![](media/image1.png){width="5.96875in" height="0.41944444444444445in"}

Top of Form

## Complete Summary

#### GUIDELINE TITLE

Pulsatile abdominal mass.

#### BIBLIOGRAPHIC SOURCE(S)

Grollman J, Bettmann MA, Casciani T, Gomes AS, Holtzman SR, Polak JF,
Sacks D, Stanford W, Jaff M, Moneta GL, Expert Panel on Cardiovascular
Imaging. Pulsatile abdominal mass. \[online publication\]. Reston (VA):
American College of Radiology (ACR); 2005. 5 p. \[30 references\]

#### GUIDELINE STATUS

This is the current release of the guideline.

It updates a previously published version: Grollman J, Bettmann MA, Boxt
LM, Gomes AS, Henkin RE, Higgins CB, Kelley MJ, Needleman L, Pagan-Marin
H, Polak JF, Stanford W. Pulsatile abdominal mass. American College of
Radiology. ACR Appropriateness Criteria. Radiology 2000
Jun;215(Suppl):55-9. \[29 references\]

The appropriateness criteria are reviewed annually and updated by the
panels as needed, depending on introduction of new and highly
significant scientific evidence.

### \*\* REGULATORY ALERT \*\*

#### FDA WARNING/REGULATORY ALERT

**Note from the National Guideline Clearinghouse**: This guideline
references a drug(s) for which important revised regulatory and/or
warning information has been released.

-   [May 23, 2007, Gadolinium-based Contrast
    Agents](http://www.fda.gov/medwatch/safety/2007/safety07.htm#Gadolinium):
    The addition of a boxed warning and new warnings about the risk of
    nephrogenic systemic fibrosis (NSF) to the full prescribing
    information for all gadolinium-based contrast agents (GBCAs).

### COMPLETE SUMMARY CONTENT

 \*\* REGULATORY ALERT \*\*\
 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)

Pulsatile abdominal mass

#### GUIDELINE CATEGORY

Diagnosis\
Evaluation

#### CLINICAL SPECIALTY

Cardiology\
Emergency Medicine\
Family Practice\
Geriatrics\
Internal Medicine\
Radiology\
Surgery

#### INTENDED USERS

Health Plans\
Hospitals\
Managed Care Organizations\
Physicians\
Utilization Management

#### GUIDELINE OBJECTIVE(S)

To evaluate the appropriateness of initial radiologic examinations for a
pulsatile abdominal mass

#### TARGET POPULATION

Patients with pulsatile abdominal mass

#### INTERVENTIONS AND PRACTICES CONSIDERED

1.  Computed tomography angiography (CTA)

    -   Abdomen

    -   Abdomen, electron beam

2.  Ultrasound (US)

    -   Aorta

    -   Aorta, duplex

    -   Abdomen

3.  Computed tomography (CT)

    -   Abdomen, with contrast

    -   Abdomen, without contrast

    -   Virtual endoscopy

4.  Catheter aortography, aorta

5.  Magnetic resonance imaging (MRI), abdomen

6.  Magnetic resonance angiography (MRA), abdomen

7.  X-ray

    -   Abdomen

    -   Kidney, intravenous pyelogram (IVP)

8.  Invasive (INV) tests

    -   Lower extremity, runoff angiography

    -   Viscera, angiography

#### MAJOR OUTCOMES CONSIDERED

Utility of radiologic examinations in differential diagnosis

### METHODOLOGY

#### METHODS USED TO COLLECT/SELECT EVIDENCE

Searches of Electronic Databases

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

The guideline developer performed literature searches of peer-reviewed
medical journals, and the major applicable articles were identified and
collected.

#### NUMBER OF SOURCE DOCUMENTS

The total number of source documents identified as the result of the
literature search is not known.

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

Weighting According to a Rating Scheme (Scheme Not Given)

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

Not stated

#### METHODS USED TO ANALYZE THE EVIDENCE

Systematic Review with Evidence Tables

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

One or two topic leaders within a panel assume the responsibility of
developing an evidence table for each clinical condition, based on
analysis of the current literature. These tables serve as a basis for
developing a narrative specific to each clinical condition.

