At least 25% of the German population (corresponding to 20 million people) have goiter. Around a third have additional knots. A maximum of 5 million people are treated (25% of those affected), more than 15 million remain untreated. 100,000 thyroid surgeries are performed in Germany each year, 80% of which are due to goiter plus complications. Possible side effects: recurrence paresis, 3 to 4% early postoperatively, permanently less than 1%. An additional 35,000 radioiodine therapies are carried out in Germany. A large number of them also because of goiter plus complications. The aim is therefore to take appropriate measures to remedy the iodine deficiency in Germany, to inform those affected about causes, consequences and preventive measures, and to motivate 20 million goiter carriers to consult their doctor in good time.
When is thyroid surgery necessary?
As a rule, there is a absolute duty to operate on any suspected malignancy. Thyroid surgery may also be necessary or at least recommended for benign diseases.
Possible reasons for thyroid surgery:
- Cancer and suspected cancer ("suspicious node")
- Thyroid enlargement (goiter)
- Glandular growth (adenoma)
- Cavitation (cyst)
- Graves' disease
It is not uncommon for there to be several reasons for an operation at the same time, whereby there can be different arguments for or against an operation. In addition to objective factors (such as constriction of the trachea, expansion of the thyroid gland into the chest), subjective factors such as complaints or the patient's desire for unequivocal histological clarification also play a role.
Possible treatment alternatives should also be discussed when deciding whether or not to operate. There are e.g. in the event of an overfunction that can be controlled as a single finding by radioiodine therapy (further information) or purely medicinal treatment (further information).
With a large goiter, on the other hand, surgery is clearly the first therapy recommendation. An alternative attempt at reduction with radioiodine would only be advisable if there are important reasons against an operation (e.g. a too high surgical risk in sick patients) or if the patient refuses an operation.
Good reasons for an operation
The surgery is the only treatment in which the desired effect (e.g. size reduction, elimination of hormone production) occurs immediately. With thyroid surgery, all pathological changes (e.g. hot, warm and cold nodes) can be treated at the same time. In addition, an individual and diagnosis-oriented treatment is possible during the operation: from the economical partial removal of a flap to the complete removal of the thyroid gland.
Only the microscopic examination of the removed thyroid tissue by a pathologist can clearly distinguish benign and malignant. German surgeons find that every second patient with thyroid cancer had no suspicion of malignancy in advance. The cancer was always found as a coincidence during the careful examination of the surgical preparations. So-called hidden thyroid carcinomas discovered by chance in the surgical specimen are usually considered cured - a weighty argument for surgery.
What are the risks of an operation?
With an experienced surgeon, thyroid surgery is usually uneventful. The general risk of surgery (for pneumonia, thrombosis, heart attacks, etc.) is minimal and the mortality rate from surgery is close to zero. General complications occur in good clinics with an overall frequency of less than 5 percent.
Wound healing disorder, infection
Despite all the precautions and advances, even with thyroid surgery, there is a minimal residual risk of inflammation or impaired wound healing. However, this is less than 2 percent. Most infections heal quickly and without consequences under local treatment.
Minor bleeding or bruising can also occur after thyroid surgery. This can cause uncomfortable feelings of pressure or breathing problems. Such bruises are surgically removed through the existing skin incision. Life-threatening bleeding is very rare.
Voice and speech disorders
Special risks in thyroid surgery are injuries to the small parathyroid glands as well as voice and speech disorders: The immediate anatomical proximity of the thyroid to the larynx and vocal cord nerves can have various effects on voice and speech formation during the operation.
Surgery and anesthetic-related swelling and irritation in the neck area usually resolve within a few days.
In contrast, damage to a vocal cord nerve leads to paralysis of the associated vocal cord (recurrence palsy). If only one side is damaged, the patient can speak and communicate. However, the voice usually sounds hoarse to croaky. If both vocal cords are paralyzed (very rare), shortness of breath may also occur. In this case, a so-called tracheostomy may be required.
Depending on the cause of the damage, most pareses recover on their own. If the voice quality is not completely restored, good voice and speech therapy (speech therapy) can usually achieve a satisfactory result.
The risk of nerve injury also depends on the operating conditions. Repeat and cancer surgery or surgery on very large goitre are generally associated with a higher risk. Nevertheless, the risk of injury to the vocal cord nerve in excellent surgeons is on average not more than 1 percent.
