The potency Units of BOTOX (onabotulinumtoxinA) for injection are specific to the preparation and assay method utilized. They are not interchangeable with other preparations of botulinum toxin products and, therefore, units of biological activity of BOTOX cannot be compared to nor converted into units of any other botulinum toxin products assessed with any other specific assay method [see WARNINGS AND PRECAUTIONS and DESCRIPTION] .
“A younger face has a heart shape, and an older face is a little more bottom-heavy and square,” says Dr. Matarasso. “But if you put toxin in both sides, you are not reducing the movement of the muscle, you are thinning the muscle out a bit. You can restore a youthful look. It’s not as dramatic or quick-acting as other areas, but it can be a nice way to improve the contour of the face.”
Ptosis generally occurs from injecting the frontalis incorrectly. The worst mistake is for the injector to move the procerus and corrugator injection points higher, where they will place more onabotulinumtoxinA into the frontalis. It is important to examine patients to determine their preexisting conditions prior to treatment administration. In particular, patients should be examined for pre-existing eyelid ptosis or pseudoptosis. With pseudoptosis, the lid strength is normal, but soft tissue covers part of the upper lid. With lid ptosis, the lid strength is weak. For both lid ptosis and pseudoptosis, patients will have frontalis compensatory activity, resulting in upgoing eyebrows (reverse Babinski sign). With brow ptosis, the frontalis is weak, and the eyebrow is depressed downward leading to tissue resting on the upper lid. To avoid this, the frontalis should be injected in the upper third of the forehead. The corrugator muscle attaches to bone at the medial end of the superciliary arch. The muscle fibers travel laterally and upward inserting into the skin in the middle of the supraorbital margin. The corrugator muscle is partially blended with the orbicularis oculi and occipitofrontalis. The supraorbital and supratrochlear nerves pass through the corrugator muscle. The corrugator muscle acts to pull the eyebrows downward and medially, which causes vertical wrinkle lines in the skin between the brows.

But it could be something else altogether. In 2008, Matteo Caleo, a researcher at the Italian National Research Council's Institute of Neuroscience in Pisa, published a controversial study showing that when he injected the muscles of rats with Botox, he found evidence of the drug in the brain stem. He also injected Botox into one side of the brain in mice and found that it spread to the opposite side. That suggested the toxin could access the nervous system and the brain.
Botulinum toxin (BTX) is a neurotoxic protein produced by the bacterium Clostridium botulinum and related species.[1] It prevents the release of the neurotransmitter acetylcholine from axon endings at the neuromuscular junction and thus causes flaccid paralysis. Infection with the bacterium causes the disease botulism. The toxin is also used commercially in medicine, cosmetics and research.
A recent encounter with one of my headache patients got me thinking. I am treating this young woman for chronic migraine with BOTOX injections. She told me that one of her other physicians had been surprised to hear about this use for onabotulinumtoxin A. According to my patient, the gastroenterologist’s words were, “BOTOX for migraines? I’ve never heard of that.” 

Botulism toxins are produced by bacteria of the genus Clostridium, namely Clostridium botulinum, C. butyricum, C. baratii and C. argentinense,[70] which are widely distributed, including in soil and dust. As well, the bacteria can be found inside homes on floors, carpet, and countertops even after cleaning.[citation needed] Some food products such as honey can contain amounts of the bacteria.[citation needed]
Injections: They're a popular topic and yet still shrouded in mystery and a veritable amount of secrecy. Most of us venture to a consultation or decide against them without actually knowing much information—how much they cost, what to expect during an appointment, or what the results will be. Because we're not willing to openly and freely discuss it (or have been taught not to), more often than not these conversations occur through a series of unanswered questions. Like sexual education, relying on abstinence is never going to be enough. We want to feel confident, look good, and make our own choices, and as such, that often leads to investing in modern skincare techniques.
We charge Botox Cosmetic by the area. The three most common areas are the crow's feet, forehead, and the lines in-between the brows (glabella). I typically use approximately 60 units for those 3 areas and charge $575. So in our practice we charge about $10/unit. I personally do all of my own injections and have treated over 2000 patients last year with Botox. I have considered raising prices over the past few years, but in today's financial turmoil, even though surgical prices have risen in my practice, Botox and other injectible prices have remained the same for the past 4 years.

