Quyen T. Nguyen, MD, PhD
Otolaryngology - Head & Neck Surgery
Dr. Quyen T. Nguyen is an Assistant Professor in the UCSD Department of Surgery, Division of Otolaryngology-Head and Neck Surgery. She is fellowship trained in Neurotology/Skull Base Surgery and Board Certified in Otolaryngology - Head and Neck Surgery.
Dr. Nguyen has clinical expertise in the fields of otology and neurotology / skull base surgery. She is practiced in the evaluation and medical/surgical treatment of problems related to the ear, including exostosis (“surfer’s ear”), tympanic membrane perforations, ossicular chain problems, otosclerosis, cholesteatoma, single-sided deafness, Ménière’s disease, and acoustic neuromas.
Quyen Nguyen has been appointed Assistant Professor of Otolaryngology-Head and Neck Surgery in the UCSD Department of Surgery. She has subspecialty fellowship training in Otology and Neurotology. Her clinical interests include otology and neurotology/skull base surgery.
Dr. Nguyen has been awarded a 5-year NIH grant to study the use of molecular fluorescence imaging to guide surgeons in tumor surgery. Using “smart” probes that can differentiate tumor from normal tissue, the goal of this grant is to develop a system that allows surgeons to see the margin between tumor and normal tissue in real time during surgery.
Dr. Nguyen received her combined MD/PhD degrees from Washington University School of Medicine. After completion of her residency training in Otolaryngology-Head and Neck Surgery, she went on to receive subspecialty training in Neurotology/Skull Base Surgery at the University of California, San Diego. Dr. Nguyen is a diplomat of the American Board of Otolaryngology.
Consultation For Acoustic Neuroma
This consultation is part of a series of consultations with Head and Neck Surgery specialists at the University of California, San Diego. In this hypothetical conversation between patient and doctor, we present an example case that is a composite of the most common signs and symptoms we see in patients who have this problem, along with the standard exams and treatments we recommend in a typical case. The discussion is no means exhaustive or comprehensive and the percentages used are only an approximation of those reported in the medical literature.
Whether or how a person is affected by a particular disease or problem can depend on the person’s age, gender, or race. In each consultation we present on the UCSD web site, we will indicate whether gender, age, or race makes a difference. The following consultation about acoustic neuroma could apply to any adult. The condition is most commonly found in men and women aged 30-60 years.
This consultation is presented for purposes of general information. If you think you have a similar condition, please see your doctor to discuss your individual case and the exams and treatments that are best for you.
An acoustic neuroma, also known as a vestibular schwannoma, is a benign (non-cancerous) tumor of the inner ear and intracranial cavity that grows along the course of the eighth cranial nerve, which is the nerve that controls hearing and balance. Most acoustic neuromas grow slowly, causing gradual or sudden loss of hearing in one ear, dizziness, and ringing (tinnitus) in the ear. Acoustic neuroma is one of the most common benign tumors of the brain, and is most often diagnosed in people between the ages of 30 and 60 years. Acoustic neuromas that grow large enough to cause symptoms are fairly rare, occurring in about 1 of every 100,000 people in the United States.
In our example, the patient is a 50-year-old man whose primary care doctor has referred him for evaluation of a progressive loss of hearing in his right ear.
Doctor: Good morning, I’m Dr. Nguyen. How are you today?
Doctor: What brings you to see me?
Patient: I’ve developed a hearing loss in my right ear. My primary care physician ordered a hearing test and then sent me for an evaluation with a local ENT doctor. The ENT doctor looked at the hearing test, examined me, performed an MRI scan, and told me that I needed to come see you.
Doctor: Can you tell me when your hearing loss developed?
Patient: I think I’ve generally had a little bit of hearing loss as I got older, but then all of a sudden, over a period of 6 months, I noticed that the hearing in my right ear seemed to deteriorate. One day, I put the phone up to my ear, and I couldn’t hear anything out of my right ear. That’s when I went to go see my primary care physician.
Doctor: You only noticed the change in your right ear?
Doctor: Is there any ringing associated with it, in either your right or left ear?
Patient: Yes, I have fairly significant ringing in my right ear.
Doctor: Did you ever experience ringing before?
Doctor: Do you experience any vertigo, dizziness, or imbalances?
Patient: What’s vertigo?
