Episode 112 – How EssilorLuxottica Is Fighting The Myopia Epidemic – Drs. Shalu Pal And Millicent Knight

Share Your Story

TTTP 112 | Myopia


Myopia has been described by many as a global epidemic. Some of the keenest minds in eyecare have made it their mission to help fight the progression of myopia across the globe. In this episode, Dr. Shalu Pal and Dr. Millicent Knight, two of the foremost experts in myopia, discuss how EssilorLuxottica is working to battle the myopia epidemic. Dr. Pal shares her perspective as a renowned clinical expert, and Dr. Knight explains how multiple industry partners are coming together in coalitions, such as GMAC, to combat the increase in myopia around the world. This is the first part of a three-part series in partnership with EssilorLuxottica. Dive into this episode, and let’s fight the myopia epidemic with Dr. Shalu Pal and Dr. Millicent Knight.

Leonardo Learning Platform – https://leonardo.essilorluxottica.com/landing
Global Myopia Awareness Coalition – https://www.myopiaawareness.org/

Watch the episode here


Listen to the podcast here



How EssilorLuxottica Is Fighting The Myopia Epidemic – Drs. Shalu Pal And Millicent Knight

Thank you so much for taking the time to read. I always appreciate taking your time away from your busy days and your schedules to learn and grow with me. I’m super excited. This episode is the first in a three-part series that we are doing on myopia management. Thanks to EssilorLuxottica for partnering and sponsoring this series of conversations.

Also, helping us bring on myopia management experts to help us all get better in this space and learn what’s new, what’s hot, and what we should be doing to make sure we’re serving our young patients at our best. I have two amazing guests, two people that I’ve been wanting to have on the show for so long, and I’m so glad I get to have them on. They are two of my favorites in the eyecare space, Dr. Shalu Pal and Dr. Millicent Knight. Thank you so much for coming on for this part one of this three-part series.

Thank you, Dr. Sian, for having us.

My pleasure. Let’s do a quick intro but if you want to share a little bit more about yourselves, you can do that as well. Dr. Shalu Pal is a practicing optometrist in the Greater Toronto area. She’s the owner of Dr. Shalu Pal and Associates, which is a big group practice. They have all the subspecialties under one roof. Dr. Pal herself specializes in myopia management, specialty contact lens, dry eye, and aesthetics. She’s also the co-editor of Mastering Myopia, which is a newsletter and myopia management. She’s part of a research group called Myopia in Practice. She is a super expert in the myopia management space. It’s always a pleasure to speak with you, Shalu, and learn from you. I’m happy to have you on.

Dr. Millicent Knight is the Senior Vice President of Medical and Professional Affairs of North America at EssilorLuxottica. She was previously the owner of North Shore Eye Center, which was a vision source practice, including myopia management care at her practice at that time. Dr. Knight is a legend in the eyecare industry and someone I’m sure you’re going to see around a lot if you haven’t already. Thank you again for joining us, Dr. Knight.

Thank you.

If there’s anything else you guys want to mention about yourselves, please feel free to but we’ll go through the conversation. Everybody who’s reading is going to understand pretty quickly how well-versed you guys are in myopia management and the level of expertise that you have in this space. It’s nice to bring these two perspectives, practicing clinical expertise from Dr. Pal and that industry and research insight from Dr. Knight in this conversation. Let’s start the conversation a little more broadly. There is a lot of conversation, noise, talk, and excitement about myopia. It’s an epidemic as we know. There are lots of changes happening in this space. From your span standpoint, Dr. Knight, where do you see EssilorLuxottica’s role in this space?

I’ve always been a patient care advocate first clinically in my practice. I’m proud to represent EssilorLuxottica in this space because it has also been a champion for many years. Essilor started in 1849, Essilor International. We’ve been in the eye care space for a long time. Essilor of the Americas started in 1972. Since that time, we’ve been a champion of all types of vision care issues but we’ve spent decades in research and development, specifically looking at ways to better manage myopia. We believe as a leader in this industry that that’s our responsibility and something that we take very seriously.

I also wanted to add to that note that in addition, we partner with eyecare providers all the time. One of the things that we believe with myopia control and myopia management is it’s an excellent opportunity for doctors and their teams to be able to be proactive in differentiating their practices in providing this type of care to the pediatric population, which sometimes is a bit overlooked.