Investors have been unhappy with Allergan's stock performance over the last year, and some have expressed interest in seeing the pharma company explore splitting up. On Wednesday, Allergan announced it plans to sell its women's health and infectious disease businesses. The news sent Allergan's stock down 2%, suggesting the move didn't go as far as some would like.
Botox injections work by weakening or paralyzing certain muscles or by blocking certain nerves. The effects last about three to twelve months, depending on what you are treating. The most common side effects are pain, swelling, or bruising at the injection site. You could also have flu-like symptoms, headache, and upset stomach. Injections in the face may also cause temporary drooping eyelids. You should not use Botox if you are pregnant or breastfeeding.
Our advice: if you’re going to try it, don’t give up on Botox for Migraine after the first try, and reconsider whether you’re a good candidate after three tries. Both Drs. Jackson and Kornel noted that there was a large placebo effect seen in many of the studies. “It’s hard to know if most of the benefit was from the drug or from the placebo effect,” said Jackson, who added, “but, patients don’t care if it’s a placebo effect.”
Program Terms, Conditions, and Eligibility Criteria: 1. This offer is good for use only with a valid prescription for BOTOX® (onabotulinumtoxinA). 2. Based on insurance coverage, Chronic Migraine patients can receive up to $700 off per treatment for up to 5 treatments in 2018. All treatments must be received during 2018. Maximum savings limit of $3500 per year for people with Chronic Migraine applies; patient out-of-pocket expense may vary. 3. This offer is not valid for use by patients enrolled in Medicare, Medicaid, or other federal or state programs (including any state pharmaceutical assistance programs), or private indemnity or HMO insurance plans that reimburse you for the entire cost of your prescription drugs. Patients may not use this offer if they are Medicare-eligible and enrolled in an employer-sponsored health plan or prescription drug benefit program for retirees. This offer is not valid for cash-paying patients. 4. This offer is valid for up to 5 treatments per year. Offer applies only to treatment received before the program expires on 12/31/18. 5. Offer is valid only for BOTOX® and BOTOX® treatment-related costs not covered by insurance. 6. A BOTOX® Savings Program check will be provided upon approval of a claim. The claim must be submitted with treatment details from an Explanation of Benefits (EOB) or a Specialty Pharmacy Provider (SPP) receipt. (If the BOTOX® prescription was filled by a Specialty Pharmacy Provider, both EOB and SPP details must be provided.) All claims must be submitted within 90 days of the date of EOB receipt. You may be required to provide a copy of your EOB or SPP receipt for your claim to be approved. 7. A BOTOX® Savings Program check may be sent either directly to you or to your selected healthcare provider who provided treatment. For payment to be made directly to your healthcare provider, you must authorize an assignment of benefit during each claim submission. You are not obligated to assign your BOTOX® Savings Program benefit to your healthcare provider to participate in the program. 8. Allergan reserves the right to rescind, revoke, or amend this offer without notice. 9. Offer good only in the USA, including Puerto Rico, at participating retail locations. 10. Void where prohibited by law, taxed, or restricted. 11. This offer is not health insurance.12. By participating in the BOTOX® Savings Program, you acknowledge that you are an eligible patient and that you understand and agree to comply with the terms and conditions of this offer.
“I don’t think it is physically addictive,” says Dr. Matarasso. “But, I have to be very frank with you, when I get a new patient I tell them (and I say this tongue-in-cheek) this product is truly addictive. I make jokes with my patients that we need a 12-step program for it, because when it’s done correctly, it’s a very simple office procedure, with impressive cosmetic results.”

