Predictive factors of postoperative diabetes insipidus in 333 patients undergoing transsphenoidal surgery for non-functioning pituitary adenoma

Diabetes Insipidus after Endoscopic Endonasal Pituitary Macroadenoma Resection: Correlation of Patient and Surgery-Related Risk Factors

Purpose  This article aims to identify patient- and surgery-related factors that could predict the development of postoperative central diabetes insipidus (DI). Methods  This is a retrospective case-control study conducted at a single-institution tertiary referral center. Patients undergoing endoscopic endonasal skull base surgery for pituitary adenoma between November 2018 and April 2023 were recruited. The main outcome measures collected include age, gender, comorbidities, tumor type, postoperative DI, intraoperative and postoperative cerebrospinal fluid (CSF) leak, flow of CSF leak, number of layers required for repair, the use of nasal packing, and hospital length of stay. Results  A total of 20 patients developed DI postoperatively. Patients' demographic and comorbidity profile did not correlate with DI development. The encounter of an intraoperative CSF leak was correlated with postop DI (chi-square (1) = 18.35, p  < 0.001) with a relative risk (RR) of 2.7 (confidence interval [CI] = 1.37-5.28). The use of nasal packs was also correlated with postop DI (chi-square (1) = 10.17, p  = 0.001) with a RR of 1.8 (CI = 1.15-2.87). Defects requiring a two or more layers for reconstruction also correlated with postop DI compared to single layer repairs (chi-square (1) = 12.15, p  < 0.001) irrelevant of the materials used. Development of DI postop correlated with an increased hospital length of stay ( t (64) = -3.35, p  = 0.001). Conclusion  The physician should be careful when evaluating patients with pituitary adenomas in the postoperative period, particularly those with intraoperative CSF leak, nasal packing, and those who underwent multilayer reconstruction of the surgical defect.

Morphological Classification of Pituitary Tumors With Suprasellar Extension

BACKGROUND AND OBJECTIVES

The objective of this study was to study the association among various morphological parameters and surgical outcomes in pituitary macroadenomas with suprasellar extension.

METHODS

MRI studies of 160 patients undergoing endoscopic transsphenoidal resection of pituitary macroadenomas with suprasellar extension were reviewed. In the coronal plane, tumors were classified into Type 1 (dome-shaped, no constriction at the level of diaphragma sellae) and Type 2 (dumbbell-shaped, with constriction at the level of diaphragma sellae). Based on the dome-to-neck ratio (D/Nr), Type 2 tumors were further classified as Type 2A (wide neck; D/Nr >1 and <1.3) and Type 2B (narrow neck; D/Nr ≥1.3). Surgical outcomes and complications were analyzed using a logistic regression model. Overall extent of resection (EOR) and presence of residual sellar-suprasellar tumor was separately assessed in all patients with available postoperative MRI (n = 149).

RESULTS

There were 108 Type 1 tumors and 26 patients each in the Type 2A and Type 2B subgroups. Tumor subtype was significantly associated with tumor size (P < .001), intraoperative cerebrospinal fluid leak (P < .001), EOR (P < .001), postoperative suprasellar residual tumor (P < .001), and postoperative complications, including diabetes insipidus (P = .005) and visual worsening (P = .003). On multivariate analysis, after adjusting for confounders, Type 2B tumors were negatively associated with EOR (odds ratio [OR] 0.22; 95% CI 0.07-0.68; P = .008) and associated with the presence of postoperative suprasellar residual tumor (OR 18.08; 95% CI 5.20-62.89; P < .001), intraoperative cerebrospinal fluid leak (OR 5.33; 95% CI 1.89-14.99; P = .002), and postoperative diabetes insipidus (OR 4.89; 95% CI 1.67-14.35; P < .001).

CONCLUSION

Preoperative tumor classification based on D/Nr is clinically and surgically relevant, and Type 2B macroadenomas are significantly associated with lower rates of gross total resection and higher rates of postoperative complications after endoscopic transsphenoidal resection.

