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## Complete Summary

#### GUIDELINE TITLE

Assessment: transcranial Doppler ultrasonography: report of the
Therapeutics and Technology Assessment Subcommittee of the American
Academy of Neurology.

#### BIBLIOGRAPHIC SOURCE(S)

Sloan MA, Alexandrov AV, Tegeler CH, Spencer MP, Caplan LR, Feldmann E,
Wechsler LR, Newell DW, Gomez CR, Babikian VL, Lefkowitz D, Goldman RS,
Armon C, Hsu CY, Goodin DS. Assessment: transcranial Doppler
ultrasonography: report of the Therapeutics and Technology Assessment
Subcommittee of the American Academy of Neurology. Neurology 2004 May
11;62(9):1468-81. \[149 references\]
[PubMed](http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15136667)

#### GUIDELINE STATUS

This is the current release of the guideline.

### COMPLETE SUMMARY CONTENT

 SCOPE\
 METHODOLOGY - including Rating Scheme and Cost Analysis\
 RECOMMENDATIONS\
 EVIDENCE SUPPORTING THE RECOMMENDATIONS\
 BENEFITS/HARMS OF IMPLEMENTING THE GUIDELINE RECOMMENDATIONS\
 QUALIFYING STATEMENTS\
 IMPLEMENTATION OF THE GUIDELINE\
 INSTITUTE OF MEDICINE (IOM) NATIONAL HEALTHCARE QUALITY REPORT
CATEGORIES\
 IDENTIFYING INFORMATION AND AVAILABILITY\
 DISCLAIMER

### SCOPE

#### DISEASE/CONDITION(S)

-   Stroke in children with sickle cell disease

-   Right-to-left cardiac shunts

-   Intracranial steno-occlusive disease

-   Occlusion of the middle cerebral artery, intracranial artery,
    vertebral artery, basilar artery (acute cerebral infarction)

-   Extracranial internal carotid artery (ICA) stenosis

-   Cerebral microembolization

-   Reocclusion or recanalization during central thrombolysis

-   Vasospasm after spontaneous subarachnoid hemorrhage

-   Vasospasm after traumatic subarachnoid hemorrhage

-   Cerebral circulatory arrest and brain death

-   Intracerebral hemorrhage

-   Stroke following coronary artery bypass surgery

-   Stroke following carotid endarterectomy

#### GUIDELINE CATEGORY

Diagnosis\
Technology Assessment

#### CLINICAL SPECIALTY

Neurology\
Radiology

#### INTENDED USERS

Physicians

#### GUIDELINE OBJECTIVE(S)

-   To determine if transcranial Doppler ultrasonography (TCD) provides
    useful information in specific clinical settings

-   To determine if using this information improves clinical decision
    making, as reflected by improved patient outcomes

-   To determine if TCD is preferable to other diagnostic tests in these
    clinical situations

#### TARGET POPULATION

Patients (adults and children) with cerebrovascular disease or stroke
and those who are in various clinical settings that place them at risk
of cerebrovascular disease or stroke

#### INTERVENTIONS AND PRACTICES CONSIDERED

**[Diagnosis]{.underline}**

1.  Transcranial Doppler ultrasonography (TCD)

2.  Transcranial color-coded sonography (TCCS)

**Procedures using TCD and/or TCCS**

1.  Vasomotor reactivity testing

2.  Detection of cerebral microembolic signals

3.  Carotid endarterectomy (CEA)

4.  Coronary artery bypass graft (CABG) surgery

5.  Cerebral thrombolysis monitoring

**Reference Standards**

1.  Conventional and digital subtraction angiography (DSA)

2.  Magnetic resonance angiography (MRA)

3.  Computed tomographic angiography (CTA)

4.  Contrast-enhanced transesophageal echocardiography (TEE)

#### MAJOR OUTCOMES CONSIDERED

-   Sensitivity and specificity of diagnostic tests

-   Positive predictive and negative predictive values

### METHODOLOGY

#### METHODS USED TO COLLECT/SELECT EVIDENCE

Hand-searches of Published Literature (Primary Sources)\
Hand-searches of Published Literature (Secondary Sources)\
Searches of Electronic Databases

#### DESCRIPTION OF METHODS USED TO COLLECT/SELECT THE EVIDENCE

The subcommittee reviewed summary statements and other articles, based
on selection of relevant publications cited in these new articles and
additional Medline search through June 2003.

