Evaluating the Performance of Intraoperative Ultrasound in Treating Pituitary Adenomas Through the Endoscopic Endonasal Route

BACKGROUND AND OBJECTIVES: Resecting pituitary microadenomas and macroadenomas with extrasellar extensions through the endoscopic endonasal route often requires adjunctive tools to assess the anatomy, maximize resection, and preserve the functional integrity of the gland. Intraoperative ultrasound (IOUS) is a cost-effective tool that is routinely used in neuro-oncology. With the advancement of this technique, smaller and slender probes have been developed that are useful in endoscopic approaches. The aim of this study was to assess the usefulness of IOUS in the endoscopic resection of pituitary adenomas and evaluate its effect on lesion localization, residual detection, and clinical outcome. METHODS: This is a retrospective study on 79 cases (83 surgeries) between January 2023 and December 2024 that underwent endoscopic endonasal resection for pituitary adenomas using IOUS. The performance of IOUS in detecting residual disease was compared with postoperative MRI. RESULTS: Gross total resection (GTR) was achieved in 77.1% cases and average residue volume was 2.9 cc. IOUS prevented early termination of resection in 10 cases and thus helped achieve GTR in each of them. A total of 13 residual disease (15.6%) was missed on IOUS, average residue volume missed was 0.7 cc, and the lateral compartment of the cavernous sinus was the most common site that alluded detection. The specificity of IOUS in detecting residual disease was 98.5%, while the sensitivity was 27.8%. Disease extension into both cavernous sinus and suprasellar sellar cistern significantly affected the ability of the IOUS to identify residual disease ( P = .002), and it was more likely to miss residual diseases in cases of giant adenomas than smaller pituitary adenomas. CONCLUSION: IOUS helps achieve GTR without compromising clinical outcomes.