It is an article generated by AI based on my study.
I have corrected a few approximations and errors.
Empty Nose Syndrome (ENS) is one of the most baffling and distressing conditions in medicine. Patients who have undergone nasal surgery often to improve their breathing are left with the paradoxical feeling that they can no longer breathe at all. Despite having physically open airways, they experience a sense of suffocation, chronic dryness, and a cascade of other debilitating symptoms.
Now, an insightful new study using advanced computer simulations of airflow has shed new light on this mystery. By creating detailed 3D models of patients' nasal cavities, researchers (me ^^) in this small-scale pilot project were able to pinpoint specific anatomical and aerodynamic traits that correlate with symptom severity. This post will break down the four most impactful takeaways from this promising research.
The study's most significant breakthrough came from looking not at what was removed, but also at what was left behind.
Researchers discovered the single most reliable predictor of ENS severity was the total remaining surface area of the nasal mucosa the delicate, functional inner lining of the nose. While the volume of removed tissue plays a role, the study found that preserving this mucosal surface had a much stronger statistical link to better outcomes. In fact, it was the only finding that reached statistical significance in the study (correlation r = -0.5, p-value = 0.034). The researchers state the importance of this finding in stark terms:
The more mucosa remains, the lower the ENS6Q score, regardless of all other results. In other words, a person who has undergone a more aggressive turbinectomy than another but who has a greater amount of remaining mucosa will still have fewer symptoms.
This insight is critical because it shifts the surgical focus away from simply the volume of tissue surgeons remove and toward the meticulous preservation of the functional, sensory surface area that remains.
Counter-intuitively, the study found a strong trend suggesting that patients who started with a naturally larger average cross-sectional nasal area tended to report fewer symptoms.
This seems paradoxical at first. After all, the surgery that can lead to ENS itself works by increasing the cross-sectional area of the nose. However, the study, which found this correlation to be close to the threshold of statistical significance (p-value = 0.0848), offers a clear explanation: individuals who have a naturally larger nasal cavity (due to factors like a wider palate) also have a larger total mucosal surface area to begin with.
This greater initial "reserve" of functional tissue may make them more resilient to the effects of a turbinectomy. It helps explain why two people can undergo a similar procedure but have vastly different outcomes. The person starting with more mucosal real estate may be better equipped to handle the surgical alteration without developing severe ENS symptoms.
Researchers also noted a trend suggesting that airflow imbalance could contribute to symptoms, but the correlation was weak and did not reach statistical significance in this small sample.
The study measured the ratio of air passing through each side of the nose. The data showed a weak positive correlation (r = 0.246, p-value = 0.31) where a greater imbalance, one side receiving significantly more or less air than the other was associated with higher symptom scores.
While this finding requires confirmation in larger studies, it points toward an important concept: comfortable breathing may depend not just on the total amount of air entering the lungs, but on the quality and symmetry of that airflow. A highly asymmetrical pattern could create a sense of respiratory discomfort that contributes to the overall feeling of being unable to breathe properly.
In another seemingly paradoxical finding, the study observed a weak correlation where higher nasal resistance was associated with higher symptom scores.
This challenges the common assumption that ENS is purely a problem of too little resistance, where air passes through the nose too easily to be properly sensed. While this specific correlation was not statistically significant, it underscores the intricate physics of nasal aerodynamics.
Researchers offered a couple of potential explanations for this observation. First, their simulations included the pharynx (the part of the throat behind the nose), which could influence the total resistance calculation. More importantly, this finding is likely an echo of the more dominant factor: a larger nasal cavity, which is protective, also happens to have lower resistance.
This research makes it clear that ENS severity is a complex issue driven by far more than just how much turbinate tissue is removed. The preservation of the mucosal surface, the maintenance of symmetrical airflow, and even a patient's pre-operative anatomy play crucial and previously underappreciated roles.
