Introduction
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative infectious
agent of coronavirus disease 2019 (COVID-19), which is considered a pandemic by the
World Health Organization (WHO). Genome sequencing led to its classification as a
new genus of betacoronavirus. Viral features that enabled it to attain pandemic proportions
include its high rate of transmission and the lack of specific immunity; it took over
a year before specific vaccines became available.[1 ]
[2 ]
[3 ]
[4 ]
In an attempt to decrease the transmission rate of the virus, the World Health Organization
(WHO) emphasizes the importance of social distancing,[5 ] social isolation,[6 ]
[7 ] and quarantine.[5 ]
[6 ] These non-pharmacological measures aim to protect everyone, especially high-risk
groups.[6 ]
These non-pharmacological measures have played an important role in curbing the spread
of the disease, though they have also had negative economic and social consequences.
Social distancing and isolation have also had unintended adverse effects on public
health. Another area of concern is the low rate of diagnosis of previously-frequent
cardiovascular, neurological and oncological conditions. Furthermore, many people
avoid going to health centers and hospitals for fear of being infected by the virus,
further worsening this adverse effect.[8 ]
[9 ]
These direct and indirect consequences of the pandemic, such as prolonged time at
home, lack of physical activity, psycho-emotional disturbances, and poor eating habits,
can have adverse effects on health,[10 ]
[11 ]
[12 ] including diseases of the vestibular system.
Of the various vestibular diseases, vestibular hypofunction (VH) is one of the most
prevalent, often underlying vestibular neuritis and labyrinthitis, which represent
about 630 thousand cases per year in specialized clinics.[13 ] Vestibular hyperfunction can compromise both ears and in this situation it is estimated
that its prevalence is of 28 per every 100 thousand people.[14 ]
Vestibular hyperfunction is characterized by a decrease in the functioning of the
vestibular system, either by deterioration of the vestibular nerve, of structures
of the central nervous system, or of the labyrinth; this dysfunction can be unilateral
or bilateral.[15 ]
[16 ]
The clinical picture may vary, depending on the severity of the involvement and the
topography of the lesion; however, most of the time, the patient complains of dizziness
during movements, nausea, decreased visual acuity during head movements, and instability
during walking.[17 ] Vestibular hyperfunction is associated with diminished of quality of life; its causes
can be toxic (such as, ototoxic medications), vascular (labyrinthine infarct), tumoral
(such as, vestibular schwannoma), labyrinthine disorders (such as, Ménière disease),
and viral (vestibular neuritis), and it tends to be more frequent in the elderly.[18 ]
[19 ]
Vestibular rehabilitation is considered safe and effective to manage patients with
VH, and it is included in most of the clinical guidelines for vestibular disorders.[13 ]
The indirect effects of spending more time at home, such as hypomobility, psycho-emotional
stress, poor diet, and low exposure to sunlight increase the risk of vestibular disorders.
Under regular (non-pandemic) conditions, the evaluation of patients with VH includes
a detailed physical examination, which requires close physical contact between the
examiner and the patient. This presents a risk in the current COVID-19 pandemic; therefore,
the regular neurotological consultations and physical rehabilitation have often been
deferred.
For this reason, teleconsultation is presented as an efficient and safe alternative,
which deploys technology to provide remote health services, virtually connecting the
examiner and the patient, potentially with a broad geographic reach, offering the
possibility of delivering educational material, preventative counseling, diagnosis,
and treatment.[20 ]
[21 ]
[22 ]
In view of the need for social distancing due to COVID-19 and the high prevalence
of VH, the adaptation of the neurotological practice to a telemedicine format, especially
regarding evaluations, is relevant, for ti reduces the risks of bidirectional contamination.
There is emerging evidence that the effectiveness of telecare is similar to that of
face-to-face services for specific diseases in particular specialties.
Discussion
In the current global context, some health care facilities continue to offer in-person
assistance to patients with suspected vestibulopathies, though with a reduced volume
of patients. Teleconsultation is probably a safe and effective tool to carry out patient
evaluations, although the evidence for this remains limited and indirect.