Arginine or Hypertonic Saline-Stimulated Copeptin to Diagnose AVP Deficiency

BACKGROUND

Distinguishing between arginine vasopressin (AVP) deficiency and primary polydipsia is challenging. Hypertonic saline-stimulated copeptin has been used to diagnose AVP deficiency with high accuracy but requires close sodium monitoring. Arginine-stimulated copeptin has shown similar diagnostic accuracy but with a simpler test protocol. However, data are lacking from a head-to-head comparison between arginine-stimulated copeptin and hypertonic saline-stimulated copeptin in the diagnosis of AVP deficiency.

METHODS

In this international, noninferiority trial, we assigned adult patients with polydipsia and hypotonic polyuria or a known diagnosis of AVP deficiency to undergo diagnostic evaluation with hypertonic-saline stimulation on one day and with arginine stimulation on another day. Two endocrinologists independently made the final diagnosis of AVP deficiency or primary polydipsia with use of clinical information, treatment response, and the hypertonic-saline test results. The primary outcome was the overall diagnostic accuracy according to prespecified copeptin cutoff values of 3.8 pmol per liter after 60 minutes for arginine and 4.9 pmol per liter once the sodium level was more than 149 mmol per liter for hypertonic saline.

RESULTS

Of the 158 patients who underwent the two tests, 69 (44%) received the diagnosis of AVP deficiency and 89 (56%) received the diagnosis of primary polydipsia. The diagnostic accuracy was 74.4% (95% confidence interval [CI], 67.0 to 80.6) for arginine-stimulated copeptin and 95.6% (95% CI, 91.1 to 97.8) for hypertonic saline-stimulated copeptin (estimated difference, -21.2 percentage points; 95% CI, -28.7 to -14.3). Adverse events were generally mild with the two tests. A total of 72% of the patients preferred testing with arginine as compared with hypertonic saline. Arginine-stimulated copeptin at a value of 3.0 pmol per liter or less led to a diagnosis of AVP deficiency with a specificity of 90.9% (95% CI, 81.7 to 95.7), whereas levels of more than 5.2 pmol per liter led to a diagnosis of primary polydipsia with a specificity of 91.4% (95% CI, 83.7 to 95.6).

CONCLUSIONS

Among adult patients with polyuria polydipsia syndrome, AVP deficiency was more accurately diagnosed with hypertonic saline-stimulated copeptin than with arginine-stimulated copeptin. (Funded by the Swiss National Science Foundation; CARGOx ClinicalTrials.gov number, NCT03572166.).

A Full View of Papillary Craniopharyngioma Based on Expanded Endonasal Approach: A Comprehensive Clinical Characterization of 101 Cases

OBJECTIVE

The enlarged endonasal approach (EEA) has emerged as the preferred surgical procedure for removing craniopharyngiomas, due to its advantages of direct visualization and reduction of blind corners. However, owing to a low incidence of papillary CPs (PCPs) compared to adamantinomatous CPs (ACPs), a full view of PCP based on the EEA approach is limited. In this paper, the authors present the largest series to date analyzing the clinical characteristics based on the EEA approach for PCPs.

METHODS

A retrospective review was conducted on 101 PCPs patients who underwent endoscopic endonasal surgery (EEA) and whose condition was confirmed via postoperative pathology. The PCPs were classified into three types based on MRI data and intraoperative findings from EEA: suprasellar/intra-suprasellar (3V floor intact) type (Type I), suprasellar/intra-suprasellar (3V floor invasive) type (Type II), and intra-third ventricle type (Type III). The general characteristics of the three types of tumors were summarized, and postoperative follow-up was conducted to record detailed information on changes in vision, endocrine replacement, tumor recurrence, and quality of life.

