Beverly Hills Skull Base Center
Beverly Hills Skull Base Center
A pituitary adenoma is a specific type of brain tumor that arises from the pituitary gland. This gland is situated directly behind the nose, under the frontal lobes of the brain. It controls the regulation of many different hormones and is vital to life. These adenomas secrete hormones, some active others not, and symptoms depend on the type of hormone secreted. The most common hormone produced by one of these tumors is PROLACTIN which can cause impotence in males and infertility in females. The next most common is an INACTIVE HORMONE that usually causes symptoms related to the size of the tumor and the pressure it causes on surrounding structures such as the visual pathways, the normal pituitary gland and the brain itself. The next most common adenoma produces GROWTH HORMONE which can cause excessive growth in children or acromegaly in adults. The least common hormone secreted by a pituitary adenoma is ACTH which causes Cushing's disease. Most adenomas are benign and can be cured with surgery, medicine, radiotherapy or combinations of all 3 treatments. Tumors of the pituitary gland have traditionally been treated either with medicine or by surgical removal. Surgical removal commonly takes the form of transsphenoidal excision. Until recently, this required making a cut under the lip or within the nose. While highly effective, this surgery has been improved by incorporating the neuroendoscope. Most surgeries can be performed endoscopically through the nostril using an endonasal approach. For the patient, this means a quicker surgery that is less invasive with fewer complications and reduced discomfort. Hospitalization is typically two days or less.
Trigeminal neuralgia (TN) is a disorder characterized by severe electrical pain involving the face. Usually arising in middle age, this form of facial pain is most commonly, although not exclusively, seen in women. The discomfort can be brought on by brushing of the teeth, stoking of the face or even exposure of the face to wind. In many cases, the symptoms can mimic dental disease resulting in unnecessary tooth extractions. The first line treatment for trigeminal neuralgia is medical. Only when a patient fails medical treatment or cannot tolerate medicine is surgery necessary. Surgical alternatives include percutaneous methods (insertion of needles to anesthetize the nerve), radiation (stereotactic radiosurgery) or microvascular decompression (MVD). It is generally believed that most cases of typical TN are causes by an artery, or less commonly a vein, compressing the nerve that gives sensation to the face, the trigeminal nerve. By rubbing and pressing on the nerve the artery causes a type of short circuiting that results in the electrical pain experienced by the patient. Microvascular decompression surgery consists of exposing the trigeminal nerve where it enters the brainstem and identifying the artery that is compressing the nerve. A small piece of Teflon or similar tissue is placed between the artery and nerve to act as a shock absorbing. Using endoscope-assisted techniques this surgery can be performed in a less invasive manner with excellent results.
Uncontrollable twitching and spasms of one side of the face can be minor or in many cases quite disfiguring. Frequently, the person who suffers from Hemifacial Spasm (HFS) becomes so self-conscious about their appearance that they resort to limited person to person interaction. This can have a tremendous personal and professional impact. In many cases this can be adequately, although temporarily, controlled using medications (injected). However, minimally invasive, endoscope-assisted surgery can result in permanent significant improvement or cure in the majority of patients with HFS. Similar to trigeminal neuralgia, it is known that the majority of patients with HFS have an artery compressing the facial nerve where it exits the brainstem. By rubbing and pressing on the nerve, the artery causes a type of short circuiting, that results in the electrical pain experienced by the patient. Microvascular decompression surgery consists of exposing the trigeminal nerve where it enters the brainstem and identifying the artery that is compressing the nerve. A small piece of Teflon or similar tissue is placed between the artery and nerve to act as a shock absorbing.
Acoustic tumors or more properly called Vestibular Schwannomas account for 8% of all intracranial tumors. They are more common in females, usually present with unilateral hearing loss or ringing in the ear, and are mostly slow growing (approx. 1 mm per year). The prognosis is usually very good when they are treated. In most cases this requires surgery. If the patient is opposed to surgery or is unfit for surgery because of advanced age or associated medical problems then watching them for a while is not unreasonable. If the growth rate is slow then they may never get big enough to cause any other problem apart from hearing loss. If, however, the tumor grows bigger while being followed, then surgery and radiotherapy are riskier. The major risk from surgery is hearing loss, which is not that disturbing in most patients who present with hearing loss, and facial nerve damage, which causes asymmetry of the face. The risk is directly related to the size of the tumor and the skill of the operating surgeon. Radiosurgery using focused beams of radiation such as that with the Gamma Knife has been successful in arresting the growth of some tumors, but may only have a limited effect and may cause delayed damage to the facial nerve. If the tumor is incompletely removed it will recur. Other complications of surgery include spinal fluid leakage, chronic headache and persistent ringing in the ear if the damaged acoustic nerve is preserved. If you would like to see the human side of this tumor, read “My Brain Tumor”, a play written by a patient with an acoustic neuroma.
CSF Rhinorrhea occurs when there is a communication between the intracranial cavity and the nasal cavity, thus allowing the fluid surrounding the brain to leak into the nose. In addition to leakage of CSF, this communication pathway allows bacteria direct access to the brain and leads to life-threatening infections. A breach in the plate separating the brain from the nasal cavity (cribriform plate) occurs due traumatic injury, sinus infection, and at times without a clear etiology. A variety of imaging studies can be used to confirm the diagnosis and the location of the leak. Closure of larger defects requires a combined nasal and intracranial approach with complex reconstructive procedure. Most CSF leaks can be closed via an intranasal endoscopic approach with image guidance systems. This type of approach has a high success rate while allowing for a quick recovery.
Optic Nerve Decompression
The optic nerve is leaves the orbit and travels through a boney canal at the root of the eye. The medial wall of this canal separates it from the nasal sinuses. Traumatic injury to this area causes not only swelling of the nerve in the confines of the boney canal that causes essentially strangulation of the nerve, but also boney fragments may impinge on the nerve. This area may be accessed through intranasal endoscopic approach. The boney medial wall of the orbit can be removed along with any bone fragments thus decompressing the nerve and preventing any further injury.
Thyroid dysfunction, specifically Grave’s disease, leads to thyroid ophthalmopathy. Afflicted patients suffer from a characteristic wide stare that result from deposition of material in orbital tissue and thus a protuberant eye. Previously, open approaches were used to remove parts of the orbital wall that would allow the enlarged orbital tissue to decompress partly in the nasal cavity and the globe to recesses back into the orbit. Advanced endoscopic techniques allow access to the orbital walls through the nose. This minimally invasive approach show immediate results with minimal risks and a speedy recovery.