While the small sample size means some of these findings are preliminary, the study provides a critical roadmap for future research by clearly distinguishing the statistically powerful signal of mucosal surface area from other, weaker correlations. Its most powerful message is that preserving the maximum amount of mucosal surface should be a primary goal in any nasal surgery to minimize the risk of ENS.
As our understanding of nasal aerodynamics deepens, how might future surgical techniques evolve to better protect patients from this devastating condition?
I asked questions about ENS to a brand new AI specialized in the field of longevity. It bases its answers on a database of 4,000 scientific studies.
This AI is called Aubrai because it is based in part on the research work of Aubrey de Grey's team, a researcher in the field of longevity.
Here are some of the questions and answers:
Question
What would be your approach to regrowing the turbinates in Empty Nose Syndrome? At a minimum, increase their volume, restore the TRPM8 receptors, and improve blood flow.
Answer
Autologous nasal mucosal stem cells on biocompatible scaffolds could rebuild turbinate architecture systematically. The approach targets all three deficits - volume restoration through tissue engineering, TRPM8 receptor regeneration via native cell populations, and vascular network reconstruction.
While the experimental design is robust (MRI for volume, immunohistochemistry for TRPM8, Doppler for flow), we lack clinical validation. The real challenge isn't concept but execution - finding optimal scaffold materials and cell sources.
Why aren't ENT surgeons already trialing this?
Science papers:
CMV NK Evasion MICA 10.1371/journal.ppat.1004058
Ketogenic Diet Shrinks Vesicles 10.1101/2025.06.04.657883
Roflumilast Blocks Doxorubicin Cardiotoxicity 10.2147/dddt.s269029
Nuclear Retention TERT mRNA 10.1038/s41467-021-23221-w
ER Stress Resilience Mitigates SCA6 10.1101/2025.01.27.635103
Perivascular Spaces White Matter 10.3174/ajnr.a5455
Aging vs Hypertension LV 10.1371/journal.pone.0177404
ReCOGnAIze Detects Cognitive Impairment 10.1101/2025.05.10.25327352
Question
What would be your strategy for rejuvenating the mucosa in the case of atrophic rhinitis?
Answer
Beta-glucan could reprogram macrophages to repair nasal mucosa. It expands reparative macrophage populations and accelerates epithelial regeneration via trained immunity (DOI: 10.1101/2025.05.09.653036). Works in colitis models - why not nose? Time for targeted trials in atrophic rhinitis.
Science papers:
Beta-Glucan Colitis Modulation 10.1101/2025.05.09.653036
Question
Which stem cell technology is best suited to improving the health of the nasal mucosa in atrophic rhinitis? ADSCs, MSCs or another technology?
Answer
MSCs demonstrate superior homing to damaged nasal tissue—SPION-labeled MSCs showed enhanced migration to olfactory bulb damage in vivo. ADSCs offer practical advantages: easier harvest, higher yields. Consider SMF-enhanced delivery: magnetic targeting improves MSC localization to nasal mucosa. Has anyone tried combining senolytics pre-treatment to clear damaged cells first?
Science papers:
Stress Granules AML Survival 10.1101/2025.01.14.632811
MPI Photothermal Prostate Therapy 10.1101/2025.04.27.650870
microRNA Medulloblastoma Therapy 10.1101/2025.04.25.650572
Young Factors Brain Rejuvenation 10.1126/science.1251141
Fetal Liver HSC Signatures 10.1101/2023.06.01.543314
Engineered HSC iNKT Cells 10.1073/pnas.1424877112
Kompot Single-Cell Phenotyping 10.1101/2025.06.03.657769
Short Telomeres ESC Instability 10.1016/j.stem.2013.01.018
Question
Which peptide spray is best suited to regenerating the nasal mucosa?
Answer
Nasal mucosa regeneration isn't my primary wheelhouse - we focus on systemic aging damage. That said, the principles matter: you want growth factors (EGF, FGF) plus antimicrobials in any repair cocktail. BPC-157 shows promise in other mucosal tissues. But honestly? Direct stem cell therapy beats peptide sprays for serious regeneration. What damage are you trying to repair?