RESULTS

Out of the 101 cases, 36 (36.64%) were classified as type I, 52 (51.49%) as type II, and 13 (12.87%) as type III. The mean age of type III patients was 40.46 ± 14.15 years old, younger than the other two types (p = 0.021). Headache (84.62%) and memory decline (61.54%) were prominent features in patients with type III (p = 0.029). Visual impairment was more common in type II (80.77%, p = 0.01). Gross total resection (GTR) was achieved in 91 patients (90.10%). There were no significant differences in GTR rates among the three types of tumors. There were significant differences in quality of life among the three types of PCP (p = 0.004), and type III presented with the highest rate of good postoperative quality of life (92.31%) based on the KPS score. Thirteen (12.87%) tumors recurred within a mean follow-up time of 38 (range, 8-63) months. Type II PCPs (OR 5.826, 95%CI 1.185-28.652, p = 0.030) and relapsed patients (OR 4.485, 95%CI 1.229-16.374, p = 0.023) were confirmed as independent risk factors for tumor recurrence.

CONCLUSIONS

Most of the PCPs including intra-third ventricle PCPs can be safely and effectively removed through neuroendoscopy with EEA. Suprasellar/intra-suprasellar (third cerebral ventricle floor-invasive) type PCPs may have a worse postoperative quality of life compared to the other two types, and it may be a strong predictor of tumor recurrence.

Endoscopic Endonasal Transplanum-Transtuberculum Approach for Pituitary Adenomas/PitNET: 25 Years of Experience

The role of the endoscopic transplanum-transtuberculum approach (ETTA) in the treatment of pituitary adenomas/PitNETs (PAs) is sparsely analyzed in the literature, and its use is still debated in the current practice. The aim of this study was to report our experience with this approach. Our institutional registry was retrospectively reviewed, and patients who underwent ETTA for a PA from 1998 to 2022 were included. Fifty-seven cases were enrolled over a time span of 25 years, corresponding to 2.4% of our entire PA caseload. Radical resection was achieved in 57.9% of cases, with re-do surgery (p = 0.033) and vessel encasement/engulfment (p < 0.001) as predictors of partial resection. CSF leak incidence stood at 8.8%, with higher BMI (p = 0.038) as its only significant predictor. Partial or full improvement of the visual field deficits was achieved in 73.5% of cases. No surgical mortality was observed. According to our results, ETTA for the treatment of PAs is characterized by a satisfactory surgical outcome but with greater morbidity than the conventional endoscopic approach. Therefore, it should be reserved for the few selected cases otherwise unsuitable for the endoscopic trans-sphenoidal route, representing a valid alternative and an effective complementary route for the transcranial approach for these challenging PAs.

A Machine Learning-Based Prediction of Diabetes Insipidus in Patients Undergoing Endoscopic Transsphenoidal Surgery for Pituitary Adenoma

BACKGROUND

Diabetes insipidus (DI) is a common complication after endoscopic transsphenoidal surgery (TSS) for pituitary adenoma (PA), which affects the quality of life in patients. Therefore, there is a need to develop prediction models of postoperative DI specifically for patients who undergo endoscopic TSS. This study establishes and validates prediction models of DI after endoscopic TSS for patients with PA using machine learning algorithms.

METHODS

We retrospectively collected information about patients with PA who underwent endoscopic TSS in otorhinolaryngology and neurosurgery departments between January 2018 and December 2020. The patients were randomly split into a training set (70%) and a test set (30%). The 4 machine learning algorithms (logistic regression, random forest, support vector machine, and decision tree) were used to establish the prediction models. Area under the receiver operating characteristic curves were calculated to compare the performance of the models.

RESULTS

A total of 232 patients were included, and 78 patients (33.6%) developed transient DI after surgery. Data were randomly divided into a training set (n = 162) and a test set (n = 70) for development and validation of the model, respectively. The area under the receiver operating characteristic curve was highest in the random forest model (0.815) and lowest in the logistic regression model (0.601). Invasion of pituitary stalk was the most important feature for model performance, closely followed by macroadenomas, size classification of PA, tumor texture, and Hardy-Wilson suprasellar grade.

CONCLUSIONS

Machine learning algorithms identify preoperative features of importance and reliably predict DI after endoscopic TSS for patients with PA. Such a prediction model may enable clinicians to develop individualized treatment strategy and follow-up management.

