The predictive value of intraoperative visual evoked potential for visual outcome after extended endoscopic endonasal surgery for adult craniopharyngioma

Pediatric craniopharyngioma with significantly increased intraoperative visual evoked potential amplitude and postoperative visual acuity improvement: a case report

Visual evoked potential (VEP) is an established modality that allows safe brain tumor resection and preservation of optical function. We herein present a case of a pediatric craniopharyngioma with significant improvement in the VEP amplitude detected during endoscopic transsphenoidal surgery (ETS) and obvious postoperative improvement in visual acuity. A 13-year-old boy presented with visual acuity disturbance in his right eye and was followed up for 5 months by an ophthalmologist. His visual acuity rapidly worsened, and a suprasellar lesion with calcification was found on brain computed tomography. The patient underwent tumor resection during ETS with intraoperative transcranial VEP monitoring. Gross total tumor resection was achieved without injury to the perforators, including the superior hypophyseal arteries. The VEP amplitude was unstable, and significant waves were not detectable before tumor resection; however, a positive wave was detected after removing most of the tumor and exposing the bilateral optic nerves and optic chiasm. Subsequently, negative and positive VEP waves were continuously detected. Visual acuity improved remarkably on postoperative day 10. This case demonstrated both a significant increase in the intraoperative VEP amplitude and rapid postoperative improvement in visual acuity. We surmised that the preoperative rapid worsening of visual dysfunction, intraoperative increase in the VEP amplitude, and significant postoperative improvement in visual acuity were associated with the compression of the optic nerves by the internal carotid artery, anterior cerebral artery, and tumor.

Endoscopic endonasal transsphenoidal approach improves endocrine function and surgical outcome in primary craniopharyngioma resection: a systematic review and meta-analysis

BACKGROUND

Craniopharyngiomas (CPs) are generally derived from the craniopharyngeal duct epithelium, accounting for 38% and 24.5% of mortality in pediatric and adult patients, respectively. At present, the widespread application of the endoscopic endonasal transsphenoidal approach (EEA) has led to controversy between the traditional microscopic transcranial approach (TCA) and EEA in relation to the surgical management of CPs.

OBJECT AND METHOD

We performed a systematic review and meta-analysis comparing the complications, surgical outcomes, and endocrine functions of patients with CPs to provide evidence-based decision-making in their surgical management.

RESULT

Overall, 11 observational studies with 12,212 participants were included in the meta-analysis, in which five of them only included an adult population, three of them only included a child population, and the other three studies included a mixed population (adult and child). In pediatric patients, the EEA achieved a higher gross total resection (GTR) rate (odds ratio (OR) = 5.25, 95%CI: 1.21-22.74), lower recurrence rate (OR = 0.54, 95%CI: 0.31-0.94, p = 0.030), and less hypopituitarism (OR = 0.34, 95%CI: 0.12-0.97, p = 0.043). In adult patients, EEA significantly improved mortality (OR = 0.09, 95%CI: 0.06-0.15, p < 0.001) and visual outcomes (visual improvement: OR = 3.42, 95%CI: 1.24-9.40, p = 0.017; visual deficit: OR = 0.30, 95%CI: 0.26-0.35) with decreases in postoperative stroke (OR = 0.58, 95%CI: 0.51-0.66, p < 0.001), hydrocephalus, and infections (OR = 0.32, 95%CI: 0.24-0.42, p < 0.001).

CONCLUSION

Compared with the traditional TCA in primary CP resection, the development and wide application of EEA optimistically decreased the recurrence rate of CP, alleviated hypopituitarism with improvement in the GTR rate of pediatric patients, and significantly improved the visual outcomes, hydrocephalus, postoperative stroke, survival, and infection rates of the patients. Therefore, EEA is an optimal approach for primary CP resection.

