Contents Title Show Contents Title

Fibromuscular Dysplasia Carotid

Understanding Fibromuscular Dysplasia

Fibromuscular Dysplasia Carotid Fibromuscular dysplasia (FMD) is a rare arterial disorder that primarily affects the carotid artery. This condition is characterized by abnormal cell growth in the arterial walls, leading to narrowing and weakening of the artery.

The specific impact of fibromuscular dysplasia on the carotid artery can vary from person to person. In some cases, FMD can cause the carotid artery to become excessively narrow, limiting blood flow to the brain. This can result in symptoms such as dizziness, headaches, and blurred vision.


Get Free Consultation

Please enable JavaScript in your browser to complete this form.
Step 1 of 4
Select Your Gender

ACIBADEM Health Point: The Future of Healthcare

We believe that everyone deserves access to quality healthcare, which is why we have established multiple branches in strategic locations. Whether you're in need of routine check-ups, specialized treatments, or emergency care, ACIBADEM Health Point is here for you.

Diagnosing fibromuscular dysplasia in the carotid artery involves various methods. These include:

  1. Physical examination: Your doctor may perform a physical examination to assess any noticeable abnormalities in the carotid artery.
  2. Ultrasound: This non-invasive imaging technique uses sound waves to create detailed images of the carotid artery, allowing the doctor to identify any narrowing or other abnormalities.
  3. Magnetic resonance angiography (MRA): MRA uses magnetic fields and radio waves to generate detailed images of blood vessels, providing a comprehensive view of the carotid artery.
  4. Computed tomography angiography (CTA): CTA combines X-ray technology with computer processing to create detailed cross-sectional images of the carotid artery, helping to detect any blockages or abnormal growths.

By understanding the unique characteristics of fibromuscular dysplasia in the carotid artery and utilizing appropriate diagnostic methods, healthcare professionals can accurately identify and assess the condition. This allows for timely and targeted treatment, ultimately improving patient outcomes.

Characteristic FMD Carotid Symptoms FMD Carotid Diagnostic Methods
Abnormal cell growth Dizziness, headaches, blurred vision Physical examination, ultrasound, MRA, CTA
Narrowing of the artery Restricted blood flow to the brain Physical examination, ultrasound, MRA, CTA

The comprehensive diagnostic process for fibromuscular dysplasia in the carotid artery enables healthcare professionals to accurately assess the severity of the condition and determine the most appropriate treatment plan. With early detection and intervention, individuals with FMD can effectively manage their symptoms and reduce the risk of serious complications. Fibromuscular Dysplasia Carotid


ACIBADEM Health Point: Your Health is Our Priority!

ACIBADEM Health Point, we are dedicated to providing exceptional healthcare services to our patients. With a team of highly skilled medical professionals and state-of-the-art facilities, we strive to deliver the highest standard of care to improve the health and well-being of our patients. What sets ACIBADEM Health Point apart is our patient-centered approach. We prioritize your comfort, safety, and satisfaction throughout your healthcare journey. Our compassionate staff ensures that you receive personalized care tailored to your unique needs, making your experience with us as seamless and comfortable as possible.

Symptoms of Carotid Artery Disease

Carotid artery disease, also known as carotid artery stenosis, refers to the narrowing of the carotid arteries that supply blood to the brain. This condition can lead to serious health complications, including stroke, if left untreated. Recognizing the symptoms of carotid artery disease is crucial for early detection and timely intervention. Fibromuscular Dysplasia Carotid

The symptoms of carotid artery disease can vary depending on the severity of the blockage and whether fibromuscular dysplasia is present. Some common signs and symptoms associated with carotid artery disease include:

  • Transient ischemic attacks (TIAs): TIAs, also known as mini-strokes, are brief episodes of decreased blood supply to the brain. They can cause temporary neurological symptoms, such as weakness or numbness in the face, arm, or leg on one side of the body, speech difficulties, or temporary vision loss.
  • Stroke: A stroke occurs when the blood flow to the brain is severely disrupted or completely blocked. This can result in sudden weakness or paralysis on one side of the body, difficulty speaking, loss of coordination, severe headache, or vision problems.
  • Carotid bruit: A carotid bruit is an abnormal sound that can be heard with a stethoscope placed over the carotid artery. It is caused by turbulent blood flow due to narrowing or blockage in the artery.
  • Dizziness or lightheadedness: Reduced blood flow to the brain can cause episodes of dizziness or lightheadedness.
  • Blurry or decreased vision: Carotid artery disease may lead to visual disturbances, such as blurry or decreased vision in one eye.
  • Difficulty swallowing: In some cases, carotid artery disease can cause difficulty swallowing or a feeling of tightness in the throat. Fibromuscular Dysplasia Carotid