#### METHODS USED TO FORMULATE THE RECOMMENDATIONS

Expert Consensus (Delphi)

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

Since data available from existing scientific studies are usually
insufficient for meta-analysis, broad-based consensus techniques are
needed for reaching agreement in the formulation of the appropriateness
criteria. The American College of Radiology (ACR) Appropriateness
Criteria panels use a modified Delphi technique to arrive at consensus.
Serial surveys are conducted by distributing questionnaires to
consolidate expert opinions within each panel. These questionnaires are
distributed to the participants along with the evidence table and
narrative as developed by the topic leader(s). Questionnaires are
completed by participants in their own professional setting without
influence of the other members. Voting is conducted using a scoring
system from 1-9, indicating the least to the most appropriate imaging
examination or therapeutic procedure. The survey results are collected,
tabulated in anonymous fashion, and redistributed after each round. A
maximum of three rounds is conducted and opinions are unified to the
highest degree possible. Eighty percent agreement is considered a
consensus. This modified Delphi technique enables individual, unbiased
expression, is economical, easy to understand, and relatively simple to
conduct.

If consensus cannot be reached by the Delphi technique, the panel is
convened and group consensus techniques are utilized. The strengths and
weaknesses of each test or procedure are discussed and consensus reached
whenever possible. If \"No consensus\" appears in the rating column,
reasons for this decision are added to the comment sections.

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

Not applicable

#### COST ANALYSIS

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

#### METHOD OF GUIDELINE VALIDATION

Internal Peer Review

#### DESCRIPTION OF METHOD OF GUIDELINE VALIDATION

Criteria developed by the Expert Panels are reviewed by the American
College of Radiology (ACR) Committee on Appropriateness Criteria.

### RECOMMENDATIONS

#### MAJOR RECOMMENDATIONS

**ACR Appropriateness Criteria®**

**Clinical Condition: Pulsatile Abdominal Mass**

  ---------------------------------------------------------------------------
  **Radiologic Exam    **Appropriateness   **Comments**
  Procedure**          Rating**            
  -------------------- ------------------- ----------------------------------
  CTA, abdomen         8                   Prefer MDCTA. Accurately defines
                                           the anatomy of the aorta and its
                                           branches and the adjacent organs
                                           and tissues.

  US, aorta            8                   The definitive screening modality
                                           but only measures aortic diameter
                                           accurately.

  CT, abdomen, with    7                   Accurately defines aortic size and
  contrast                                 useful in defining extent.
                                           Relatively quick with acceptable
                                           cost.

  CATH, aorta,         7                   Accurately defines extent and
  aortography                              branch involvement but less
                                           accurate in defining diameter.
                                           Expensive and invasive.

  CT, abdomen, without 6                   If contrast injection
  contrast                                 contraindicated or for rapid and
                                           accurate screening.

  MRI, abdomen         6                   Better than CT in defining extent
                                           but more expensive and time
                                           consuming. Can diagnose an
                                           inflammatory aneurysm.

  MRA, abdomen         6                   Accurately defines the anatomy of
                                           the aorta and its branches and the
                                           adjacent organs and tissues.

  CTA, abdomen,        6                    
  electron beam                            

  X-ray, abdomen       5                   Easily performed and inexpensive,
                                           but not accurate in estimating
                                           diameter of the aorta. Lateral is
                                           more accurate than the frontal
                                           radiograph in estimating aortic
                                           diameter.

  INV, extremity,      5                   Important if there are signs or
  lower, runoff                            symptoms of peripheral vascular
  angiography                              disease.

  US, abdomen          4                   May miss small aneurysm. Useful if
                                           aorta found normal on aortic US.

  US, aorta, duplex    3                   Useful only if signs or symptoms
                                           of peripheral vascular disease are
                                           present and angiography not
                                           planned.

