PD Dr. med. Dr. h.c. Klaus Exner is a renowned expert in the field of plastic and aesthetic surgery with an impressive career spanning more than forty years. In addition to his extensive expertise in hand surgery and microsurgery, he has made a name for himself in the international medical community through numerous awards and accolades.
His expertise spans various areas of aesthetic and plastic surgery, including facial and body aesthetic surgery, breast surgery—such as reconstructions, reductions, and augmentations, as well as tumor surgery, particularly for skin, soft tissue, and breast tumors. He also performs body contouring procedures and offers treatments such as facelifts, blepharoplasty, and rhinoplasty. Furthermore, he specializes in the treatment of congenital malformations such as cleft lip, cleft palate, and cleft jaw, as well as breast asymmetries.
As one of the leading experts in his field, Dr. Exner is recognized worldwide and has made significant contributions to the development of advanced medical care through his many years of practice, research, and teaching, as well as through numerous innovations. His scientific publications and his involvement in the development of new surgical techniques have helped raise the standards in aesthetic and plastic surgery.
Dr. Exner practices at two state-of-the-art locations in Frankfurt am Main and in Oberursel in the Hochtaunus region, offering his patients personalized treatment of the highest quality, tailored to their individual needs. He places great importance on building a trusting relationship with his patients and thoroughly understanding their wishes and expectations. His expertise encompasses a wide range of aesthetic and plastic procedures, in which he achieves natural and aesthetically pleasing results through innovative techniques such as lipo-filling.
In addition, Dr. Exner is actively involved in research and the further development of surgical methods so that he can consistently offer his patients the most modern and effective treatment options. Through his humanitarian work in poorer regions of the world—particularly through his missions in developing countries such as Myanmar and Ukraine—Dr. Exner has not only demonstrated his medical expertise but has also made a significant contribution to improving medical care in these regions. His outstanding contribution to the entire field of aesthetic and
plastic surgery is documented by numerous awards and honors, as well as by his scientific and humanitarian work around the world. Facial paralysis is also one of the areas of expertise of this experienced specialist.
The editorial team of the Leading Medicine Guide spoke with Dr. Exner about facial paralysis.
Facial nerve palsy, also known as facial paralysis, is a neurological disorder caused by damage to the facial nerve, which controls the muscles of the face. The effects can range from mild weakness to complete paralysis, which can impair both the aesthetic appearance and the functional ability of the face. A deeper understanding of facial nerve palsy is crucial for the diagnosis and treatment of this condition, as well as for supporting those affected during their recovery process.
Acquired facial nerve palsy is a sudden weakness or paralysis of the facial muscles caused by damage to the facial nerve.
This form of palsy can have various causes, including infections, trauma, inflammatory diseases, tumors, or idiopathic cases where the exact cause is unknown. “Facial palsy most commonly results from cranial nerve surgery. Most often, it is surgery for an acoustic neuroma or other brain tumors that can trigger this form of palsy. This is because the acoustic nerve—that is, the hearing nerve—runs at a critical point directly adjacent to the facial nerve. And in rare cases, the auditory nerve has the unfortunate tendency to form a lump—a benign neurinoma. However, if the auditory nerve is damaged, patients experience symptoms such as episodes of dizziness, reduced hearing, or tinnitus. To prevent the neurinoma from growing further and building up pressure, it is usually removed surgically. In the past, damage to the facial nerve occurred very frequently during these procedures, but this is less common today because monitoring during the procedure has improved significantly. During the operation, electrodes are attached to the facial muscles, and nerve recordings on the monitor allow surgeons to see when they are getting too close to the facial nerve or putting too much strain on it. Unlike in the past, the entire operation is less invasive because much of the tissue can be removed using ultrasound. Nevertheless, there are still many complications following these neurinoma surgeries. The facial nerve branches into a frontal branch that runs from the temple up to the forehead and controls the facial muscles of the forehead. There are also important branches to the eyelid, specifically to the eyelid-closing muscle. And this is where a major problem arises for patients with facial nerve palsy: they can no longer close their eyes. As a result, the eye can dry out, the cornea can scar, and this can even lead to blindness. “Ultimately, the facial nerve controls all facial expressions—the movement of the nostrils, for example, or the protrusion of the lips,” says Dr. Exner regarding the effects of facial nerve palsy.