If you experience any of these symptoms, it is important to seek immediate medical attention. Prompt evaluation and diagnosis are essential for determining the underlying cause and appropriate management of carotid artery disease, including any necessary treatment for fibromuscular dysplasia. Fibromuscular Dysplasia Carotid

Symptom Description
Transient ischemic attacks (TIAs) Brief episodes of decreased blood supply to the brain, resulting in temporary neurological symptoms like weakness, numbness, speech difficulties, or temporary vision loss.
Stroke Sudden onset of neurological deficits due to severely disrupted or blocked blood flow to the brain.
Carotid bruit An abnormal sound heard over the carotid artery caused by turbulent blood flow due to narrowing or blockage.
Dizziness or lightheadedness Episodes of dizziness or lightheadedness due to reduced blood flow to the brain.
Blurry or decreased vision Visual disturbances, including blurry or decreased vision in one eye.
Difficulty swallowing Difficulty swallowing or feeling of tightness in the throat.

Diagnosis of Carotid Artery Disease

Accurate diagnosis of carotid artery disease is crucial for effective treatment and prevention of complications. To detect and evaluate the presence of fibromuscular dysplasia in the carotid arteries, healthcare professionals may utilize several diagnostic tests and imaging techniques:

1. Carotid Ultrasound:

A carotid ultrasound, also known as Doppler ultrasound, is a non-invasive imaging test that uses sound waves to create detailed images of the carotid arteries. This test can detect any narrowing or blockages in the arteries, allowing doctors to assess the severity of the condition and identify potential areas of fibromuscular dysplasia.

See also  Common Medications Leading to Hyponatremia

2. Magnetic Resonance Angiography (MRA):

MRA is a non-invasive imaging technique that uses magnetic fields and radio waves to produce detailed images of the blood vessels, including the carotid arteries. MRA can provide information about the structure and blood flow in the arteries, helping physicians diagnose fibromuscular dysplasia and assess its impact on the carotid arteries.

3. Computed Tomography Angiography (CTA):

CTA involves the injection of a contrast dye into the bloodstream, followed by a series of X-ray images. These images create detailed cross-sectional views of the carotid arteries, enabling doctors to identify any narrowing or blockages caused by fibromuscular dysplasia. CTA is particularly useful in evaluating the extent and severity of carotid artery disease.

In addition to these imaging tests, healthcare providers may also perform a physical examination, evaluate the patient’s medical history, and assess their risk factors for carotid artery disease. Early diagnosis plays a critical role in preventing complications and initiating appropriate treatment strategies.

Diagnostic Test Advantages Disadvantages
Carotid Ultrasound
  • Non-invasive
  • Painless and safe
  • No radiation exposure
  • Limited ability to assess plaque composition
  • Dependent on operator’s expertise
  • May not provide detailed information in complex cases
Magnetic Resonance Angiography (MRA)
  • Non-invasive
  • No radiation exposure
  • Provides detailed images of blood vessels
  • May not be suitable for patients with certain medical conditions or implanted devices
  • Longer scan time compared to other tests
  • Expensive
Computed Tomography Angiography (CTA)
  • Provides detailed 3D images of blood vessels
  • Can detect small lesions or aneurysms
  • Allows simultaneous assessment of other structures
  • Exposure to radiation
  • Use of contrast dye, which may cause allergic reactions
  • Not recommended for pregnant women

Treatment Options for Carotid Artery Disease

When it comes to treating carotid artery disease, there are a variety of options available depending on the severity of the condition and the specific needs of the patient. Treatment approaches can range from non-invasive methods to surgical interventions. For individuals with fibromuscular dysplasia (FMD) in the carotid arteries, special considerations must be taken into account to ensure optimal outcomes.

