The HINTS exam, or Head Impulse, Nystagmus, Test of Skew, is a bedside vestibular examination that can be used to assess for peripheral vestibular dysfunction. It is a simple, quick, and non-invasive exam that can be performed in a variety of settings, including the office, the emergency department, and the inpatient setting.
- What is the HINTS exam?
- Why is the HINTS exam important?
- How to prepare for the HINTS exam
- The HINTS exam step-by-step
- Common HINTS exam mistakes to avoid
- HINTS exam tips for US audiences
- HINTS exam resources for US audiences
- Real-world examples of HINTS exam use
- How to interpret your HINTS exam results
- The future of the HINTS exam
- Conclusion
- FAQ
What is the HINTS exam?
The HINTS exam consists of three parts:
- Head impulse test: This test assesses the vestibular ocular reflex (VOR), which is the reflex that helps us maintain gaze stability during head movement. To perform the head impulse test, the examiner quickly rotates the patient’s head in a horizontal plane. The patient is asked to keep their eyes focused on the examiner’s nose. If the VOR is intact, the patient’s eyes will remain fixed on the examiner’s nose. However, if the VOR is impaired, the patient’s eyes will move in the opposite direction of the head movement.
- Nystagmus: Nystagmus is an involuntary rhythmic oscillation of the eyes. It can be caused by a variety of conditions, including vestibular disorders, neurological disorders, and drug toxicity. To assess for nystagmus, the examiner asks the patient to look in different directions, including straight ahead, up, down, and to the sides. The examiner also asks the patient to perform head shaking and rapid alternating gaze. If nystagmus is present, the examiner will note the direction, frequency, and amplitude of the eye movements.
- Test of skew: The test of skew assesses the vertical alignment of the eyes. To perform the test of skew, the examiner asks the patient to look straight ahead. The examiner then observes the position of the patient’s pupils. If the pupils are aligned vertically, then the test of skew is negative. However, if the pupils are not aligned vertically, then the test of skew is positive.
Why is the HINTS exam important?
The HINTS exam is important because it can help healthcare professionals quickly and accurately diagnose peripheral vestibular disorders. Peripheral vestibular disorders are a common cause of dizziness, and they can be caused by a variety of factors, including infections, inflammation, and trauma.
The HINTS exam is important for a number of reasons:
- It is a very sensitive and specific test, which means that it is very good at identifying patients with peripheral vestibular disorders and ruling out patients without peripheral vestibular disorders.
- It is a bedside test, which means that it can be performed in a variety of settings, including the office, the emergency department, and the inpatient setting.
- It is a quick and non-invasive test, which means that it can be performed with minimal discomfort to the patient.
- It is a relatively inexpensive test, which makes it accessible to a wide range of patients.
How to prepare for the HINTS exam
The HINTS exam is a bedside vestibular examination, so there is no specific preparation required. However, there are a few things that you can do to make the exam more comfortable and accurate:
- Avoid caffeine and alcohol before the exam. Caffeine and alcohol can interfere with the vestibular system, which can make the exam results less accurate.
- Remove any glasses or contact lenses before the exam. This will allow the examiner to better see your eyes.
- If you have long hair, tie it back before the exam. This will keep your hair out of your face and make it easier for the examiner to see your eyes.
- Be prepared to follow the examiner’s instructions. The examiner will ask you to look in different directions and perform certain head movements. It is important to follow the examiner’s instructions carefully so that the exam results are accurate.
The HINTS exam step-by-step
The HINTS exam is a bedside vestibular examination that consists of three parts:
- Head impulse test: This test assesses the vestibular ocular reflex (VOR), which is the reflex that helps us maintain gaze stability during head movement.
- Nystagmus test: This test assesses for nystagmus, which is an involuntary rhythmic oscillation of the eyes.
- Test of skew: This test assesses the vertical alignment of the eyes.
Head impulse test
- Position the patient sitting with their head upright.
- Ask the patient to focus their gaze on your nose.
- Quickly rotate the patient’s head to the right by about 20 degrees.
- Observe the patient’s eyes. If the VOR is intact, the patient’s eyes will remain fixed on your nose. However, if the VOR is impaired, the patient’s eyes will move in the opposite direction of the head movement.