The fear of voice and language disorders is great in many patients, but is usually unfounded in the hands of experienced surgeons.
The parathyroid glands are also anatomically very close to the thyroid gland and can therefore be inadvertently damaged or removed during extensive operations.
Parathyroid hormone is formed in the parathyroid glands. This hormone controls the blood concentration of calcium, which in turn affects nerve and muscle function and bone metabolism. If there is a lack of parathyroid hormone (hypoparathyroidism) as a result of the operation, the calcium concentration in the blood drops. As a result, there are sensations such as tingling sensations or muscle cramps, which are treated with medication by calcium and / or vitamin D preparations.
The risk of this complication varies depending on the surgical procedure, but is at most 1 percent for an experienced thyroid specialist.
What modern surgical techniques are there in thyroid surgery?
Depending on where and how much thyroid tissue is removed or left, a distinction is made between different types of surgery (resections). These range from the economical peeling of a knot to the complete removal of both thyroid lobes.
Most of the procedures have basic advantages and disadvantages. This concerns operational aspects, surgical levels of difficulty, special complications and last but not least the late results in the long-term course.
In limited operations, the pathological finding is removed from the thyroid either along its capsule (enucleation) or with a hem of healthy thyroid tissue (wedge excision). If the diseased change is limited to the tissue bridge between both thyroid lobes (isthmus), this tissue bridge may also be removed (isthmus resection).
These limited procedures are only used if there is an isolated pathological finding in an otherwise healthy thyroid. This requirement usually only applies to smaller nodules or cysts. Depending on the specific location and size of the node, it can usually only be decided during the operation whether a limited resection makes sense. Often there are several pathological changes on their own or in combination with an enlargement of the thyroid gland. Then more pathological thyroid tissue must also be removed.
Depending on how much tissue can be left, these operations are referred to as subtotal flap resection (thyroid gland about 4 grams and less), almost total flap resection (thyroid gland 1 gram and less) or complete flap resection (hemithyroidectomy, no rest on the operated side) , Since there are two thyroid lobes and both lobes are often diseased, all of the resection procedures mentioned can either be isolated on one side or combined in all possible variations on both sides of the lobe.
Minimally invasive surgical procedures
In conventional surgery, the skin incision is made on the front of the neck in the lower parts (Kocher's collar cut). If possible, an existing or suggestive fold is used for the skin incision. With a well-planned cut and aesthetic seam technology, this usually results in very good cosmetic results. In order to keep the scars as small and invisible as possible, various minimally invasive surgical techniques have been developed in recent years.
... with a cut on the neck:
To improve the cosmetic result, the skin incisions on the neck are made as short and tight as possible. With special instruments, the thyroid is either viewed and operated under direct vision (e.g. MIT, minimal incision thyroidectomy) or with a miniature camera (MIVAT, minimally invasive video assisted thyroidectomy).
... without a cut on the neck:
With other minimally invasive surgical procedures, the incisions are not in the visible parts of the neck. With the ABBA method (axillo-bilateral-breast approach), for example, two incisions are made on the edge of the right and left nipple and in the right or left armpit. The surgical instruments and the camera are guided under the skin to the thyroid gland. Since the surgical specimen must be removed via one of these approaches, this method is only suitable for a few and very small changes in the thyroid gland.
Other methods - from the hairy neck or through the mouth - are currently being tested. It is still unclear whether they will benefit the patient and will prevail.
A central concern of modern thyroid surgery is the greatest possible protection of vulnerable structures, such as the fine vocal cord nerves or the small parathyroid glands. These structures can be optically enlarged by means of aids and can thus be better recognized and protected. Magnifying glasses are available in various magnification levels and surgical microscopes.
If very fine surgical instruments are also used, important parts of the surgical procedure can be performed using microsurgical operating technology. This is helpful if e.g. a vocal cord nerve must be carefully removed from adhesions and nodes or the tumors surrounding it.
Intraoperative neuromonitoring provides additional help to protect nerves. The principle is "stimulation and stimulus response". The surgeon can use a fine probe to regularly emit minimal current surges during the procedure. If the irritated structure is the vocal cord nerve and it is intact, the nerve transmits the impulse to the responsible larynx muscle in accordance with its task and the vocal cord opens.
