Original ArticleIs Low-Lying Optic Chiasm an Obstacle to an Endoscopic Endonasal Approach for Retrochiasmatic Craniopharyngiomas? (Korean Society of Endoscopic Neurosurgery -003)
Introduction
Craniopharyngioma (CP) is a rare benign tumor of the sellar and parasellar regions. It accounts for 1%–4% of all primary intracranial tumors and has a bimodal age distribution pattern that epidemiologically peaks in children and adults.1, 2, 3, 4 CP rarely undergoes malignant progression, and complete resection of the tumor may be curative.5 When incompletely resected, CP shows a high recurrence rate despite its benign histologic feature.6 Although CP should be treated using combined therapy, surgical removal of the tumor remains the first line of therapy, with a considerable probability of cure.7 However, complete resection is challenging because CP is close to critical structures such as the optic apparatus, pituitary stalk, hypothalamus, and internal carotid artery.8, 9, 10, 11
Recently, endoscopic endonasal surgery for CP has shown a remarkable progress and proved to be safe and effective.8, 12, 13 The endoscopic endonasal approach (EEA) showed successful resection rates compared with conventional transcranial surgeries.14 The advantages of the EEA are accessing the tumor immediately after dural opening and enabling a direct visualization of the surgical plane without brain retraction.13 Despite the advances in endoscopic techniques, CP with a retrochiasmatic-growing pattern remains challenging to completely remove through the EEA, because the low-lying optic chiasm sometimes results in a narrow surgical corridor and blocks the pathway to the tumor.15, 16 In contrast, upward displacement of the optic chiasm by the tumor can provide a wider surgical corridor for the EEA. Therefore, evaluating the topographic relationship between the optic chiasm and the tumor is of major concern for the EEA.10, 11, 17, 18, 19, 20
In this study, we focused on whether the displacement of the optic chiasm affects the clinical results of the EEA for CP. The study aimed to identify the endoscopic surgical outcomes of retrochiasmatic CP and resolve the issues related to the position of the chiasm.
Section snippets
Methods
We retrospectively analyzed 154 consecutive patients with CP who underwent endoscopic endonasal surgery at 2 independent institutions (Seoul National University of Hospital, Seoul, Korea and Samsung Medical Center, Seoul, Korea) from February 2009 to April 2017. An endoscopic skull base team consisting of neurosurgeons (D.K. and D.N.) and an otolaryngologist (S.H.) from Samsung Medical Center and 1 neurosurgeon (Y.K.) from Seoul National University Hospital performed the EEA. Of 154 patients,
Patient Characteristics
Retrochiasmatic CPs were found in 142 of 154 patients (92.2%) initially reviewed (Table 1). The median age of patients at surgery was 43 years (range, 13–75 years), with 10 children and 132 adults. There were 74 male and 68 female patients. The median follow-up time was 25 months (range, 1–98 months). Of the 142 procedures, 101 (71.1%) were the first operation for primary CPs, whereas 41 (28.9%) were operations for recurrent tumors. The median maximal diameter was 2.5 cm (range, 1.0–7.3 cm).
Tumor Control Rates and Related Factor
The rates of GTR after the EEA vary widely, and 66.9% of GTR was reported in a meta-analysis.3 The rate of successful resection decreases substantially for recurrent CPs.3, 11 Regarding the prognostic factors for successful resection, preoperative factors did not affect the rate of successful resection except for treating recurrent tumors. Because total resection of recurrent CP remains a challenge even in experienced hands, the maximal safe tumor resection at the first surgery should be
Conclusions
The low-lying chiasm can interfere with surgical working space during EEA for retrochiasmatic CP. It is frequently found in recurrent tumors or those originating from the infundibulum to the third ventricular chamber. However, EEA is affordable to obtain successful outcomes even in the presence of low-lying chiasm. The experienced surgical techniques could overcome the narrow surgical corridor caused by the low-lying chiasm.
References (36)
- et al.
Endoscopic endonasal compared with microscopic transsphenoidal and open transcranial resection of craniopharyngiomas
World Neurosurg
(2012) - et al.
Association of pituitary stalk management with endocrine outcomes and recurrence in microsurgery of craniopharyngiomas: a meta-analysis
Clin Neurol Neurosurg
(2015) - et al.
Growth patterns of craniopharyngioma in children: role of the diaphragm sellae and its surgical implication
Surg Neurol
(2002) - et al.