- Repeat steps 2-4, rotating the patient’s head to the left.
Nystagmus test
- Ask the patient to look straight ahead.
- Observe the patient’s eyes for nystagmus.
- Ask the patient to look in different directions, including up, down, and to the sides.
- Ask the patient to perform head shaking and rapid alternating gaze.
- If nystagmus is present, note the direction, frequency, and amplitude of the eye movements.
Test of skew
- Ask the patient to look straight ahead.
- Observe the position of the patient’s pupils. If the pupils are aligned vertically, then the test of skew is negative. However, if the pupils are not aligned vertically, then the test of skew is positive.
Common HINTS exam mistakes to avoid
- Not properly positioning the patient. The patient should be sitting upright with their head held still. If the patient’s head is not properly positioned, the results of the exam may be inaccurate.
- Not rotating the patient’s head quickly enough. The head impulse test should be performed quickly in order to assess the vestibular ocular reflex (VOR). If the head is not rotated quickly enough, the results of the test may be inaccurate.
- Not observing the patient’s eyes closely. The examiner should carefully observe the patient’s eyes for nystagmus. If the examiner is not careful, they may miss subtle signs of nystagmus.
- Not noting the position of the patient’s pupils. The examiner should note the position of the patient’s pupils when performing the test of skew. If the examiner does not note the position of the patient’s pupils, they may miss a positive test result.
- Not correlating the results of the HINTS exam with the patient’s clinical history and physical examination. The HINTS exam is just one part of the diagnostic process. It is important to correlate the results of the HINTS exam with the patient’s clinical history and physical examination in order to make an accurate diagnosis.
HINTS exam tips for US audiences
- Be aware of the different types of vestibular disorders. The HINTS exam can be used to diagnose a variety of vestibular disorders, including benign paroxysmal positional vertigo (BPPV), vestibular neuritis, labyrinthitis, and Meniere’s disease. Knowing about the different types of vestibular disorders can help you to better understand your symptoms and the results of the HINTS exam.
- Discuss your symptoms with your doctor before the exam. This will help your doctor to better interpret the results of the exam. Be sure to tell your doctor about any other medical conditions you have and any medications you are taking.
- Be prepared to follow the examiner’s instructions carefully. The HINTS exam is a simple exam, but it is important to follow the examiner’s instructions carefully so that the results are accurate.
- Don’t be afraid to ask questions. If you have any questions about the exam or your results, please don’t hesitate to ask your doctor.
HINTS exam resources for US audiences
- American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS): The AAO-HNS is a professional organization that represents otolaryngologists-head and neck surgeons. The AAO-HNS website has a section on vestibular disorders, which includes information on the HINTS exam.
- American Society of Neurotology (ASN): The ASN is a professional organization that represents neurotologists. The ASN website has a section on vestibular disorders, which includes information on the HINTS exam.
- Vestibular Disorders Association (VEDA): VEDA is a nonprofit organization that provides support and information to people with vestibular disorders. The VEDA website has a section on the HINTS exam, which includes information on how to prepare for the exam and what to expect.
- National Institute on Deafness and Other Communication Disorders (NIDCD): The NIDCD is a research institute that studies hearing, deafness, and other communication disorders. The NIDCD website has a section on vestibular disorders, which includes information on the HINTS exam.
Real-world examples of HINTS exam use
Example 1:
A 62-year-old man presents to the emergency department with complaints of dizziness and vertigo. The patient’s dizziness is worse when he changes head position. The HINTS exam reveals a positive head impulse test to the right and nystagmus to the left. The patient is diagnosed with vestibular neuritis and is discharged home with instructions to follow up with his primary care physician.
Example 2:
A 48-year-old woman presents to her primary care physician with complaints of dizziness and vertigo. The patient’s dizziness is worse when she is lying down and when she gets up from a chair. The HINTS exam reveals a positive test of skew. The patient is diagnosed with benign paroxysmal positional vertigo (BPPV) and is treated with the Epley maneuver.