We believe in comprehensive eye examinations as early as possible and managing those children in a regular cadence. We have access to the myopia expert. It’s a 700 series.  It’s a tool that can help with diagnosing myopia. We’ll talk a little bit more about this, I know but we’ve also brought to market the Stellest lenses, which have over 67% efficacy in controlling the progression of myopia compared to single-vision lenses when they’re worn for 12 hours a day. We’re super excited about that.

TTTP 112 | Myopia
Myopia: EssilorLuxottica has access to the myopia expert. It’s a 700 series and a tool that can help diagnose myopia.


I’m very excited. I spend quite a bit of time talking about myopia in the office and we lean into that in our practice, myopia management. I even give a cope approved lecture. I’m always shameless self-promotion all the time here. My lectures are called the myopia startup and the name gives it away. It’s a way to educate our colleagues and encourage them to get started in myopia management. I’m super excited about the fact that we have these tools available to us and treatment options that a few years ago we didn’t have. It’s a pretty cool time to be practicing optometry and specifically a cool time to be seeing our young patients and helping them the way we can.

I wanted to lean into that with Dr. Pal. What does that look like for you in your practice? What types of conversations are you having? At what point in the patient journey does a parent or a patient start to learn about myopia and the fact that there is myopia management available? If you wouldn’t mind, it’s a bit of an open-ended question but if you could walk us through, what does that look like for you?

I want to phrase this or put a bit of context on this. A lot of our colleagues who are reading are interested and perhaps are having the conversation but they’re not sure how to lean into it and bring it into their practice. I want to make sure we give them something very tangible to take out of this so that when they go back to work the next or the day after, they can say, “Here’s what I’m going to implement. 1, 2, 3.” Please take it from there.

Learning about myopia management starts in many different places and I believe it starts before patients even come into our office. Patients hear it from other parents that have their children in this program. It starts by word of mouth. We have the ability through our social media platforms and websites to start talking about myopia management. People are coming in asking about it.

Once in the office, there are many different methods that we employ to teach people about myopia management. One is I have a device that measures axial length and every trial habit done on them during their initial testing under the age of nineteen. I make it simple for my staff. I don’t have them think, “Is this a myope? Is this a hyperope? Do I need to do it or not?” It’s just a blanket all kids under the age of nineteen will have axial length done.

What that does is it sparks the question from parents, “What’s this new instrument? What are you doing that’s new?” The staff is prepared with conversation pieces to be able to say, “This is what’s going on. Dr. Pal will talk to you a little bit more about it when you’re in the exam room.” In the exam room, I talk about it to every expecting parent, whether they’re having a boy or a girl with myope or hyperope. I’m talking to grandparents or parents. I’m mentioning it to anyone that has access to children that need to be hearing about this.

Every myope that’s in the right age group, which is under 22, for me, I’m talking about myopia management to them. The conversation doesn’t have to be so big and grand. The conversation is about how incredible it is to be a myope in this age category because we can do something about it. We’ve got great tools at our disposal. In other places in the world, our colleagues down below in the US don’t have access to this. I feel so lucky to be able to have this as an option for my patients. For me, it’s a regular conversation that comes up so much of my day.

When I talk to our colleagues and my friends about this, the number one thing I say is, “Talk about it. Start the conversation.” It’s helping in multiple ways. You’re educating the parents about what’s available but for yourself as a practitioner, the more you talk about it, the more you can streamline that conversation and make it more succinct and effective.

I love the point about having the axial length because it’s more data points for us to measure potential change over time. It’s a solid, tangible thing to show a parent to say, “Look what we’re measuring. Here’s what it should be. Here’s what it is.” It’s a lot easier to understand that versus just verbalizing and trying to explain it to them. That’s great.

On that note, when you are speaking with a parent in the exam room, do you get a lot of skepticism? Any pushback on this topic? The idea of myopia management is pretty new for a lot of our patients. Do you get a pushback? How do you overcome that and help patients and parents understand the benefit?

To properly answer, I need to give you a little bit of history about my journey. I have been talking about myopia management for years. When I started my journey of learning, understanding, and diving, I’ve been fitting ortho-k lenses since 2004. It’s been a long time. This real deep dive into myopia management started over a decade ago. In the beginning, as I was learning, I was talking too much about studies and facts. Everything I was learning, I was sharing. I sat back and I’m like, “What am I doing? Am I trying to convince them or am I trying to convince myself that this is something good?”