Advances in the treatment of Adamantinomatous craniopharyngioma: How to balance tumor control and quality of life in the current environment: a narrative review

Adamantinomatous craniopharyngioma (ACP) presents a significant challenge to neurosurgeons despite its benign histology due to its aggressive behavior and unique growth patterns. This narrative review explores the evolving landscape of ACP treatments and their efficacy, highlighting the continuous development in therapeutic approaches in recent years. Traditionally, complete resection was the primary treatment for ACP, but surgical -related morbidity have led to a shift. The invasive nature of the finger-like protrusions in the histological structure results in a higher recurrence rate for ACP compared to papillary craniopharyngioma (PCP), even after complete macroscopic resection. Given this, combining subtotal resection with adjuvant radiotherapy has shown potential for achieving similar tumor control rates and potentially positive endocrine effects. Simultaneously, adjuvant treatments (such as radiotherapy, intracystic treatment, and catheter implantation) following limited surgery offer alternative approaches for sustained disease control while minimizing morbidity and alleviating clinical symptoms. Additionally, advances in understanding the molecular pathways of ACP have paved the way for targeted drugs, showing promise for therapy. There is a diversity of treatment models for ACP, and determining the optimal approach remains a subject of ongoing debate in the present context. In order to achieve a good-term quality of life (QOL), the main goal of the cyst disappearance or reduction of surgical treatment is still the main. Additionally, there should be a greater emphasis on personalized treatment at this particular stage and the consideration of ACP as a potentially chronic neurosurgical condition. This review navigates the evolving landscape of ACP therapies, fostering ongoing discussions in this complex field.

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.

Clinical Significance of Plasma Leptin and Its Receptors mRNA Expression in Craniopharyngiomas: A Prospective Study

Craniopharyngioma (CP) is a benign tumor with a high rate of obesity and frequent recurrence. Moreover, the role of leptin/leptin receptors axis in obesity and the prognosis of CP is still unknown. Plasma leptin concentration and mRNA expression of leptin receptors were assessed in patients with CP. Moreover, the association between leptin/leptin receptors axis, weight-related outcomes, and progression-free survival (PFS) were explored in CP patients. Leptin receptors overexpressed in CP tumor tissue were compared to normal brain tissue (p < 0.05); compared to healthy controls, the concentration of leptin was elevated in CP with or without matched age, sex, and body mass index (BMI) (p < 0.05). The high plasma leptin level was an independent risk predictor for significant weight gain (adjusted odds ratio (aOR) = 2.29, and p = 0.030) and new-onset obesity (aOR = 6.64, and p = 0.016). High plasma leptin level (adjusted hazard ratio (aHR) = 3.74, and p = 0.011) and leptin receptor (LEPR) mRNA expression (aHR = 3.12, and p = 0.045) were independent risk factors for poor PFS in CP. Inappropriately elevated leptin relative to BMI and its failure to inhibit further weight gain indicate the existence of leptin resistance in patients with CP. Leptin and LEPR were independent predictors for PFS of patients with CP. The leptin/leptin receptors axis may be a potential therapeutic target for obesity in patients with CP.

Effects of Craniotomy and Endoscopic Endonasal Transsphenoidal Surgery on Bodyweight in Adult-Onset Craniopharyngioma: A Single-Center Retrospective Study

Craniopharyngioma (CP) is a histologically benign tumor with high mortality and morbidity. Although surgical treatment is essential in managing CP, the best surgical approach is debated. A retrospective cohort of 117 patients with adult-onset CP (AOCP) treated between 2018 and 2020 in Beijing Tiantan Hospital was identified and examined. The effects of traditional craniotomy (TC) and endoscopic endonasal transsphenoidal surgery (EETS) on the extent of surgical resection, hypothalamic involvement (HI), postoperative endocrine function, and postoperative weight were compared in the cohort. The cohort comprised 43 males and 74 females, divided into the TC (n = 59) and EETS (n = 58) groups. The EETS group possessed a higher rate of gross total resection (GTR) (adjusted odds ratio (aOR) = 4.08, p = 0.029) and improved HI (aOR = 2.58, p = 0.041) than the TC group. Worse postoperative HI was only observed in the TC group (5 patients). The EETS was associated with fewer adverse hormonal outcomes, including posterior pituitary dysfunction (aOR = 0.386, p = 0.040) and hypopituitarism (aOR = 0.384, p = 0.031). Additionally, multivariate logistic regression analysis confirmed that EETS was related to fewer cases of weight gain >5% (aOR = 0.376, p = 0.034), significant weight change (aOR = 0.379, p = 0.022), and postoperative obesity (aOR = 0.259, p = 0.032). Compared to TC, EETS shows advantages in accomplishing GTR, hypothalamus protection, postoperative endocrine function reservation, and postoperative weight control. These data suggest that the EETS deserves more application in managing patients with AOCP.