"I have treated people with profound migraine headaches and it turns them right off," says Dr. Matarasso. "If you feel it coming on, it stops it, reducing the severity as well as the duration. I had a patient [who was] in college who had unremitting migraine headaches. She changed her diet, she changed her birth-control pill, she had acupuncture. I finally said to the mother, 'We need to try Botox,' and it has been a complete life-changing event for this woman."
Don’t be a pill. You're more likely to get a bruise at the site of the needle injection if you're taking aspirin or ibuprofen; these medications thin the blood and increase bleeding which causes the bruise. Skip the pills for two weeks in advance of your treatment. You should also tell your doctor -- before treatment -- about any supplements you're taking, even if they're "natural," because some (such as fish oil pills, gingko, or vitamin E) also thin blood. Your doctor may ask you not to use those supplements for two weeks before your treatment.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.
In both studies, significant improvements compared to placebo in the primary efficacy variable of change from baseline in wee kly frequency of incontinence episodes were observed for BOTOX (200 Units) at the primary efficacy time point at week 6. Increases in maximum cystometric capacity and reductions in maximum detrusor pressure during the first involuntary detrusor contraction we re also observed. These primary and secondary endpoints are shown in Tables 21 and 22, and Figures 7 and 8.
In 1820, Justinus Kerner, a small-town German medical officer and romantic poet, gave the first complete description of clinical botulism based on extensive clinical observations of so-called “sausage poisoning”.[37] Following experiments on animals and on himself, he concluded that the toxin acts by interrupting signal transmission in the somatic and autonomic motor systems, without affecting sensory signals or mental functions. He observed that the toxin develops under anaerobic conditions, and can be lethal in minute doses.[38] His prescience in suggesting that the toxin might be used therapeutically earned him recognition as the pioneer of modern botulinum toxin therapy.[39]
So what exactly are you putting into your face? John Paul Tutela, MD, a board certified plastic surgeon, explains, “Botox is a cosmetic injectable neurotoxin that is a very diluted form of Botulinum Toxin, which is found in the bacteria Clostridium botulinum. In this diluted format, it is used to relax your muscles—typically in your forehead, in between your eyebrows, and around your eyes.” The idea is that if you temporarily block local nerve impulses to specific muscles within your face, you won’t make certain facial expressions, so you won’t form the wrinkles that come with them, explains dermatologist Tsippora Shainhouse, MD, FAAD. These are the 7 signs you’re ready for Botox? (And 6 signs you aren’t.)
In the event of overdose, antitoxin raised against botulinum toxin is available from the Centers for Disease Control and Preventio n (CDC) in Atlanta, GA. However, the antitoxin will not reverse any botulinum toxin-induced effects already apparent by the time of antitoxin administration. In the event of suspected or actual cases of botulinum toxin poisoning, please contact your local o r state Health Department to process a request for antitoxin through the CDC. If you do not receive a response within 30 minutes, please contact the CDC directly at 1-770-488-7100. More information can be obtained at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5232a8.htm.
The seven toxin types (A-G) have different tertiary structures and sequence differences.[35][36] While the different toxin types all target members of the SNARE family, different toxin types target different SNARE family members.[34] The A, B, and E serotypes cause human botulism, with the activities of types A and B enduring longest in vivo (from several weeks to months).[35]
Botulinum toxin exerts its effect by cleaving key proteins required for nerve activation. First, the toxin binds specifically to nerves which use the neurotransmitter acetylcholine. Once bound to the nerve terminal, the neuron takes up the toxin into a vesicle. As the vesicle moves farther into the cell, it acidifies, activating a portion of the toxin which triggers it to push across the vesicle membrane and into the cell cytoplasm.[1] Once inside the cytoplasm, the toxin cleaves SNARE proteins preventing the cell from releasing vesicles of neurotransmitter. This stops nerve signaling, leading to paralysis.[1]

After the injection moves from the dermis and into the desired muscle, the nerves there are blocked—rather, their synapses, are blocked—by the Botox. So even though your brain my fire and signal for your body to move a particular muscle, Botox effectively blocks that firing and keeps the muscle from moving. The injected muscle can no longer contract, which causes the wrinkles to relax and soften, and also helps prevent new ones from forming.


