Percutaneous Ethibloc injection in aneurysmal bone cysts

Objective. To investigate whether the injection of Ethibloc into aneurysmal bone cysts can be an effective treatment modality. Design and patients. Ethibloc is an alcoholic solution of zein (corn protei n) which has thrombogenic and fibrogenic properties. Ten patients with aneu rysmal bone cysts were treated with CT-guided percutaneous injection of Eth ibloc into the cyst cavity. Ethibloc injection was the primary treatment in five patients. Four patients had recurrence following previous curettage a nd bone grafting and one patient had not responded to injection into the le sion of autologous iliac crest bone marrow aspirate. Three patients needed a second injection. The median follow-up was 27 (6-60) months. Results and conclusion. Symptoms were relieved in all patients. At imaging, seven patients had resolution of the lesion and three had partial response at the most recent follow-up. Complications consisted of a local transitor y inflammatory reaction in two patients and an aseptic abscess in one patie nt. This relatively simple, minimally invasive procedure makes an operation unnecessary by stopping the expansion of the cyst and inducing endosteal n ew bone formation. This technique may be used as the primary management of aneurysmal bone cysts excluding spinal lesions.