Craniopharyngioma endoscopic endonasal approach
Craniopharyngioma surgery has evolved over the last two decades. Traditional transcranial microsurgical approaches were the only option until the advent of the endoscopic endonasal approach 1).
The endoscopic endonasal approach for craniopharyngiomas is increasingly used as an alternative to microsurgical transsphenoidal or transcranial approaches. It is a step forward in treatment, providing improved resection rates and better visual outcome. Especially in retrochiasmatic tumors, this approach provides better lesion access and reduces the degree of manipulations of the optic apparatus. The panoramic view offered by endoscopy and the use of angulated optics allows the removal of lesions extending far into the third ventricle avoiding microsurgical brain splitting. Intensive training is required to perform this surgery 2).
The highest priority of current surgical craniopharyngioma treatment is to maximize tumor removal without compromising the patients’ long-term functional outcome. Surgical damage to the hypothalamus may be avoided or at least ameliorated with a precise knowledge regarding the type of adherence for each case.
Endoscopic endonasal approach, has been shown to achieve higher rates of hypothalamic preservation regardless of the degree of involvement by tumor 3) 4).
Qiao et al., conducted a systematic review and meta-analysis. They conducted a comprehensive search of PubMed to identify relevant studies. Pituitary, hypothalamus functions and recurrence were used as outcome measures. A total of 39 cohort studies involving 3079 adult patients were included in the comparison. Among these studies, 752 patients across 17 studies underwent endoscopic transsphenoidal resection, and 2327 patients across 23 studies underwent transcranial resection. More patients in the endoscopic group (75.7%) had visual symptoms and endocrine symptoms (60.2%) than did patients in the transcranial group (67.0%, p = 0.038 and 42.0%, p = 0.016). There was no significant difference in hypopituitarism and pan-hypopituitarism after surgery between the two groups: 72.2% and 43.7% of the patients in endoscopic group compared to 80.7% and 48.3% in the transcranial group (p = 0.140 and p = 0.713). We observed same proportions of transient and permanent diabetes insipidus in both groups. Similar recurrence was observed in both groups (p = 0.131). Pooled analysis showed that neither weight gain (p = 0.406) nor memory impairment (p = 0.995) differed between the two groups. Meta-regression analysis revealed that gross total resection contributed to the heterogeneity of recurrence proportion (p < 0.001). They observed similar proportions of endocrine outcomes and recurrence in both endoscopic and transcranial groups. More recurrences were observed in studies with lower proportions of gross total resection 5).
The extended endoscopic transsphenoidal approach has been more recently developed as a potentially surgically aggressive, yet minimal access, alternative.
Komotar et al performed a systematic review of the available published reports after endoscope-assisted endonasal approaches and compared their results with transsphenoidal purely microscope-based or transcranial microscope-based techniques.
The endoscopic endonasal approach is a safe and effective alternative for the treatment of certain craniopharyngiomas. Larger lesions with more lateral extension may be more suitable for an open approach, and further follow-up is needed to assess the long-term efficacy of this minimal access approach 6)
Extended endoscopic transsphenoidal approach have gained interest. Surgeons have advocated for both approaches, and at present there is no consensus whether one approach is superior to the other.
With the widespread use of endoscopes in endonasal surgery, the endoscopic transtuberculum transplanum approach have been proposed as an alternative surgical route for removal of different types of suprasellar tumors, including solid craniopharyngiomas in patients with normal pituitary function and small sella.
As part of a minimally disruptive treatment paradigm, the extended endoscopic transsphenoidal approach has the potential to improve rates of resection, improve postoperative visual recovery, and minimize surgical morbidity 7).
The endoscopic endonasal approach has become a valid surgical technique for the management of craniopharyngiomas. It provides an excellent corridor to infra- and supradiaphragmatic midline craniopharyngiomas, including the management of lesions extending into the third ventricle chamber. Even though indications for this approach are rigorously lesion based, the data confirm its effectiveness in a large patient series 8).
The endoscopic endonasal approach offers advantages in the management of craniopharyngiomas that historically have been approached via the transsphenoidal approach (i.e., purely intrasellar or intra-suprasellar infradiaphragmatic, preferably cystic lesions in patients with panhypopituitarism).
Use of the extended endoscopic endonasal approach overcomes the limits of the transsphenoidal route to the sella enabling the management of different purely suprasellar and retrosellar cystic/solid craniopharyngiomas, regardless of the sellar size or pituitary function 9).
They provide acceptable results comparable to those for traditional craniotomies. Endoscopic endonasal surgery is not limited to adults and actually shows higher resection rates in the pediatric population 10).
Craniopharyngioma endoscopic endonasal approach complications.
see Craniopharyngioma endoscopic endonasal approach case series.