Minimally Invasive Brain Surgery
Learn About Different Keyhole Approaches:
- endoscopic endonasal
- endoscopic transventricular
- brain port
Supraorbital Eyebrow Approach
The supraorbital eyebrow approach is useful for many patients with meningiomas, craniopharyngiomas and other tumors near the optic nerves and pituitary gland, as well as gliomas and metastatic brain tumors in the frontal and temporal lobes.
This versatile, minimally invasive approach minimizes normal tissue disruption and brain retraction, allowing for a more direct approach to these lesions. Occasionally, an abdominal fat graft may be necessary to seal large nasal sinus defects.
This approach is typically performed with the assistance of an endoscope, allowing for further visualization. As such, patients recover well and have good cosmetic outcomes long term.
At the Pacific Brain Tumor Center, we have extensive experience with this approach, helping pioneer this operation since its introduction. We have published extensively on this topic.
Endoscopic Endonasal Approach (through the nostrils)
Endoscopic Endonasal Surgery (through the nostrils) is ideal for most pituitary adenomas, craniopharyngiomas, chordomas, sinus carcinomas, olfactory neuroblastomas and some midline meningiomas of the tuberculum sellae, clivus, cavernous sinus, Meckel’s cave, orbital apex and orbit. We have published extensively on this topic.
This approach minimizes normal tissue disruptions and brain retraction while maintaining a cosmetic outcome. The Mini-Pterional Approach offers a direct avenue for certain sphenoid wing and parasellar meningiomas, other tumors of the cavernous sinus and Meckel’s cave, orbital lesions as well as temporal lobe gliomas and metastatic brain tumors.
Typically, this operation is assisted with endoscopic visualization, allowing for increased visualization of the structures in the region. Patients recover relatively quickly in comparison with traditional pterional operations, with potentially less pain, chewing difficulties and facial muscle atrophy.
Retromastoid Approach (behind the ear)
The retromastoid approach (also known as the retrosigmoid approach) uses a small window behind the ear to reach and remove acoustic and trigeminal schwannomas, meningiomas, epidermoid tumors, and tumors of the cerebellum such as hemangioblastomas and metastatic brain tumors.
It is also the main approach for microvascular decompression of the cranial nerves (for trigeminal neuralgia or hemifacial spasm). This operation is augmented with the introduction of the endoscope, allowing for visualization around corners, limiting the need for extensive tissue removal or brain retraction.
Occasionally, an abdominal fat graft is necessary to seal the opening and prevent a cerebrospinal fluid (CSF) leak. Overall, this operation is associated with great access to the pathology with minimal cosmetic or soft-tissue damage and relatively quick patient recovery.
By using gravity to allow for the normal brain to fall away, there is no need for brain retraction and there is minimal normal brain traversed to reach these midline, deep lesions.
The gravity-assisted Trans-Falcine approach is ideal for the resection of meningiomas, gliomas (astrocytomas, ependymomas, oligodendrogliomas, intraventricular tumors) and metastatic brain tumors. The angled endoscopes allow for excellent visualization and the potential of maximal safe tumor resection.
Compared to traditional approaches, patients have a relatively quicker recovery and the potential of increased preservation of neurological function.
This approach takes advantage of the normal structures separating the cerebral cortex from the other structures of the hindbrain and brainstem, minimizing the need for brain retraction.
The gravity-assisted trans-tentorial approach is ideal for patients with certain pineal tumors and cysts, gliomas, metastatic tumors and cerebral cavernous malformations of the inferior-medial posterior temporal and occipital lobes.
The operation is performed in a sitting position to achieve this relaxation. Patients will require a pre-operative cardiac evaluation to ensure safe surgical outcomes. This procedure is performed endoscopically, allowing for improved visualization and a smaller craniotomy.
Compared with other approaches, this has less risk to the occipital lobes (vision processing region) and decreased disruption of normal tissue and brain.
Endoscopic Trans-Ventricular Route
For tumors and cysts within the ventricles: colloid cyts, gliomas, metastatic brain tumors and pineal tumors.
Brain Port Approach
The Brain Port approach is used for gliomas, metastatic brain tumors and cerebral cavernous malformations deep within the brain. Challenging deep-seated brain tumors and blood clots can be reached while minimizing the risk of damaging the surrounding dense and delicate neural structures that control brain and body functions. Using a tool called BrainPath®, Pacific Brain Tumor Center neurosurgeons can navigate between the natural folds and neural structures in the brain, to minimize collateral damage to the surrounding brain along the path to reach the tumor or blood clot.