Today, this is usually controlled using a special ventilation tube. The tube is a silicone tube that is inserted into the trachea between the vocal cords for ventilation of the patient during every general anesthetic. Fine electrodes are incorporated at the level of the vocal cords for neuromonitoring. This way, the doctor can convince himself of the functionality of the control loop at any time and adapt the surgical tactics.
The technology is already routinely used in many hospitals. However, neuromonitoring is a very sensitive and also prone to failure method. And does not give 100 percent accuracy.
Protection of the parathyroid glands
In addition to the delicate vocal cord nerves, the surgeon's attention also focuses on the small parathyroid glands. Sometimes they do not have an independent blood supply, but are supplied by blood vessels of the thyroid gland. Then, after removing the organ, the parathyroid glands may have poor circulation. Due to the possibility of intraoperative parathyroid hormone determination, a hormone drop can be recognized or excluded during the operation.
The functioning of a poorly perfused parathyroid can be saved by auto-replantation. For this purpose, such a parathyroid gland is first removed, broken up into many pieces of tissue and replanted in a well-supplied muscle pocket in the operating area. It is also possible to freeze the parathyroid tissue in extreme cold and to implant it again at a later time. If this is successful, parathyroid hormone is also formed at the new location.
What is and how does intraoperative neuromonitoring work?
Intraoperative neuromonitoring is a technical aid for protecting the vocal cord nerves. The principle is "stimulation and stimulus response". In principle, every motor nerve works like a connecting cable that transmits the finest electrical impulses from the control organ to a target organ. In the case of vocal cord innervation, the original signal comes from the brain and is passed on to the vocal cord opener muscle (M. vocalis) via the 10th cranial nerve (vagus nerve) and the vocal cord nerve (recurring nerve). During neuromonitoring, the surgeon uses a fine probe to deliver minimal current surges to the vocal cord nerves running in the surgical area. If the irritated structure is the vocal cord nerve and it is intact, this nerve transmits this impulse to the responsible larynx muscle in accordance with its task, and the vocal cord is opened. The effect on the larynx muscle is usually measured using a special ventilation tube. This tube is a silicone tube that is inserted into the trachea between the vocal cords for ventilation of the patient during general anesthesia. Fine electrodes are incorporated at the level of the vocal cords for neuromonitoring. With these, the electrical reactions of the vocal cord muscles can be determined and measured. The result is a curve that is somewhat similar to an EKG.
The surgeon can then see the electrical stimulus response of the vocal cord muscle very precisely on the monitor (red curve). The time interval between stimulus and response in milliseconds (ms) and the amplitude in millivolts (mV) are important.
Intermittent and continuous neuromonitoring
The surgeon originally targeted the vocal cord nerves with a hand probe and only briefly stimulated them on a random basis (intermittent neuromonitoring). In the case of regular signals, the operation continues. It can happen that the nerve function between two measurements is inadvertently damaged by pulling or pulling or that the fine nerve was even accidentally severed. This is one of the reasons why the routine use of intermittent neuromonitoring has not led to the expected reduction in the rate of unilateral vocal cord paralysis. For this reason, the so-called continuous neuromonitoring was developed. At the beginning of the operation, a fine stimulation probe is placed on the trunk nerve of the vocal cord innervation, the vagus nerve, which continuously delivers fine electrical impulses until the end of the operation. It is therefore possible for the surgeon to continuously receive neuromonitoring signals during the entire operation.
With continuous neuromonitoring, the surgeon can immediately recognize any changes and impending damage online.
If the measured values deteriorate during certain preparation steps, the surgical procedure can be adapted immediately. Newer devices also have an automatic acoustic early warning function for the timely detection of impending damage. At the moment, however, it has not yet been scientifically clarified whether and to what extent continuous neuromonitoring contributes to a further reduction in the already very low rate of vocal cord paralysis in good clinics.
