Ultrasound-guided endoscopic endonasal resection of sellar and suprasellar craniopharyngiomas

Intra-Infundibular Epidermoid Cysts: A Distinct and Rare Entity

BACKGROUND

Epidermoid cysts located completely within the pituitary infundibulum are a rare entity with only 7 reported cases. In this study, we have described our experience with the resection of intra-infundibular epidermoid cysts (IECs) and reviewed the existing literature highlighting its distinguishing features and operative nuances.

METHODS

Three consecutive cases of IEC operated at our institute were retrospectively studied. PubMed and EMBASE databases were searched, and 7 case reports of IEC were found. Relevant clinical, radiological, and operative data of 10 cases were analyzed.

RESULTS

The median age at diagnosis was 53.5 years, and 6 cases were males. Preoperatively, although the average tumor size was only 1.62 cm3, 80% of patients had visual disturbance, and 78% of patients had a deficiency in pituitary hormones. Five patients had preoperative diabetes insipidus. Mild diffusion restriction was noted in 4 out of 5 cases that mentioned it. The most common differential diagnosis considered was Rathke's cleft cyst and craniopharyngioma. Adhesion of the cyst wall to the stalk and/or the hypothalamus was a common occurrence resulting in residual wall being left behind in 50% of cases. An expanded endoscopic endonasal approach was utilized in 9 cases, and 1 case underwent frontotemporal craniotomy with resection via pretemporal approach. Postoperative chemical meningitis was demonstrated in 2 cases, and a sterile abscess was noted in another case.

CONCLUSIONS

IECs are rare tumors that are often misdiagnosed preoperatively. They have different postoperative morbidity profiles compared to other cystic lesions in the infundibulum. This makes it important to recognize this distinct entity.

Use of intraoperative ultrasound in differentiating adamantinomatous versus papillary craniopharyngiomas and guiding resection through the endoscopic endonasal route

Craniopharyngiomas (CPs) are surgically challenging tumors. The prevalence of BRAF mutation in papillary craniopharyngioma (PCP) and the positive response with BRAF-MEK inhibitors have shifted the treatment paradigm towards targeted therapy. However, maximal safe resection remains the goal, particularly for adamantinomatous craniopharyngioma (ACP). In this report, we describe two cases of CP where intraoperative ultrasonography (IOUS) was helpful in differentiating the subtype of CP, thus enabling intraoperative decision-making regarding the extent of resection. Additionally, IOUS images of three more (two PCP and one ACP) patients who underwent endoscopic endonasal resection for CPs were retrospectively evaluated. Each of these entities showed characteristic appearances on IOUS.

Real-time intraoperative ultrasound imaging of the posterior pituitary gland during endoscopic endonasal approach

PURPOSE

Pituitary adenomas are amongst the most common benign central nervous system tumors, and often require resection via an endoscopic endonasal approach (EEA). Two of the most common associated complications are central diabetes insipidus (DI) and syndrome of inappropriate antidiuretic hormone secretion (SIADH). Both are thought to be caused by manipulation of the posterior pituitary gland (PPG), making intraoperative visualization and preservation of this structure critical. Intraoperative endoscopic endonasal ultrasound (IEUS) may present an optimal tool for this purpose. This study aims to describe the appearance and morphology of the PPG on IEUS.

METHODS

This study included all pituitary adenoma surgeries during which IEUS was utilized and the PPG was visualized between 1/1/2022, and 12/31/2023. Demographic, clinical, pathological, and radiological data were retrospectively collected. The PPG was described as either hypoechoic, isoechoic, or hyperechoic as compared to the anterior pituitary gland and adenoma, and the morphology of the PPG was further classified as ellipse or crescent shaped.

RESULTS

The PPG was hypoechoic in all 43 cases included in our final cohort (100.0%). Morphologically, the PPG appeared elliptical in 27 cases (62.8%), and crescent shaped in 16 cases (37.2%).

CONCLUSION

The PPG can typically be visualized by IEUS as a hypoechoic structure immediately anterior to the posterior wall of the sella turcica, with elliptical morphology being the most common appearance. These characteristics can be used by the skull base surgeon to more confidently identify the position and morphology of the PPG intraoperatively for its' preservation.

Long-term outcomes and potential predictive recurrence factors after endonasal endoscopic surgical treatment of symptomatic Rathke's cleft cysts

Although patients with symptomatic Rathke's cleft cysts (RCCs) receive surgical treatment, recurrence sometimes occurs after surgery. However, the mechanism underlying recurrence remains unclear. We evaluated the outcomes of RCC decompression over a long-term follow-up period. We retrospectively reviewed the medical records of 35 patients with symptomatic RCC who underwent endonasal endoscopic surgery (EES) at our institution between 2008 and 2023. Patients' characteristics, intraoperative findings, and postoperative follow-up outcomes were evaluated. A univariate regression model was used to identify the predictors of recurrence. The median patient age was 48.0 years, and 74.2% of the patients were female. The mean follow-up duration was 94.7 ± 47.6 months. Cyst content recurrence was observed in 15 patients (42.8%). Five patients (14.2%) with symptomatic recurrence underwent reoperation. Postoperative vision improved in all 23 patients (100%); headaches improved in 20 patients (90.9%). A new hormonal deficit occurred in two patients (5.7%). Complications included intraoperative cerebrospinal fluid (CSF) leak in 10 patients (28.5%), postoperative CSF leak in two patients (5.7%), permanent diabetes insipidus in two patients (5.7%), and postoperative infection in three patients (8.5%). Univariate analyses revealed that the position of the anterior pituitary lobe (p = 0.019) and preoperative visual disturbances (p = 0.008) significantly affected recurrence after surgery. Although EES was efficient, the recurrence rate was relatively high over a long-term period. The anterior pituitary lobe position and preoperative visual disturbances were significantly associated with recurrence. The anterior-inferior position can predict a high risk of recurrence before surgery.

Operative Adjuncts in Pediatric Brain Tumor Surgery with a Focus on Suprasellar Tumors

The primary objective of surgery for brain tumor resection has always been maximizing safe resection while minimizing the risk to normal brain tissue. Technological advances applied in the operating room help surgeons to achieve this objective. This chapter discusses specific tools and approaches in the operating environment that target safe surgery for brain tumors in children, with a focus on pathologies in the sellar/suprasellar region. Particular focus is given to tools that help with safe patient positioning; intraoperative imaging modalities; and chemical visualization adjuncts. Both static (preoperative images used for neuronavigation) and dynamic (images updated during the procedure) intraoperative imaging modalities are discussed. There is further overview of operative rehearsal and preparation strategies, which are rapidly evolving as virtual reality systems become more commonplace. While the rapid evolution of intraoperative adjuncts in neurosurgery means the status of a given technology as novel is quite transient, this chapter offers a snapshot of the current state of advanced intraoperative tools for pediatric brain tumor surgery.