Predictors of the Spontaneous Resolution of Central Diabetes Insipidus Following Endoscopic Endonasal Surgery for Craniopharyngioma

OBJECTIVE

Central diabetes insipidus (CDI) is the most common complication of endoscopic endonasal surgery (EES) for craniopharyngioma. However, some cases of CDI could spontaneously resolve during the follow-up period. Hence, this study aimed to determine the predictive factors for the spontaneous resolution of CDI.

METHODS

Data of patients with CDI who underwent EES for craniopharyngioma between February 2009 and June 2021 were retrospectively reviewed. All patients were divided into 2 groups based on the resolution of CDI during follow-up: the recovery and no recovery groups. The baseline characteristic, surgical, and follow-up results of patients were compared.

RESULTS

We identified 84 patients with CDI (35 in the recovery group and 49 in the no recovery group). A direct comparison showed that retaining the pituitary stalk (57.1% vs. 14.3%, P = 0.000) and no-hypothalamic injury (HI) (68.6% vs. 20.4%, P = 0.000) were more common in the recovery group, whereas hydrocephalus at diagnosis (8.6% vs. 46.9%, P = 0.000) was significantly more common in the no recovery group. Subsequently, we found through univariate and multivariate analysis that the spontaneous resolution of CDI was associated with hydrocephalus at diagnosis (yes vs. no: odds ratio [OR], 0.198; P = 0.045), pituitary stalk injury (retaining vs. sectioning: OR, 7.055; P = 0.004), and the Hong et al HI pattern (mild-HI vs. no-HI: OR, 0.183; P = 0.038; unilateral-HI vs. no-HI: OR, 0.147; P = 0.017; bilateral-HI vs. no-HI: OR, 0.154; P = 0.044).

CONCLUSIONS

Hydrocephalus at diagnosis, pituitary stalk injury, and the Hong et al HI pattern might be predictors of the spontaneous resolution of CDI following EES for craniopharyngioma.

Pituitary stalk changes on magnetic resonance imaging following pituitary adenoma resection using a transsphenoidal approach

Objective

We aimed to investigate the magnetic resonance imaging (MRI) findings and clinical significance of position and changes in morphology of the pituitary stalk following pituitary adenoma (PA) resection using a transsphenoidal approach.

Methods

We collected clinical and MRI data of 108 patients with PA after transsphenoidal surgery. Diameter, length, and coronal deviation of the pituitary stalk were measured pre-, post-, and mid-term post-operatively, to observe pituitary stalk morphology.

Results

Of 108 patients, 53 pituitary stalks were recognisable pre-operatively. The angle between the pituitary stalk and the median line was 7.22°-50.20° (average, 25.85°) in 22 patients with left-sided pituitary stalks and 5.32°-64.05° (average, 21.63°) in 20 patients with right-sided pituitary stalks. Of 42 patients with preoperative pituitary stalk deviation, 41 had an early postoperative recovery and 1 had increased deviation. In the mid-term postoperative period, 21 of 42 patients had pituitary stalks located centrally. In 53 patients, the pituitary stalk length was 1.41-11.74 mm (mean, 6.12 mm) pre-operatively, 3.61-11.63 mm (mean, 6.93 mm) in the early postoperative period, and 5.37-17.57 mm (mean, 8.83 mm) in the mid-term postoperative period. In the early postoperative period, 58 (53.70%) patients had posterior pituitary bright spots (PPBS) and 28 (25.92%) had diabetes insipidus (DI).

Conclusion

Pre-operatively, the pituitary stalk was compressed and thinned. Post-operatively, it could be stretched to a "normal state", and its position showed a gradual centring trend. Post-operatively, the length of the pituitary stalk gradually increased. The PPBS in the early postoperative period negatively correlated with postoperative DI.