  INV, viscera,        3                   Rarely indicated. Risky in
  angiography                              patients with large aneurysms.

  X-ray, kidney,       3                   Only indicated if additional
  intravenous                              information needed about the
  pyelogram, (IVP)                         urinary tract. May be a supplement
                                           to contrast enhanced CT studies.

  CT virtual endoscopy 3                    

  ***Appropriateness                       
  Criteria Scale*\                         
  1 2 3 4 5 6 7 8 9\                       
  1 = Least                                
  appropriate 9 = Most                     
  appropriate**                            
  ---------------------------------------------------------------------------

Note: Abbreviations used in the table are listed at the end of the
\"Major Recommendations\" field.

Clinical palpation of a pulsating abdominal mass alerts the clinician to
the presence of a possible abdominal aortic aneurysm (AAA), a common
vascular disorder seen in older individuals. Although AAA is found more
commonly in men, women are also afflicted, especially after age 70.
However, the finding of a pulsatile abdominal mass can also be caused by
a tortuous abdominal aorta and transmitted pulsations from the aorta to
a nonvascular mass.

An AAA may be defined as a localized arterial dilatation of at least 50%
greater than the normal diameter. Arteriomegaly, a variation of the same
disease process, is a diffuse aneurysmal dilatation also greater than
50% of the expected normal diameter (some would accept the diagnosis of
arteriomegaly at a diameter somewhat less). Although any arterial
dilatation greater than the normal diameter is pathologically considered
an aneurysm, the term ectasia is commonly applied to dilatations less
than 50%.

Imaging studies are important in diagnosing the cause of a pulsatile
abdominal mass and, if an AAA is found, to determine its size, extent,
involvement of its branches and associated significant stenotic
visceral, renal, and peripheral arteries. Confirmation of the presence
of an AAA is extremely important because the mortality of ruptured AAA
is greater than 50% when the patient reaches the hospital and probably
greater than 90% if prehospital deaths are included. Currently elective
repair is recommended for aneurysms 5.5 cm or greater in diameter.
Ultrasound surveillance is recommended for aneurysms less than 5.5 cm in
diameter because survival is not improved by surgery. Imaging studies
commonly described in the literature include, in the order of their
development: abdominal radiographs, intravenous urography, catheter
aortography, US, CT, MRI, CTA, and MRA. The rapid recent technological
advances in MRI and, particularly, CT have led to changes in the
approach to the evaluation of both suspected and confirmed AAA.

**Abdominal Radiograph**

Radiographs are simple and inexpensive to obtain and, in past decades,
were the classic imaging method to determine whether a AAA was present.
The presence of calcification in the abdominal aortic wall, although
common in patients with an AAA, is not invariably present but is
necessary to positively identify a mass as vascular. Furthermore, a
tortuous, calcified aorta can mimic an AAA unless both lateral walls can
be seen. Generally, a supine anteroposterior abdominal radiograph is
obtained, but a lateral projection may be helpful and has been
recommended by some as the sole radiographic diagnostic modality.
Although radiographs may be helpful in the diagnosis of the presence of
a possible AAA, they are very unreliable for diameter measurement, an
important deficiency because the diameter is predictive of the
likelihood of rupture.

**Intravenous Urography**

Intravenous urography has the same limitations in the diagnosis of AAA,
but it can give some information about the presence of urinary tract
involvement. The additional expense does not justify its routine use for
the diagnosis of AAA. Therefore, this procedure is recommended only if
additional information about the urinary tract is needed. Further,
contrast-enhanced CT of the abdomen may be obtained if obstructive
uropathy is identified on the CT study.