An acoustic neuroma, also known as a vestibular schwannoma, is a benign tumor that develops from the Schwann cells of the vestibular nerve (nervus vestibularis). This nerve is part of the eighth cranial nerve, which is responsible for hearing and balance. Acoustic neuromas typically grow slowly and often cause symptoms such as hearing loss, tinnitus (ringing in the ears), and balance disorders. Since the tumor can affect the brainstem and other important structures within the cranial cavity, early diagnosis and treatment are important. Treatment options include regular monitoring, surgical removal, and radiation therapy, depending on the tumor’s size and location, as well as the patient’s overall health.
The course of facial nerve paralysis caused by an acoustic neuroma depends on various factors, including the size and location of the tumor, as well as the extent of compression on the facial nerve. In some cases, facial nerve paralysis may progress as the tumor continues to grow and exerts more pressure on the nerve. In other cases, facial paralysis may remain stable or even improve once the tumor is treated and pressure on the nerve is reduced. Treatment of an acoustic neuroma with accompanying facial nerve palsy may include various options, such as monitoring the tumor, radiation therapy, or surgical removal of the tumor. The choice of treatment depends on the size and location of the tumor, the extent of the facial nerve palsy, the patient’s overall health, and other individual factors. In some cases, physical therapy may be recommended to improve facial function and support recovery following treatment of the tumor.
Congenital facial nerve palsy occurs when the facial nerve is damaged at birth.
This form of facial paralysis can have various causes, including genetic factors, infections during pregnancy, or birth trauma. Typical symptoms include asymmetrical facial expressions, difficulty closing the eye on the affected side, and limited muscle movement in the face. In such cases, physical therapy, surgical intervention, or a combination of both therapies may be considered. Möbius syndrome is a rare congenital disorder caused by the absence or underdevelopment of the sixth and seventh cranial nerves, leading to facial paralysis. “In this condition, the entire facial nerve does not function at all. It becomes noticeable in children because, at first, they are unable to drink or smile. They cannot close their eyelids properly and often squint. The condition can be further complicated by the development of clubfoot and muscular dystrophy. The masseter nerve, which originates from the masticatory muscles, has played a major role because small muscle grafts could be attached to it. To do this, a piece of muscle—including nerves and blood vessels—is taken from another part of the body, such as the inner thigh, and connected via microsurgery to the blood vessels of the facial muscle and to the masseter nerve. “This allows a child to mimic a smile, tense their face, and speak more clearly,” explains Dr. Exner.
The exact prevalence of Möbius syndrome in Germany is not precisely known due to its rarity and possible underdiagnosis. However, it is estimated that approximately 1 in 50,000 to 1 in 500,000 newborns are affected by this syndrome.
Treatment for acquired facial nerve palsy depends on the underlying cause and the severity of the symptoms.
In some cases, the paralysis may resolve spontaneously and completely, while in others, treatment is necessary to alleviate symptoms and improve facial function. “Infections caused by viruses such as the herpes simplex virus or the varicella-zoster virus, as well as autoimmune diseases such as Lyme disease (transmitted by ticks) or sarcoidosis, can inflame the facial nerves and lead to facial nerve palsy. Traumatic facial injuries, such as lacerations, skull fractures, or tumors that compress the facial nerve, are other possible causes. The facial nerve runs through the facial canal in the area of the middle ear. In cases of severe inflammation or abscesses in this area, the nerve can be compressed so severely within this bony canal that it sustains serious damage or fails to function. In addition, nerve dysfunction frequently occurs in connection with vaccinations; while this is usually temporary—for example, after the early-summer TBE (tick-borne encephalitis) vaccine, which protects against viruses transmitted by ticks— In such cases, however, it’s not uncommon for children to limp for a while, though this usually resolves on its own. That said, I have certainly had quite a few patients (undoubtedly also due to the increase in vaccinations in recent years) who developed facial nerve palsy as a result of a vaccination. And there are now significantly more patients affected by the herpes zoster virus than was the case before COVID. In so-called idiopathic cases, on the other hand, patients wake up in the morning and suddenly find they can no longer move one side of their face. “We don’t know exactly what causes this, but we suspect undiagnosed infections such as the herpes virus mentioned above, which can also trigger shingles—a condition in which the nerve pathways are severely affected,” explains Dr. Exner, adding a few more details about diagnosis and initial treatment:
“Facial nerve palsy is essentially a visual diagnosis. Imaging procedures such as magnetic resonance imaging (MRI) are frequently performed to look for possible causes such as tumors or injuries, while electrophysiological tests such as electromyography (EMG) can assess the nerve’s function and help determine whether there are still nerve impulses present that may become noticeable after a few weeks or months. In the past, patients were kept waiting too long, and this resulted in the loss of very valuable time. This is because the 23 muscles responsible for facial movements atrophy when they lack nerve supply. The connection between the nerve and the muscle is then severed, and the muscle can no longer contract. Today, during this phase, a so-called “babysitter nerve” can be implanted to send the necessary impulses and bridge the period during which it is not yet known whether the facial nerve will regenerate. The masseteric nerve, which is associated with the masseter muscle, is used for this purpose. Sometimes this is sufficient, and sometimes additional nerve grafts are used to restore facial expressions that are as symmetrical as possible.”