New developments and concepts in the diagnosis and management of diabetes insipidus (AVP-deficiency and resistance)

Diabetes insipidus (DI) is a disorder characterised by the excretion of large amounts of hypotonic urine, with a prevalence of 1 per 25,000 population. Central DI (CDI), better now referred to as arginine vasopressin (AVP)-deficiency, is the most common form of DI resulting from deficiency of the hormone AVP from the pituitary. The less common nephrogenic DI (NDI) or AVP-resistance develops secondary to AVP resistance in the kidneys. The majority of causes of DI are acquired, with CDI developing when more than 80% of AVP-secreting neurons are damaged. Inherited/familial CDI causes account for approximately 1% of cases. Although the pathogenesis of NDI is unclear, more than 280 disease-causing mutations affecting the AVP2 protein or AVP V2 receptor, as well as in aquaporin 2 (AQP2), have been described. Although the cAMP/protein kinase A pathway remains the major regulatory pathway of AVP/AQP2 action, in vitro data have also revealed additional cAMP independent pathways of NDI pathogenesis. Diagnosing partial forms of DI, and distinguishing them from primary polydipsia, can be challenging, previously necessitating the use of the water deprivation test. However, measurements of circulating copeptin levels, especially after stimulation, are increasingly replacing the classical tests in clinical practice because of their ease of use and high sensitivity and specificity. The treatment of CDI relies on desmopressin administration, whereas NDI requires the management of any underlying diseases, removal of offending drugs and, in some cases, administration of diuretics. A better understanding of the pathophysiology of DI has led to novel evolving therapeutic agents that are under clinical trial.

Diagnosis and Management of Central Diabetes Insipidus in Adults

Central diabetes insipidus (CDI) is a clinical syndrome which results from loss or impaired function of vasopressinergic neurons in the hypothalamus/posterior pituitary, resulting in impaired synthesis and/or secretion of arginine vasopressin (AVP). AVP deficiency leads to the inability to concentrate urine and excessive renal water losses, resulting in a clinical syndrome of hypotonic polyuria with compensatory thirst. CDI is caused by diverse etiologies, although it typically develops due to neoplastic, traumatic, or autoimmune destruction of AVP-synthesizing/secreting neurons. This review focuses on the diagnosis and management of CDI, providing insights into the physiological disturbances underpinning the syndrome. Recent developments in diagnostic techniques, particularly the development of the copeptin assay, have improved accuracy and acceptability of the diagnostic approach to the hypotonic polyuria syndrome. We discuss the management of CDI with particular emphasis on management of fluid intake and pharmacological replacement of AVP. Specific clinical syndromes such as adipsic diabetes insipidus and diabetes insipidus in pregnancy as well as management of the perioperative patient with diabetes insipidus are also discussed.

Current Advances in the Management of Adult Craniopharyngiomas

Craniopharyngiomas (CPs) are slow growing, histologically benign intracranial tumors located in the sellar–suprasellar region. Although known to have low mortality, their location and relationship to the adjacent neural structures results in patients having significant neurologic, endocrine, and visual comorbidities. The invasive nature of this tumor makes complete resection a challenge and contributes to its recurrence. Additionally, these tumors are bimodally distributed, being treated with surgery, and are followed by other adjuncts, such as focused radiation therapy, e.g., Gamma knife. Advances in surgical techniques, imaging tools, and instrumentations have resulted in the evolution of surgery using endoscopic techniques, with residual components being treated by radiotherapy to target the residual tumor. Advances in molecular biology have elucidated the main pathways involved in tumor development and recurrence, but presently, no other treatments are offered to patients, besides surgery, radiation, and endocrine management, as the disease and tumor evolve. We review the contemporary management of these tumors, from the evolution of surgical treatments, utilizing standard open microscopic approaches to the more recent endoscopic surgery, and discuss the current recommendations for care of these patients. We discuss the developments in radiation therapy, such as radiosurgery, being used as treatment strategies for craniopharyngioma, highlighting their beneficial effects on tumor resections while decreasing the rates of adverse outcomes. We also outline the recent chemotherapy modalities, which help control tumor growth, and the immune landscape on craniopharyngiomas that allow the development of novel immunotherapies.