#### NUMBER OF SOURCE DOCUMENTS

Not stated

#### METHODS USED TO ASSESS THE QUALITY AND STRENGTH OF THE EVIDENCE

Weighting According to a Rating Scheme (Scheme Given)

#### RATING SCHEME FOR THE STRENGTH OF THE EVIDENCE

**Rating of Diagnostic Article**

**Class I**: Evidence provided by prospective study in broad spectrum of
persons with suspected condition, using a \"gold standard\" to define
cases, where test is applied in blinded evaluation, and enabling
assessment of appropriate tests of diagnostic accuracy.

**Class II**: Evidence provided by prospective study in narrow spectrum
of persons with suspected condition or well-designed retrospective study
of broad spectrum of persons with suspected condition (by \"gold
standard\") compared with broad spectrum of controls where test is
applied in blinded evaluation and enabling assessment of appropriate
tests of diagnostic accuracy.

**Class III**: Evidence provided by retrospective study where either
persons with established condition or controls are of narrow spectrum
and where test is applied in blinded evaluation.

**Class IV**: Any design where test is not applied in blinded fashion or
evidence provided by expert opinion or descriptive case series.

**Rating of Prognostic Article**

**Class I**: Evidence provided by prospective study in broad spectrum of
persons who may be at risk of outcome (target disease, work status).
Study measures predictive ability using independent gold standard to
define cases. Predictor is measured in evaluation masked to clinical
presentation. Outcome is measured in evaluation masked to presence of
predictor.

**Class II**: Evidence provided by prospective study of narrow spectrum
of persons who may be at risk for having the condition, retrospective
study of broad spectrum of persons with condition compared with broad
spectrum of controls. Study measures prognostic accuracy of risk factor
using acceptable independent gold standard to define cases. Risk factor
is measured in evaluation masked to the outcome.

**Class III**: Evidence provided by retrospective study where persons
with condition or controls are of narrow spectrum. Study measures
predictive ability using independent gold standard to define cases. Risk
factor measured in evaluation masked to outcome.

**Class IV**: Any design where predictor is not applied in masked
evaluation or evidence by expert opinion, case series.

#### METHODS USED TO ANALYZE THE EVIDENCE

Systematic Review

#### DESCRIPTION OF THE METHODS USED TO ANALYZE THE EVIDENCE

Summary statements and other selected articles were reviewed using the
American Academy of Neurology rating system (refer to the \"Rating
Scheme for the Strength of the Evidence\" and \"Rating Scheme for the
Strength of the Recommendations\" fields in this summary). When data
were inconclusive, a U rating was given. Articles reviewed and cited
within the original guideline document reflect a mixture of diagnostic,
therapeutic, or prognostic information used as the reference standard in
individual studies. Sensitivity and specificity reflect the ability of a
diagnostic test to detect disease. For the purposes of this review,
ratings of sensitivity and specificity were operationally defined as
excellent ([\>]{.underline}90%), good (80 to 89%), fair (60 to 79%), and
poor (\<60%). The subcommittee reviewed the sensitivity and specificity
of transcranial Doppler ultrasonography (TCD) (please refer to table 2
of the original guideline document) and transcranial color-coded
sonography (TCCS) (please refer to table 3 of the original guideline
document) for various disease states.

The clinical utility of a diagnostic test may be operationally defined
as the value of the test result to the clinician caring for the
individual patient. In this sense, value to the clinician refers to the
ability of a diagnostic test to detect the disease process of interest,
influence patient care, or provide prognostic information when compared
with an appropriate reference standard or in a well-designed clinical
trial. The subcommittee summarized the clinical utility (see table
below) of TCD/TCCS and focused on the clinical indications for which
conclusions can be drawn.