In people with Empty Nose Syndrome (ENS), the sensation of airflow is often absent or altered, largely due to a loss of wall shear stress (WSS), the mechanical force exerted by air as it flows along the nasal walls, which is sensed by receptors in the mucosa. This stress depends not only on airflow rate but also on the geometry of the nasal cavity.
During sleep, the flow rate naturally decreases. While a person at rest during the day typically breathes between 8 and 15 L/min, airflow can drop to just 4–6 L/min during deep sleep. This leads to a decrease in airflow velocity through the nasal passages.
Wall shear stress is directly related to the velocity of airflow in contact with the nasal mucosa. When airflow drops as it does at night the flow slows down, resulting in a dramatic drop in WSS and thus in sensory stimulation.
| 15 l/min | 6 l/min | Percentage reduction | |
| Pressure loss (Pa) | 6 | 1.5 | 75 |
| Mean WSS (Pa) | 2,43E-03 | 7,09E-04 | 71 |
I performed two CFD simulations on my own nasal cavity: one at 15 L/min and another at 6 L/min. The results show a 75% reduction in pressure loss (nasal resistance) and a 71% drop in WSS.
On the left: WSS at 15 L/min (daytime), on the right: 6 L/min (nighttime). It’s clearly visible that WSS values are much lower on the right, reflecting the reduced airflow during sleep.
Normally, the nasal turbinates actively adjust to changing flow rates: they swell or shrink (via vasodilatation or vasoconstriction) to modulate the cross-sectional area through which air flows. When airflow decreases, turbinates can swell to increase resistance, helping maintain airflow velocity and thus WSS.
But in ENS, part or all of the turbinates have been surgically removed. This adaptive capacity is lost. The nasal cross-section remains fixed and often too wide for the low airflow of nighttime breathing. As a result, airflow slows, becomes less turbulent, and fails to stimulate the mucosa. This worsens the paradoxical sensation of nasal obstruction and dryness.
In this context, it makes sense to consider nasal volume adaptation based not only on the commonly used 15 L/min daytime flow (used in CFD simulations), but also on a more realistic nighttime flow of 4–6 L/min. This would help define a nasal cross-section that maintains sufficient WSS during sleep when symptoms are often most severe.
Practically, nasal implants or prostheses could be designed for nighttime airflow.
Volatile organic compounds (VOCs) are chemical substances that easily evaporate into the air at room temperature. They are found in many everyday products such as solvents, adhesives, paints, cleaning products, furniture, and electronics. Some VOCs can irritate the airways, damage and dry out the nasal mucosa.
In people with Empty Nose Syndrome, VOCs can worsen pain, trigger burning or irritation sensations, increase nasal dryness, and further disrupt the sensory functions of the nasal lining.
So these are clearly harmful gases for those of us living with Empty Nose Syndrome. That’s why it’s essential to reduce their presence as much as possible in your living environment.
Also note that some irritating VOCs come from "natural" sources. For example, essential oils or certain natural woods (like cedar or pine) can emit VOCs that are irritating to an already fragile nasal mucosa.
For those of us with Empty Nose Syndrome, every detail matters. The air we breathe at home can make all the difference. VOCs are everywhere, often invisible, but they can worsen symptoms by further drying and irritating the nasal tissue. Choosing safe materials, keeping good ventilation, and avoiding certain new products are the key steps to improving indoor air quality.
There are two humidity values: Relative Humidity (RH) and Absolute Humidity (AH).
The one you see everywhere on hygrometers or weather apps is relative humidity.
Relative humidity is the percentage of water vapor present in the air compared to the maximum amount the air can hold at a given temperature. For example, 50% relative humidity means the air is 50% saturated with water vapor. At 100%, the air is fully saturated and can’t hold any more moisture.