The technology deployed for teleconsultation is not new in itself, but may be unfamiliar
to neurotology professionals; these practitioners may require guidance or training
in how to conduct a remote physical examination. The requirements for social distancing
and limitations to physical contact imposed by the COVID-19 pandemic have forced health
care practitioners to improve, and sometimes to create, strategies for the remote
examination and treatment of patients with vestibular dysfunction.[29 ]
[30 ]
[31 ]
Bearing this in mind, we propose a strategy to provide this kind of care through the
following steps:
Step 1: technical conditions and limitations
To enable teleconsultation, it is necessary to use a digital device, preferably a
smartphone, as suggested in the present study, in order to facilitate the execution
of certain tests, and to have a videoconferencing system ([Fig. 1 ]).
Fig. 1 Teleconsultation – videoconference system.
The device must have an application with at least a videoconferencing function, and
those that are formally guided by scientific and governmental guidelines are: WhatsApp,
Zoom for Healthcare, Facetime, Facebook Messenger, Skype, Microsoft Teams, Viber,
Imo, Line, Hangouts, Snapchat, Jus Talk, Zoom, Discord, and Houseparty.[32 ]
[33 ] These applications offer greater privacy and patient security.[34 ]
It is important to note that the policies and regulations for teleconsultation assistance
may vary between countries. However, there is broad agreement that digital platforms
that rely on open social networks are not recommended. It is desirable that the application
guarantees privacy, allows data archiving, and offers greater data security to the
professional and the patient ([Fig. 1 ]).
Even if the technology and software are appropriate, authorization is still necessary,
according to local regulations. The patient must always be informed (in advance of
the teleconsultation) about the characteristics of the procedures in order to grant
their informed consent.
Step 2: establishing the exam environment
For the start of the teleconsultation, it may be helpful if a relative or caregiver
is present, although this is not mandatory. The presence of a family member or caregiver
can facilitate the recording of eye movements and the performance of some tests, and
will also provide greater patient safety, especially during the initial encounter,
in case the patient does not tolerate the examination well.
The assistant or the patients themselves will transmit the image of the eyes, as directed,
keeping them wide open. It is important that the location chosen for the teleconsultation
has good lighting and a bed, usually the patient's bed. The highest video resolution
available should be used.
Step 3: protocol approach for remote diagnosis
As shown in [Figure 2 ], the teleconsultation protocol for patients with suspected VH is divided into several
stages. First, initial contact is established with the patient and his or her assistant;
if applicable, the advantages, disadvantages, and limitations of remote consultation
should be clarified, and, after the patient's voluntary informed consent is obtained,
the examination environment should be established (step 2). We then advance to step
3a (collection of personally identifiable information); in this step, data such as
full name, date of birth, address, profession, and any other information relevant
to the diagnostic process is collected.
Fig. 2 Teleconsultation guidelines for the diagnosis of vestibular hypofunction.
Dizziness is a common symptom of COVID-19 infection, including acute vestibular hypofunction;
therefore, associated symptoms of the infection (dyspnea, fever, headache etc.) must
be assessed early in the encounter.[35 ]
Then, step 3b, anamnesis, begins by asking guiding questions to build the patient's
current medical history. At this stage, information is also collected on the medications
used, previous diagnoses, and lifestyle habits. Contraindications for neck movement
must be stated.
We suggest that anamnesis follow the time, trigger, target examination (TiTRaTe) approach,
which emphasizes the importance of defining the onset and duration of symptoms, what
triggers them (activation), and so proceed with the otoneurological evaluation similar
to the one made at the bedside. The TiTRaTe approach seeks to classify the information
collected into an acute, episodic or chronic vestibular syndrome.[36 ]
Once the diagnostic hypothesis of vestibular hypofunction has been proposed, step
3c (evaluation: functional tests) should be performed for confirmation or exclusion.
Similar to the bedside evaluation, in the teleconsultation model the evaluation is
divided into five stages: I) static evaluation (head tilt, saccadic intrusions, spontaneous
nystagmus); II) evaluation of the eyes only, without moving the head (spontaneous
nystagmus, gaze -voked nystagmus, alternating cover test, saccadic movements, ocular
pursuit, optokinetic nystagmus); III) combined evaluation of the vestibular and visual
systems (suppression of the vestibular ocular reflex); IV) the Romberg test, and tests
of gait and coordination, among others; V) Otolitic Evaluation.[37 ] Other tests can also be included, depending on the evaluation of the risk of fall,
such as: IV) the Romberg test, and tests of gait and coordination, among others.[37 ]
In step 3c (stages I to V), the examiner should instruct the patient to position the
camera so that the eye is in the center of the video frame. In order to acquire close-up
images of the eye in sufficient detail, it may be necessary to bring the camera closer
to the patient's eye, or to use the camera's zoom function (if available). The patient
should always keep his or her eyes open. Another alternative is for the assistant
to operate the device or the patient to use a smartphone stand.