Importance of neuromonitoring in planned bilateral surgery
Intraoperative neuromonitoring makes a very important contribution to avoiding bilateral recurrence savings. While one-sided recurrence palsy essentially “only” leads to a change in the speech and voice function, with both-sided recurrence palsy, breathing difficulties can also occur (inspiratory stridor), so that a trachotomy can be necessary to ensure breathing. Of course, this should be avoided under all circumstances. For this reason, intraoperative neuromonitoring control of the vocal cord function should be carried out in a planned bilateral surgery after removal of the first thyroid lobe. If the control reveals clear and unchanged results when the trunk nerve (vagus nerve) is stimulated, it can be assumed that the vocal cord innervation has remained intact. If the control gives no or no clear findings, even if the vocal cord nerves are visually unremarkable, one cannot be sure whether the nerve is functioning properly or whether there is a recurrence palsy due to swelling or strain. In order to definitely avoid recurrent palsy on both sides, the simultaneous operation of the opposite side should be avoided for safety reasons. Since a signal loss during neuromonitoring also others, e.g. technical reasons, in such cases a vocal cord function should be checked quickly by an ENT doctor after the operation. If the vocal cord works correctly despite the loss of signal, the opposite side could be operated on promptly. If there is actually a vocal cord palsy, a necessary operation on the opposite side should only be carried out after the functional recovery of the paralyzed vocal cord to be hoped for.
Routine neuromonitoring during thyroid surgery
In addition to the aspect of intraoperative functional control, neuromonitoring can be very helpful to the surgeon, particularly in difficult operating conditions such as operations in adhesions (relapses) or extensive cancer operations when locating the vocal cord nerves. Therefore, all operative members of the German Thyroid Center have committed to routinely use intraoperative neuromonitoring in all thyroid operations. However, it should be pointed out that - at least so far - neuromonitoring does not yet guarantee 100 percent certainty to prevent vocal cord paralysis and that the experience and quality of the surgeon is still of central importance.
How are benign thyroid diseases operated on?
The surgical intervention should safely and reliably remove all pathological changes in the thyroid gland. Because even with benign diseases there is a risk of relapse. Statistically speaking, there were up to 40 percent repetitive interventions in the case of pure knot removal. In order to avoid repeated operations, more than too little tissue is therefore removed from many diseases. This applies particularly to diseases that mostly affect the entire thyroid, e.g. Graves' disease, goiter multinodosa.
As a rule, it is only during the operation that a final decision is made as to whether and how much tissue needs to be removed. Because sometimes more pathological changes are detected than were suspected before the operation. Then the procedure should be adjusted accordingly. The basic strategy and the possible deviations are coordinated with the patient before the operation.
Basically, all classic surgical procedures are used in the operation of benign changes. If only one thyroid lobe becomes ill and the other is healthy, usually only one-sided surgery is performed. Then it is best to remove the diseased flap completely (hemithyroidectomy). This has the advantage that this side is permanently healed and there is no need to operate on these vocal cord nerves and parathyroid glands again. The remaining thyroid flap can take over the complete function of the thyroid after a certain adjustment time.
However, there are often pathological changes in both thyroid lobes. If possible, these are removed at the same time. Depending on the patient's findings and wishes, more or less large thyroid remnants are left on one or both sides or the thyroid is completely removed.
Operational tactics also play a role in the decision. To avoid risks and complications, it can make sense in certain situations that e.g. No radical intervention is forced near the parathyroid glands or the vocal cord nerve. The same applies if e.g. after surgery on the first thyroid lobe, it is not clear whether the vocal cord nerve is still functioning properly. In order not to endanger the other vocal cord in addition and to avoid bilateral vocal cord paralysis, the other side is not operated at all, or only defensively.
How are malignant thyroid diseases operated on?
First of all, thyroid cancer is rare. Less than one percent of all thyroid nodules prove to be malignant. With thyroid cancer, complete surgical removal is the most important prerequisite for permanent healing.
With a few exceptions (isolated papillary or follicular early carcinomas), radical cancer surgery consists of the complete removal of the thyroid gland (thyroidectomy) in combination with a systematic removal of the lymphatic drainage pathways (lymphadenectomy). Such cancer surgery is only carried out if there is no doubt about the malignancy of the tumor.
The extent of the lymph node clearance depends on the specific type of tumor, the stage of spread and the intraoperative finding. As a rule, at least the central lymphatic stations around both thyroid lobes are removed. In an area bounded below by the sternum and at the top by the hyoid bone, laterally by the right and left carotid artery, the surgeon removes all lymphatic tissue around the larynx, trachea and esophagus.