Doctor: Vertigo is the feeling of spinning and that the environment is moving when it is not.
Patient: Sort of like when you go on a merry-go-round and get nauseated?
Doctor: Yes, that can be compared to it.
Patient: No, I’ve never experienced vertigo.
Doctor: Any imbalance or problems walking?
Patient: I did have a little off-balanced feeling for a few days about a year ago, but it went away in a couple of days. The doctor thought it might be high blood pressure.
Doctor: Is there any family history of non-cancerous growths in the inner ear or the covering of the brain? These might have been called acoustic neuromas or meningiomas.
Patient: Not that I am aware of.
The doctor then performs an examination and reviews the patient’s medical records.
Doctor: I see that your hearing test shows that you have a unilateral high-frequency sensorineural hearing loss in your right ear. Sometimes this kind of hearing loss is how a small benign tumor on the hearing nerve is first noticed. Your symptoms, with the hearing loss and ringing in one ear, are consistent with what we would see in a person who has one of these benign growths. The next step in diagnosing this type of tumor is to do an MRI, as your ENT doctor did.
Patient: Does my MRI show a tumor like that?
Doctor: Yes. Here on your MRI, we can see what is called a 1.2-cm enhancement of your eighth cranial nerve. That indicates a small growth, or tumor. Though it’s impossible to know exactly what this tumor is, your symptoms and what we see on the MRI scan suggest that it may be an acoustic neuroma, also known as a vestibular schwannoma.
Patient: But it is benign, and not cancer?
Doctor: This is most likely a benign tumor, not a malignancy or cancer. It grows from cells that surround your balance nerve, called Schwann cells. These tumors grow slowly, at a rate of 0-2 mm a year on average. They do not invade surrounding tissues, like a cancer does, and they do not metastasize or spread to other parts of your body.
Patient: Do I need some kind of treatment?
Doctor: There are three treatment options for an acoustic neuroma. When we select treatment for you, we consider your age and the hearing loss that you have already had. You’ve lost the hearing in the affected ear, and it is doubtful that it will come back. An acoustic neuroma can grow to a size that can cause other serious problems, possibly life-threatening problems. But a tumor like this grows so slowly – generally, less than a tenth of an inch a year -- that it can take a number of years before problems occur. And so the first option is observation, where we examine you once a year and watch to see if the tumor grows.
Patient: What are the other serious problems it could cause?
Doctor: The biggest concern is that, as the tumor continues to grow, it can compress the brain stem, as well as compress the other cranial nerves in and around your inner ear. These nerves control your balance and the movements of your face, sensation to your face, taste, swallowing, the movement of your tongue, your vocal cords, and the ability to shrug your shoulder.
Patient: So you’re saying that if I let the tumor grow, not only might I start to develop some dizziness, but I could get a paralyzed face?
Doctor: That is correct. And if the tumor were to compress the brain stem, or other structures in the brain, then there could be life-threatening problems. We would watch you closely by getting yearly MRI scans, and we would monitor the tumor very precisely to see how fast it is growing. If it is not growing at all, we would continue to do annual MRI scans. . If it is continuing to grow, we would go to one of the other two treatment options.
Patient: What are the other options?
Doctor: One option is to remove this tumor surgically. This will require a craniotomy, where we would actually enter your cranial cavity, which contains your brain, and perform the operation under the surgical microscope.
Patient: That’s beginning to sound like brain surgery.
Doctor: It is a brain surgery, and in fact we do this surgery as a team with the neurosurgeons here on staff. Most often, I work with Dr. John Alksne, who is a professor of neurosurgery also at UCSD. The surgery entails making a small hole in your skull behind your ear and, using a high-power surgical microscope, we identify the tumor in the internal auditory canal and remove it.
Patient: How long would I be in the hospital?
Doctor: The procedure requires an overnight stay in the intensive care unit (ICU), and a total of 3-5 days in the hospital, on average.
Patient: Does that surgery take care of the tumor permanently?
Doctor: With the surgery, the plan is to cure you of the tumor by removing it in its entirety. You would still need to have several evaluations and MRI scans to make sure that the tumor has not returned. In some cases, we leave a small amount of tumor on the facial nerve because it would cause paralysis if the very last bit were removed. In these situations, we do follow-up MRIs to determine whether the tumor is growing, but many times they do not grow.
