwent transesophageal echocardiography. According to the presence of left atrial appendage thrombosis, the patients were divided into the AF without thrombosis group (24 cases) and the AF with thrombosis group (16 cases). Thirty normal people were selected as control group who were chosen as having no heart-related disease. The left atrial volume parameters (Left atrial maximum volume LAVmax, Left atrial minimum volume LAVmin, Left atrial volume before atrial contraction LAVpre-A, Left atrial stroke volume LAEV), left atrial ejection fraction (LAEF) and left atrial strain parameters (Left atrial reservoir longitudinal strain LASr, Left atrial conduit longitudinal strain LAScd, Left atrial contraction longitudinal strain LASct, Left atrial reservoir circumferential strain LASr-c, Left atrial conduit circumferential strain LAScd-c, Left atrial contraction circumferential strain LASct-c) of the 3 groups were measured by 3D-STI. Results: With the progression of paroxysmal AF, the left atrial volume increased, and the reservoir, conduit and contractile function were damaged. The left atrial volume continued to increase, and the reservoir, conduit and contractile function further decreased significantly in patients with AF combined with left atrial appendage thrombosis. LAEF was positively correlated with LASr and LASr_c. Conclusion: Real-time 3-dimensional spot tracking imaging (3D-STI) can evaluate the changes in left atrial volume and function in patients with paroxysmal AF, and has a certain reference value for clinical judgment of disease progression and prognosis.

Rationale: Meningeal melanocytosis is an exceedingly rare diffuse leptomeningeal melanocytic disorder that frequently mimics meningeal carcinomatosis or chronic infectious meningitis on conventional magnetic resonance imaging (MRI), posing substantial diagnostic challenges. This report aims to enhance clinical awareness of this condition and underscore the indispensable role of radiologic–pathologic correlation in achieving a definitive diagnosis. Patient concerns: A 19-year-old male presented with a 3-month history of progressive headache, nausea, vomiting, and one episode of generalized tonic-clonic seizure. Neuroimaging demonstrated diffuse linear leptomeningeal enhancement without restricted diffusion or conspicuous T1 shortening. Cerebrospinal fluid (CSF) analysis, bacterial and fungal cultures, next-generation sequencing (NGS), and positron emission tomography–computed tomography (PET-CT) were all non-diagnostic, and empirical anti-infective therapy failed to halt disease progression. Diagnoses: Following comprehensive exclusion of infectious, inflammatory, autoimmune, and neoplastic etiologies, stereotactic leptomeningeal biopsy was performed. Histopathology revealed diffuse proliferation of cytologically bland melanocytes within the leptomeninges; immunohistochemistry confirmed S-100, HMB45, and Melan-A positivity with a Ki-67 proliferative index of approximately 1% and wild-type BRAF V600E status, establishing a definitive diagnosis of meningeal melanocytosis. Interventions: The patient was treated with intravenous dexamethasone (10 mg/day) to manage cerebral edema and levetiracetam (500 mg twice daily) for seizure prophylaxis. Referral to a specialized neuro-oncology center was arranged for evaluation of definitive therapy, including potential whole-brain radiotherapy or intrathecal chemotherapy. Outcomes: Symptoms improved markedly following biopsy and initiation of corticosteroid therapy; headaches resolved, vomiting ceased, and no further seizures occurred during hospitalization. The patient was discharged neurologically intact on day 15 with a healed surgical wound, though long-term follow-up imaging was unavailable due to loss to specialized follow-up. Lessons: Meningeal melanocytosis may present without classic melanin-related T1 hyperintensity, rendering it indistinguishable from carcinomatosis on standard MRI sequences. When noninvasive investigations including CSF studies, NGS, and PET-CT are inconclusive, timely tissue biopsy is warranted. Incorporating susceptibility-weighted imaging and molecular testing for GNAQ/GNA11 mutations into the diagnostic workup may improve early and accurate identification of this rare condition.