Abstract: Objective To analyze the clinical characteristics and associated projnostic factors of cranio-orbital meningiomas. Design Retrospective study. Participants Fifty-six patients with 27 male and 29 female were recruited who were diagnosed to be cranio-orbital meningiomas by surgery or biopsy. Methods The clinical characteristics, imaging features, involvement lesions, histopathological grading, Ki-67 values, and treatment schemes of all the cases were reviewed retrospectively. The information of tumor progression (TP) and time to tumor progression was also obtained. The correlation of those variables and TP was analyzed by Logistic multivariate analysis. Main Outcome Measures clinical manifestation; MRI features (including T1WI and T2WI signal changes, enhancement degree, enhancement uniformity, and invasion range); the change of adjacent bone showed by CT bone window; treatment plan; histopathological grading; Ki-67 index; tumor progression and progression time. Results 35 cases (62.5%) had exophthalmos and 23 cases (41.1%) had decreased vision. The most involvement lesion of cranio-orbital meningioma was orbital apex (82.1%，46/56). 89.3% of cases showed iso-intensity on T1WI(50/56), and 80.4% of cases with slight hyper-intensity on T2WI(45/56), all the tumors (100%) showed obvious enhancement, and 16.1% of cases (9/56) showed heterogeneous enhancement after contrast media injection. Surgery is the most common treatment (98.2%, 55/56), with 11 cases (19.6%) performed adjuvant radiotherapy after operation. 42 cases had histopathogical grading WHO-I (75%), and 14 cases with WHO-II or III (25%). Ki-67 index was obtained in 38 cases with 6 cases showing the values of ≥5% (15.8%). Logistic regression analysis showed that the variables including operation method, enhancement pattern on MRI, brain involvement, WHO grading and Ki-67 value were correlated with TP significantly. Conclusion Orbital apex involvement is the most common feature of cranio-orbital meningiomas. Total tumor resection, homogeneous enhancement on MRI, no brain involvement, grading WHO-I and Ki-67 <5% were associated with better tumor prognosis significantly. (Ophthalmol CHN, 2023, 32: 39-44)

Key words: cranio-orbital meningioma, magnetic resonance imaging, treatment