Sometimes the lymph nodes in the side of the neck (lateral compartment) or in the upper chest under the sternum (mediastinal compartment) must also be cleared. Lymphadenectomy is a complex surgical procedure that should only be performed by very experienced surgeons. On the one hand, the lymph nodes with possible tumor colonization must be completely removed, on the other hand, important structures such as nerves, vessels and cervical organs must be protected. In the past, this required relatively large cuts. With the appropriate experience and technique, a systematic lymphadenectomy can now be performed on a very small skin incision that is not significantly larger than that of normal thyroid surgery.
Operation: procedure and aftercare
Patients who deal with thyroid surgery in advance are better informed. They know what to expect, they can have a say in the treatment and support the healing positively.
How does the operation preparation look like?
In most good clinics, the processes involved in thyroid surgery are basically comparable. In detail there are of course differences and special features between different surgeons and clinics. The definitive decision for thyroid surgery and the selection of the right surgical procedure require a series of preliminary examinations. These are usually carried out on an outpatient basis.
To assess the thyroid gland and plan the operation, it is important to:
- the determination of the thyroid levels in the blood
- an ultrasound scan
- a scintigraphy of the thyroid gland
- a functional check of the vocal cords by an ENT doctor
To assess the ability to perform surgery and anesthesia, you need
- a laboratory blood test
- sometimes an EKG
- possibly an X-ray examination of the chest
Most of the patients are referred to their outpatient consultation by their family doctor, nuclear medicine doctor or endocrinologist with the corresponding examination findings. There surgeons and anesthesiologists can prepare the operation and anesthesia to such an extent that the patient does not come back to the hospital until the scheduled surgery date.
What happens on the day of surgery?
Before the procedure
Thyroid surgery is usually performed under general anesthesia. Therefore, on the day of the operation, nothing should be eaten, drunk or smoked before the procedure. The patient puts on special surgical clothing for the operation. At the nursing station, he already receives various drugs for anesthesia preparation and calming down (premedication). Finally, the nursing staff drives him to the operating room in his bed.
During the operation
An infusion (drip) is applied to one arm during the operation. Sometimes one or two thin catheters (drainages) are inserted into the surgical wound on the neck to drain blood and wound fluid, which are connected to small drainage containers. In order to avoid additional scars, any drainage is removed directly from the wound and not at another point in the skin and removed as soon as possible.
The wound is closed at the end of the operation. In Germany a so-called intracutaneous suture is used. With this special technique, the suture is pierced on one side of the wound, guided invisibly in the skin and cut out at the other end. This means that only a single thread is required for the entire seam. In addition, the wound edges are optimally adapted using special brownish plaster plasters. The patches also protect against infection and pollution. A gauze compress and a sterile, white wound plaster are glued over it.
After the procedure
If there are no special features, the patient is picked up by the nursing staff from the operating room in his bed after the operation and taken to a ward room. The patient routinely receives appropriate medication for wound pain and swelling, so that no significant pain is to be expected. If this therapy is not sufficient in individual cases, stronger medication can be administered.
If the course is smooth, patients can drink, eat, get up in the company of a nurse and use the toilet just a few hours after the operation.
How are the days after the operation?
The aim of further treatment is to restore the patient's physical and mental state as quickly as possible. The so-called fast-track concept, which begins immediately after the operation, serves this purpose. These include an optimized pain therapy, early mobilization, an early food supply and the earliest possible avoidance of infusions, catheters and drainage.
After interventions on the thyroid gland, a specially designed cold, breathing and inhalation treatment is used. Fango packs and physiotherapy are useful for tension. The first dressing change takes place the morning after the operation. If the course is smooth, any drainage and other tubing and infusions are also removed. Thyroid patients can then only be recognized by their fresh plaster.
On the first day after the operation, the patient can take a short shower. Patients are free to move around the ward and hospital from day one. If there are no complications and the wound heals well, most patients can be discharged two to four days after the operation. Each patient receives his individual thyroid passport, in which all important information about the operation and the recommendations for follow-up treatment are documented.
What should you watch out for after-treatment?