**Table: Definitions for Clinical Utility**

1.  Able to provide information and clinical utility established

2.  Able to provide information and clinical utility, compared with
    other diagnostic tools, remains to be determined

3.  Able to provide information, but clinical utility remains to be
    determined

4.  Able to provide information, but other diagnostic tests are
    preferable in most cases

#### METHODS USED TO FORMULATE THE RECOMMENDATIONS

Other

#### DESCRIPTION OF METHODS USED TO FORMULATE THE RECOMMENDATIONS

When formulating the recommendations the guideline developers considered
the *magnitude* of the effect (benefit or harm of therapy, accuracy of
tests, yield of studies) and the relative *value* of various outcomes.
Under most circumstances, there is a direct link between the level of
evidence used to formulate conclusions and the strength of the
recommendation. This linkage is illustrated in Appendix 9 of the 2004
AAN Guideline Process Manual (see Companion Documents field). Thus, an
\"established as\" (two class I) conclusion supports a \"should be
done\" (level A) recommendation; a \"probably effective\" (two class II)
conclusion supports a \"should be considered\" (level B) recommendation;
a \"possibly effective\" (two class III) conclusion supports a \"may be
considered\" recommendation. In those circumstances where the evidence
indicates that the intervention is not effective or useful, wording was
modified. For example, if multiple adequately powered class I studies
demonstrated that an intervention is not effective, the recommendation
read, \"should not be done.\"

There are important exceptions to the rule of having a direct linkage
between the level of evidence and the strength of recommendations. Some
situations where it may be necessary to break this linkage are listed
below:

-   A statistically significant but marginally important benefit of the
    intervention is observed

-   The intervention is exorbitantly costly

-   Superior and established alternative interventions are available

-   There are competing outcomes (both beneficial and harmful) that
    cannot be reconciled

Under such circumstances the guideline developers may have downgraded
the level of the recommendation.

Edlund W, Gronseth G, So Y, Franklin G. Clinical practice guideline
process manual. St. Paul (MN): American Academy of Neurology (AAN);
2004. 49 p.

#### RATING SCHEME FOR THE STRENGTH OF THE RECOMMENDATIONS

**Rating of Recommendations**

**A** = established as useful/predictive or not useful/predictive for
the given condition in the specified population.

**B** = probably useful/predictive or not useful/predictive for the
given condition in the specified populations.

**C** = possibly useful/predictive or not useful/predictive for the
given condition in the specified population.

**D** = data inadequate or conflicting. Given current knowledge,
test/predictor unproven.

**U** = data inconclusive.

**Translation of Evidence to Recommendations**

**Level A** rating requires [\>]{.underline}1 convincing Class I or
[\>]{.underline}2 consistent, convincing Class II studies.

**Level B** rating requires [\>]{.underline}1 convincing Class II or
[\>]{.underline}3 consistent Class III studies.

**Level C** rating requires [\>]{.underline}2 convincing and consistent
Class III studies.

#### COST ANALYSIS

A formal cost analysis was not performed and published cost analyses
were not reviewed.

#### METHOD OF GUIDELINE VALIDATION

External Peer Review\
Internal Peer Review

#### DESCRIPTION OF METHOD OF GUIDELINE VALIDATION

Guidelines were approved by the Therapeutics and Technology Assessment
Subcommittee on August 8, 2003, the Practice Committee on November 8,
2003, and the Board of Directors on January 18, 2004.

### RECOMMENDATIONS

#### MAJOR RECOMMENDATIONS

Definitions of the strength of the recommendations (A, B, C, U) and
classification of the evidence (Class I through Class IV) are provided
at the end of the \"Major Recommendations\" field.

1.  Settings in which transcranial Doppler ultrasonography (TCD) is able
    to provide information and in which its clinical utility is
    established.

    a.  Screening of children aged 2 to 16 years with sickle cell
        disease for assessing stroke risk (**Type A, Class I**),
        although the optimal frequency of testing is unknown (**Type
        U**).

    b.  Detection and monitoring of angiographic vasospasm (VSP)
        spontaneous subarachnoid hemorrhage (sSaH) (**Type A, Class
        I-II**). More data are needed to show if its use affects
        clinical outcomes (**Type U**).