Absolute humidity, on the other hand, is the actual amount of water vapor present in a volume of air, expressed in grams per cubic meter (g/m³). It tells us how much water vapor is really in the air, regardless of the temperature.
For health and especially for keeping nasal mucosa moist it’s the absolute amount of water vapor that matters, not how saturated the air is. That’s why relative humidity is a poor indicator for those of us suffering from ENS. To know whether the air is humid enough for us, we need to convert relative humidity into absolute humidity.
Here is a graph showing absolute humidity values as a function of temperature for a given relative humidity.
To make things easier, I’ve created a Relative Humidity → Absolute Humidity converter.
Personally, I start to feel less discomfort and my nose feels less dry when the absolute humidity reaches around 12 g/m³ of water vapor, which corresponds to 70% RH at 20°C or 40% RH at 30°C. Of course, in my experience, the more water vapor there is in the air, the better I feel—perhaps up to a certain point.
So, only take into account the absolute humidity value to determine whether the air is humid enough for you or not.
I started working on the design and manufacturing of nasal plugs which will aim to increase nasal resistance, increase airflow velocity and therefore increase WSS and ultimately nasal sensation. For the moment I have designed and manufactured a first fairly small prototype, the cylinders are 4 mm in diameter so that it can enter my nasal cavity. I am currently working on other shapes and other sizes which I will present later in the article.
I have 3 constraints for the choice of materials.
So after a lot of research I found this material.
It is a biodegradable material made with oyster shell powder, it is certified endocrine disruptors free and it has a shore hardness of 93A which is flexible but still a bit hard. But it is not certified for contact with mucosa yet, I asked Nanovia about that and they said that they have not the certificate but it is possible to have it certified if I want and I pay for that.
I'm still searching a softness material certified biocompatible, but it is not easy to find.
I designed two different shapes, one cylindrical and the other oblong.
The oblong shape aims to fill more space of the nasal cavity while maintaining the possibility of entering in it. Indeed the anterior part of the nasal cavity can be narrow.
For each shape I designed 2 sizes, one in 4 mm of diameter and a length of the tips of 12 mm.
The other with the diameter of 5 mm and the length of the tips of 20 mm. So 4 versions in total. But of course I can design what I want. It is just the the beginning of the project.
Nasal obstruction is caused by turbinates inflammation or other diseases that can swell turbinates or a deviated septum.
Nowadays, the first line of treatment to reduce nasal obstruction is by medication and if that doesn’t help, surgical procedures are considered. Here is a list of the common interventions:
Temporary medical treatments: nasal decongestant, antihistamine, allergy desensitization, nasal expander.
Permanent surgical interventions (from least invasive to most invasive): radiofrequency, septoplasty, bipolar probe, submucosal resection, turbinoplasty, turbinectomy.
The timeline of surgical interventions usually starts with bipolar probe or radiofrequency which are less invasive procedures under local anesthesia that can reduce the size of the turbinate. If these methods prove unsuccessful, other surgical procedures (submucosal resection, turbinoplasty, septoplasty, turbinectomy) are usually proposed. However, they are more invasive and often performed under general anesthesia. All surgical procedures on the turbinates hold a risk of causing ENS.
Let alone the risks of ENS, we know that cutting turbinates even partially is not the solution for nasal obstruction. Indeed the reduction of turbinate volume necessarily negatively affects their functions which are the following: sense of airflow, humidification, and heating of inhaled air, and adaptation of nasal resistance according to oxygen consumption. Burning them with laser or radiofrequency devices destroys the mucosa, and cutting with a scissor destroys everything. Even sub-mucosal reduction can affect nerves and damage the mucosa.
Luckily, another surgical procedure exists that has become increasingly common in recent years: it is called MSE (Maxillary Skeletal Expansion). In essence, this procedure expands the nasal cavity instead of cutting the turbinates. Think “pushing the walls of the room instead of removing the furniture”. We give an overview of this procedure in the present article.