Patient: Would the surgery bring my hearing back?
Doctor: Unfortunately, your hearing in the affected ear is gone, so the surgery will not restore it.
Patient: Are there risks and complications to the surgery?
Doctor: When we do this surgery, our major concern is the nerve that controls movement of your face. That nerve runs in the same canal as the nerve that controls hearing and balance. There is about a 10-20% risk that the nerve that controls movement of your face could temporarily become swollen, and this would result in either a partial or complete paralysis of your face. The majority of patients who have some degree of paralysis gain complete or near-complete return of function within a year. However, some patients -- especially those who have larger tumors -- do not regain full function of the muscles on that side of the face.
Patient: Is my tumor large?
Doctor: Yours is considered a small tumor because it is less than 1.5 cm in size.
Patient: Are there other risks?
Doctor: This surgery has the same risks as many other surgeries. There are risks associated with general anesthesia. There is a risk of bleeding, and a very small risk that you might have a stroke during the procedure. As I mentioned, there is the risk of damage to the nerve that controls function and movement in the face. There is also a risk of infection. The brain floats in a fluid called the cerebrospinal fluid, or CSF. After surgery, there is a small risk that the CSF can leak through the incision site, which creates an avenue for possible infection to the brain.
Patient: Is that like meningitis?
Doctor: Yes, that is meningitis. These complications are not common, but I have seen them before. Meningitis would be treated with antibiotics and would require an extended stay in the ICU. If you had a CSF leak, we would likely handle it conservatively by inserting a small catheter into the small of the back to reduce the spinal fluid pressure. The catheter is called a lumbar drain, and we leave it in place for 3 days. If that doesn’t work, we would open the incision and find exactly where the fluid is leaking and close it water tight.
Patient: What is the third treatment option?
Doctor: The third option is stereotactic radiosurgery-also known as Gammaknife, Cyberknife, or Trilogy. This is a technique using highly focused radiation to treat the tumor. There is no incision. You would receive a single treatment, which usually takes a total of a few hours in the facility, and you would then go home the same day.
Patient: So you’re saying that I can have an outpatient procedure that is over in a few hours versus an operation?
Patient: Why wouldn’t I choose the third option?
Doctor: It is entirely up to you. It is a very attractive alternative to open conventional surgery. The long-term results of the radiation are on par with the results from surgery, but the difference is that tumor is not gone. It undergoes changes from the radiation that are intended to make it stop growing. The risk of facial nerve paralysis and hearing loss from the stereotactic radiosurgery procedure is essentially the same as with surgery.
Patient: Are there disadvantages?
Doctor: Yes, there is a downside to stereotactic radiosurgery treatment. Occasionally the tumor begins to grow again. If the tumor does start growing at a later date, there would be more fibrous tissue and scarring in the area of the tumor because of the radiation. If we eventually had to remove the tumor surgically, the fibrous tissue and scarring would significantly increase the risk that your facial nerve would be damaged during the surgery.
Patient: So what are the general guidelines for when one has the surgery and for when one has the stereotactic radiosurgery treatment?
Doctor: In general, we consider the patient’s age and the tumor’s size. Usually, for patients who are approaching 60 years of age or greater and who may be in questionable health, either observation or stereotactic radiosurgery treatment would probably be a reasonable option. Observation is a good option for older patients, because the tumor may never get big enough to cause serious problems for the patient before the end of his or her life. The stereotactic radiosurgery procedure may, at the very least, inhibit growth of the tumor for at least 5 years. If the tumor starts to grow after that time period, we may be able to perform a repeat stereotactic radiosurgery treatment, or at that point, we can elect to monitor and track the tumor.
Patient: But I am 50, and my health is good overall.
Doctor: Yes. In healthier patients and patients who are under 60, the tumor will most likely start to cause problems if you just let it run its course without treatment. Surgery is a definitive way to remove the tumor in its entirety. Because your hearing is already gone, that eliminates one of the risks of surgery, which would be loss of hearing. There is also another reason to choose the open surgery for much younger patients. The long-term effects of radiation on benign tumors are not known. The stereotactic radiosurgery procedure may not be a wise choice in patients whose life expectancy is longer, because over time the radiation might result in a malignant transformation of the tumor or cause even another tumor to grow. The risk of this, of course, is small but there is a definite risk.