The cost of Botox can range in price based on a number of factors. To help you understand how much a Botox treatment will cost you in NYC. I have created a complete Botox guide that will help you understand everything that must be considered when evaluating the procedure. Here you can obtain the basic information you need to make an informed decision before you get a Botox treatment. Along with learning about the differential cost of Botox, I will also briefly give you an overview of the reasons to consider a Botox treatment, and how you can maintain its beneficial effects.
BOTOX increases the incidence of urinary tract infection [see ADVERSE REACTIONS]. Clinical trials for overactive bladder excluded patients with more than 2 UTIs in the past 6 months and those taking antibiotics chronically due to recurrent UTIs. Use of BOTOX for the treatment of overactive bladder in such patients and in patients with multiple recurrent UTIs during t reatment should only be considered when the benefit is likely to outweigh the potential risk.
The use of Botox for migraines was, like many other new applications for the drug, a kind of happy accident. A Beverly Hills plastic surgeon observed that people who got Botox for wrinkles were reporting fewer headaches, paving the way for studies about migraines. Similarly, doctors in Europe were intrigued when they noticed that their patients who got Botox for facial spasms were sweating less than usual.
In just over a decade, the number of people in the U.S. receiving cosmetic botulinum toxin type A injections--mostly from Botox but also from another brand called Dysport, which commands less than 10% of the market--exploded. From 2000 to 2015, use of the toxins for wrinkles increased 759%. It became a cultural phenomenon too, spawning Botox parties, Simpsons jokes, even greeting cards. In 2008, Sex and the City character Samantha famously quipped, "I don't really believe in marriage. Now Botox, on the other hand, that works every time."
Botox is an injectable drug made from a toxic bacterium called Clostridium botulinum. When you eat the toxin produced by this bacterium, it causes a life-threatening form of food poisoning, known as botulism. But when you inject it into your body, it causes different symptoms. It blocks certain chemical signals from your nerves, causing temporary paralysis of your muscles.
What are Botox costs and benefits? Hands down, one of the most exciting cosmetic procedures in dermatology is Botox. It’s been over a decade that this miracle injectable has been approved for cosmetic use and the effects have been amazing. With one injection, Botox has the ability to iron out wrinkles and even prevent new ones from forming. Botox is completely safe and the perfect alternative to plastic surgery. Botox has even been shown to lift moods. A recent study showed that Botox had the ability to improve symptoms of depression when injected in the area in between and directly above the eyebrows. Other areas that can be treated with Botox are the crow’s feet, the upper forehead and around the hairline, to give the entire top half of the face a lift. Plus even more good news for Botox users! A new study shows that Botox injections not only get rid of wrinkles, but also make the overlying skin look and feel younger. So that means the overall appearance of your skin will look rejuvenated thanks to Botox injections. While the cost of Botox injections is certainly not cheap, it’s a sure thing and will produce real results that you can be happy with .
Many people who experience excessive sweating, whether on their hands, hairline, or even under their breasts or butt, are turning to Botox and other neuromodulators (like Xeomin or Dysport). "They help prevent excessive sweating by acting on the sweat glands directly," says NYC board-certified plastic surgeon Z. Paul Lorenc, MD. "The neuromodulator is injected into the sweat glands to relax the muscle and help combat excessive sweating."
In 1986, Oculinum Inc, Scott's micromanufacturer and distributor of botulinum toxin, was unable to obtain product liability insurance, and could no longer supply the drug. As supplies became exhausted, patients who had come to rely on periodic injections became desperate. For 4 months, as liability issues were resolved, American blepharospasm patients traveled to Canadian eye centers for their injections.[48]
It’s important to set up reasonable expectations for your Botox experience. “Botox does not get rid of all wrinkles on your face—it gets rid of wrinkles made from expressions,” Dr. Waibel explains. “It improves the appearance of these wrinkles by relaxing the muscles. It does not get rid of what we call static wrinkles—the ones that are seen at rest when looking in the mirror.” If those wrinkles bother you, talk to your dermatologist about the laser treatments that can help smooth them out. Find out the 13 craziest requests plastic surgeons have received.
BOTOX® is the brand name of a toxin produced by the bacterium Clostridium botulinum. In large amounts, this toxin can cause a form of muscle paralysis known as botulism, which is usually associated with food poisoning. Even though one of the most serious complications of botulism is paralysis, scientists have discovered a way to use it to human advantage. Small, diluted (weakened) amounts can be directly injected into specific muscles, causing controlled relaxation of the muscles.
In order to minimize the chance of developing a bruise, the key thing to prep for your injections should be to stop all blood thinners (like aspirin, Advil, Motrin, fish oil ,omega 3  vitamin E and other product) prior to making an appointment for an injection. Staying off blood thinners for at least one week is ideal but chilling the skin prior to treatment will reduce the chances of a bruise.