As the conversations and things evolved, and I started to learn more and became a true believer in the power of myopia management, what we’re capable of doing, and how we can help people, my conversations changed. I stopped trying to convince them because I was different. It became, “You’re a myope. This is the standard of care. This is my recommendation for you as a myope. You’re a parent of a myope? This is what is best for your child.” There wasn’t this long conversation of, “Here’s what we used to do. Here’s what we do now. You get to choose. Here’s the price difference. This is the best recommendation I can give you.”

My decision-making process comes down to gathering the child and parents. Do we want to be looking at a strategy that involves contacts of the last? We’re lucky we have that option. We can have that. That’s what the conversation is about, which is what we always do. I give the best recommendation. For myope, it’s always going to be a myopia management strategy.

That confidence is part of the other thing. The more you talk about it, the more you understand. You get feedback from the parent about what’s landing, what’s not landing, and when it is too much information or not enough information. You can tailor that. Once you’ve seen that it works, you get that confidence in your mind that there’s no question. This is the path. I use that analogy with dry eye a lot but in myopia management, it’s the same thing. The parent feels that confidence.

You will have occasionally and it’s very occasional where you will have some parents that are like, “This is different than what we went through.” As kids and teenagers, it might not. We will talk a little bit more and some will want more research. I will present the data and show them it. I’ll say, “I can send you that stuff. I’ve got email templates ready to go. Here are the latest studies.” That’s not as often as it used to be because this is my normal practice where I would recommend a single vision with AR coding or the Stellest lens with our anti-reflective coding.

That’s going to come from speaking about it and getting hands-on experience with it, getting your hands in the mud so to speak. Let’s talk a little bit about the technology in that Stellest lens to give a bit of more in-depth background on it. The halt technology, if we can speak a little bit about that. Dr. Knight, if you wanted to speak to that, it’s up to you, or whoever wants to take that one.

Shalu, you can feel free to chime in. I would say though, to your previous comments, your patients and the parents trust you. If you have a good working relationship with them and you make a recommendation, often they’re willing to go along with that recommendation. You have to meet the patient where they are. To your point, there are going to be some who want more data. Fortunately, we have great data.


You have to meet the patient where they are.


We have published a three-year study in the American Academy of Ophthalmology Journal. We presented the four-year study results at ARVO. They’ve been very compelling. They’re digestible information. It’s not so convoluted that parents gloss over it but it gives them the important or pertinent information that they need to know to feel confident to move forward if they happen to be that more analytical type of patient or parent who needs to know more information. To your point, you need to meet them where they are.

The aspheric lenses that we have worked well. In most cases, as long as a child is wearing the glasses as they were prescribed. Our recommendation is for twelve hours a day as a full day. We’re getting the efficacy of almost a full diopter of slow-down in the progression of axial length, as well as over 67% reduction in the progression of myopia. It’s exciting results and consistent. One of the other key areas that we wanted to track is whether or not children, as they get older, the results remain steady and still work for them, and they do. That’s something that we can all be excited about when prescribing these lenses for those slightly older teenagers.

Shalu mentions that goes up to 22. To anybody under the age of 22, you’re considered as a potentially progressing myope.

My rationale behind that is when we think about LASIK and LASIK candidates, they don’t want to touch anyone under the age of 25. They want to wait until people have stopped progressing. That’s the age I’ve planted in my head. Until then, why are we not talking about it? We may not have the research behind those teenagers but we know that progression is still happening. With good deductive reasoning, it makes sense to me to continue the conversations a little bit longer.

We do want to generally stick to what’s been studied and what’s been written and proven so to speak, and peer-reviewed and all of that. We want to stick to that as our basis. I’ve used this for older teenagers as well and it makes sense. If they’re still progressing at 17 or 18 years old, we don’t just say, “You’re sixteen. We don’t care if you’re progressing anymore.” It doesn’t make any sense. We’re going to continue to try to do what we can to help. That’s the point. Get that there’s no scientific data to support that. That’s fine. Anecdotally, you, myself, and other colleagues I’ve spoken to have shared they’ve seen it’s been beneficial.