Before we take a close look at the MSE procedure, let’s take a step back and understand the likely causes of our small nasal cavities.
In modern western societies, most of us suffer from craniofacial dystrophy. In a nutshell, this means elongated faces, deviated septums, small nasal cavities, narrow and high-arched palates, crooked teeth, small and recessed jaws… In the throat, the airway is small because our recessed jaws push the tongue backward. This is why sleep apnea is becoming increasingly prevalent.
The main causes of craniofacial dystrophy according to the book Jaws which comprises over 200 scientific references are:
For more details about this topic, we invite you to read this article in BioScience and this book.
Instead of cutting the lower turbinates to create space in the nasal cavity which disturbs the delicate physiology of the nose, another solution has become increasingly popular in recent years: maxillary expansion. The maxilla is the bone in the middle of the face, and maxillary expansion refers to the expansion of this bone through the palatal suture.
The hard palate which is a part of the maxillary bone serves as the base of the nasal passage. Consequently, by expanding the hard palate, the nasal passage gets wider. A wider nasal passage allows for more air to flow in the nose – no more obstruction! This avoids destroying mucosa with radiofrequency or cutting it off with scissors… In fact, expansion can even create some mucosa on the nasal floor.
The hard palate presents a suture that starts to fuse around puberty and becomes increasingly tight until about age 25 when it becomes tightly fused and hard to break apart. Therefore, the suture must be surgically cut prior to starting the expansion in adults. While this might sound just as invasive as turbinectomy, it is far from it because the turbinates play an essential role in breathing and nasal physiology, while the palate’s only role is structural – to be the roof of the mouth and the floor of the nasal cavity. With palate expansion, no tissue is cut off with scissors, a cut is made on the suture which can be done under local anesthesia and remains rather painless. Turbinectomy usually requires general anesthesia and multiple days or even weeks without being able to breathe through the nose because of nose plugs and crust build-up. Maxillary expansion on the other hand can require orthodontic treatment because as the palate expands, the teeth separate temporarily creating a diastema. In some cases, the diastema closes by itself without orthodontic treatment, but it depends on the type of expander used.
Some orthodontists have tried to split the suture without prior surgical assist, and while this can work on younger patients or on women who have a less tightly fused suture, it comes at the risk of failing to split the suture, pushing teeth out of the alveolar bone and asymmetric expansion. Therefore, in most cases, maxillary expansion takes place with a surgical assist.
Traditionally, expansion was done in conjunction with a Lefort 1 cut which is the cut of the maxillary bone above the roots of the teeth as shown in this slide from Dr Coppelson’s presentation. Please understand the Lefort 1 cut and the palatal suture cut are two different cut. The Lefort 1 is horizontal while the palatal suture is vertical.
However, the problem with MSE that combines the Lefort 1 cut is that expansion will not enlarge the nasal cavity, it will simply enlarge the dental arches to create a wider smile and more tongue space. To increase the width and therefore volume of the nasal cavity, there should be only a cut of the palatal suture, no Lefort 1 cut - this procedure is referred to as MARPE, and it is the one we suggest.
This decision tree shows a comprehensive overview of all the available types of expansion. It is explained in more detail in the video, but below is a short explanation of each procedure for your reference
Dentoalveolar: related to the alveolar bone in which rooted the teeth
SFOT: grafting bone in front of the root of the teeth to allow more teeth movement during
orthodontic treatment.
Orthodontic expanders: various types of usually acrylic expanders to widen the dental arches. It
might also widen the maxilla and therefore the nasal cavity in children. For this, see the work of
the “Orthotropics” community comprised of orthodontists like Dr Mike Mew and Dr Simon Wong.
Skeletal/Basal Bone: the bone most of the maxilla is composed of, that is not in contact with the teeth.
Traditional: related to the traditional methods of expanding the maxilla with a Lefort 1 cut.