Andrew M. Blumenfeld is director of The Headache Center of Southern California. Most of his research has focused on the use of OnabotulinumtoxinA in the treatment of chronic migraine. He helped develop the injection paradigm approved by the United States Food and Drug Administration and has taught providers around the world on practical aspects of this treatment option.
Exploratory analyses of this study suggested that the majority of patients who had shown a beneficial response by week 6 had returned to their baseline status by 3 months after treatment. Exploratory analyses of subsets by patient sex and age suggest that both sexes receive benefit, although female patients may receive somewhat greater amounts than male patients. There is a consistent trea tmentassociated effect between subsets greater than and less than age 65. There were too few non-Caucasian patients enrolled to draw any conclusions regarding relative efficacy in racial subsets.
Andrew M. Blumenfeld is director of The Headache Center of Southern California. Most of his research has focused on the use of OnabotulinumtoxinA in the treatment of chronic migraine. He helped develop the injection paradigm approved by the United States Food and Drug Administration and has taught providers around the world on practical aspects of this treatment option.
Botox for migraines has been something that has flown under the radar, as many people know Botox as a procedure simply aimed at hiding fine lines. We turned to Matthew S. Robbins, MD, director of inpatient services at Montefiore Headache Center and the chief of neurology at the Jack D. Weiler Hospital, Montefiore, to break down the procedure for us. Scroll down to see what he has to say.
Why Cheap Shady beauty "bargains" on Injectables Can Be So Dangerous- issues are widespread across the US as demand for injectables grows-"I'd say 1 in 4 [bargain hunters] suffers some kind of complication” Manjula Jegasothy MD @MiamiSkinIns https://www.cosmopolitan.com/style-beauty/beauty/a23417647/the-ugly-side-of-beauty-bargains/ … @Cosmopolitan
Allergan’s Phase 3 hypothesis for securing conditional accelerated approval is to demonstrate that CVC treatment therapeutically initiates and induces improvement in histological hepatic fibrosis without worsening of NASH resolution. Notably, establishing improvement in NASH resolution after CVC therapy in NASH is not a prerequisite for attaining FDA conditional accelerated approval. A Phase 3 interim data readout for FDA Subpart H conditional accelerated approval is anticipated possibly in H1/2019.
Prevention of contractures begins with finding out what is limiting a child from either actively (moving oneself) or passively (being moved by someone else) moving the joints through a full range of motion. In some cases, this can be due to destruction or abnormality of the bones around a joint. It can also be due to problems with the ligaments and tissue around that joint.

I increase the dose at each treatment cycle to 195 units. This is based on experience with patients with cervical dystonia, in whom higher doses result in a longer duration of effect. In addition, I transition to the next onabotulinumtoxinA treatment at 12 weeks by using occipital and trigeminal nerve blocks at 10 weeks. Most insurance companies will not cover onabotulinumtoxinA treatments earlier than 12 weeks, but in rare cases, 10-week cycles have been approved.
Botox only lasts three to six months—and yet what's less commonly discussed is this: Facial muscles naturally weaken over time and going overboard in a certain area could have unwanted consequences. "If you do too much Botox on your forehead for many, many years, the muscles will get weaker and flatter," cautions Wexler, adding that the skin can also appear thinner and looser. Moreover, as your muscles become weaker, they can start to recruit surrounding muscles when you make facial expressions. "If one stops using their forehead muscles, they may start squinting using their nose and have wrinkles along the side of their nose," she explains. Translation: You need even more Botox for the newly recruited muscles, says Wexler. To avoid these kind of missteps, researching a doctor diligently is essential, as is approaching injectables conservatively, and asking questions about how the treatment will be tailored to your needs.
It may be the most well known, but Botox is just one type of neurotoxin on the market. Other, next-level neurotoxins are Dysport, FDA-approved in 2009, and Xeomin, FDA-approved in 2011. “They all originate from the same strain of bacteria, therefore they work essentially in the same way,” explains Z. Paul Lorenc, MD, a board certified aesthetic plastic surgeon in Manhattan. “There are some nuanced differences between the three,” he adds. Xeomin is a purified neurotoxin, also called a “naked molecule,” because it doesn’t contain any extra surface proteins, the way Botox and Dysport do. This “pure” neurotoxin migrates deeper into skin, works faster, and poses less risk of an allergic reaction. “Theoretically, decreasing the protein load also lessens the chance of becoming a non-responder, meaning it lessens the chance that the patient will become immune to the neuromodulator being injected,” Dr. Lorenc says. Dysport tends to spread a little more than Botox, so it’s good for areas that would otherwise need multiple injections. It also kicks in faster than the other two, typically showing effects after two to three days opposed to seven to ten days with Botox, and five to six days with Xeomin. Once you try the different neurotoxins, you might decide you like one brand better than the others.
Migraine with visual aura involves visual effects that usually precede the headache and last at least 5 minutes. The visual aura is usually an expanding blinding spot or visual scintillations (shimmering objects in the visual field). Other aura features include reversible symptoms of speech and language difficulty such as word-finding problems and aphasia (inability to express words or comprehend words), sensory phenomena such as tingling in the extremities extending to the face, motor effects such as weakness, and brainstem problems such as unsteadiness and features of cranial nerve dysfunction. These aura symptoms usually last 5 to 60 minutes, can precede or start during the headache, and can also occur without a headache.
Botox is so commonplace these days that you can get it done at some gyms and spas, but in these cases, you never know what you’re getting, how old the product is, with what it's mixed, and whether the injector knows what he or she is doing. Dr. Matarasso suggests only getting it done by what he calls the “core four”: a board-certified physician who is either a dermatologist, a plastic surgeon, an ear-nose-and-throat doctor, or an ophthalmologist. 