We’re not doing any harm. We’re giving them a better option than just a single-vision lens. When you have a seventeen-year-old that’s coming in nervous and that’s still progressing and saying, “Can I do something,” would you say no? Would you say, “Yeah, I have an option for you?” Sure, we don’t have the data to support it but it’s a better option than just giving a single vision product.

Even the children who were in the control group wearing single vision lenses, once they were changed into the whole lenses, they immediately saw great results too. We know it works and it works very effectively.

I’d like to zoom back out a little bit. We started a very broad global epidemic and we zoomed into clinical. Shalu gave us some insight into what’s happening in her practice. Let’s zoom back out. Global again, our broad view, you mentioned Dr. Knight, that Essilor is investing time, money, research, and other things. There are partnerships that have been developed. I’d like to learn a little bit more about that because it’s not just in the clinic here. We’re trying to create awareness globally for patients and ECPs alike. It’s a bit of a broad question but I’m specifically teeing you up to tell us a little bit about a very specific initiative here. I’d love for you to tell us about that, please.

Let me start first by saying that when you’re building a new category like this, myopias have been around for a long time but we haven’t had the tools available to be able to control it. When you’re building a new category, that’s not something usually that one company can do on their own. Sometimes it takes the commitment of a number of companies, associations, and other stakeholders working together to make that happen. You’ve got to start by building a runway. We started building the runway before we had a lens to take off but it was the right thing to do to start with educating the consumer and the patients about what was at risk and about this growing pandemic around this.

We have the data so it doesn’t make sense for us to not educate and do everything that we can to make sure that our patients are aware of the challenges that might face if we are, first of all, not committed to preventing and providing good recommendations that can help prevent the onset of myopia. Be able to manage its progression so that the child does not progress to the point later in life where we have diseases and eye diseases that are associated with longstanding progressive myopia. If we can prevent that, why wouldn’t we?

TTTP 112 | Myopia
Myopia: EssilorLuxottica has the data, so it makes sense for us to educate and do everything we can to ensure that our patients are aware of the challenges that might face them.


EssilorLuxottica was one of the earlier organizers. In particular, one organization is called the Global Myopia Awareness Coalition, affectionately called GMAC. What I’m impressed about that organization is it has thirteen companies along with associations throughout the industry, both in optometry and ophthalmology. We also have an advisory committee of key stakeholders, which include pediatricians, optometrists, ophthalmologists, nurses, school teachers, and everyone who can advise and make recommendations for that child.

We want to touch to make sure that we’re all working together, holding hands to build this category and make sure that we take care of the children the right way. The exciting thing about that is we’re focused on creative, energetic, influencing campaigns. We have one that’s going to be starting very shortly and rolling out both in the US and the Canadian markets.

We’ve done the research in both areas to make sure that we had a profound message that resonated with those stakeholders in the specific areas. We’ve had the support of the Canada Association of Optometry joining GMAC, which has been fantastic because they have helped us with being able to carve the messaging out to the Canadian population so that it has the stickiness that we’re looking for.

This has been an exciting initiative, being able to look at parent influencers. We have found that to be a very effective way of being able to share very natural content and good information in a way that people can consume it. We’ve also worked with pediatricians in this space and we’ll also continue to work with eyecare professional influencers to ensure that we have a messaging that resonates with everyone. We take advantage of every platform that we have available to do that as well. Dr. Pal had one of our influencer families in her office and practice. I’d love to hear more about how that went.

Dr. Knight, it was so much fun. They come in with their children. We had so much fun with them, teaching them about eye care, the importance of eye exams and children’s eye exams, and how vital good vision is to proper education and learning. We talked about myopia management, axial length, and in-depth about how myopia management spectacles and contact lenses function and create that parabolic shape on the retina.

We talked about it all. They loved the experience. We had so much fun with them in the office. It was a great time for everyone to learn about what’s new and what’s happening in the industry. They were amazed at how much the profession is progressing and what’s possible for their kids, which was not possible for them when they were younger.

It’s fantastic that the Canadian Association of Optometry, along with the World Council of Optometry, have established myopia control as a standard of care. We have all these resources available. When I first started managing these patients with myopia, we didn’t have the resources available. Now, we have tools, cool technology, great innovations, and everything that you need in that toolbox to be able to effectively manage these children. There is no reason for doctors to not be engaged in this area. We’re here to help in any way that we can at EssilorLuxottica.