Patient: I think I understand the pros and cons of the treatment options. Considering everything, I think I would like to have the surgery. How do I arrange for that?
Doctor: Our nurse will coordinate that for you. Do you have any other questions?
Patient: Not at this time. Thank you, Doctor.
Doctor: You’re welcome.
Consultation For Meniere's Disease
This consultation is part of a series of consultations with Head and Neck Surgery specialists at the University of California, San Diego. The case is a hypothetical patient chosen to represent a composite of the usual and most common patients with this specific disorder. Where gender, age or race make a difference, these will be specifically cited. Where they do not make a difference, they may be omitted. The consultation is presented for purposes of general information. Specifics about an individual case and specific treatment must be discussed between the patient and the treating physician.
The patient is a 42-year-old female who was referred by her primary care physician with a diagnosis of Meniere’s disease.
Doctor: Good morning, and welcome to UCSD. I am Dr. Nguyen. What can I do for you today?
Patient: I really hope you can help me. My problems began about six months ago when I had a terrible attack of vertigo. I was at home watching the news, when all of a sudden there was high-pitched ringing in my right ear and the entire room began spinning. I was really scared. My husband took me in to the emergency room. Things slowly settled down over the following 2 hours, but I was still nauseous. The emergency room doctors gave me some medicines that helped with the nausea. They let me go home later that night, but I still had a lingering sensation of dizziness for the next 2 days.
Doctor: Was that the only episode?
Patient: I was okay for about two weeks, but then it happened again. I went up to my room and laid down until the spinning sensation quieted down. I was able to see my primary care doctor the next day, and he ordered some lab tests and an audiogram. He gave me a prescription for a medicine called Valium to take during the acute attacks and told me to avoid salty foods. I’ve been trying to follow his advice but it is not working. I have had two more vertigo spells since then; I've missed almost 3 weeks of work; and I am afraid to drive.
Doctor: Let me begin by asking a few more questions. Do you ever notice a sensation of fullness or pressure in your right ear?
Patient: Yes, I do!
Doctor: Do you have ringing in your ears?
Patient: I usually get some ringing in my right ear after the attacks, but it isn’t too bad right now.
Doctor: Do these attacks affect your hearing?
Patient: Yes. For a few days after the attacks, sound on the right is muffled; it seems to get a little better over time.
Doctor: Have you had pain or headaches associated with these attacks?
Doctor: Have you had ear infections or drainage from either of your ears?
Doctor: Have you ever had surgery on your ears?
Doctor: Do you take any medicines?
Patient: Just a Valium when I get an attack.
Doctor: I would like to take a look at your ear. (Doctor examines the patient's ears, looks at the ear drums, and checks the tuning fork tests.) Everything looks normal in your canal, ear drum and middle ear space. Your tuning fork tests indicate there is a slight sensorineural hearing loss on the right.
Doctor: It is likely your symptoms are caused by a condition we call Meniere’s disease. This is also known as endolymphatic hydrops. We have looked at the inner ears of patients with your symptoms and have found an enlargement of the endolymphatic space, one of the fluid-filled spaces in the inner ear. We don’t know what causes Meniere’s disease, but it seems that as the fluid accumulates in the inner ear, it can affect hearing and balance. The acute attacks may be caused by a tiny rupture in the membrane surrounding the endolymphatic space; and this causes the severe vertigo and hearing loss. With time, the hole seals off, and the ear makes a partial recovery. However, over the course of several years, the hearing and balance functions can become permanently damaged.
Patient: Is there anything we can do to confirm the diagnosis?
Doctor: Unfortunately, there isn’t a perfect test for Meniere’s disease, and we don’t have the ability yet to take pictures of the inner ear with enough detail to diagnose endolymphatic hydrops. We can, however, do some tests to look at your baseline hearing and balance function.
Patient: I would like to undergo those tests. What about in the meantime - - is there anything I can do?
Doctor: In addition to a low-salt diet, we usually recommend that patients take a low dose of a common blood pressure medication called hydrochlorothiazide (HCTZ). It affects the kidneys and promotes the elimination of salt from the body. It seems to reduce the frequency and severity of the attacks of vertigo, but may take up to 6 weeks work. I would be happy to prescribe it for you. You will need to take supplemental potassium and have your potassium levels checked periodically because this medication has the effect of lowering the body’s potassium levels.
