Wu, Kyle

Lay Summary Glioblastoma is an aggressive brain cancer, and it can be difficult to tell whether changes seen on scans after radiation treatment represent tumor growth or treatment-related effects. The authors of this study wanted to evaluate whether a specialized imaging test called PSMA PET could help define tumor boundaries for radiation planning and distinguish tumor progression from treatment-related changes. To do this, they performed PSMA PET scans in 27 patients with high-grade gliomas, including patients undergoing radiation planning and patients being evaluated for possible tumor recurrence. They found that tumors showed higher PSMA PET signal than surrounding tissue, that PSMA PET sometimes identified tumor beyond what was visible on standard MRI, and that it correctly distinguished tumor progression from treatment-related changes in most patients.

BACKGROUND AND OBJECTIVES: Lesions located in the retrosellar region, interpeduncular cistern, and petroclival region are among the most difficult to access in neurosurgery. Transcranial approaches are useful; however, the large distance between the surgeon and the lesion as well as the presence of major neurovascular structures surrounding the lesion may limit surgical exposure. A midline transsphenoidal route avoids transgression of the neurovascular plane and provides direct access to the interpeduncular cistern. To safely access the interpeduncular fossa, it requires mobilization of the pituitary gland. The pituitary hemitransposition technique permits mobilization of the gland, while preserving its venous drainage and arterial supply to the gland on one of its sides, preserving gland function. The authors aim to describe the intradural pituitary hemitransposition technique and to demonstrate its safe application for resection of skull base tumors in the retrosellar space. METHODS: The authors describe the surgical technique and illustrate its application in 5 cases of different types of skull base tumors, including a video demonstrating all the steps to perform this approach. In addition, the authors discuss the advantages and limitations of this technique compared with other approaches to the retrosellar space. RESULTS: The intradural pituitary hemitransposition technique was used to safely resect a chondrosarcoma, chordoma, craniopharyngioma, teratoma, and meningioma involving the parasellar and retrosellar spaces, while minimizing endocrine morbidity. We had one patient with mild, albeit permanent hyperprolactinemia and hypothyroidism after surgery. No other patients had permanent dysfunction related to surgery. CONCLUSION: The endonasal endoscopic intradural pituitary hemitransposition approach is an effective technique for resection of lesions located within the retrosellar and petroclival regions, allowing adequate exposure while potentially optimizing the preservation of the pituitary function.