2.  Settings in which TCD is able to provide information, but in which
    its clinical utility, compared with other diagnostic tools, remains
    to be determined.

    a.  Intracranial steno-occlusive disease. TCD is probably useful
        (**Type B, Class II to III**) for the evaluation of occlusive
        lesions of intracranial arteries in the basal cisterns
        (especially the internal carotid artery \[ICA\] siphon and
        middle cerebral artery \[MCA\]). The relative value of TCD
        compared with magnetic resonance angiography (MRA) or computed
        tomography angiography (CTA) remains to be determined (**Type
        U**). Data are insufficient to recommend replacement of
        conventional angiography with TCD (**Type U**).

    b.  Cerebral circulatory arrest (adjunctive test in the
        determination of brain death). If needed, TCD can be used as a
        confirmatory test, in support of a clinical diagnosis of brain
        death (**Type A, Class II**).

3.  Settings in which TCD is able to provide information, but in which
    its clinical utility remains to be determined.

    a.  Cerebral thrombolysis. TCD is probably useful for monitoring
        thrombolysis of acute MCA occlusions (**Type B, Class II to
        III**). More data are needed to assess the frequency of
        monitoring for clot dissolution and enhanced recanalization and
        to influence therapy (**Type U**).

    b.  Cerebral microembolism detection. TCD monitoring is probably
        useful for the detection of cerebral microembolic signals in a
        variety of cardiovascular/cerebrovascular disorders/procedures
        (**Type B, Class II to IV**). Data do not support the use of
        this TCD technique for diagnosis or monitoring response to
        antithrombotic therapy in ischemic cerebrovascular disease
        (**Type U**).

    c.  Carotid endarterectomy (CEA). TCD monitoring is probably useful
        to detect hemodynamic and embolic events that may result in
        perioperative stroke during and after CEA in settings where
        monitoring is felt to be necessary (**Type B, Class II to
        III**).

    d.  Coronary artery bypass graft (CABG) surgery. TCD monitoring is
        probably useful (**Type B, Class II to III**) during CABG for
        detection of cerebral microemboli. TCD is possibly useful to
        document changes in flow velocities and carbon dioxide (CO~2~)
        reactivity during CABG surgery (**Type C, Class III**). Data are
        insufficient regarding the clinical impact of this information
        (**Type U**).

    e.  Vasomotor reactivity (VMR) testing. TCD is probably useful
        (**Type B, Class II to III**) for the detection of impaired
        cerebral hemodynamics in patients with severe (\>70%)
        asymptomatic extracranial ICA stenosis, symptomatic or
        asymptomatic extracranial ICA occlusion, and cerebral
        small-artery disease. Whether these techniques should be used to
        influence therapy and improve patient outcomes remains to be
        determined (**Type U**).

    f.  VSP after traumatic subarachnoid hemorrhage (tSAH). TCD is
        probably useful for the detection of VSP following tSAH (**Type
        B, Class III**), but data are needed to show its accuracy and
        clinical impact in this setting (**Type U**).

    g.  Transcranial color-coded sonography (TCCS). TCCS is possibly
        useful (**Type C, Class III**) for the evaluation and monitoring
        of space-occupying ischemic middle cerebral artery (MCA)
        infarctions. More data are needed to show if it has value vs.
        computed tomography (CT) and magnetic resonance imaging (MRI)
        scanning and if its use affects clinical outcomes (**Type U**).

4.  Settings in which TCD is able to provide information, but in which
    other diagnostic tests are typically preferable.

    a.  Right-to-left cardiac shunts. Whereas TCD is useful for
        detection of right-to-left cardiac and extracardiac shunts
        (**Type A, Class II**), transesophageal echocardiography (TEE)
        is superior, as it can provide direct information regarding the
        anatomic site and nature of the shunt.

    b.  Extracranial ICA stenosis. TCD is possibly useful for the
        evaluation of severe extracranial ICA stenosis or occlusion
        (**Type C, Class II to III**), but, in general, carotid duplex
        and magnetic resonance angiography (MRA) are the diagnostic
        tests of choice.

    c.  Contrast-enhanced TCCS. (Contrast-enhanced) TCCS may provide
        information in patients with ischemic cerebrovascular disease
        and aneurismal subarachnoid hemorrhage (aSAH) (**Type B, Class
        II to IV**). Its clinical utility vs. CT scanning, conventional
        angiography, or nonimaging TCD is unclear (**Type U**).

