1. Correct diagnosis, based on a careful analysis of the clinical history and examination, is critical to therapeutic success.
2.  MRI must be done to rule out the presence of:

MS

Mass lesion (tumor or cyst)

Vascular compression

3. All trigeminal neuralgia patients should undergo a trial of medical therapy.

4. Surgery is to be considered when medical therapy fails, or the patient experiences significant side-effects.

5. Approximately 50% of patients will eventually require surgery due to failed medical therapy.

6. TN patients should be aware of all – ablative vs. non-ablative – surgical options.

7.   For non-MS patients with evidence of vascular compression on the MRI scan, MVD is  the treatment of choice:

Surgery is simplified (minimally invasive surgery)

4-cm incision,

<2-cm bone opening (“suboccipital craniectomy”)

45-minute surgery

Foley catheter not needed (for bladder drainage during surgery)

Minimal blood loss, avoiding blood transfusion

1-2 days of hospital stay

Negligible permanent facial numbness as compared  to 80% following ablative surgery

The patient is positioned lying flat (“supine position”) with a small area behind the right ear shaved, and the incision marked.

A 4 to 4.5 cm-incision is marked (1 ¾”) behind the right ear.

The size of bone opening (“craniotomy” or “craniectomy”) shown above is 15 mm, which is less than the diameter of a dime (18 mm).

Exposure of the right trigeminal nerve (“N”) and the surrounding vein (“V”) and artery (unmarked, on the far side between the vein and nerve).

Surgical instruments – suction on the left and bipolar electro-cautery forceps on the right – being used through the bone opening.

The offending artery (“A”) is being dissected away from the nerve (“N”) with a micro-instrument (appearing blurry, just below the letter “A” marking the offending artery).

The offending artery is completely separated far away from the nerve.

A Teflon felt is placed between the trigeminal nerve and the surrounding artery (now covered by the felt), completely relieving pressure off of the trigeminal nerve, thereby completing the surgery of “microvascular decompression” (“MVD”).

Surgery is considered when (1) medical therapy fails to adequately control trigeminal neuralgia, (2) patients are unable to tolerate medications’ side-effects, or (3) patients do not like the prospect of being on long-term medications. 

Surgical Options:

A) Ablative (“to destroy a function by application of a noxious substance”) Surgery:

For some unknown reason, when a segment of the trigeminal nerve is “damaged” (by way of “lesioning” or “ablation” applied to it) by a noxious agent, trigeminal neuralgia pain disappears or improves.  There are several surgical means of creating a focal area of “ablation” to the trigeminal nerve, and these include:

Gamma Knife (GK) Radiosurgery –

A single shot, focused radiation targeted to the trigeminal nerve

Balloon Compression Rhizotomy –

Lesioning by way of a mechanical compression to the nerve

Glycerol Rhyzotomy –

Chemical lesioning to the nerve by a type of alcohol

Radiofrequency (RF) Rhizotomy

Thermal (heat) lesioning to the nerve by RF

Long-term success rates:  Glycerol 60%, Gamma Knife 65%, Balloon 67%, RF 75%

Advantages:

Short operative time (15 to 45 minutes)

Avoids general anesthesia, performed under IV sedation/local anesthetic

Good initial pain relief

Same-day procedure and quick recovery

Disadvantages:

Permanent facial numbness – RF 80%, Balloon 50%, Glycerol & GK 30%

Significant pain during surgery (performed without general anesthesia)

Need to repeat procedures due to relatively high pain recurrence rates

      Indications for Ablative Surgery:  (When to proceed with ablative surgery?) 

1. Trigeminal neuralgia patients with MS (multiple sclerosis).
2. Trigeminal neuralgia patients with no clear vascular compression on the preoperative MRI.
3. Trigeminal neuralgia patients with significant medical illnesses which preclude major surgery under general anesthesia.
4. Patient’s personal choice after thorough discussion of all options.
5. Which specific ablative procedure to be done depends on the individual surgeon’s personal experience and choice.

B) Non-Ablative Surgery: Microvascular Decompression (MVD)        

The only non-ablative surgical technique available for trigeminal neuralgia patients is microvascular decompression (MVD).

Indications for MVD: 

1. Trigeminal neuralgia patients with clear vascular compression on preoperative MRI.
2. Patients healthy enough to undergo 1 hour of surgery under general anesthesia.
3. Patient’s personal choice after discussion of all treatment options.

Advantages:

High success rate (95% when patients are carefully selected)

Low risk of permanent facial numbness

Minimal complications (when surgeon is experienced)

45-minutes of operative time, avoiding Foley catheter or blood transfusion

Small incision and craniotomy (bone opening)

Fast recovery (1-2 days of hospital stay) 

Disadvantages:

            “Brain surgery” with its associated risks (very small, but present)

            Requires general anesthesia (<1 hour)

Personal Recommendation:  Based on treating trigeminal neuralgia patients for nearly 30 years, my personal recommendation is MVD as it guarantees a high success rate with a low risk of permanent facial numbness.  (95% success rate initially, 75-80%  long-term success rate, <5% permanent numbness)

When evaluating a new patient with trigeminal neuralgia, MRI with and without Gadolinium is done to make certain that there is no underlying mass lesion along the course of the trigeminal nerve (e.g. meningioma, schwannoma, epidermoid, or very rarely, skull base cancer).  At the same time, a special MRI protocol (“CISS” or “FIESTA”) is performed to look for any possible “vascular compression” on the trigeminal nerve.

35 year old female patient’s MRI showing a large tumor arising from the trigeminal nerve (trigeminal schwannoma) as the cause of her trigeminal neuralgia.

72 year old female patient’s MRI showed a massive tumor (meningioma) causing severe compression on the trigeminal nerve causing trigeminal neuralgia, in addition to other symptoms (R sided weakness, walking difficulty and headache).

42 year old patient’s MRI shows the trigeminal nerve (*) compressed by the adjacent arterial loop. Due to the compression, the trigeminal nerve appears thinner than the trigeminal nerve on the opposite side. Additionally, the nerve is “bowed” compared to the nerve that is normal and straight on the opposite side.

I have always felt a great sense of gratitude towards all my former patients who taught me so much about the profession I love.  Two of the most important personal principles of mine in medicine (& neurosurgery) are (1) to treat each patient as family, and (2) to regard each patient as a teacher.  It is this second principle that motivated me throughout my career to conduct research studies, write academic papers, and learn from each of my patients so that my future patients will receive better and improved care.  This handbook is a small token of my deep appreciation to all my patients – my real teachers.  As you read this Handbook, please take a moment to thank those who came before you, without whom this Handbook and the improved care I am now able to provide today would not be possible.

It is my wish and intention that this handbook will give trigeminal neuralgia patients enough basic information about their newly diagnosed condition so that their anxiety is eased, and they are better equipped to make educated treatment decisions.

It is also my great wish that the facts outlined in this handbook will give them hope.  Rather than asking “Why me?” as they suffer through excruciating pain, I want all those who read this to finish the handbook on a positive note, having hope that they indeed have excellent treatment options available to them that will result in relief of this awful condition.

With best wishes,

Joung H. Lee, M.D.
President, Valley Neurosurgical Institute &
Co-Director, Hollywood Presbyterian Neuroscience Institute
www.ValleyNI.com