While it’s still early stages of myopia management and building this up, it’s come along quickly and there are so many resources. Look into GMAC and the companies that are involved in that because all of those companies are going to be excited to provide us with the resources, education, and information you need to get more involved. It’s great that you mentioned ophthalmologists, pediatricians, and nurses are involved in that.

Every single time I give this lecture, the question I get at the end is, “What’s the conversation like with ophthalmologists?” There’s a gap there in what we are doing and what we want to do compared to what ophthalmology is doing. To have something that’s going to help to bridge that gap and make it so everybody’s on the same level as far as the conversation that is happening with the kids and their parents, that’s important.

With these thirteen companies and the in-kind contributions that we get from a lot of our key media companies, they have stepped up in a big way. We don’t talk about who you should see. Whether you see an optometrist, an ophthalmologist, or a pediatric ophthalmologist, we stay in a neutral space. Some of the companies are competitors. You just don’t see that in this industry with people working together like that. We’re all passionate about making sure that the patient is well taken care of and using all of our resources to make sure that we’re able to do that.


We’re all passionate about ensuring the patient is well taken care of and using all our resources.


We talk about making sure that the child gets in for an early as possible eye examination, an eye examination on a regular cadence, and a comprehensive eye examination. We want to make sure that even the parents have the tools to have the right discussion. That can also be challenging for parents when they don’t feel like they have the right verbiage to be able to articulate to the doctor what it is that they want to do. If you go to www.MyopiaAwareness.org, which is the GMAC website, we have talking points for the parents. They can download it, print it, take it in, and feel confident having that conversation with their doctors.

We all have this. We may not want to ask a question, the risk of sounding dumb or something like that. It’s nice to empower parents to give them that little bit of knowledge and confidence to ask the right questions and start the conversation.

Down the road, we want parents and the conversation that we might be having later or we’ve had but over the years, we’ve been talking about for a while from some of the research that we’ve done. Parents are not taking their children in to have eye examinations. They should be doing that before they start school. You don’t see the same thing with going to see the dentist or the pediatrician. Our aspiration is that placing value on the importance of eye care will be right up there with these other areas that are also super important.

The education of the public is extremely important. You’re right. There’s something that’s missing. Parents got to take their child to the doctor, pediatrician, or dentist. A lot of times, parents are not aware that an early eye exam is so important. We know the stats have been there forever. Eighty percent of our learning is through our vision. I don’t know if this is a Canadian stat but at least 25% of kids have some vision-related issue, which may affect their learning. That 25% is a lot of kids. How many times have we seen this?

When parents come in, they think that their child is doing fine visually. It’s tough to pick it up when the child is 3 or 4 years old and they may have a vision-related issue. When they come in, we uncover that and parents are often surprised that there is a problem there. It’s something that needs to be addressed. Building that overall awareness importance of the eye exam is very important as well.

We’re going to zoom back in real quick here. Remember, I was saying I want to have something tangible for our colleagues who are listening to take away from this to start to implement in their practice. I thought we could wrap up by sharing a couple of best practices in myopia management and implementing or prescribing spectacle lens options for our colleagues in their practices. Dr. Pal, I imagine this is going to be more your wheelhouse but if you don’t mind, maybe 2 or 3 things that you want to share with us that you think will help our colleagues to hit the ground running when they go back to work.

It is so important that you involve the child in the decision-making process. Parents may come in and know exactly what they want. I had a child whose parent was like, “We want ortho-k.” I looked at the child and she was terrified. She looked at me and I said, “What would you like to do?” She goes, “Dr. Pal, can I stay in my glasses?” I’m like, “You can.” I was able to bring that option to the parent and bridge the gap between the two. Involving the child is so important.

TTTP 112 | Myopia
Myopia: It is so important that you involve the child in the decision-making process. Parents may come in and know what they want but not what their kids want.


Your staff is vital in this process because they can help you with answering a lot of questions. This lens is so easy to fit. I do happy calls on all of my patients. Over the last few years, everyone that we have called has said, “I’m good. There has been no non-adept. We have had no issues.” Involving my staff in the process to make sure that they are helping in this is important. Remembering that it’s easy, it’s got great adaptation, and standard of care, and this should be standard of care. Start having the conversations.

