Effectiveness of Bilateral Inferior Petrosal Sinuses Sampling in Tumor Lateralization: Intraoperative Findings and Postoperative Results

Abstract

Diagnosis and treatment of Cushing's disease (CD) is a demanding endeavor. We evaluated the effectiveness of inferior petrosal sinus sampling (IPSS) in preoperative tumor lateralization and surgical outcomes. Fifty-two consecutive patients with CD and normal magnetic resonance imaging (MRI) were enrolled between 2009 and 2015. Selective catheterization of petrosal sinuses for IPSS was performed. All patients underwent microsurgical dissection, and if a lesion was found, underwent lesion resection. Demographic, biochemical, and intraoperative findings were prospectively collected and reviewed 6 and 12 months postoperatively. Forty-five patients (86.4%) had clear lateralization while seven patients had bilateral elevation. Twenty-two patients (42%) were found to have a macroscopic lesion, defined as an abnormal tissue during microsurgical dissection, which was thus resected. No patient had a lesion larger than 4 mm. Eighty-one percent of patients had the lesion where IPSS had been predicted. Hemi-hypophysectomy was performed on twenty-eight patients based on IPSS findings, since no lesion was found. Eighty-six percent of patients with lesion resection had biochemical remission by 12 months. Biochemical remission was documented in 78 and 71% of patients who underwent hemi-hypophysectomy by 6 and 12 months, respectively. With careful microsurgical dissection, a macroscopic lesion could be found in a significant number of patients with normal MRI. When no lesion was found, we recommend performing a hemi-hypophysectomy based on IPSS findings, since prediction accuracy was high and remission rates were significant.

Prognostic usefulness of ACTH in the postoperative period of Cushing’s disease

“…A trans-naso-septal transsphenoidal approach was used, and all operations were performed by the same expert neurosurgeon. Although the guidelines do not establish a specific recommendation on the performance of hemi-hypophysectomy in those cases in which the adenoma is not identified during surgery, it seems a reasonable option to perform it based on BIPSS findings since prediction accuracy is high and remission rates are significant (42).…”