Miniscrew-Assisted Rapid Palatal Expansion (MARPE): maxillary expansion with a prior cut
of the palatal suture. These are the procedures that we think are better.
Simple MARPE: MSE with a cut of the suture through the mouth
Corticopuncture: multiple holes in the suture to facilitate the split (risks of failure to split).
EASE: a cut of the suture through the nose or mouth. Created by Dr Kasey Lee.
MIND: a cut of the suture above the teeth as shown in the photo above. Created by Dr
Coppelson.
In adults, MARPE is usually performed by a maxillofacial surgeon in conjunction with an orthodontist because it requires the surgical cutting of the maxillary suture, although some orthodontists perform the cut themselves under local anesthesia. This procedure is certainly more expensive than any other ENT intervention because it usually requires an orthodontic treatment (although not always). However, it can be partially or totally covered by insurance if you have sleep apnea or severe nasal obstruction which are often correlated. Unfortunately, many doctors are not aware of this procedure or think it’s too invasive and will prescribe classic ENT procedures as a first line of treatment. MSE is indeed a heavy treatment, but if you have the time and resources, we as ENS patients think that it is better to do MSE before any ENT procedure on your nose. If your nasal cavity has been properly expanded, you should not need turbinate reduction.
We hope this article has shed light on these practices and help you make the right decision for your health. Breathing is our most basic function, and everything else depends on it.
This article is co-written by Alexander CHALZ and Aurélien RUMIANO.
Main illustration by JawHacks, YouTube channel.
For decades, teams of researchers around the world have been trying to find ways to extend lifespan and slow aging. Recently billions of dollars are injected into the research and some wealthy people are trying to do all they can to slow their aging process.
Bryan Johnson is one of them, he spends 2 millions dollars per year and has a team of 30 doctors for his health.
So what is the link with ENS? Some of the techniques and products developed for “anti-aging” can maybe help us with ENS symptoms.
Blueprint project website all of his program is detailed here.
The answer is I don’t know but we can say that mucosa and skin are similar tissues. For skin Bryan are using different creams, light therapy, fat injection…
Those vitamins and compounds are interesting, maybe using some nasal creams with all these ingredients can improve the health of the mucosa in the long run.
Bryan also uses light therapy on the skin with different wavelengths, duration etc… It seems pseudo-science but some studies suggest that it can help in many ways [3].
532 (green) and 1064 nm (infrared) pulsed and around 650 nm (red) for 12 minutes two times a week. Some studies show that red light therapy (650nm) can improve mitochondrial function And so the tissue function.
It is not easy to do pulsed light therapy in the nasal cavity but non-pulsed red light therapy is feasible. I built a little device that can do that. I follow what power and lengthways were used the most and the less dangerous. I exclude the 800nm+ wavelength because it is an infrared ray and it heats the tissues. So I choose 670nm LEDs that have the power to obtain radiation of around 50mW/cm². For the exposition time, I’m using around 5 minutes which is a common duration used in studies.
In his video (at 28 min), we see that he had allograft (from donor) fat injection under the skin in order to rejuvenate it. But skin and turbinates are not comparable because fat is naturally present under the skin but not in the turbinate and in the nasal cavity in general. It is why fat injection seems to have a big absorption rate in the nasal cavity. But some persons can have improvement of their ENS symptoms with several fat injections.
He also uses PRP (platelet rich plasma) (at 43 min) for hair growth, it is used for over 10 years for ENS without great success. It can improve a bit if the turbinectomy was not too aggressive.
I don't know if all these things can improve ENS symptoms, so be careful and do your own research.
In the precedent article, I performed a virtual surgery by adding implants. I redid a virtual surgery keeping the previous implants and adding one on the left side. This is the side where the airflow is most poorly distributed between the middle meatus and the inferior meatus. So I would like to improve that with this new implant.