Nasoseptal flap elevation in patients with history of septal surgery: does it increase flap failure or cerebrospinal fluid leakage?
World Neurosurg
(2016) - et al.
Clinical outcome after extended endoscopic endonasal resection of craniopharyngiomas: two-institution experience
World Neurosurg
(2017) - et al.
Predictive factors for craniopharyngioma recurrence: a systematic review and illustrative case report of a rapid recurrence
World Neurosurg
(2013) - et al.
The descriptive epidemiology of craniopharyngioma
J Neurosurg
(1998) - et al.
Craniopharyngioma
Pituitary
(2006) - et al.
Pathological and topographical classification of craniopharyngiomas: a literature review
J Neurol Surg Rep
(2016) - et al.
Surgical treatment of craniopharyngiomas: experience with 168 patients
J Neurosurg
(1999)
Craniopharyngioma: a comparison of tumor control with various treatment strategies
Neurosurg Focus
Expanded endonasal approach, a fully endoscopic transnasal approach for the resection of midline suprasellar craniopharyngiomas: a new classification based on the infundibulum
J Neurosurg
The endoscopic endonasal approach for the management of craniopharyngiomas involving the third ventricle
Neurosurg Rev
Growth patterns of craniopharyngiomas: clinical analysis of 226 patients
J Neurosurg Pediatr
Craniopharyngioma recurrence: the impact of tumor topography
J Neurosurg
The evolution of the endonasal approach for craniopharyngiomas
J Neurosurg
The role of the endoscopic endonasal route in the management of craniopharyngiomas
World Neurosurg
Endoscopic endonasal surgery for craniopharyngiomas: surgical outcome in 64 patients
J Neurosurg
Cited by (11)
Recurrence Rate and Prognostic Factors for the Adult Craniopharyngiomas in Long-Term Follow-Up
2020, World NeurosurgeryCitation Excerpt :The necessity of various transcranial techniques for craniopharyngiomas is fundamentally caused by an inborn defect of the optical features of microscopes, which provide the only straight view in the relatively narrow viewing angle in contrast to human eyes or endoscopes. The introduction of ESS in the 2000s expanded the indications of TSA in craniopharyngiomas with advances in surgical techniques and anatomical understanding.29,30 Therefore, the follow-up period of studies on ESS of craniopharyngiomas was much shorter that of those on TCA.
Clinical Efficacy of Optical Coherence Tomography to Predict the Visual Outcome After Endoscopic Endonasal Surgery for Suprasellar Tumors
2019, World NeurosurgeryCitation Excerpt :All surgeries were performed in a single tertiary institution (Samsung Medical Center, Seoul, Korea) by a surgical team composed of 2 endoscopic skull base neurosurgeons (D.-S. K. and D.-H. N.) and an otolaryngologist (S. D. H.). The details of the surgical technique have been described previously.25-27 Of 482 patients who underwent EES during the study period, visual acuity (VA), visual field (VF), and pRNFL thickness using OCT were assessed pre- and postoperatively in 122 patients.
Comparison of pituitary stalk angle, inter-neural angle and optic tract angle in relation to optic chiasm location on 3-dimensional magnetic resonance imaging
2019, Journal of Clinical NeuroscienceCitation Excerpt :In such cases, transfrontal, trans-sphenoidal corridor or opening the lamina terminalis could be an alternative [1,15]. Also, the height of optic chiasm is of endoscopic relevance as low-lying chiasm reduces the surgical working space in endoscopic endo-nasal approach for retrochiasmatic craniopharyngiomas [16]. 3D CISS sequence is a gradient echo sequence with accentuation of the T2 values and suppression of banding artifacts produced by field inhomogeneities and unbalanced gradients [4].
Conflict of interest statement: This research was supported by a grant from the Korea Health Technology R&D Project through the Korea Health Industry Development Institute (KHIDI), funded by the Ministry of Health & Welfare, Republic of Korea (HI14C3418 and HI16C-1111-020016), a grant (NRF-2015M3A9A7029740, NRF-2015M3C9A1044522, NRF-2015M3A9B5053642, and NRF-2017R1A2B2008412) of the National Research Foundation funded by the Ministry of Science, ICT and Future Planning (MSIP) of Korea, and by a Samsung Medical Center grant.
Kyung Hwan Kim and Yong Hwy Kim contributed equally to this work.