Surgical Navigation Systems
Surgical navigation systems are popular tools during sinus and skull base surgery, which allow the surgeon to upload CT scans of individual patients into a computer. The scans are then synchronized with the surgical instruments, so that the exact location of the surgical instrument can be visualized in relation to its whereabouts on the patients 3D CT scan rendering. This allows the surgeon to localize key structures, and validate spatial anatomy that is seen endoscopically. Image guidance systems are a valuable tool in preventing injury to these key structures.
Endoscopic Pituitary Adenoma Resection
Endoscopic Pituitary resection via a trans-sphenoidal approach is relatively noninvasive, using the nasal passages and knowledge of the anatomy of the paranasal sinuses to navigate to the base of the skull. Both sides of the nasal passages are accessed, and traditionally a portion of the posterior nasal septum is resected to create a window, allowing surgical instrumentation via both nasal passages simultaneously.
Once the skull base underlying the pituitary gland is encountered (the sella turcica), the bony skull base can be drilled away in order to expose the pituitary adenoma. Commonly, a skilled Otolaryngologist will perform this portion of the procedure to provide adequate exposure for the Neurosurgeon. Next, the neurosurgeon will perform the pituitary adenoma resection through on nasal passage, while the Otolaryngologist controls an endoscopic camera in the contralateral nasal passage to provide visualization.
Pituitary adenomas are benign tumors of the anterior pituitary gland, with incidence rates between 4 and 78 per 100,000 individuals. They are more common in individuals with Multiple Endocrine Neoplasia type 1, who may develop tumors of the parathyroids, pancreas, and pituitary glands. These tumors can be functional (secreting hormones) or nonfunctional (not secreting hormones).
Large tumors of the pituitary can lead to vision problems, blindness, headaches, cerebrospinal fluid leaks, meningitis, altered thyroid function, Cushing disease, gynecomastia, and growth hormone alteration. CT scans are used in the diagnosis and surgical planning for pituitary adenoma resection. It is recommended that tumors having these effects are treated with surgical resection.
The StealthStation surgical navigation system allows you to see your instrument tip on the screen, which allows a safer and more thorough resection, and can decrease the chances of violating important anatomic structures. Knowledge of precise surgical location is important during skull base surgery, as vital structures such as the brain, carotid arteries, optic nerves, and orbit are all in close proximity.
The CT image uploaded must be fine cut(1mm slices). Image guidance is used to confirm the correct location when resection a portion of the posterior nasal septum, and when drilling away the skull base directly inferior to the pituitary adenoma. Once the adenoma is located, the StealthStation guidance is used to demarcate the extent of skull base that must be resected in order to completely visualize and remove the tumor.