Evolution of flash visual evoked potentials to monitor visual pathway integrity during tumor resection: illustrative cases and literature review

Flash visual evoked potentials (fVEPs) provide a means to interrogate visual system functioning intraoperatively during tumor resection in which the optic pathway is at risk for injury. Due to technical limitations, fVEPs have remained underutilized in the armamentarium of intraoperative neurophysiological monitoring (IONM) techniques. Here we review the evolution of fVEPs as an IONM technique with emphasis on the enabling technological and intraoperative improvements. A combined approach with electroretinography (ERG) has enhanced feasibility of fVEP neuromonitoring as a practical application to increase safety and reduce error during tumor resection near the prechiasmal optic pathway. The major advance has been towards differentiating true cases of damage from false findings. We use two illustrative neurosurgical cases in which fVEPs were monitored with and without ERG to discuss limitations and demonstrate how ERG data can clarify false-positive findings in the operating room. Standardization measures have focused on uniformity of photostimulation parameters for fVEP recordings between neurosurgical groups.

Comparison of the effect of sedation and general anesthesia on pattern and flash visual evoked potentials in normal dogs

Background

Visual evoked potentials (VEPs) can provide objective functional assessment of the post-retinal visual pathway. This study compared the effects of sedation (butorphanol and dexmedetomidine) and general anesthesia (propofol and sevoflurane) on pattern and flash VEPs. Dogs (n = 13) underwent sedation or anesthesia and VEPs were obtained from 3 subcutaneous recording electrodes placed on the head (O1, Oz, O2).

Results

Pattern VEPs could only be recorded under sedation and a maximum of 3 peaks were identified (N75, P100, N135). Flash VEPs could be recorded under both sedation and anesthesia and a maximum of 5 peaks were identified (N1, P1, N2, P2, N3). The latency of the N1 peak and the baseline-N1 amplitude were significantly longer under general anesthesia.

Conclusion

Visual evoked potentials should be preferentially recorded in dogs sedated with dexmedetomidine and butorphanol, regardless of the stimulus.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03375-5.

Feasibility of endoscopic endonasal resection of intrinsic third ventricular craniopharyngioma in adults

Intrinsic third ventricular craniopharyngiomas (IVCs) are usually considered as a contraindication of endoscopic endonasal approach (EEA). The aim of this study is to evaluate the safety and feasibility of EEA for the resection of IVCs based on MRI topographical diagnosis and surgical findings. We reviewed the data of 22 patients who were diagnosed to be IVCs according to five MRI criteria and underwent surgery through EEA. Sixteen IVCs were resected using endoscopic endonasal infrachiasmatic corridor, five IVCs by using endoscopic endonasal suprachiasmatic trans-lamina terminalis corridor, and one IVC by using both the infrachiasmatic and suprachiasmatic corridors. During the operation, all the 22 cases were verified to be IVCs. Gross total resection was achieved in 21 (95.5%) patients. After surgery, visual improvement was observed in 14 (63.6%) patients, no change in 6 (27.3%) patients, and some deterioration in 2 (9.1%) patients. An improvement in intellectual ability was observed in nine (40.9%) patients, no change in twelve (54.5%) patients, and some deterioration in one (4.5%) patient. Fifteen of the 22 patients (68.2%) developed new endocrinological deficit. One postoperative cerebral spinal fluid leakage occurred. EEA can be used as a safe and efficacious approach for the radical resection of IVCs. The combination of the five MRI criteria may serve as an accurate preoperative diagnostic tool to define the topographical relationships between craniopharyngiomas and the third ventricle. The endoscopic transnasal view from below has the advantage of clarifying the relationship between tumors and the third ventricle floor.

Clinical Outcomes of Transcranial and Endoscopic Endonasal Surgery for Craniopharyngiomas: A Single-Institution Experience

OBJECTIVE

Craniopharyngioma has always been a challenge for the neurosurgeon, and there is no consensus on optimal treatment. The objective of this study was to compare surgical outcomes and complications between transcranial surgery (TCS) and endoscopic endonasal surgery (EES) of craniopharyngiomas.

METHODS

A retrospective review of patients who underwent craniopharyngioma resection at Wuhan Union Hospital between January 2010 and December 2019 was performed. A total of 273 patients were enrolled in this retrospective study. All patients were analyzed with surgical effects, endocrinologic outcomes, complications, and follow-up results.

