The sinuses, these unknown

June 15, 2016

Dr. Martin Desrosiers is an otolaryngologist at the Hôtel-Dieu campus of the University of Montreal Hospital Center. He works in collaboration with pneumologists at the Cystic Fibrosis Clinic to treat patients with sinus problems.

Can you briefly describe to us the role and function of the sinuses?

One of the problems with sinus pathology in general, not only related to cystic fibrosis, is that despite a good knowledge of the anatomy of the sinuses, the role they play in the body is little known. In general, we know that the nose conditions the air to present it to the lungs, so it heats it up, humidifies it, removes unwanted particles, offers a certain defense function and ensures olfaction. However, the role of the sinuses themselves remains unknown. Some hypotheses suggest that they could serve as insulators, protecting the brain from changes in outside temperatures. They could also offer a protection zone against facial trauma, lighten the head or allow it to float, or even serve as a basin for mucus production. However, when there are several hypotheses, it is rare that only one is valid.

What are the different types of sinuses?

With one exception, sinuses are double structures; there are four types: the maxillary sinuses, located in the cheeks, the frontal sinuses in the forehead, and two other lesser-known types, namely the ethmoid sinuses, located between the two eyes, and the sphenoid sinus, which is located in the middle of the head.

There are two types of sinus problems in patients with cystic fibrosis: infection and polyps. What is the difference?

First, we don't know which of these two problems — infection or polyps — comes first. In cystic fibrosis, there is a defect in the CFTR gene which is associated first with inflammation and then with bacterial colonization in Staphylococcus aureus and/or at Pseudomonas. We don't know how cystic fibrosis progresses in the sinuses, but since the sinuses and lower respiratory tract share the same respiratory membrane, it's likely to be a similar phenomenon. We suspect that there is an initial inflammatory attack that interferes with the normal defense mechanisms of the sinuses, which allows, or even facilitates, bacterial colonization. We find in the sinuses the same thing as in the lungs: an initial attack with the Staphylococcus aureus, and then with the Pseudomonas. Once installed on colonized mucous membranes, the bacterium does not invade the sinus to the point of destroying it or producing sepsis, but by the production and development of toxins and by an interaction between the respiratory mucosa and the bacteria, it will increase the inflammatory response and produce the changes associated with chronic sinusitis, which is very often inherent in cystic fibrosis.

As for polyps, whose macroscopic appearance is similar to a grape whose skin has been removed, they have a gelatinous, relatively soft appearance. In the so-called “normal” population, nasal polyposis is mainly found in asthmatics. In the latter, it differs from chronic sinusitis. Patients have symptoms related to sinus blockage by polyps but few pain symptoms due to the infection. Polyps in cystic fibrosis patients seem to be of a different type. They are linked to neutrophils, cells associated with infection, and not to eosinophils, cells associated with inflammation, as is the case in asthmatics. It should also be noted that although 95% of adults with cystic fibrosis suffer from chronic sinusitis in adulthood, only half of them will have nasal polyps.

What kind of problems do nasal polyps cause?

Sinus disease similar to cystic fibrosis can cause pain, nasal congestion, and purulent secretions that fall into the back of the throat, which can even leave the impression of a foreign body. The presence of nasal polyps is always complementary to chronic sinusitis in patients with cystic fibrosis, and it seems to contribute to symptoms by worsening the nasal obstruction problem. However, the problem of persistent sinus infection is still present as well and is part of the obstructive problem.

Can you describe to us what sinus surgery you perform for cystic fibrosis patients consists of?

Our goals

The purpose of this surgery is to open the natural holes in the sinuses and thus facilitate the drainage of secretions, while allowing better ventilation. In addition, washes with salt water or antibiotics will be more effective after the procedure because the fluids will penetrate deeper into the affected sinuses. In their normal, preoperative state, sinus openings are very narrow and easily blocked. In patients with cystic fibrosis, the sinuses are completely blocked, making any exchange with the outside impossible, thus preventing air or medication from entering. The secretions remain trapped inside, creating an environment conducive to infection.

