Anterior Skull Base Surgery
Fellowship-trained skull base neurosurgeons • 12 hospital affiliations across New JerseyAnterior skull base surgery treats tumors, vascular lesions, and cerebrospinal fluid (CSF) leaks located at the front of the skull base, including the cribriform plate, olfactory groove, planum sphenoidale, and anterior cranial fossa. Depending on the location and extent of the lesion, surgery may be performed through an open craniotomy, an endoscopic endonasal approach, or a combination of both. The most appropriate approach is determined by the anatomy, surrounding critical structures, and the goals of treatment.
Key takeaways
- The anterior skull base forms the floor of the front of the brain and separates the brain from the nasal cavity and sinuses.
- Common conditions include olfactory groove meningiomas, planum sphenoidale meningiomas, esthesioneuroblastomas, CSF leaks, and selected skull base tumors.
- Depending on the location and extent of the lesion, surgery may be performed through an open craniotomy, an endoscopic endonasal approach, or a combination of both.
- Preserving neurological function including vision, smell when possible, and brain function is a primary goal of surgery.
- Atlantic Brain and Spine's multidisciplinary Skull Base Program tailors the surgical approach to each patient's anatomy, diagnosis, and treatment goals.
| Region | Anterior skull base (cribriform plate, olfactory groove, planum sphenoidale, and anterior cranial fossa) |
| Open approaches | Bifrontal craniotomy or unilateral subfrontal craniotomy |
| Endoscopic approach | Endoscopic endonasal surgery for midline and selected anterior skull base lesions |
| Anesthesia | General anesthesia; multidisciplinary neurosurgery and ENT team for endoscopic cases |
| Conditions treated | Olfactory groove meningioma, esthesioneuroblastoma, cerebrospinal fluid (CSF) leak, anterior skull base tumors, and encephalocele |
| Hospital stay | Typically 2 to 5 nights after open surgery; 2 to 3 nights after endoscopic endonasal surgery |
Timing and stay vary by patient and complexity. Your surgeon will confirm what to expect in your case.
Understanding the anterior skull base
The anterior skull base forms the bony floor separating the brain from the nasal passages and eye sockets. It includes the cribriform plate, olfactory groove, and planum sphenoidale structures located immediately adjacent to the frontal lobes, olfactory nerves, optic nerves, and major blood vessels. Because of this complex anatomy, surgery in this region requires meticulous planning and specialized skull base expertise.
Key surgical considerations include:
- Olfactory nerves — Tumors involving the olfactory groove may surround or compress the nerves responsible for smell. Depending on the tumor’s size and location, preserving the sense of smell may not always be possible.
- Cerebrospinal fluid (CSF) barrier — The thin cribriform plate separates the brain from the nasal cavity. If this barrier is opened during surgery, it must be carefully reconstructed to prevent a cerebrospinal fluid leak and reduce the risk of infection.
- Frontal lobe protection — Open approaches require gentle handling of the frontal lobes, while endoscopic endonasal surgery can avoid or minimize brain retraction for appropriately selected midline lesions.
- Critical blood vessels — Tumors in this region may receive blood supply from the anterior ethmoidal arteries and other skull base vessels. Careful identification and control of these vessels are essential for safe tumor removal.
Open versus endoscopic anterior skull base surgery
Open bifrontal craniotomy
For large olfactory groove meningiomas, planum sphenoidale meningiomas with significant lateral extension, and other complex anterior skull base tumors, a bifrontal craniotomy provides the broadest surgical exposure for safe tumor removal. Through a coronal incision hidden behind the hairline, the surgeon creates a bilateral frontal bone opening and gently elevates the frontal lobes to directly visualize the anterior skull base and surrounding critical structures.
Endoscopic endonasal approach
For carefully selected midline anterior skull base lesions—including craniopharyngiomas, cerebrospinal fluid (CSF) leaks, and selected planum sphenoidale meningiomas—an endoscopic endonasal approach allows surgeons to reach the tumor entirely through the nostrils. This technique avoids an external incision and, in appropriate patients, minimizes or eliminates frontal lobe retraction. See endoscopic endonasal surgery.
Combined approach
Some large or complex tumors extend both above the skull base and into the nasal cavity or paranasal sinuses. In these situations, a combined open and endoscopic approach may provide the safest and most complete access to the lesion. The multidisciplinary skull base team carefully evaluates each case to determine the approach that offers the greatest opportunity for effective treatment while preserving neurological function and quality of life.