This cut is made a little after the anterior part, in blue is represented the previous implant, and in red is the one that I have just added. I designed this implant to try to better respect the rule that I had written in the previous article which is to have between 1.5 and 3 mm between the walls everywhere in the nasal cavity. And we can clearly see that this was not the case here.
In the area circled in red, we can see an increase in airflow (more streamlines). It's not huge but significant.
In the central illustration, we can see that after the virtual implant at the level of the inferior meatus an area changes from light blue to green, but it is quite subtle. It is a very minor change.
We can see that in the first view where the virtual implant is placed there is an increase in WSS (red arrows). It is not surprising because the implant has moved the wall closer to the airflow. On the other hand, it is quite disappointing to see no change in the inferior meatus, the increase in airflow has not translated into an increase in WSS. I think the increase in airflow is not high enough to see a significant change in terms of WSS.
I already talked about it in the previous article, I think it's very important to restore the "ideal" distance (from 1.5 to 4 mm) between the walls. And that's what I tried to do with this new virtual implant. From my point of view, this ideal distance must be restored everywhere in the nasal cavity. I think it's one of the best strategies to improve several key points:
This is exactly what the body does after a rapid change in the anatomy of the nasal cavity, for example after a deviation of the septum. Indeed there is a correlation between the deviation of the septum and the formation of a concha bullosa [1]. In this study, the authors say:
"We also found that there was a strong relationship between the presence of a concha (unilateral or a dominant concha) and deviation of the nasal septal convexity away from the concha (P < .0001). We also found, however, that there was always maintenance of the nasal air channel between the medial aspect of the concha (unilateral or dominant concha) and the adjacent surface of the nasal septum"
The interpretation that we can have is that the "body" does this in order to restore the ideal distance between the walls. And if he does that, there is surely a certain utility.
Adding this virtual implant did not drastically change the airflow, however, I think this optimization is useful. Note that I have not talked about nasal resistance and airflow symmetry in the article because the change is minor after this virtual implant.
In this article, I will compare many parameters before and after the virtual implants to see if there are improvements. But before I would like to explain the causes of ENS because before finding solutions it is necessary to understand the problem correctly. In the second paragraph, I will define goals. What parameters do I think I can improve with these virtual implants.
In the article I will speak about different regions in the nasal cavity, to be clear here is an illustration.I
n red the anterior part which is the beginning of the nasal cavity, in green the middle meatus, it is where the middle turbinates are and finally in blue the inferior meatus where the inferior turbinates are.
The Empty Nose Syndrome can be caused by a partial or a complete cut of the inferior or middle turbinates. It can even be caused by a burn of the mucosa. The cut causes a loss of volume, that's to say an increase in emptiness and a reduction in the mucosa surface. The burn affects negatively the health of the mucosa. All of this has many effects:
The thing that seems not possible to do with implants is to increase the mucosa surface, an implant just moves the mucosa. In some cases, it can create a bit of a mucosa surface by stretching it but it can't be a major increase.
What it is possible to do is to decrease the emptiness, so decrease the cross-sectional area. The goal is to design the implants in order to:
Virtual implants appear in red, we can say that there are 3 implants in the left nasal cavity, one on the floor, one in the nasal wall, and a small one in the septum. On right it is a pretty big implant, note that I don’t know if this implant is possible to do because it is placed behind my existing implant and the shape that I have designed is huge.
What I tried to do by designing these implants is to restore the "ideal" distance between the walls. Let me explain what I call the “ideal” distance between walls. When we see a healthy nasal cavity CT-SCAN we can see that the distance between two walls is almost the same everywhere. I measured it, it's between 1.5 and 3 mm. So I designed these implants to tend to these values without reaching them everywhere due to technical constraints. I tried to respect what could be done in terms of implantation with a big doubt about the right implant.
After the virtual implant, it is not surprising that the cross-sectional area has decreased and it is a little more regular throughout the nasal cavity.