The intervention

The intervention begins with an evaluation in an outpatient clinic and with a CT Scan of the patient's sinuses which will identify their particular anatomy and the sites of blockage. Then, either under local anesthesia with intravenous sedation or under general anesthesia, depending on the patient's choice and the extent of the pathology, we introduce a small specialized camera, similar to a telescope, inside the nose. Passing through the nasal passages, we look at the internal structures shown in magnification on a television screen, which provides excellent visualization. Then, again going through the inside of the nose, we use a variety of specialized instruments that will allow both to remove the polyps and to open and enlarge the passages leading to the sinus cavities. The procedure lasts on average between 40 and 60 minutes.

Postoperative steps

After the operation, once the nasal passages are unblocked, we leave in place two small catheters, the size of which is equivalent to a “Jelco” for intravenous solution. These are placed at the time of surgery and will then be used to irrigate the sinuses with antibiotics for seven days. Upon waking up, patients may also have a tamponade in the nose that stops the bleeding and that will be removed the same day or the day after the procedure in order to minimize the duration of the nose blockage. The surgery leaves no trace in the face because we go through the inside of the nose. It does not leave bruises around the eyes and is not particularly painful.

After a week of irrigations with antibiotics and salt water, the catheters are removed and the patient will undergo weekly cleanings at the outpatient clinic while the sinuses heal (3 to 5 weeks). Our experience prompted us to recommend regular sinus washes at home to prevent stagnant secretions inside the sinuses. This is comparable to respiratory physiotherapy, which clears secretions in the lungs. Given the simplicity of this procedure and the benefits it seems to bring to patients, we recommend sinus irrigation on a regular basis. Certainly, patients with cystic fibrosis already devote a great deal of time to their medical care on a daily basis, not to mention the frequent hospitalizations and numerous medical consultations. So we hesitate before adding an extra task to this busy routine. However, the ideal would be rinsing with salt water 2 to 3 times a day. The future will make it possible to determine which methods are the most effective and the least burdensome for patients. We also recommend the daily use of a topical corticosteroid. However, the use of the latter is not based on studies as scientific as for allergies, polyposis or asthma. But because of its low toxicity and the absence of side effects, we do not hesitate to recommend its use. During the postoperative period, patients are also treated with an oral antibiotic. In addition, due to the lung problems of patients with cystic fibrosis, we expect the date of the intervention to be performed at times of optimal lung health, which ideally coincides with the end of a course of intravenous antibiotics.

Does this intervention involve certain risks?

The procedure consists of going up to the outer walls of the sinuses, located on each side of the bone that separates the sinus from the eyes, and at the top, against the bone that separates the sinus from the brain. So it is a fairly delicate region. Any sinus intervention involves risks both for the orbital cavity, for the fibrous envelope that surrounds the brain and for the brain itself. At the level of the orbital cavity, complications can be manifested by a simple “black eye” or by more severe bleeding that can, in an extreme case, compromise vision. At the level of the brain, a tear in the fibrous envelope that protects it could occur, allowing the cerebrospinal fluid in which it bathes to flow. This would then require immediate repair at the time of surgery. However, these complications are rare. It should also be said that complications are less frequent when the surgeon performing the technique is very experienced. For this reason, we tend to refer patients with complex sinus diseases to specialized centers, where the risk of surgical complications is lower and where pulmonologists and otolaryngologists work together.

Do you prefer general anesthesia for this procedure?

Two factors influence the decision to operate under general or local anesthesia: the degree of nervousness of the patient and the extent of his sinus disease. An intervention lasting 40 to 60 minutes requires a certain amount of collaboration on the part of the patient. For those who are fearful or do not believe they are able to cooperate, we recommend general anesthesia from the start. We also prefer it in cases where sinus disease is extensive or if one or more sinus surgeries have taken place previously, as this may result in more time-consuming surgery. We understand more extensive diseases not because of the fear of not being able to provide the patient with sufficient anesthesia but rather because of the increased risk of bleeding, which would be less well tolerated by a patient with a more limited lung reserve. To proceed under local anesthesia only, it must therefore be a calm patient with limited sinus disease.

Does removing the polyps complicate the procedure?

The presence of polyps always makes surgery a bit more difficult: the risks of bleeding at the time of the operation being higher, general anesthesia is necessary.

However, with the motorized instrumentation that we currently have, the treatment of polyposis, while presenting fewer difficulties for the surgeon, is now much simpler and much more effective. However, this instrumentation has only been available for the last five years.