As in the face-to-face evaluation, during the teleconsultation, the examiner should
explain the procedure to the patient before performing it, so that the tests can be
carried out smoothly. The tests related to to step 3c (stages I and II) should be
carried out similarly to the face-to-face examination. The examiner should use the
edges of the screen (“device screen boundary”) to estimate horizontal and vertical
eye movements. It is recommended that the examiner limit the patient's eye movements
as much as possible for the sake of a better analysis, through the resources of the
application itself or the screen recording available on the computer or in another
application.
Recently, the American Academy of Neurology developed and disseminated a neurological
examination model for teleconsultations.[38 ] Although the neurotological examination was not directly included, the model contains
some of the evidence from step 3c (stages I and II), and is a relevant tool to identify
signs of central lesions for remote diagnosis.[39 ]
For step 3c (stage III), the examiner should start with the vestibulo-ocular reflex
(VOR), guiding the patient to make horizontal rotational movements of the head from
10° to 20°, slowly, keeping the eye fixed on the object presented or at the tip of
the nose. The examiner should then instruct the patient to make vertical head movements
(with neck flexion and extension), at the same angle and speed as the horizontal ones,
and maintaining visual fixation as instructed.[40 ] Then, the patient should place a target before himself or herself (usually the thumb
held at arm's length), at eye level, while still maintaining the same angles and speed
as the slow VOR test, to perform the horizontal and vertical movements; however, then,
the head and the objective must move in the same direction (for the suppression of
the visual fixation). This test can also be performed with block movements.[41 ] The examiner should always guide the patient/assistant to keep the device static,
appropriately positioned, with the eyes open, and zoom in when necessary, to visualize
any eye movements (such as the appearance of saccadic intrusions).
Step 3c (stage III) is the head impulse test. In an in-person evaluation, this would
be performed by the examiner as a passive movement, whose diagnostic sensitivity is
higher. In contrast, teleconsultations require an active head movement (that is, the
patient executes the maneuver himself or herself). This active method is less sensitive
than the passive one, but, in cases of unilateral vestibular hypofunction, it can
still elicit corrective refixation saccades during the impulse directed towards the
side of the lesion.[40 ] The usual contraindications for the passive head impulse test also apply when it
is performed actively (for example, known cervical spine disease, known vertebral
artery occlusive disease or dissection etc.).
If, during step 2, there are complaints related to changes in static and/or dynamic
equilibrium, step 3c (stage IV) can be used. At this stage, the Romberg test, an analysis
of the gait through a timed-up-and-go (TUG) test, for example, and a coordination
test, among others,[37 ] can be applied. The patient will need an assistant near him or her in order to prevent
falls, and should do this in a suitable space, such as a hallway or room of sufficient
length. The examiner will evaluate the pattern of oscillations to classify them as
normal or pathological, as well as whether the results suggest peripheral or central
deficits. In step 3c (stage IV), the device is guided by the helper. The examination
of the coordination is also very important for the exclusion or confirmation of suspected
cerebellar pathologies, and can be carried out during the teleconsultation, since
these are “active” examination techniques (that is, requiring voluntary action on
the part of the patient). Some tests in remote format have been evaluated by the American
Academy of Neurology.[38 ]
[39 ]
The otoneurology consultation can include the subjective visual vertical test and
the head heave test, which assess the function of the otolithic organs; these are
less frequently discussed, but are no less relevant.[42 ]
[43 ] For step 3c (stage V), we suggest that the examiner present a line via the application
on the phone, or ask the patient to have the application showing the line on his device.
Thus, the patient should be able to guide the examiner to position the device so that
he / she considers that the visualized line is totally vertical (0°), or, if he /
she is doing it on his / her own device, he / she will follow the examiner's instructions
and show the result obtained by the application.
For this evaluation, the application Visual Vertical can also be used. Developed by
Jacob Brodsky, this application has been shown to be effective in children, adolescents
and adults, and is well adapted to be used in teleconsultations. Instead of having
to attach the smartphone to the bottom of a bucket, this application simply displays
a line on the screen, and the patient guides the examiner until he /she perceives
it to be vertical.[42 ] To optimize the test's sensitivity, the examiner may request that the patient perform
this portion of the exam in the darkest environment available.
