Dumbbell-shaped pituitary adenomas: prognostic factors for prediction of tumor nondescent of the supradiaphragmal component from a multicenter series

OBJECTIVE Dumbbell-shaped pituitary adenomas (DSPAs) are a subgroup of macroadenomas with suprasellar extension that are characterized by a smaller diameter at the level of the diaphragma sellae opening compared with the supradiaphragmal tumor component (SDTC). Hence, DSPAs may be particularly prone to a nondescending suprasellar tumor component and risk for residual tumor or postoperative bleeding. METHODS A multicenter retrospective cohort analysis of 99 patients with DSPA operated on via direct endoscopic endonasal transsphenoidal approach between 2011 and 2020 was conducted. Patient recruitment was performed at two tertiary care centers (Medical University of Vienna and University of Southern California) with expertise in endoscopic skull base surgery. DSPA was defined as having a smaller diameter at the level of the diaphragma sellae compared with the SDTC. RESULTS On preoperative MRI, all DSPAs were macroadenomas (maximum diameter range 17–71 mm, volume range 2–88 cm3). Tumor descent was found in 73 (74%) of 99 patients (group A), and nondescent in 26 (26%) of 99 patients (group B) intraoperatively. DSPAs in group A had a significantly smaller diameter (30 vs 42 mm, p < 0.001) and significantly smaller volume (10 vs 22 cm3, p < 0.001) than those in group B. The ratio of the minimum area at the level of the diaphragmal opening in comparison with the maximum area of the suprasellar tumor component ("neck-to-dome area") was significantly lower in group A than in group B (1.7 vs 2.7, p < 0.001). Receiver operating characteristic curve analysis revealed an area under the curve of 0.75 (95% CI 0.63–0.87). At a cutoff ratio of 1.9, the sensitivity and specificity for a nondescending suprasellar tumor component were 77% and 34%, respectively. CONCLUSIONS In the present study, the neck-to-dome area ratio was of prognostic value for prediction of intraoperative tumor nondescent in DSPAs operated on via a direct endonasal endoscopic approach. Pituitary adenoma SDTC nondescent carried the inherent risk of hemorrhagic transformation in all cases.

Coexistence of Ectopic Posterior Pituitary and Sellar/Suprasellar Arachnoid Cyst: A Case Report

Background: The ectopic posterior pituitary (EPP) is a rare condition characterized by the ectopic location of the posterior pituitary lobe associated with varying degrees of stalk anomalies. The arachnoid cysts (AC) are benign lesions of the arachnoid, which account for 1% of all intracranial space-occupying lesions. Sellar/suprasellar ACs account for approximately 1% of all ACs. This is the first case of coexistence EPP with sellar/suprasellar AC. Case Report: A 67-year-old woman presented with 6 months history of fatigue. Her medical history was positive for irregular menstruation. Her endocrine examinations indicated low free thyroxine level with low TSH level, low oestradiol with low gonadotrophin level, slightly elevated prolactin level. Her Insulin-like growth factor-1 was below the normal levels. Dynamic contrast hypophysis MRI revealed a sellar cystic lesion with a dimension of 18 × 14 × 14 mm, extending from the suprasellar cistern, traversing the diaphragma sellae and reaching the level of the floor of the 3rd ventricle, consistent with sellar/suprasellar AC. There was no wall enhancement. The optic chiasm was compressed. The precontrast T1-weighted magnetic resonance images did not demonstrate the characteristic bright spot of posterior pituitary within the sella, which was higher in position, in the region of the median eminence. The pituitary stalk was not present. Conclusion: Although speculative, we have a hypothesis to explain how the EPP and sellar/- suprasellar AC coexist in this patient. Due to the absence of stalk, CSF may enter the sella tursica from the central aperture of the diaphragma sellae through which normally the stalk passes.

Surgery for diaphragma sellae meningioma: how I do it

Background Surgery for diaphragma sellae meningiomas (DSM) remains challenging due to the intimate neurovascular relationships of the tumor. Excision of DSM along with a decompression of the optic apparatus requires a good knowledge of the skull base anatomy and a precise preoperative evaluation of the tumor extensions. Method We describe the key steps of transcranial approach for DSM with a video illustration. The surgical anatomy is described along with the advantages and limitations of this approach. Conclusions The transcranial approach allows a safe tumor excision with an early and adequate control of the neurovascular structures, while minimizing postoperative CSF rhinorrhea.