1. Medications

In mild cases of carotid artery disease or as a preventive measure, medications may be prescribed to manage the condition. The goal of medication is to control risk factors such as high blood pressure, cholesterol levels, and blood clotting. Common medications include:

  • Antiplatelet drugs: These medications reduce the risk of blood clot formation by preventing platelets from sticking together.
  • Anticoagulants: Typically used for individuals with a higher risk of blood clots, anticoagulants help prevent clotting by thinning the blood.
  • Cholesterol-lowering drugs: These medications help reduce the buildup of plaque in the carotid arteries, slowing down the progression of the disease.

2. Carotid Angioplasty and Stenting

In cases where carotid artery disease is more severe or doesn’t respond well to medication, carotid angioplasty and stenting may be recommended. This minimally invasive procedure involves the insertion of a stent, a small mesh tube, into the narrowed or blocked artery to improve blood flow. The procedure helps widen the artery and keep it open, reducing the risk of stroke.

3. Carotid Endarterectomy

Carotid endarterectomy is a surgical procedure that involves removing the plaque buildup in the carotid artery to restore proper blood flow. This procedure is typically recommended for individuals with severe carotid artery disease or those who have experienced symptoms such as mini-strokes or transient ischemic attacks (TIAs). Carotid endarterectomy can help reduce the risk of stroke and improve overall blood flow.

4. Transcarotid Artery Revascularization (TCAR)

TCAR is a newer, minimally invasive procedure that combines aspects of carotid endarterectomy and carotid angioplasty. During TCAR, a small incision is made at the base of the neck, allowing direct access to the carotid artery. A specialized stent is then inserted to improve blood flow while a filter is used to capture any potential debris. This procedure offers a shorter recovery time and reduced risk of complications compared to traditional surgical approaches.

5. Lifestyle Modifications

In addition to medical interventions and procedures, making certain lifestyle modifications can play a crucial role in managing carotid artery disease. These lifestyle changes include:

  • Quitting smoking: Smoking can contribute to the development and progression of carotid artery disease, so quitting is essential for overall vascular health.
  • Adopting a healthy diet: Eating a diet rich in fruits, vegetables, whole grains, and lean proteins can help control cholesterol levels and reduce the risk of plaque buildup.
  • Exercising regularly: Engaging in regular physical activity can help lower blood pressure, maintain a healthy weight, and promote overall cardiovascular health.
  • Managing stress: Stress management techniques such as meditation, deep breathing exercises, and therapy can help reduce the impact of stress on blood pressure and overall vascular health.

It’s important for individuals with carotid artery disease, including those with fibromuscular dysplasia, to consult with their healthcare provider to determine the most appropriate treatment plan. Each person’s condition is unique, and a personalized approach is necessary to achieve the best possible outcomes.

Treatment Option Procedure Advantages Considerations
Medications No invasive procedure required Control risk factors, preventive measure May not be sufficient for severe disease
Carotid Angioplasty and Stenting Minimally invasive procedure Improved blood flow, reduced stroke risk May not be suitable for all patients
Carotid Endarterectomy Surgical removal of plaque Restores blood flow, reduces stroke risk Higher risk of complications than other procedures
Transcarotid Artery Revascularization (TCAR) Minimally invasive procedure Shorter recovery time, reduced risk of complications Specialized procedure, may not be widely available

Carotid Artery Surgery

Carotid artery surgery is a recommended treatment option for severe cases of fibromuscular dysplasia affecting the carotid artery. This surgical procedure involves removing the buildup of plaque and restoring proper blood flow to the brain. Let’s explore the procedure, potential risks, and recovery process associated with carotid artery surgery.

Procedure

During carotid artery surgery, a vascular surgeon makes an incision in the neck to access the affected carotid artery. The surgeon then carefully removes the plaque buildup and repairs the artery to restore normal blood flow. This procedure may be performed under general anesthesia or with regional anesthesia, depending on the patient’s condition and medical history.

See also  Acidosis Link to Hypokalemia: Facts Uncovered

Potential Risks

While carotid artery surgery is generally safe and effective, like any surgical procedure, it carries certain risks. These risks may include infection, bleeding, blood clots, damage to surrounding structures, and stroke. However, with a skilled surgeon and proper post-operative care, these risks can be minimized.

Recovery Process

The recovery process after carotid artery surgery typically involves a short hospital stay for monitoring and initial recovery. Patients may experience some discomfort and swelling in the neck area, which can be managed with prescribed pain medications and ice packs. It is important for patients to follow their surgeon’s instructions for post-operative care, including taking any prescribed medications, attending follow-up appointments, and gradually resuming normal activities.