Microsurgical techniques for treating facial nerve palsy offer precise and targeted approaches to improve or restore the impaired function of the facial nerve.
Regarding treatment options in general, Dr. Exner explains: “A distinction is made between static and dynamic methods. Static methods (such as small gold pieces in the eyelid to facilitate closing) are always only stopgap solutions, whereas dynamic methods are always the preferred goal, especially with regard to restoring facial expressions. In cases of congenital facial nerve palsy, microsurgical muscle transplantation is the only option. For this, the technique developed by Sir Harold Gillies in 1937 is used to reroute the temporalis muscle (the chewing muscle in the temple region) to the eye, thereby enabling the eyelid to close again using this muscle. In addition, there is the McLaughlin technique, described in 1956, in which tendon strips are harvested from the thigh and connected to the masticatory muscles to mimic a smile and lift the face again. This technique is generally used in patients over the age of 50 or 60. Botox can be used for minor asymmetries and is injected on the side where the nerve is still healthy. This restores symmetry by reducing nerve activity on the healthy side and inducing an adjustment.”
The use of Botox for facial nerve palsy requires careful assessment and planning by an experienced physician with expertise in treating this condition. The dosage and placement of the injections should be tailored to each individual, based on the patient’s specific needs and symptoms, to achieve optimal results and minimize potential side effects. Although Botox can be an effective option for treating certain symptoms of facial paralysis, it is important to note that there is no cure for this condition. The use of Botox aims to alleviate symptoms and improve the quality of life for those affected, but it should be considered as part of a comprehensive treatment plan that may also include physical therapy, surgical procedures, and other therapies.
Microsurgical Treatment Options
“Microsurgical procedures involve transplanting muscles along with blood vessels, but they also include the option of connecting the masseter nerve to the facial nerve and linking it to branches of the facial nerve—that is, the nerve fibers. Nerve grafts can also be performed using the so-called cross-face technique. In this procedure, nerves are taken from a healthy site—usually the lower leg—and can be placed, for example, under the upper lip (on the affected side). After some time, the Hoffmann-Tinel sign (a clinical sign used to diagnose nerve injuries and irritations) is used to check whether the patient feels a tingling sensation at the site, which indicates whether the nerve has already taken root. This is important because when a nerve is transplanted, the nerve’s core—the axon—is initially nonfunctional. However, through the nerve sheath that has been sutured in place, the axon regrows at a rate of 1–2 mm per day. And then, by tapping the area, one can determine whether the nerve has reached the other side. That is the right time to connect a muscle to the nerve using vascular anastomoses in order to restore facial function. “The transplanted muscle should, of course, be a very fine muscle so that it isn’t very visible on the face. We’re talking about high-tech microsurgery here,” explains Dr. Exner.
The Hoffmann-Tinel sign, also known simply as the Tinel sign, is a clinical sign used to diagnose nerve injuries and irritations. It is performed by gently tapping or pressing over a nerve to determine whether this triggers a tingling or unpleasant sensation along the nerve. It is a helpful diagnostic tool for identifying nerve problems and localizing the area of nerve damage or compression.
Compared to nonsurgical treatment methods, microsurgical procedures directly target the cause of facial nerve palsy rather than merely alleviating the symptoms. They offer the possibility of permanent restoration of facial function and can be particularly beneficial in cases of advanced facial nerve palsy. However, microsurgical procedures require careful planning and execution, as well as a longer postoperative rehabilitation process. It is important that these procedures be performed by experienced and specialized surgeons to achieve optimal results and minimize potential complications.
“I personally often recommend that my patients seek additional information from colleagues at other centers, which they are happy to do. Then the patient can decide where to ultimately go for treatment. Especially when it comes to young patients, they simply need sound advice from several experienced centers to achieve the best possible treatment with the best possible outcome. They also need psychological support. Patients who still have some residual function of the facial nerve can also do exercises in front of a mirror to train the nerve. Tips on cosmetics and speech therapy are also important at this stage,” Dr. Exner recommends at the end of our conversation.
Thank you very much, Dr. Exner, for these informative insights on facial nerve palsy!