**[Definitions]{.underline}**:

**Rating of Recommendations**

**A** = established as useful/predictive or not useful/predictive for
the given condition in the specified population.

**B** = probably useful/predictive or not useful/predictive for the
given condition in the specified populations.

**C** = possibly useful/predictive or not useful/predictive for the
given condition in the specified population.

**D** = data inadequate or conflicting. Given current knowledge,
test/predictor unproven.

**U** = data inconclusive.

**Translation of Evidence to Recommendations**

**Level A** rating requires [\>]{.underline}1 convincing Class I or
[\>]{.underline}2 consistent, convincing Class II studies.

**Level B** rating requires [\>]{.underline}1 convincing Class II or
[\>]{.underline}3 consistent Class III studies.

**Level C** rating requires [\>]{.underline}2 convincing and consistent
Class III studies.

**Rating of Diagnostic Article**

**Class I**: Evidence provided by prospective study in broad spectrum of
persons with suspected condition, using a \"gold standard\" to define
cases, where test is applied in blinded evaluation, and enabling
assessment of appropriate tests of diagnostic accuracy.

**Class II**: Evidence provided by prospective study in narrow spectrum
of persons with suspected condition or well-designed retrospective study
of broad spectrum of persons with suspected condition (by \"gold
standard\") compared with broad spectrum of controls where test is
applied in blinded evaluation and enabling assessment of appropriate
tests of diagnostic accuracy.

**Class III**: Evidence provided by retrospective study where either
persons with established condition or controls are of narrow spectrum
and where test is applied in blinded evaluation.

**Class IV**: Any design where test is not applied in blinded fashion or
evidence provided by expert opinion or descriptive case series.

**Rating of Prognostic Article**

**Class I**: Evidence provided by prospective study in broad spectrum of
persons who may be at risk of outcome (target disease, work status).
Study measures predictive ability using independent gold standard to
define cases. Predictor is measured in evaluation masked to clinical
presentation. Outcome is measured in evaluation masked to presence of
predictor.

**Class II**: Evidence provided by prospective study of narrow spectrum
of persons who may be at risk for having the condition, retrospective
study of broad spectrum of persons with condition compared with broad
spectrum of controls. Study measures prognostic accuracy of risk factor
using acceptable independent gold standard to define cases. Risk factor
is measured in evaluation masked to the outcome.

**Class III**: Evidence provided by retrospective study where persons
with condition or controls are of narrow spectrum. Study measures
predictive ability using independent gold standard to define cases. Risk
factor measured in evaluation masked to outcome.

**Class IV**: Any design where predictor is not applied in masked
evaluation or evidence by expert opinion, case series.

#### CLINICAL ALGORITHM(S)

None provided

### EVIDENCE SUPPORTING THE RECOMMENDATIONS

#### TYPE OF EVIDENCE SUPPORTING THE RECOMMENDATIONS

The type of supporting evidence is identified and graded for each
recommendation (see \"Major Recommendations\").

### BENEFITS/HARMS OF IMPLEMENTING THE GUIDELINE RECOMMENDATIONS

#### POTENTIAL BENEFITS

The chief advantages of TCD are as follows: It can be performed at the
bedside and repeated as needed or applied for continuous monitoring; it
is frequently less expensive than other techniques; and dye contrast
agents are not used.

#### POTENTIAL HARMS

Not stated

### QUALIFYING STATEMENTS

#### QUALIFYING STATEMENTS

This statement is provided as an educational service of the American
Academy of Neurology (AAN). It is based on an assessment of current
scientific and clinical information. It is not intended to include all
possible proper methods of care for a particular neurology problem or
all legitimate criteria for choosing to use a specific procedure.
Neither is it intended to exclude any reasonable alternative
methodologies. The AAN recognizes that specific care decisions are the
prerogative of the patient and the physician caring for the patient,
based on all of the circumstances involved.

### IMPLEMENTATION OF THE GUIDELINE

#### DESCRIPTION OF IMPLEMENTATION STRATEGY

An implementation strategy was not provided.

#### IMPLEMENTATION TOOLS

Quick Reference Guides/Physician Guides\
Slide Presentation

For information about
[availability](#identifying-information-and-availability), see the
\"Availability of Companion Documents\" and \"Patient Resources\" fields
below.