Benefits and risks
Potential benefits
- Tailors the surgical approach to the patient's anatomy, diagnosis, and treatment goals.
- Allows complete or maximal safe removal of appropriately selected anterior skull base lesions while preserving neurological function whenever possible.
- Endoscopic approaches eliminate external incisions and may reduce brain retraction for carefully selected midline lesions.
- Repair of anterior skull base CSF leaks helps prevent recurrent meningitis and restores the normal barrier between the brain and nasal cavity.
Possible risks
- Loss or reduction of the sense of smell may occur when the tumor involves the olfactory nerves or olfactory groove.
- Cerebrospinal fluid (CSF) leak can occur after surgery but is usually recognized and repaired during surgery or managed successfully if it develops postoperatively.
- Temporary swelling of the frontal lobes, nasal passages, or surrounding tissues may occur depending on the surgical approach.
- Rare injury to the optic nerves, major blood vessels, or structures around the eye because of the complex anatomy of the anterior skull base.
Your surgeon will review the benefits and risks specific to your diagnosis during your consultation.
What recovery looks like
Recovery from anterior skull base surgery depends on the approach used:
- Endonasal approach 2 to 3 nights in hospital. Nasal congestion for 4 to 6 weeks. Return to work in 2 to 3 weeks.
- Open bifrontal craniotomy 3 to 5 nights in hospital. Frontal headache and periorbital swelling are common for 1 to 2 weeks.
- Weeks 2 to 4 Gradual return to normal activity. ENT follow-up for nasal debridement if endonasal approach was used.
- 3 to 6 months MRI confirms extent of resection. Radiation oncology consultation if incomplete resection of malignant lesion.
Frequently asked questions
What is an olfactory groove meningioma
An olfactory groove meningioma is a benign brain tumor arising from the meningeal coverings at the cribriform plate the area of the anterior skull base through which the olfactory nerves pass. As it grows, it compresses the frontal lobes and often destroys the olfactory tracts, causing loss of smell. Large tumors can cause frontal lobe symptoms including personality changes, cognitive decline, and vision changes from optic nerve compression. Complete surgical removal is curative in most cases.
What is an esthesioneuroblastoma?
Esthesioneuroblastoma (olfactory neuroblastoma) is a malignant tumor arising from the olfactory epithelium in the nasal cavity, which can invade the anterior skull base and frontal fossa. Treatment requires combined surgery and radiation therapy, often with chemotherapy. Surgical resection may require both an open craniotomy and an endoscopic or open nasal approach, coordinated with ENT oncology.
Can anterior skull base CSF leaks be repaired endoscopically?
Yes, Most anterior skull base CSF leaks whether post-traumatic, post-surgical, or spontaneous can be repaired endoscopically through the nostrils using a vascularized nasal mucosal flap (Hadad flap). Endoscopic repair has replaced open craniotomy repair as the standard approach for most CSF leak cases because it avoids external incision, frontal lobe retraction, and the associated complications.
How do you decide between an open craniotomy and an endoscopic endonasal approach?
The choice depends on the tumor’s location, size, extent, and relationship to nearby nerves and blood vessels. Endoscopic endonasal surgery is often the preferred approach for carefully selected tumors located in the midline of the skull base because it reaches the lesion through the natural corridor of the nasal passages, avoiding an external incision and minimizing brain retraction. Open craniotomy may be the better option for tumors that extend laterally, involve critical blood vessels or nerves, or require a wider surgical view for safe removal. In some complex cases, a combined open and endoscopic approach offers the safest and most complete treatment. Every case is reviewed individually by Atlantic Brain and Spine’s multidisciplinary Skull Base Program. The recommended approach is based on the tumor’s anatomy, surrounding critical structures, expected neurological outcomes, and the treatment goals not simply on whether an operation can be performed through the nose or through a craniotomy.
This page is for general education and does not replace medical advice. Treatment decisions should be made with a qualified neurosurgeon based on your individual diagnosis and imaging. To discuss your options, call Atlantic Brain and Spine at 973.993.7100 or request a consultation.
Skull Base Surgery Specialists at Atlantic Brain and Spine
Your care is provided by Atlantic Brain and Spine's multidisciplinary Skull Base Program, bringing together fellowship-trained skull base neurosurgeons, ENT skull base surgeons, neuroradiology, radiation oncology, neuro-oncology, and other specialists as needed.