Wound healing and stringing
With a regular healing process, the staple plaster and the skin thread are removed exactly seven days after the operation. This is completely painless with the intracutaneous suture. The thread can be drawn both at the family doctor and in the hospital outpatient clinic. Since the fine tissue assessment of the surgical specimens sometimes takes a little time and the definitive finding is usually not yet available when the patient is discharged, many patients like to come to the specialist clinic for threading. In a final discussion, existing questions can also be clarified and the further procedure can be coordinated.
At the time of thread removal, there may still be swelling, hardening or bruising in the scar area. These mostly recede completely on their own. The visible scar will also change in the following weeks: in the final state it should only be fine, light and very soft.
Until the optimal result is achieved, patients sometimes have to be patient. Depending on the constitution and disposition, the fading of the surgical scar can take a few weeks to months. A good cosmetic result can be supported by good scar care.
Follow-up treatment for benign diseases
Since more or less thyroid tissue is removed with every surgical intervention, this also has an influence on the hormonal balance. Basically, the more thyroid tissue is removed, the more pronounced is the drop in hormone levels. The less tissue is removed, the less the hormonal change, but the higher the risk of new knots or enlargement.
The goals of aftercare for benign diseases are therefore the optimal (medicinal) setting of the thyroid hormones and the best possible prevention of relapse (relapse prevention). The type of drug treatment depends on the underlying disease and the size of the remnants of the thyroid gland. If no thyroid tissue is left during the operation, hormone replacement therapy with thyroxine is given.
If a remnant of up to about 6 grams of functional thyroid tissue is left, an underactive function would occur despite the remainder without medication, so that these patients are prescribed thyroxine and iodine at an early stage. If more than about 6 grams of functional thyroid tissue is left in the body, hormone administration can be dispensed with if there is sufficient in-house production. As a rule, such patients only receive iodine tablets for relapse prevention.
Follow-up treatment for malignant diseases
After all the findings are available, it is decided together with the patient whether and which further cancer treatments are required after the operation. In the thyroid center in Cologne, coordination and coordination with the relevant experts takes place with the involvement of the family doctor. A good aftercare serves to monitor the freedom from tumors and the optimal adjustment with thyroid hormones.
Classic radiation or chemotherapy is used very rarely. Radio iodine therapy is most common. Depending on the stage of the tumor, this is done for papillary and follicular thyroid cancers. The extent and intensity of aftercare differ considerably between the individual tumor types and stages and should remain in the hands of a specialist for most cancers, at least for the time being. The prognosis for thyroid cancer depends largely on the type and stage of spread of the tumor and the quality of the surgical therapy.
In general, the chances of a cure are very good, especially with common types of cancer. The diagnosis of cancer is a shock for most patients. It leads to uncertainty and fear. Because not only the body gets cancer. The soul also gets out of balance. It is therefore important to speak openly about the disease. Experience has shown that the exchange with other affected people as well as professional psychosocial support can be very helpful. There are now a number of self-help groups for patients with thyroid cancer in which those affected can find help quickly and personally.
What to do with complications from surgery?
Voice and speech disorders
If there is no complete restoration of voice and speech quality after thyroid surgery, one speaks of a postoperative voice disorder. Then the voice sounds hoarse, quiet or flat, for example. Sometimes there are additional symptoms such as increased speech effort, the need to clear the throat or a feeling of a foreign body.
For an early detection and treatment of voice and speech disorders, an ear, nose and throat doctor should check as soon as possible. This checks the functionality and mobility of the vocal cords and initiates the correct therapy if necessary.
In the case of vocal cord paralysis, intensive speech therapy is given first. If the vocal cord function does not recover or the patient is not satisfied with the result, various surgical correction procedures on the larynx or the vocal cords can be used.
Every operation on the thyroid gland can affect the function of the parathyroid glands. As a result, the calcium concentration in the blood may drop (hypoparathyroidism). Therefore, this value is checked after every thyroid operation. If it is low, the parathyroid hormone level should also be checked.
Overall, the parathyroid glands have enormous recovery potential. Under favorable conditions, even a single well-functioning parathyroid gland can ensure adequate hormone production after a certain adjustment period. However, this can take a few weeks to months.
Until the normalization of parathyroid hormone production, the affected patients are prescribed a calcium supplement and often also vitamin D. It is important to stimulate the remaining parathyroid tissue to produce hormones. To do this, the calcium and then the vitamin D dose must be gradually reduced. The course then shows whether the in-house production is working properly again.