Objective To evaluate the clinical value of optic nerve sheath diameter(ONSD)measured on thin-slice CT scan in the diagnosis and prognostic assessment of cerebral venous sinus thrombosis(CVST).Methods The clinical data of patients with CVST,who were admitted to the First Affiliated Hospital of Nanjing Medical University of China to receive treatment from January 1,2016 to December 31,2022,were retrospectively analyzed.The difference in ONSD was compared between CVST patients and normal population,the postoperative changes in ONSD was analyzed.Results A total of 49 patients with CVST(CVST group)and 49 normal persons having no brain disorders(control group)were enrolled in this study.In CVST group,the preoperative ONSD was(5.33±0.50)mm,which was significantly higher than(4.40±0.40)mm in control group(P＜0.001),the postoperative ONSD remarkably decreased to(4.98±0.59)mm(P＜0.01).The difference value between postoperative ONSD and preoperative ONSD in the patients receiving pure anticoagulation treatment was not statistically significant different from that in the patients receiving endovascular treatment[(-0.43±0.22)mm vs.(-0.40±0.42)mm,P=0.84].The preoperative ONSD in the patients having intracranial hemorrhage and in the patients having no intracranial hemorrhage was(5.26±0.51)mm and(5.41±0.49)mm respectively(P=0.31),and the difference value between postoperative ONSD and preoperative ONSD was(-0.39±0.40)mm and(-0.45±0.25)mm respectively(P=0.66).At the three-month follow-up visit,the difference in ONSD between the patients having a good prognosis(mRS score being 0-2 points)and the patients having a poor prognosis was not statistically significant(P＞0.05).Conclusion ONSD that is measured on plain head CT scan can be used as a response indicator of elevated intracranial pressure in CVST patients,which can be used to monitor the changes in intracranial pressure before and after treatment,but its value in assessing the curative efficacy of different therapeutic methods needs to be further explored.