I had no idea my health insurance could take Botox away from me. I checked Cigna’s policy and found out that in order to continue receiving Botox coverage after one year, I need to get at least seven fewer migraine days — or at least 100 fewer migraine hours — per month compared to pre-Botox treatments. (I keep a diary to record when I have migraines.) Worse still, if I were to change my job — and therefore change my health insurance — my new insurance could ask me to run through the cheap medication gauntlet again before covering Botox.
But it could be something else altogether. In 2008, Matteo Caleo, a researcher at the Italian National Research Council's Institute of Neuroscience in Pisa, published a controversial study showing that when he injected the muscles of rats with Botox, he found evidence of the drug in the brain stem. He also injected Botox into one side of the brain in mice and found that it spread to the opposite side. That suggested the toxin could access the nervous system and the brain.

The frontalis muscle attaches to the skin of the lower forehead and ascends to join the fronto-occipital aponeurosis. The action of the frontalis muscle involves elevation of the eyebrows to produce expressions such as surprise, and can cause deep transverse wrinkles on the forehead. The antagonists for brow depression are the corrugators, procerus, and orbicularis oculi muscles.

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The potency Units of BOTOX® Cosmetic are specific to the preparation and assay method utilized. They are not interchangeable with other preparations of botulinum toxin products and, therefore, units of biological activity of BOTOX® Cosmetic cannot be compared to nor converted into units of any other botulinum toxin products assessed with any other specific assay method.
There's been a pivotal shift in how women in their 20s look at their faces. And while the reasons are arguably as multi-faceted as this new generation itself, many would agree on one thing: The impact of social media, from selfies to YouTube videos to meticulously crafted Snapchat and Insta Stories, combined with endlessly retouched photographs in magazines and ad campaigns, can not be underestimated. From the constant stream of supernaturally smooth jawlines and chiseled cheekbones to celebrity plastic surgeons posting before-and-after images of their work, the age of 24/7 self-documentation has spurred a novel set of beauty ideals—and, with it, a dramatic increase in cosmetic procedures. For 20-somethings, there's no treatment more popular—or controversial—than Botox. Need proof? According to the American Society of Plastic Surgeons, botulinum toxin procedures have increased 28 percent since 2010 amongst 20 to 29-year-olds.

Still, Botox's use for depression raises a question that confounds some researchers. In some cases, how Botox works is evident: the toxin can block the signals between nerves and muscles, which is why it can help calm an overactive bladder, say, or a twitching eye, or the facial muscles that make wrinkles more apparent. In other cases, however (with migraines as well as with depression), scientists are flummoxed. They may have noticed that the drug works for a given condition, but they aren't always sure why--in sciencespeak, they don't know what the mechanism is.
Strabismus is caused by imbalances in the actions of muscles that rotate the eyes, and can sometimes be relieved by weakening a muscle that pulls too strongly, or pulls against one that has been weakened by disease or trauma. Muscles weakened by toxin injection recover from paralysis after several months, so it might seem that injection would then need to be repeated. However, muscles adapt to the lengths at which they are chronically held,[18] so that if a paralyzed muscle is stretched by its antagonist, it grows longer, while the antagonist shortens, yielding a permanent effect. If there is good binocular vision, the brain mechanism of motor fusion, which aligns the eyes on a target visible to both, can stabilize the corrected alignment.
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