Abstract
A.B. Kassam; P.A. Gardner*; C.H.
Snyderman; R.L. Carrau; A.H. Mintz; D.M. Prevedello
Objective
Craniopharyngiomas
are notoriously difficult to treat. Surgeons must weigh the risks of aggressive
resection against the long-term challenges of recurrence. Because of their
parasellar location, often extending well beyond the sella, these tumors
challenge vision and pituitary and hypothalamic function. New techniques are
needed to improve outcomes in patients with these tumors while decreasing
treatment morbidity. An endoscopic expanded endonasal approach (EEA) is one
such technique that warrants understanding and evaluation. The authors explain
the techniques and approach used for the endoscopic endonasal resection of
suprasellar craniopharyngiomas and introduce a tumor classification scheme.
Methods
The techniques and
approach used for the endoscopic, endonasal resection of suprasellar
craniopharyngiomas is explained, including the introduction of a tumor
classification scheme. This scheme is helpful for understanding both the
appropriate expanded approach as well as relevant involved anatomy.
Results
The classification
scheme divides tumors according to their suprasellar extension: Type I is
preinfundibular; Type II is transinfundibular (extending into the stalk); Type
III is retroinfundibular, extending behind the gland and stalk, and has 2
subdivisions (IIIa, extending into the third ventricle; and IIIb, extending
into the interpeduncular cistern); and Type IV is isolated to the third
ventricle and/or optic recess and is not accessible via an endonasal approach.
Conclusions
The endoscopic EEA
requires a thorough understanding of both sinus and skull base anatomy.
Moreover, in its application for craniopharyngiomas, an understanding of tumor
growth and extension with respect to the optic chiasm and infundibulum is
critical to safely approach the lesion via an endonasal route.