Introduction Intracranial aneurysms with a radiological sign of a donut are a medical priority and have been described in a small number of cases. This radiological sign occurs in aneurysms in which there is partial thrombosis inside aneurismal sac and circular laminar flow between the aneurismal wall and the thrombus in its center. Consequently, there is a central contrast-filling defect of the aneurysm sac observed on different angiographic imaging methods. Case outline We present a 35-year-old female patient admitted for examination due to frequent headaches, visual disturbances on the left and loss of sight on the right eye. Digital subtraction angiography (DSA) showed an aneurysm on the right internal carotid artery measuring 25.6 × 25 mm, while neck measured 11 mm and included part of the C6 and C7 segments. Treatment decision was made that placing a flow-diverting stent across the aneurysm neck would be most beneficial in this case. After the procedure, the patient was discharged in the same general condition as she was before admission to the hospital. Seven months after the intervention, she reported for her first DSA control examination. Normal position of the left A1 segment was demonstrated, suggesting shrinkage of the aneurysm sac. An improvement of vision on both eyes was stated. Conclusion: We present a patient with a "donut" aneurysm on the internal carotid artery, successfully treated with a flow-diverting stent.