Patient: Okay. I’ll start on the hydrochlorothiazide and get the audiology tests you suggested.
The patient returns 3 weeks later with the hearing and balance test results.
Doctor: Welcome back. How have you been?
Patient: I think I’m doing a little better. I haven’t had any of the really severe attacks; but I still have a little ringing and fullness in my right ear.
Doctor: Let me show you your audiogram. There is mild high-frequency sensorineural hearing loss on your right side, and your speech discrimination score is down a little bit. You balance tests indicate your right side is a little weaker, and the electrocochleography test is consistent with cochlear hydrops.
Patient: What is going to happen to me?
Doctor: The usual course of Meniere’s disease is progressive, but the frequency and severity of attacks tend to diminish with time. Up to 80% of patients progress to moderate sensorineural hearing loss. In as many as 40% of patients, this condition goes on to affect the other ear.
Patient: So what should I do now?
Doctor: Well, if you are holding up okay right now, you can stick with the hydrochlorothiazide and behavioral modifications. Things to try include a low-salt diet (less than 2 grams per day), avoiding excessive caffeine, smoking cessation, and incorporation of stress-reducing activities into your day. There are surgical options as well, but they are, of course, more invasive, and we should try the medical approach first.
Patient: Thank you for all the information. I’ll follow your advice and see how things go.
The patient calls the office 4 weeks later, in tears, having had another attack of dizziness. The nurse schedules another appointment with Dr. Harris.
Patient: I’m miserable. I thought I was getting better; but it happened again. This time I missed my son’s eighth grade graduation. What are the surgical options you offer for this problem?
Doctor: The simplest procedure is insertion of a pressure equalization tube. This may help by reducing the effects of pressure changes on the middle ear and subsequently the inner ear. This procedure also allows patients to try the Meniette device. It is a new device that you hold up to your ear canal. It produces controlled puffs of air designed to push some of the extra fluid out of the inner ear.
Doctor: A more involved procedure, called endolymphatic sac surgery, is designed to reduce the fluid in the endolymphatic space. This involves a mastoidectomy, where we drill into the bone behind the ear and place a small drain into the endolymphatic sac. This surgery has the advantage of hearing preservation, but it is more dangerous because we are operating close to the brain. Furthermore, we can’t guarantee this procedure will work in everyone.
Doctor: Another treatment that can preserve hearing and help some patients is the injection of medications directly into the middle ear space. We can inject steroids into the middle ear and allow them to diffuse across the round window into the inner ear. They may work by improving blood flow and reducing inflammation in the inner ear.
Doctor: Finally, there are destructive procedures with the purpose of disabling the balance system in the affected ear. These include chemical and surgical labyrinthectomy and vestibular nerve sectioning. These treatments provide the best relief from acute attacks of vertigo; but they can damage the residual hearing.
Patient: Which treatment do you recommend?
Doctor: I will be happy to explain in more detail the risks and benefits of the treatments we offer. Since you have functional hearing in your right ear, I would recommend starting with one of the options that will continue to preserve your hearing. Consider a pressure equalization tube and the Meniette device. Steroid injection is also a reasonable alternative. My goal is to allow you to make an informed and educated decision that you are comfortable with.
Consultation For Otosclerosis
This consultation is part of a series of consultations with Head and Neck Surgery specialists at the University of California, San Diego. The case is a hypothetical patient chosen to represent a composite of the usual and most common patients with this specific disorder. Where gender, age or race make a difference, these will be specifically cited. Where they do not make a difference, they may be omitted. The consultation is presented for purposes of general information. Specifics about an individual case and specific treatment must be discussed by the patient and the treating physician.
The patient is a 38-year-old female who was referred by her primary care physician for hearing loss.
Doctor: Good morning, I am Dr. Nguyen. What can I do for you today?
Patient: I am having increasing difficulty hearing conversations with my friends, and when talking on the telephone. I had my hearing checked by my primary care physician and he told me I had a conductive hearing loss.
Doctor: I would like to know more about the problems with your hearing. Are they predominantly on one side or the other?
Patient: I first had problems with my left ear about 5 years ago, and now my right ear is affected too. I decided to see if anything could be done about it because I use my right ear to talk on the phone; and I’m getting worried that I may be going deaf.