Patients are usually advised to avoid strenuous activities, heavy lifting, and driving for a certain period to allow for proper healing. Additionally, it is crucial for patients to adopt a heart-healthy lifestyle by maintaining a balanced diet, exercising regularly, managing stress, quitting smoking (if applicable), and controlling other contributing factors, such as high blood pressure and cholesterol levels.

Overall, carotid artery surgery is a significant and effective intervention for severe fibromuscular dysplasia cases. By addressing the underlying obstruction in the carotid artery, this surgery restores blood flow and reduces the risk of complications, such as stroke.

Benefits of Carotid Artery Surgery Risks of Carotid Artery Surgery
  • Restores proper blood flow to the brain
  • Reduces the risk of stroke
  • Improves cognitive function
  • Alleviates symptoms associated with carotid artery disease
  • Infection
  • Bleeding
  • Blood clots
  • Damage to surrounding structures
  • Stroke

Understanding Carotid Artery Blockage

In individuals with fibromuscular dysplasia (FMD), one common complication that can occur is carotid artery blockage. This occurs when the carotid arteries, which supply blood to the brain, become partially or completely obstructed. The blockage can lead to reduced blood flow, potentially resulting in various symptoms and complications.

Causes of Carotid Artery Blockage

The development of carotid artery blockage can be attributed to several factors, including:

  • Atherosclerosis: The build-up of plaque within the arteries, which can eventually block blood flow.
  • Fibromuscular dysplasia: The abnormal growth of cells within the arterial walls, leading to narrowing and potential blockage.
  • Blood clots: The formation of blood clots within the carotid arteries, impeding blood flow.

Symptoms of Carotid Artery Blockage

The symptoms experienced by individuals with carotid artery blockage can vary, depending on the extent of the blockage and the collateral circulation. Common symptoms include:

  • Transient ischemic attacks (TIAs): Brief episodes of reduced blood flow to the brain, resulting in temporary neurological symptoms, such as weakness, numbness, or difficulty speaking.
  • Stroke: A more severe manifestation of carotid artery blockage, resulting in a sudden loss of brain function, typically accompanied by paralysis, difficulty speaking, or altered consciousness.
  • Carotid bruits: Abnormal sounds heard during a physical examination of the neck caused by turbulent blood flow through the narrowed carotid artery. Fibromuscular Dysplasia Carotid

It is crucial to seek immediate medical attention if any of these symptoms are experienced, as early intervention can significantly improve outcomes. Fibromuscular Dysplasia Carotid

Potential Consequences of Carotid Artery Blockage

Untreated carotid artery blockage can have serious consequences, including:

  • Progression of symptoms: Without timely treatment, carotid artery blockage can lead to a gradual worsening of symptoms, increasing the risk of more severe strokes.
  • Complete blockage: In some cases, the blockage can become complete, cutting off blood supply to the brain and potentially leading to a massive stroke or even death.
  • Reduced quality of life: The symptoms associated with carotid artery blockage can significantly impact an individual’s daily functioning and overall quality of life.

By understanding the causes, symptoms, and potential consequences of carotid artery blockage, individuals with fibromuscular dysplasia can take proactive steps to manage their condition and reduce the risk of complications.

Maintaining Vascular Health

Fibromuscular dysplasia in the carotid arteries requires ongoing attention and care to maintain vascular health. By making certain lifestyle modifications, taking prescribed medications, and undergoing regular monitoring, individuals with this condition can effectively manage their symptoms and reduce the risk of complications.

Lifestyle Modifications

To support vascular health, it is crucial to adopt a healthy lifestyle. This includes:

  • Maintaining a balanced diet that is low in sodium, saturated fats, and cholesterol
  • Incorporating regular exercise into your routine, such as walking, swimming, or cycling
  • Avoiding tobacco products and minimizing alcohol consumption
  • Managing stress through techniques like meditation, deep breathing exercises, or engaging in hobbies

Medications

In some cases, medication may be prescribed to manage symptoms and prevent further progression of fibromuscular dysplasia in the carotid arteries. Common medications used include:

