A surgery by Dr. Luis Borba
Retrochiasmatic craniopharyngioma presents one of the most complex challenges in skull base surgery. Its close relationship with the optic chiasm, hypothalamus, anterior circulation perforators, and deep structures of the third ventricle demands rigorous planning and an approach that maximizes visualization without compromising critical structures. In this masterful surgery, available in exclusive in the app SurgSchool, the Dr. Luis Borba, President-Elect of the World Federation of Neurosurgical Societies (WFNS), shows a complete microsurgical resection of a retrochiasmatic craniopharyngioma by means of a modified posterior petrous approach, a strategic alternative for tumors with retrochiasmatic projection and posterior suprasellar extension.
Clinical presentation and preoperative studies
The patient, a nine-year-old boy, presented with a one-year history of progressive headaches, followed by nausea, vomiting, and diplopia. On admission, he exhibited confusion and drowsiness, conditioned by a obstructive hydrocephalus, which required urgent placement of a ventriculoperitoneal shunt.
The magnetic resonance imaging revealed a solid-cystic mass of 4,5 × 3,6 × 3,3 cm, with marked suprasellar extension, obliteration of the third ventricle and projection towards the interpeduncular and prepontine cisterns. The mural nodule enhanced heterogeneously, with calcifications visible on the CT scan. The vascular pattern showed a right fetal posterior cerebral artery and anterior cerebral arteries not displaced above, a key finding that confirms an origin retrochiasmatic.
Approach selection: why a modified posterior petrous bone
Dr. Borba rules out:
- Transcallus route, due to the risk of hypothalamic injury when accessing a tumor with a marked superior projection.
- Subfrontal and pterional approaches, insufficient because it is an injury located further back than usual.
- Endoscopic endonasal approach, potentially useful but limited by the superior and lateral extension, the relationship with perforators and the possible impossibility of maneuvers such as pituitary transposition or sectioning of the stalk.
El modified posterior petrous approach provides:
- A direct view of the retrochiasmatic component.
- Multiple working angles towards the interpeduncle and the third ventricle.
- Lower risk of traction on the chiasm and hypothalamus.
- Safe access to preserve perforators from the previous circulation.
Bone opening and exposure
After positioning the patient in the supine position with contralateral head rotation, an arcuate incision is made, and the fascia and temporalis muscle are dissected. Following Dr. Borba's practice, the surgery begins with mastoidectomy, identifying the sigmoid sinus and allowing limited mobilization of it.
The following steps are taken:
- Double dural incision (basal and presigmoid temporal).
- Coagulation and sectioning of the superior petrosal sinus.
- Complete section of the tentorium up to the incisura, with mandatory identification of IV cranial nerve before the final cut.
This step creates a expanded presigmoid corridor, with combined infra- and supratentorial access.
Tumor resection: circumferential dissection and preservation of arachnoid planes
The approach allows exposure of the posterior wall of the cyst, which initially drains to reduce tension. Subsequently, Dr. Borba performs a circumferential microsurgical dissection of the capsule, systematically preserving the arachnoid planes, key to preventing hypothalamic injury and vascular damage.
During the resection:
- They are identified and protected perforators of the carotid artery and anterior circulation.
- The projections are precisely dissected. lower, anterior, and upper.
- The capsule separates from the floor of the third ventriclepreserving it completely.
Thanks to the initial decompression and the quality of the corridor, a en bloc resection of the tumor, including the entire capsule.
Endoscopic visualization and final verification
El Dr. Borba Use an endoscope to inspect:
- Surgical cavity.
- Optic chiasm, optic nerves and optic tracts.
- Posterior and perforating cerebral arteries.
- cranial nerves III and IV.
The review confirms absence of residual tumor.
Closure and postoperative evolution
The reconstruction is performed using techniques specific to skull base surgery, prioritizing watertightness and compartment separation.
The postoperative period shows:
- Complete resection in neuroimaging.
- Absence of neurological deficits.
- Triphasic diabetes insipidus transitional with progressive resolution.
- Hypothyroidism and hypocortisolism treated adequately, with suspected GH deficiency under follow-up.
Why this surgery is a benchmark in SurgSchool
This case of a retrochiasmatic craniopharyngioma offers exceptional learning for skull base neurosurgeons and neuro-oncologists:
- Rational selection of the posterior petrous approach.
- Management of complex retrochiasmatic craniopharyngiomas.
- Advanced circumferential dissection techniques preserving arachnoid planes.
- Protection from penetrators and three-dimensional anatomical analysis.
- Pediatric surgery in deep territories with postoperative endocrinological control.
Access the full video at SurgSchool
The complete surgery, narrated and subtitled in Spanish and English, is available in exclusive in the surgical training app SurgSchool.
