Anatomical Differences In Sphenoid Sinus During Endoscopic Trans-Sphenoidal Surgery: Comparison Between Non-Functioning PiTNET And GH-Secreting PiTNET

In surgical practice during endoscopic endonasal approach (EEA), Growth Hormone-secreting Pituitary Neuroendocrine Tumors (GH-secreting PitNET) patients show morphologic differences in the nasal cavities and sinuses, leading to a narrower surgical field and a carotid prominence and potentially increasing the complexity of the surgical and the risk of complications. The aim of the study is to evaluate the anatomical differences of the sphenoid sinus between patients with GH-secreting PitNETs and patients with non-functioning Pituitary Neuroendocrine Tumors (NF-PitNET) underwent EEA. This is a monocentric retrospective study conducted at author's institution. The minimum intercarotid distance (ICS), the largest diameter of the sphenoid sinus (DSS) and the distance between vomer and clivus (VCD) were collected and compared. Presence, localization and course of intersphenoid sinus septum (ISS) were also evaluated. 100 consecutive patients were identified: 57 males (57%) and 43 females (43%), with a mean age of 55 years. 60 patients had NF-PitNET (60%) and 40 had GH-secreting PitNET (40%). GH-secreting PitNET group presented inferior values of ICD (16.8±3.94 mm vs. 20.4±3.94 mm, p<0.001), DSS (32.5±9.81 mm vs. 38.6±11.03 mm, p=0.006) and VCD (25.5±6.96 mm vs. 29.6±8.47 mm, p=0.012) compared to NF-PitNET group. ISS showed no differences between the two groups. ICD, DSS and VCD resulted smaller in acromegalic patients, confirming that patients with GH-secreting PitNETs have a narrower surgical field. A meticulous anatomical preoperative planning and neuronavigation are important to recognize the sphenoid anatomical landmarks in order to reduce the risk of complications, especially in acromegalic patients.