Previously, sinuses were neglected in the treatment of cystic fibrosis. Does considering them now have beneficial effects on the general health of patients?

Historically, sinus treatment, not only in cystic fibrosis but in the general population, was relatively unsatisfactory. Instrumentation was limited, as were the radiological means to look inside the sinuses. It was only in the mid-1980s that scanners were used and that new techniques for looking inside the sinuses were developed. These two technological breakthroughs have opened the way for new surgical procedures. In the general population, this has made it possible to develop surgical procedures that are both less aggressive and much more effective.

However, while the surgical treatment of sinus pathology alone, especially with regard to cystic fibrosis, was initially a bit disappointing, the situation has now changed. In experiments conducted at Stanford and San Diego, California, in the early 90s, doctors combined surgery with postoperative topical antibiotics. The results were convincing and led to significant improvements. As a result, the number of patients requiring multiple surgeries has declined significantly. We do not yet have local studies, so we must rely on the ones mentioned above. With regard to the relationship between sinus treatment and the general health of patients with cystic fibrosis, definitive studies evaluating the impact of sinus surgery on lung deterioration remain to be carried out.

Based on your own experience, do you believe that this surgery can have some influence on patients' lung deterioration?

Instead, we should take this problem backwards. In patients with cystic fibrosis who have a marked or rapid deterioration in their lung condition, we have the impression that the treatment of sinus pathology decreases the number of infections and could contribute to the spacing of hospitalizations, or even to reduce the speed of lung deterioration. It should be noted that for the moment, we have limited ourselves to intervening in patients who are particularly symptomatic in terms of the sinuses, and therefore in the “seriously ill”. It is obvious that within this population of more affected patients, success is more difficult to achieve. It would be very interesting to treat sinus disease in all cystic fibrosis patients, even those with no symptoms yet, before lung damage develops. With this in mind, we are now intervening systematically in patients who will have to undergo a lung transplant, i.e. in patients who have sinus disease that is often asymptomatic. For them, we succeed in maintaining the sinuses in a healthy state on endoscopic examination, and in maintaining the health of the upper respiratory tract after a lung transplant. We suspect that this may help prevent or reduce bacterial colonization in the lungs after a lung transplant. Unfortunately, this has never been studied prospectively, as the number of patients undergoing transplants is limited for a given center. So we have to rely on our own experience. Obviously, it would be very interesting to join forces with other lung transplant centers to carry out such a study.

How can we explain that for some patients, the benefits of surgery are only of short duration?

Obviously, surgery does not correct the initial defect of cystic fibrosis. What you need to understand is that it is only part of the treatment for sinus disease. It is therefore necessary to consider surgical treatment as one therapy among others. Ideally, surgical therapy should be followed by intensive medical therapy. For now, unfortunately, the patients who have sinus surgery are the most severely affected patients. They are more likely to come back due to several factors: persistent bacterial colonization, a persistent state of inflammation, a recurrence of polyps, a blockage of sinus holes as well as uncontrolled healing. This highlights the importance of post-operative medical treatment; we need to emphasize that. Also, and very unfortunately, patients who have had multiple surgeries before often have healing problems that have developed as a result of these numerous surgeries. This will make both surgery and healing more difficult, and therefore reduce the chances of a successful procedure.

Cystic fibrosis patients frequently suffer from headaches. Is this frequently due to sinus pathology?

It is true that we frequently see headaches in patients with cystic fibrosis. However, these headaches can be multifactorial. As in the general population, spinal problems (which can manifest as headaches), migraine tendencies and, especially in patients with cystic fibrosis, nocturnal hypoxia (a desaturation of the oxygen level), which is manifested by headaches upon waking up, should be considered. So the headache does not necessarily come from the sinuses. We are wary and hesitant before immediately attributing headaches to a sinus problem. For example, many cystic fibrosis patients with headaches will complain of frontal pain. However, strangely enough, their CT shows that the frontal sinuses are not even present, as they did not develop during youth. Sinuses may actually be the cause of headaches but they are not the cause of All headaches: caution is required when making a diagnosis. It should be noted that when the headache is indeed due to the sinuses, surgery often improves this problem.

Thanks, Dr. Desrosiers.

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