### INSTITUTE OF MEDICINE (IOM) NATIONAL HEALTHCARE QUALITY REPORT CATEGORIES

#### IOM CARE NEED

Getting Better\
Living with Illness

#### IOM DOMAIN

Effectiveness

### IDENTIFYING INFORMATION AND AVAILABILITY

#### BIBLIOGRAPHIC SOURCE(S)

Sloan MA, Alexandrov AV, Tegeler CH, Spencer MP, Caplan LR, Feldmann E,
Wechsler LR, Newell DW, Gomez CR, Babikian VL, Lefkowitz D, Goldman RS,
Armon C, Hsu CY, Goodin DS. Assessment: transcranial Doppler
ultrasonography: report of the Therapeutics and Technology Assessment
Subcommittee of the American Academy of Neurology. Neurology 2004 May
11;62(9):1468-81. \[149 references\]
[PubMed](http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15136667)

#### ADAPTATION

Not applicable: The guideline was not adapted from another source.

#### DATE RELEASED

2004 May 11

#### GUIDELINE DEVELOPER(S)

American Academy of Neurology - Medical Specialty Society

#### SOURCE(S) OF FUNDING

American Academy of Neurology (AAN)

#### GUIDELINE COMMITTEE

Therapeutics and Technology Assessment Subcommittee of the American
Academy of Neurology

#### COMPOSITION OF GROUP THAT AUTHORED THE GUIDELINE

*American Academy of Neurology (AAN) Therapeutics and Technology
Assessment Subcommittee Members*: Douglas S. Goodin, MD (*chair*); Yuen
T. So, MD, PhD (*vice-chair*); Carmel Armon, MD, MHS; Richard M.
Dubinsky, MD; Mark Hallett, MD; David Hammond, MD; Chung Y. Hsu, MD,
PhD; Andres M. Kanner, MD; David Lefkowitz, MD; Janis Miyasaki, MD;
Michael A. Sloan, MD, MS; James C. Stevens, MD

#### FINANCIAL DISCLOSURES/CONFLICTS OF INTEREST

Not stated

#### GUIDELINE STATUS

This is the current release of the guideline.

#### GUIDELINE AVAILABILITY

Electronic copies: A list of American Academy of Neurology (AAN)
guidelines, along with a link to a Portable Document Format (PDF) file
for this guideline, is available at the [AAN Web
site](http://aan.com/go/practice/guidelines).

Print copies: Available from the AAN Member Services Center, (800)
879-1960, or from AAN, 1080 Montreal Avenue, St. Paul, MN 55116.

#### AVAILABILITY OF COMPANION DOCUMENTS

The following are available:

-   Assessment of transcranial Doppler ultrasonography. AAN guideline
    summary for clinicians. St. Paul (MN): American Academy of
    Neurology. 2. p. Available in Portable Document Format (PDF) from
    the [AAN Web
    site](http://www.aan.com/professionals/practice/pdfs/transcranial_summary_clinicians.pdf).

-   Slide presentation: assessment: transcranial Doppler
    ultrasonography. St. Paul (MN): American Academy of Neurology. 2004.
    Available in Power Point from the [AAN Web
    site](http://www.aan.com/professionals/practice/guidelines/pwr_pnt/tcd.ppt).

-   AAN guideline development process \[online\]. St. Paul (MN):
    American Academy of Neurology (AAN). Available from the [AAN Web
    site](http://aan.com/go/practice/guidelines/development).

-   Edlund W, Gronseth G, So Y, Franklin G. Clinical practice guideline
    process manual. St. Paul (MN): American Academy of Neurology
    (AAN); 2004. 49 p. Electronic copies available in Portable Document
    Format (PDF) from the [AAN Web
    site](http://www.aan.com/globals/axon/assets/2535.pdf).

#### PATIENT RESOURCES

None available

#### NGC STATUS

This NGC summary was completed by ECRI on August 17, 2004. The
information was verified by the guideline developer on September 9,
2004.

#### COPYRIGHT STATEMENT

This NGC summary is based on the original guideline, which is
copyrighted by the American Academy of Neurology.

### DISCLAIMER

#### NGC DISCLAIMER

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Date Modified: 11/3/2008