Medication Purpose
Antiplatelet drugs To reduce the risk of blood clot formation
Antihypertensive drugs To control high blood pressure
Cholesterol-lowering drugs (statins) To manage high cholesterol levels

Regular Monitoring

Regular monitoring is essential for assessing the progress of fibromuscular dysplasia in the carotid arteries and ensuring appropriate management. This may involve:

  • Regular visits to your healthcare provider for physical examinations and blood pressure checks
  • Periodic imaging tests, such as ultrasounds or angiograms, to assess the condition of the carotid arteries
  • Monitoring of cholesterol levels and other relevant blood tests

By diligently following these lifestyle modifications, taking prescribed medications, and participating in regular monitoring, individuals with fibromuscular dysplasia in the carotid arteries can take control of their vascular health and reduce the potential risks associated with this condition.

Available Treatments for Fibromuscular Dysplasia

When it comes to treating fibromuscular dysplasia (FMD) in the carotid arteries, there are several options available. The choice of treatment depends on the severity of the condition and the individual patient’s needs. Here, we will explore these treatment options, discussing the benefits and risks of each approach, arming you with the information you need to make an informed decision alongside your healthcare provider.

Medical Management

In less severe cases of FMD in the carotid arteries, medical management may be the recommended approach. This involves medication to manage symptoms, lower blood pressure, and reduce the risk of complications such as strokes:

  • Antihypertensive medications: These drugs help control high blood pressure, reducing the strain on the carotid arteries.
  • Antiplatelet medications: Medications such as aspirin or clopidogrel may be prescribed to reduce the risk of blood clots forming in the carotid arteries.
See also  High WBC Count & Creatinine Levels

Angioplasty and Stenting

In cases where FMD in the carotid arteries is causing significant narrowing or blockage, angioplasty with stenting may be recommended. This minimally invasive procedure involves the following steps:

  1. A balloon-tipped catheter is threaded through a blood vessel to the site of the blockage.
  2. The balloon is inflated, widening the narrowed artery and improving blood flow.
  3. A stent, a small mesh tube, is then inserted to keep the artery open and prevent further narrowing or blockage.

This procedure has shown positive results in restoring normal blood flow and reducing the risk of strokes associated with carotid artery disease.

Carotid Endarterectomy

In more severe cases of FMD in the carotid arteries, carotid endarterectomy may be recommended. This surgical procedure involves removing the plaque and diseased inner lining of the carotid artery to restore normal blood flow. The steps involved in a carotid endarterectomy are as follows:

  1. An incision is made in the neck to access the carotid artery.
  2. The diseased segment of the artery is carefully removed.
  3. The artery is then repaired, either by sewing the cut ends together or by using a synthetic graft.

Carotid endarterectomy has shown to be effective in improving blood flow and reducing the risk of strokes caused by carotid artery disease.

It is important to note that the choice of treatment for FMD in the carotid arteries is highly individualized. Your healthcare provider will evaluate your specific case and discuss the most appropriate treatment options for you. Together, you can make an informed decision that takes into account the benefits, risks, and outcomes associated with each treatment approach. Fibromuscular Dysplasia Carotid

Treatment Option Benefits Risks
Medical Management – Controls blood pressure
– Reduces the risk of complications
– Potential side effects of medication
– May not be effective for severe cases
Angioplasty and Stenting – Minimally invasive
– Restores normal blood flow
– Reduces stroke risk
– Possible complications during the procedure
– Risk of re-narrowing of the artery
Carotid Endarterectomy – Removes plaque and restores blood flow
– Reduces stroke risk
– Potential surgical complications
– Requires general anesthesia

Seeking Expert Care at Acibadem Healthcare Group

When it comes to fibromuscular dysplasia in the carotid arteries, choosing the right healthcare provider is crucial. At Acibadem Healthcare Group, we specialize in providing expert care and personalized treatment options for individuals with this condition. Our experienced team of medical professionals is dedicated to ensuring optimal outcomes for every patient. Fibromuscular Dysplasia Carotid

At Acibadem Healthcare Group, we understand the unique challenges associated with fibromuscular dysplasia in the carotid arteries. Our multidisciplinary approach combines advanced diagnostic techniques, state-of-the-art technolog y, and innovative treatment options. We believe in delivering compassionate care that takes into account each patient’s specific needs and preferences. Fibromuscular Dysplasia Carotid

With a reputation for excellence and a commitment to patient-centered care, Acibadem Healthcare Group is a trusted name in healthcare. Our comprehensive services range from accurate diagnosis and customized treatment plans to ongoing monitoring and support. We strive to empower our patients with the knowledge and resources they need to manage their condition effectively. Fibromuscular Dysplasia Carotid

 

FAQ

What is fibromuscular dysplasia (FMD) in the carotid artery?

