Patient Population and Study Criteria

This is a retrospective case series of 17 consecutive patients who underwent brain surgery aided by IOUS for different brain tumors at our institution from January 2021 to September 2021. All patients underwent IOUS during surgical resection of different intracranial lesions: six patients suffered from meningioma, five from glioblastoma, one from breast cancer cerebellar metastasis, two from lung cancer metastases, one from colon cancer metastasis, one from embryonal tumor (medulloblastoma), and one from cerebellar diffuse large B-cell lymphoma. Moreover, one of these patients who was affected by right extra-axial lesion underwent ultrasound evaluation also before surgery, due to a previous iatrogenic skull defect.

The patients’ eligibility criteria were the following: the presence of brain lesion, the surgical indications for craniotomy, a craniotomy large enough for the probe placement, patient’s given informed consent, and the presence of a good acoustic window for ultrasound acquisition after craniotomy. Patients who did not meet such eligibility criteria were excluded.

The indications to the use of intraoperative ultrasound were the following: preoperative evaluation, anatomical study of tumoral lesion, evaluation of the relationships between tumor and brain parenchyma, study of the tumor stiffness, study of the tumor vascularization, study of brain vessels, and study of the residual tumor volume.