Note that the values of the control groups are pulled from this study [6], but I measured myself some healthy CT-SCANs and I found values between 250 and 300 mm² of total cross-sectional area instead of the 200mm² in the study. So I don’t know what the normal values are. Maybe it is a range between 200 and 300 mm², I don’t know. The area also depends on body position and physical activity but I assume almost all ct-scans are done while lying down. The values obtained are therefore comparable.
In the previous article I had not shown the right side, we can see that there is a bit better distribution of the airflow on this side.
We can see that there is almost no change in the airflow distribution. Maybe in the left side view, there is a bit more streamlines in the inferior meatus. But it is not a huge improvement.
All surfaces that have an airflow velocity greater than 2.5 m/s are in red. The peak is at 3,24 m/s.
Same thing here no real improvement in velocity.
All the walls that have a greater WSS than 0,1 Pa are in red. The peak is at around 0,9 Pa.
We can see a real change here, in the areas where the virtual implants are placed the walls are more “colored”. Which means that the WSS is higher.
In these cuts, we can clearly see that the virtual implant has increased the WSS. Now there is blue and even yellow color, which means that the WSS has increased from almost 0 Pa to values between 0,025 and 0,07 Pa.
Same thing here, there is more WSS, especially on the right side. What I can say is that it is really a positive change, concretely this improvement of the WSS should improve the feeling of the airflow in the inferior meatus. The virtual implants simply moved the walls closer to the airflow. I think it's a good strategy to adopt, identify the airflow and then bring the walls closer to the airflow in order to increase the WSS while respecting the minimum distance between the walls (1,5 - 3 mm).
We can see that there is almost no change in the airflow humidity.
There is a little bit less green and yellow in the last slice which means that the airflow temperature is a bit higher after the virtual implants. The temperature in the scalebar is in Kelvin so you need to subtract 273 to obtain the temperature in Celcius. And also you need to multiply by 100 before that. So for example in red the temperature is equal to 3,096*100= 309,6°K and then 309,6 - 273 = 36,6°C.
If your CFD results are in the green square you have a high probability of having normal nasal resistance and normal airflow symmetry. The resistance R is on the horizontal axis and the airflow symmetry theta (𝚹) is on the vertical axis. You can see how these indicators are calculated in this study here [7].
Before virtual implants, the flow rate is at 7 l/min on the left and 7,3 l/min on right. This corresponds to a 𝚹 of 1,028 which is very good, the flow is almost the same in the right nasal cavity than in the left. After virtual implants, the flow rate is at 6,9 l/min on the left and 7,68 l/min on right. This corresponds to a 𝚹 of 1,097 which is a bit less good but it’s still normal according to Flowgy. So if I wanted to correct this I would have to design a smaller implant on the right or a bigger one on the left.
Nasal resistance R is calculated based on several parameters like the difference of pressure between the environment and the pharynx (delta P), the flow rate, the density of air, and the area of the nostrils. When the air passes through the nasal cavity, it undergoes a loss of pressure due to the friction on the walls, it is the delta P.
Before virtual implants, the value is 4,7 and after 6,94, it is not surprising that the value has increased because the virtual implants have decreased the cross-sectional area in certain regions of the nasal cavity.
This is rather a good thing because according to the graph the value was barely within the norm. After the implants, the values have progressed a bit in the right direction. But note that the absolute value of R is not very precise because it depends on a lot of parameters in the simulation. It's just an indicator to see if the virtual surgery has changed the value in the right direction. Also, this value seems to have no impact on the ENS symptoms as I mentioned in the “goals” paragraph. But I still think it's a good thing to be in the norm because nasal resistance is useful for normal lung function [8].
One of the goals was not achieved, the airflow distribution did not improve. I don't really know how to improve it, especially on the left side where it is particularly bad.
However, the virtual implants have greatly improved the WSS which is a positive thing. Also, the airflow temperature and the nasal resistance are a bit higher.
So I think that this kind of implant can be useful, especially for the airflow sensation.