I know we have axial length but when we started, we didn’t. We didn’t have the nice beautiful instrumentation we have now. We did develop and get the A-scan, which we were using to convince ourselves that it was worthwhile. From there, we moved up to the axial length measurement device we have. We didn’t start that way and you don’t have to start that way. You start by having the conversation, dive in, and educate yourself so you become a believer in the impact that we can have. We’re having a significant impact in improving the quality of life of our patients and realizing that we make a difference. This is one of the wonderful ways that we can do it.

That’s approachable advice. You’re not saying go invest in tens of thousands of dollars of equipment or anything. It’s all right there for us to do. For lack of a better term, it’s simple for us to do this, to have that conversation and start prescribing Stellest lens or whatever other modality you want to offer in your office. Thank you very much for sharing that. Dr. Knight, any final words that you’d like to share?

I started by talking about the strong commitment that EssilorLuxottica has had in this eyecare space, specifically around lenses. We will continue to bring compelling innovation to the marketplace in this space. I’m just putting that out there. We’re going to continue that journey because we’re here for the long haul in this area. We’ll continue to bring new technologies in the instrument space and anything that gives that wraparound support to the doctor and their full team because everyone on the team is important in being able to manage that.

We also have a learning management system, Leonardo, which also supports the doctors and is able to get their team and staff. I like to call them myopia champions, educated and feeling comfortable and confident, having those additional conversations that we know sometimes. After the parent leaves the doctor’s office, often they have other questions that come up in their minds or things that they may not have been comfortable asking the doctor. If you’ve got a good myopia champion, one of the staff members can take those questions on. That is the one area that directly supports the doctors and their teams.

The other thing that we’ll continue to do is support organizations, which we have happened from the very beginning. Organizations like the International Myopia Institute, which you developed a lot of the white papers that some of the clinical data come through. We’ve been able to extrapolate to help come up with some of the clinical guidelines for being able to manage myopia.

Also, Myopia Profile. We partnered with them with the learning management system I spoke about with Leonardo, being able to continually train staff so that they feel comfortable and confident, and being able to help the doctor manage those patients effectively. That’s our commitment. We’re here for the long haul and anything that we can do to support the patient’s journey, we’re here to do that.


We’re here for the long haul, and anything that we can do to support the patient’s journey, we’re here to do that.


Thank you for giving us those opportunities and innovations. Dr. Sian and I couldn’t do what we do to the level that we do without the innovation that’s brought to us. Thank you.

Thank you, Dr. Pal. We have that continued commitment from us.

Shalu, any final words of wisdom before we wrap up?

You got to dive in and start. We have myopes in our chairs. You just have to start the conversations and get over that hump of, “How do I do this?” There are so many tools out there. You’ve already mentioned so many. You don’t have to build anything. Everything is there for you. Every resource that you need to give a parent, it’s already built for you. You need to start having conversations, trusting the work that’s been done already, trusting that this is the right thing, and proving it to yourself. Dive in and make this truly standard of care for your practice.

The phrase “standard of care” is important for us to imprint in our brains. You look at a child differently. Every time you see that child, you’re like, “I have to look at this child and treat this child differently than I have in the past.”

You should be looking at the parents and grandparents differently too. Looking at, Dr. Pal’s comments, she has started having that conversation with everyone. Teachers, nurses, you have them sitting in your chair every single day. Ask mothers, fathers, and grandparents about it. Grandparents are big advocates. They’re making sure that their grandkids get in. You have the audience. They’re sitting in your chair every single day. Take the opportunity to educate them.

Thank you so much both of you, Dr. Knight and Dr. Pal, for joining me in this conversation. I appreciate it. Honestly, you two are my favorite people in the eyecare space so to have you both on at the same time is a real pleasure and honor. Thank you for coming on. Thank you to EssilorLuxottica for partnering on this three-part series. This is part number one of this three-part series of conversations on myopia management.

We’ll be bringing in different experts for each conversation to help us along in our journey as ECPs to improve the way that we treat our young patients. Make sure you stay tuned for all three parts. They’ll be coming out pretty close together. Thanks again for joining me here on the show. I will see you very soon in the next episode.


Important Links

What I’ve Been up to Lately

Let’s Connect

instagram facebook facebook2 pinterest twitter google-plus google linkedin2 yelp youtube phone location calendar share2 link star-full star star-half chevron-right chevron-left chevron-down chevron-up envelope fax