The head heave Test in teleconsultations is performed actively. It is advised that
the patient maintain the vision fixed on a point presented by the examiner and perform
linear movements (that is, translational rather than rotational) from the center to
the right and from the center to the left, with low amplitude, but high velocity.
The patient will report symptoms, and the examiner should monitor for the presence
of corrective saccades that indicate otolithic dysfunction.[43 ] This test is considered by many examiners to be difficult to perform during face-to-face
care. It is up to the examiner to judge the feasibility of the execution in the remote
format with a given patient.
After the clinical diagnosis of unilateral or bilateral vestibular hypofunction due
to peripheral or central pathologies, the practitioner must proceed with the determination
of the etiology. In some cases, additional evaluations may require laboratory testing
or imaging exams. As a treatment option, vestibular physiotherapy can also be performed
virtually, using the videoconference system, mainly because it is usually performed
in a non-instrumented and active way. Medications, if appropriate, can be prescribed
by the physician. When the examination is performed by a non-prescribing professional,
the patient must be referred.[28 ]
Evaluations by teleconsultation have substantial limitations; however, they may be
an efficient alternative in specific situations. If, after completion, the conclusion
is unrevealing, the examiner may still suggest in-person instrumented vestibular testing
in the office. However, it is important to highlight that the previous evaluation
by teleconsultation would reduce the length of stay and the number of patients in
the clinic, since most of the examinations would have already been performed.
If the internet connection is poor
To perform step 3, it is important that both the patient and the examiner have good
internet connection, in order to provide sufficient spatial and temporal resolution
for video observation. In this regard, several complications may arise: i) internet
failures can occur; ii) lack of ability to perform some commands live; or iii) maybe
the patient initially had an adequate internet connection, but it subsequently degrades,
interfering with video and audio transmission. In these situations, it may be possible
for the examiner to guide the patient with his or her companion, record videos of
the necessary tests, and send them for a subsequent “off-line” analysis. These guidelines
can be provided by the examiner during the live transmission, or by sending instruction
materials (such as links to web pages or prerecorded instructional videos). This asynchronous
(“store and forward”) technique is still a viable approach to teleconsultation, as
was made clear in a study[27 ] demonstrating its usefulness in the differential diagnosis of Ménière disease, and
in findings of central and peripheral deficits. Furthermore, the practice of recording
oculomotor and other physical examination findings by smartphone was even described
in the emergency department setting, where, with the use of the device, the eye movements
of patients were recorded, which were evaluated at another time by specialists.[25 ]
Limitations imposed by the inability to eliminate the suppression of the visual fixation
Removal of the suppression of the visual fixation is a very important factor during
certain parts of the neurotological assessment, as this can “unmask” certain forms
of nystagmus.[44 ]
[45 ]
[46 ]
[47 ]
[48 ]
[49 ]
[50 ]
[51 ]
[52 ] Routinely, clinicians use instruments such as Frenzel glasses and infrared Frenzel
video goggles to achieve this effect. However, other resources can be used during
the exam, such as the ophthalmoscope.[53 ] For otoneurological teleconsultations, a reasonable adaptation is for the patient
to occlude one eye manually, or, if possible, with adhesive occlusive material (such
as an eye patch), and the companion should shine a flashlight on the other (unoccluded)
eye during the perfomance of the tests guided by the examiner. While imperfect, this
is still a reasonable method to decrease visual fixation in order to bring out any
latent oculomotor abnormalities.
Otoneurology is a growing field, and its diagnostic capabilities have been enhanced
by technology, but the importance of the bedside clinical assessment should not be
overlooked, and is still highly recommended when feasible.[54 ] While the number of vestibular clinicians is growing, the availability of clinicians
of this subspecialty is still greatly exceeded by the demand for care, because vestibular
disease is extraordinarily common. While technology has been helpful, much of this
specialized equipment may be unaffordable or simply unavailable, even though the need
for care continues to grow.
Teleconsultation relies on the same clinical skills that one would use during an in-person
evaluation. The limitations imposed by the COVID-19 pandemic should spur us all to
reflect on the need to be prepared for adverse circumstances, to be nimble and adapt
the practice with new resources, as each situation may require ([Fig. 2 ]).
