Role of Copeptin in Predicting Postoperative Hyponatremia and Hypernatremia in Patients Undergoing Endoscopic Pituitary Adenoma Surgery.

BACKGROUND AND OBJECTIVES: Arginine vasopressin (AVP) is an important hormone responsible for maintaining sodium homeostasis after pituitary surgery. The measurement of AVP levels is difficult because of its short half-life (t1/2). Copeptin is a preprohormone of AVP, and it is a more stable peptide, which can be used as surrogate marker for AVP. This study aims to assess the role of copeptin as a predictor of postoperative hyponatremia and hypernatremia in patients undergoing endoscopic pituitary adenoma surgery. METHODS: This prospective study included 50 patients who underwent endoscopic pituitary adenoma surgery. Serum copeptin levels of these patients were assessed (1) preoperatively (C1), (2) at extubation (C2), and (3) postoperative day 4 (C3). Perioperative data regarding fluid and sodium balance were collected from patients. Statistical analysis was done using the above data. RESULTS: The copeptin values were assessed against the sodium disturbances. 100% of patients who developed transient diabetes insipidus had a relative decrease in C2 from C1 (P - .0002). 88% of patients who developed early hyponatremia had a relative increase in C2 as compared with C1 (P < .01). 75% of patients who developed delayed hyponatremia had a relative increase in C3 as compared with C1 (P = .003). CONCLUSION: A relative increase or decrease in early change in copeptin (C2-C1) can predict development of early hyponatremia or transient central diabetes insipidus, respectively. A relative increase in delayed change in copeptin (C3-C1) can predict development of delayed hyponatremia.

Large Pituitary Adenoma: Strategies to Maximize Volumetric Resection Using Endoscopic Endonasal Approaches and an Analysis of Factors Limiting Resection.

BACKGROUND: Large pituitary adenomas (LPAs), which constitute ∼5%-14% of all pituitary adenomas, are considered challenging tumors owing to their locally aggressive behavior, low gross total resection rate, and high prevalence of visual deficits and hypopituitarism. We evaluated the utility of various extended endoscopic endonasal approaches in maximizing the resection of LPAs and studied the factors affecting the extent of surgical resection. METHODS: A retrospective study of all LPAs (defined as a minimum diameter >3 cm and tumor volume >10 cm3) treated via an endoscopic endonasal approach between January 2015 and December 2020 was performed. The volumetric extent of resection (3-dimensional volumetric analysis software) was correlated with various demographic, tumor-related, pathologic, and immunohistochemical factors and its effects on the clinical outcomes studied. RESULTS: The present study included 106 patients with LPAs. The mean extent of the resection volume was 79.18 ± 21.75 cm3. The factors that affected the extent of resection included the preoperative tumor volume (P = 0.03) and Knosp grade (P = 0.03). The percentage increase in the extent of resection with the use of 2 endonasal corridors was 10.6% and with 3 corridors was 14%. Visual improvement occurred in 82% of patients, and new-onset persistent hormonal insufficiency occurred in 2.9% of patients. Mortality directly related to surgery occurred in 1.8% of cases. CONCLUSIONS: Extended endoscopic endonasal approaches can safely and effectively be used for gross total resection of LPAs. However, we found that the preoperative tumor volume and Knosp grade were significant factors affecting the extent of tumor resection. The use of multiple endoscopic endonasal corridors can increase the volumetric extent of resection for LPAs.

Endoscopic Endonasal Excision of a Meckel's Cave Dermoid Cyst.

Background: Meckel's cave dermoid cyst is an extremely rare and a technically challenging lesion. The objective of the study is to show that endoscopic endonasal approach (EEA) has recently emerged as a better alternative to transcranial approach for this formidable tumor, owing to minimal retraction-related morbidity. Method: A 52-year-old male presented with numbness over the right side of the face and temporal area for the last 3 years. On examination, there was decreased sensation to touch, pain, and temperature over the right V1, V2, and V3 areas with an absent right corneal reflex. Imaging revealed a heterogenous extra-axial lesion in the right Meckel's cave. The tumor was resected by an extended endonasal transpterygoid approach. Results: The patient had improvement in his symptoms with no endocrine complication. Conclusion: This case demonstrates the surgical techniquenof endoscopic endonasal transpterygoid resection of a Meckel's cave dermoid cyst.

Endoscopic Endonasal Excision of a Complex Craniopharyngioma Operated Multiple Times by Transcranial Route.

Background: Complex craniopharyngiomas pose a significant surgical challenge owing to its proximity to critical structures and its intrinsic nature to resist radical excision. Objective: To show that endoscopic endonasal approach (EEA) is potentially a better alternative to transcranial approach in tumors that have been operated multiple times by transcranial route for achieving radical excision with minimal morbidity. Materials and Methods: A 32-year-old male previously operated twice through interhemispheric approach for craniopharyngioma presented with blurring of vision accompanied by headache and intermittent diplopia. Imaging revealed a large lobulated suprasellar recurrence with a large calcified part adjacent to left internal carotid artery. The tumor was resected by an extended endonasal approach. The patient experienced improvement in his vision with no significant endocrine complication. Results and Conclusion: This case demonstrates the surgical technique and various operative nuances of endoscopic endonasal resection of a complex craniopharyngioma.