Fibromuscular dysplasia (FMD) is a rare condition that affects the walls of the carotid arteries, leading to abnormalities in their structure. These abnormalities can cause narrowing (stenosis), blockages, or weakening of the arteries, compromising blood flow to the brain and increasing the risk of stroke.

What are the symptoms of fibromuscular dysplasia in the carotid artery?

The symptoms of fibromuscular dysplasia in the carotid artery can vary and may include headaches, pulsatile tinnitus (ringing in the ears), dizziness, neck pain, and high blood pressure. In more severe cases, individuals may experience transient ischemic attacks (mini-strokes) or strokes.

How is fibromuscular dysplasia in the carotid artery diagnosed?

Fibromuscular dysplasia in the carotid artery is typically diagnosed through various imaging tests, such as Doppler ultrasound, CT angiography, or magnetic resonance angiography (MRA). These tests help visualize the structure and blood flow in the carotid arteries, allowing for accurate diagnosis.

What are the available treatment options for fibromuscular dysplasia in the carotid artery?

The treatment options for fibromuscular dysplasia in the carotid artery depend on the severity of the condition and the individual's overall health. Non-invasive approaches, such as medication management and lifestyle modifications, may be recommended for mild cases. In more severe cases, surgical interventions, such as carotid artery angioplasty or bypass surgery, may be necessary to restore proper blood flow.

What is carotid artery surgery?

Carotid artery surgery, also known as carotid endarterectomy, is a surgical procedure used to remove the plaque buildup in the carotid arteries. This procedure helps restore normal blood flow and reduce the risk of stroke in individuals with carotid artery disease, including those with fibromuscular dysplasia.

What are the symptoms of carotid artery blockage?

Carotid artery blockage, which can occur as a complication of fibromuscular dysplasia, may cause symptoms such as sudden weakness or numbness on one side of the face or body, difficulty speaking, vision problems, and severe dizziness. These symptoms require immediate medical attention, as they may indicate an imminent stroke.

How can individuals with fibromuscular dysplasia in the carotid arteries maintain vascular health?

Managing vascular health involves various strategies, including quitting smoking, maintaining a healthy weight, exercising regularly, managing blood pressure and cholesterol levels, and following a nutritious diet. Regular check-ups and medication management, as prescribed by a healthcare professional, are also essential.

What are the available treatments for fibromuscular dysplasia in the carotid artery?

The available treatments for fibromuscular dysplasia in the carotid artery include medication management to control blood pressure and prevent blood clots, angioplasty with or without stenting to widen the narrowed arteries, and surgical interventions such as bypass surgery. The most suitable treatment option depends on the individual's specific condition.

Why should I seek expert care at Acibadem Healthcare Group for fibromuscular dysplasia in the carotid arteries?

Acibadem Healthcare Group specializes in providing comprehensive care for individuals with fibromuscular dysplasia in the carotid arteries. Our experienced medical team uses state-of-the-art diagnostic techniques and offers a wide range of treatment options, including minimally invasive procedures and advanced surgical interventions, to ensure optimal outcomes for our patients.


ACIBADEM Healthcare Group Hospitals and Clinics

With a network of hospitals and clinics across 5 countries, including 40 hospitals, ACIBADEM Healthcare Group has a global presence that allows us to provide comprehensive healthcare services to patients from around the world. With over 25,000 dedicated employees, we have the expertise and resources to deliver unparalleled healthcare experiences. Our mission is to ensure that each patient receives the best possible care, supported by our commitment to healthcare excellence and international healthcare standards. Ready to take the first step towards a healthier future? Contact us now to schedule your Free Consultation Health session. Our friendly team is eager to assist you and provide the guidance you need to make informed decisions about your well-being. Click To Call Now !

*The information on our website is not intended to direct people to diagnosis and treatment. Do not carry out all your diagnosis and treatment procedures without consulting your doctor. The contents do not contain information about the therapeutic health services of ACIBADEM Health Group.