Example 3:
A 75-year-old man presents to the neurologist with complaints of dizziness and ataxia. The patient’s dizziness is constant and is worse when he is walking. The HINTS exam reveals a positive head impulse test to the right and nystagmus to the left. The patient is diagnosed with a stroke in the cerebellum.
How to interpret your HINTS exam results
The interpretation of your HINTS exam results depends on the results of the three parts of the exam: the head impulse test, the nystagmus test, and the test of skew.
Head impulse test
- A positive head impulse test means that the vestibular ocular reflex (VOR) is not working properly. The VOR is a reflex that helps us maintain gaze stability during head movement. If the VOR is not working properly, the eyes will not move in the correct direction to compensate for head movement.
- A negative head impulse test means that the VOR is working properly.
Nystagmus test
- Nystagmus is an involuntary rhythmic oscillation of the eyes. It can be caused by a variety of conditions, including vestibular disorders, neurological disorders, and drug toxicity.
- The direction of the nystagmus can help to determine the location of the lesion in the vestibular system. For example, nystagmus that beats towards the affected ear is suggestive of a peripheral vestibular disorder, such as vestibular neuritis.
- The frequency and amplitude of the nystagmus can also be helpful in determining the severity of the lesion.
Test of skew
- A positive test of skew means that there is a vertical misalignment of the eyes. This can be caused by a variety of conditions, including central vestibular disorders, such as a stroke in the cerebellum, and peripheral vestibular disorders, such as Meniere’s disease.
- A negative test of skew means that there is no vertical misalignment of the eyes.
The future of the HINTS exam
The HINTS exam is a valuable tool for diagnosing peripheral vestibular disorders, but it has some limitations. For example, the HINTS exam is not very sensitive for detecting central vestibular disorders. Additionally, the HINTS exam can be difficult to perform in patients with neck pain or spinal cord injuries.
Researchers are working on new technologies that could improve the sensitivity and specificity of the HINTS exam. For example, some researchers are developing new wearable devices that can track eye movements and head movements more accurately. Additionally, some researchers are developing new software that can analyze the results of the HINTS exam more objectively.
Conclusion
The HINTS exam is a simple, quick, and non-invasive bedside exam that can be used to assess for peripheral vestibular dysfunction. It is a valuable tool for healthcare professionals who treat patients with dizziness.
The HINTS exam consists of three parts:
- Head impulse test
- Nystagmus test
- Test of skew
The results of the HINTS exam can be used to help diagnose a variety of peripheral vestibular disorders, including benign paroxysmal positional vertigo (BPPV), vestibular neuritis, labyrinthitis, and Meniere’s disease. The HINTS exam can also be used to help differentiate between central and peripheral vestibular disorders.
If you have any questions about the HINTS exam, please talk to your doctor.
Conclusion
The HINTS exam is a valuable tool for diagnosing peripheral vestibular disorders. It is a simple, quick, and non-invasive exam that can be performed in a variety of settings. The HINTS exam can help healthcare professionals to make a more accurate diagnosis, avoid unnecessary testing and procedures, develop a more effective treatment plan, and monitor the patient’s progress over time.
If you are experiencing dizziness, it is important to see a healthcare provider to get a diagnosis and treatment plan. The HINTS exam is an important tool that can help your healthcare provider to accurately diagnose your condition and develop an effective treatment plan.
FAQ's?
It has been found that a positive HINTS exam has a high sensitivity and specificity for the existence of a central source of vertigo. The HINTS exam is only utilized on a subgroup of patients who have: Vertigo that lasts for hours or days. Nystagmus.
An aberrant head impulse test (with a corrective saccade), nystagmus that does not shift direction on eccentric gaze, and a negative test of skew deviation should all be present in an HINTS exam consistent with peripheral vertigo.
The HINTS plus evaluation should be performed only on patients who have persistent vertigo and spontaneous nystagmus. The Dix-Hallpike test should be performed only on patients who have brief episodes of vertigo and no spontaneous or gaze-evoked nystagmus.
Background Acute vestibular syndrome (AVS) is characterized by constant dizziness and can be caused by a benign inner ear condition or a stroke. Within the first 24 hours, the head impulse-nystagmus-test of skew (HINTS) bedside examination is more sensitive than brain MRI in detecting stroke as the origin of AVS.