RESULTS

A total of 185 patients underwent TCS and 88 underwent EES. There were no significant differences in patient demographic data, preoperative symptoms, and tumor characteristics between the two groups. The mean follow-up was 30.5 months (range 8-51 months). The EES group had a greater gross total resection (GTR) rate (89.8% EES vs. 77.3% TCS, p < 0.05) and lower rate of hypopituitarism (53.4% EES vs. 68.1% TCS, p < 0.05) and diabetes insipidus (DI) (51.1% EES vs. 72.4% TCS, p < 0.05). More postoperative cerebrospinal fluid (CSF) leaks occurred in the EES group (4.5% EES vs. 0% TCS, p < 0.05). More patients in the EES group with preoperative visual deficits experienced improvement after surgery (74.5% EES vs. 56.3% TCS, p < 0.05). There were statistical differences in the recurrence rates (12.5% EES vs. 23.8% TCS, p < 0.05) between the 2 groups.

CONCLUSION

These data support the view that EES is a safe and effective minimally invasive surgery compared to TCS. Compared to TCS, EES has fewer surgical complications and a lower recurrence rate.

Prognostic Utility of Optical Coherence Tomography for Visual Outcome After Extended Endoscopic Endonasal Surgery for Adult Craniopharyngiomas

INTRODUCTION

Owing to the close vicinity of the optic chiasma, visual dysfunction is known as one of the most common surgical indications and postoperative complications in adult patients with craniopharyngiomas, probably leading to poor quality of life. Historically, very few consistent predictive factors associated with the visual outcome are identified, which may not be helpful for patient counseling and preoperative decision making. Recently, optical coherence tomography (OCT) serving as a novel high-resolution imaging technique can assess the retinal morphology by measuring the circumpapillary retinal nerve fiber layer (cpRNFL) and macular ganglion cell complex thickness. However, few studies have examined the prognostic utility of OCT parameters for visual outcome after surgery for craniopharyngiomas. This study aims to use the largest series to evaluate the association between OCT parameters and visual outcome after extended endoscopic endonasal surgery (EEES) for primary craniopharyngiomas in adults.

MATERIAL AND METHODS

From October 2018 to October 2020, one hundred and seventy eyes in 88 adult patients with newly confirmed craniopharyngiomas were retrospectively reviewed and pertinent prognostic factors were analyzed.

RESULTS

Gross total resection was performed in 82 (93.2%) patients. The median postoperative follow-up time was 10.9 months. Multiple logistic regression analysis showed that increased temporal cpRNFL thickness was associated with higher odds of visual acuity (VA) improvement and maintenance (OR = 1.070; 95% CI, 1.005-1.140; p = 0.035), and greater inferior cpRNFL thickness was significantly associated with visual field (VF) improvement and maintenance (OR = 1.034; 95% CI, 1.001-1.068; p = 0.046). Furthermore, tight adhesion between optic nerves and craniopharyngiomas was demonstrated as an independent adverse factor for either postoperative VA or VF (p = 0.048, p = 0.030, respectively). The ROC results further verified the robustness of the prediction model either in VA (AUC = 0.843; 95% CI, 0.734-0.952; p < 0.001) or VF (AUC = 0.849; 95% CI, 0.741-0.958; p < 0.001).

CONCLUSION

Preoperative OCT can effectively predict visual outcome after EEES for adult craniopharyngiomas. It can also serve as a reliable alternative to evaluate preoperative visual field defects, especially for patients with lower compliance. Tight adhesion was confirmed as an independent risk factor for postoperative visual outcome. The OCT-based multivariable prediction models developed in the present study may contribute to patient counseling on visual prognosis.

Expanded Transsphenoidal Trans-Lamina Terminalis Approach to Tumors Extending Into the Third Ventricle: Technique Notes and a Single Institute Experience

Object

The trans lamina terminalis approach (TLTA) has been described as a way to remove third ventricular tumors. The aim of this paper was to analyze the feasible outcomes of TLTA applied to tumors extending into the third ventricle in our institute.

Methods

Suprasellar tumors (n = 149) were treated by the extended endonasal approach from September 2019 to December 2020 in Beijing Tiantan Hospital. Eleven of the tumors were treated by TLTA or TLTA via the trans-chiasm-pituitary corridor (TCPC). The surgical technique notes of TLTA were described and indications and outcomes of the approach were analyzed.