Doctor: Have you ever had ear infections?
Doctor: Do you having ringing in your ear?
Doctor: Do your ears ever drain fluid?
Doctor: Do you ever have dizzy spells or feel the illusion of motion when you know that you aren’t really moving?
Doctor: Has anyone in your family had hearing problems?
Patient: Actually, now that I think about it, my mother had a problem with her hearing bones [the ossicles]. She said the stirrup [stapes] was stuck and her doctor had to break it loose so that she could hear again. Do you think I could have the same problem?
Doctor: Some types of hearing loss can run in families. Looking at your hearing test, you have a symmetric conductive hearing loss of 30-40dB in both of your ears. When I perform the tuning fork test, your forks confirm the presence of a significant conductive hearing loss. Your clinical picture is very suggestive of a hereditary form of hearing loss called otosclerosis.
Patient: What is otosclerosis?
Doctor: Otosclerosis is a condition that affects the stapes footplate, the hearing bone that sits on the oval window, and transfers sound energy from the middle ear to the inner ear. In patient with otoscelosis, the stapes can become fixed to the oval window so it no longer vibrates smoothly, resulting in what we call a conductive hearing loss.
Patient: Are there any tests that can confirm the diagnosis?
Doctor: Excellent question, but no, there are no good tests for otosclerosis. Occasionally a high resolution temporal bone CT can help confirm the diagnosis, but the only way to know for sure is to perform a middle ear exploration and check the mobility of the stapes.
Patient: If you go in there and find out that the stapes is fixed, can you fix it at the same time?
Doctor: Yes. The procedure is called a stapedectomy, where we remove the suprastructure of the diseased stapes, and create a small hole in the middle of the foot plate. We then insert a prosthesis that functions as a new stapes and won’t fuse with the bone around the oval window.
Patient: What is the success rate of this procedure?
Doctor: This procedure closes the air-bone gap, improving your hearing over 90% of the time.
Patient: What are the risks?
Doctor: The most common risk is a change in the taste of the anterior third of your tongue; this is often temporary and can happen in up to a third of patients. This is caused by irritation or injury to a small nerve that runs directly under the eardrum. The other risks of ear surgery include bleeding, infection, and dizziness. Three fairly serious risks include facial weakness, hearing loss and severe dizziness. These happen less than 1% of the time.
Patient: How long does the surgery take, and will I need to stay in the hospital?
Doctor: The surgery takes 1-2 hours, and patients are able to go home the same day. It can be done under local anesthetic, and you will be awake to hear the results at the end of the procedure. We will then place packing in your ear; so do not be alarmed that you cannot hear very well the first week. We will remove the packing at your first post-operative visit. Expect to be a little dizzy the first day or two, and plan to have someone drive you to the hospital and home again after the procedure. You will receive antibiotics for one week, and pain medication, although pain is generally minimal.
Patient: Can I get both ears fixed at the same time?
Doctor: I recommend we do one ear first; and once it is healed and you are happy with the results, we can do the second ear 3-6 months later.
Patient: Do I have any alternatives?
Doctor: Yes, you may purchase hearing aids.
Patient: I feel like I am too young to be wearing hearing aids, and I can’t go in the water with them. Thank you for taking the time to explain everything to me. I would like to proceed with the surgery.
Doctor: Very well. My nurse will check with your insurance company to obtain approval and then find a date that will suit you.
Two weeks later the insurance company approves the stapedectomy. The patient is scheduled for surgery. One week prior to surgery the patient returns for a preoperative evaluation.
Doctor: Well, it looks like your insurance company has approved the surgery.
Patient: I am looking forward to getting this done.
Doctor: We will complete a history and physical at this visit, and give you a chance to meet your anesthesiologist.
Patient: What do I need to do before my surgery?
Doctor: You will need to stop all aspirin and non-steroidal anti-inflammatory medications, which include Motrin, 10 days before your surgery. Be sure not to eat or drink anything after midnight the night before your surgery. The anesthesiologist may let you take your blood pressure and heart medications with a small sip of water; but other than that, the morning of surgery you should not have any food or drink. Even when you brush your teeth, spit the water and the toothpaste out. If you do drink or eat, the anesthesiologist may postpone your surgery to another day.