Results

There were 11 patients enrolled in the study, six with papillary craniopharyngiomas, two with adamantinomatous craniopharyngiomas, one with a germinal cell tumor (GCT), one with cavernous malformation and one with chordoid glioma. Four of the patients received a radical resection by TLTA alone, while seven of them received TLTA via the TCPC. Gross total resection was achieved in eight patients (72.7%), and partial resection in three patients (27.3%). Visual function was improved in four of the 11 patients (36.4%), was unchanged in five patients (45.5%), and deteriorated in two patients (18.2%). New-onset hypopituitarism occurred in seven patients (63.3%) and new-onset diabetes insipidus occurred in two patients (18.2%). Electrocyte imbalance were observed in six patients (54.5%) at post-operative week 2. There were no surgery-related deaths or cerebrospinal fluid leaks. Postoperative intracranial infection was observed in one patient (9.1%), and during the follow-up period, tumor recurrence occurred in one patient (9.1%).

Conclusion

The expanded TLTA provides a feasible suprachiasm corridor to remove tumors extending into the third ventricle, especially for craniopharyngiomas. Sound understanding of the major strengths and limitations of this approach, as well as strategies for complication avoidance, is necessary for its safe and effective application.

Prediction of Post-operative Visual Deterioration Using Visual-Evoked Potential Latency in Extended Endoscopic Endonasal Resection of Craniopharyngiomas

Background: The current study aimed to investigate the predictive value of visual-evoked potential (VEP) latency for post-operative visual deterioration in patients undergoing craniopharyngioma resection via extended endoscopic endonasal approach (EEEA).

Methods: Data from 90 patients who underwent craniopharyngioma resection via EEEA with intraoperative VEP monitoring were retrospectively reviewed. P100 latency was compared between patients with and without post-operative visual deterioration, and the threshold value of P100 latency for predicting post-operative visual deterioration was calculated by the receiver operating characteristic curve analysis. In addition, other potential prognostic factors regarding post-operative visual outcomes were also analyzed by multivariate analysis.

Results: Patients with post-operative visual deterioration showed a significantly longer VEP latency than those without (p < 0.001). An extension over 8.61% in VEP latency was identified as a predictor of post-operative visual deterioration (p < 0.001). By contrast, longer preoperative visual impairment duration and larger tumor volume were not significant predictors for post-operative visual deterioration.

Conclusions: The current study revealed that intraoperative VEP monitoring in EEEA is effective for predicting post-operative visual deterioration, and an extension over 8.61% in VEP latency can be used as a critical cut-off value to predict post-operative visual deterioration.

Intraoperative monitoring of visual evoked potentials in patients undergoing transsphenoidal surgery for pituitary adenoma: a systematic review

BACKGROUND

Transsphenoidal surgery is the gold standard for pituitary adenoma resection. Although rare, a serious complication of surgery is worsened vision post-operatively.

OBJECTIVE

To determine whether, in patients undergoing transsphenoidal surgery for pituitary adenoma, intraoperative monitoring of visual evoked potentials (VEP) is a safe, reproducible, and effective technological adjunct in predicting postoperative visual function.

METHODS

The PubMed and OVID platforms were searched between January 1993 and December 2020 to identify publications that (1) featured patients undergoing transsphenoidal surgery for pituitary adenoma, (2) used intraoperative optic nerve monitoring with VEP and (3) reported on safety or effectiveness. Reference lists were cross-checked and expert opinion sought to identify further publications.

RESULTS

Eleven studies were included comprising ten case series and one prospective cohort study. All employed techniques to improve reliability. No safety issues were reported. The only comparative study included described a statistically significant improvement in post-operative visual field testing when VEP monitoring was used. The remaining case-series varied in conclusion. In nine studies, surgical manipulation was halted in the event of a VEP amplitude decrease suggesting a widespread consensus that this is a warning sign of injury to the anterior optic apparatus.

CONCLUSIONS

Despite limited and low-quality published evidence regarding intra-operative VEP monitoring, our review suggests that it is a safe, reproducible, and increasingly effective technique of predicting postoperative visual deficits. Further studies specific to transsphenoidal surgery are required to determine its utility in protecting visual function in the resection of complex pituitary tumours.