**Ultrasound**

Ultrasound is the most commonly recommended screening imaging modality
because, if properly performed, CT can accurately measure the aortic
anteroposterior diameter. Also, it can be performed portably. Aortic US
specifically should be requested if evaluation is for a pulsating
abdominal mass, because general \"abdominal US\" may fail to disclose a
small AAA. Abdominal US is then requested only if aortic US reveals a
normal diameter aorta. Color flow duplex US is useful for the diagnosis
of concomitant peripheral vascular disease when there are symptoms of
claudication and the peripheral pulses, especially femoral, are
decreased or absent. If aortography is to be performed, duplex scanning
is superfluous unless concomitant renal insufficiency limits the
contrast medium load. Aortic US is limited in its ability to delineate
the craniad and caudad extent of the AAA as well as its involvement of
the visceral, renal, and iliac arteries. Transesophageal
echocardiography may define the thoracic extension of an AAA but is not
recommended as a routine diagnostic modality.

**Nuclear Medicine**

Although blood pool radionuclide imaging can visualize AAAs, there is no
real role for this technique as a routine method in the evaluation of
pulsatile abdominal masses. Renal function evaluations such as with the
Captopril challenge renal scan may have rare indications if there is
severe, difficult to control systemic hypertension. However, these
studies have no place in the routine evaluation of a pulsatile abdominal
mass.

**Computed Tomography**

CT has emerged as an accepted diagnostic imaging modality for an AAA. In
addition to accurate diameter measurement, it can delineate its extent,
justifying the significant expense above that of US. Many papers have
proposed CT as the initial diagnostic modality, suggesting that in the
absence of clinical findings of severe systemic hypertension,
claudication, or decreased peripheral pulses, no further preoperative
imaging would be necessary. Helical (spiral) CT can be performed rapidly
and can be substituted for both radiographs and US. Intravenous
iodinated contrast injection is necessary to obtain the full benefit of
this modality, although noncontrast CT will accurately measure the
diameter and delineate its extent. Helical CT with contrast (CTA) is a
technological advance that better defines the anatomic pathology and has
significantly decreased the need for angiography. Three-dimensional
reconstructions using maximum intensity projections, curved planar
reformations, and shaded surface displays are yielding superb diagnostic
images of the abdominal aorta. Multidetector or multislice CT (MDCT)
scanners, with 4 to 64 detector rows are faster and produce even better
anatomical definition of the aorta and adjacent organs and tissues and,
with new techniques, allow concomitant evaluation of renal, pelvic, and
peripheral vasculature. Electron beam CT (EBCT) angiography has been
successfully used to image the abdominal aorta, but EBCT scanners are
not widely available. Virtual CT endoscopy of the aorta and its branches
is an emerging technique that awaits validation and requires special
software.

**Magnetic Resonance Imaging**

MRI and especially MRA define the anatomic extent of AAAs better than
CT. The absence of iodinated contrast and ionizing radiation is a
further advantage of this modality. Also, this modality is less costly
than conventional angiography.

MRA specifically can image the visceral, renal, and iliac arteries. With
rapid improvement in MRA technology, including reconstruction
techniques, the ability to completely image an AAA and show its
relationship to and involvement of its immediate aortic branches is
improving. Gadolinium-enhanced 3-dimensional MRA is proving to be
superior to angiography in the diagnosis and delineation of AAA. Newer
blood pool agents may add further information and increase convenience
and speed.

**Catheter Angiography**

The routine use of catheter angiography (CA) in the imaging of pulsatile
abdominal masses and even AAAs confirmed by other modalities, previously
controversial, is now rarely necessary. CA does not accurately measure
the diameter of an AAA and rarely may even misdiagnose its absence. It
is no longer the \"gold standard\" in defining the pathologic anatomy of
an AAA and its branch and peripheral arteries. The use of CA is now
limited to institutions without adequate MR or CT technology. Selective
visceral, renal, spinal, and coronary arteriography are believed to be
indicated only in very specific clinical situations. Much of this
information can now be obtained less invasively and probably more
accurately with CTA and perhaps MRA.

**Summary**

The consensus of the literature supports aortic US as the initial
imaging modality of choice when a pulsatile abdominal mass is present.
If an AAA that may need surgical or endovascular intervention is
confirmed by US or screening helical CT, the decision between contrast
helical CT/CTA, MDCT, MRI/MRA, or conventional CA depends on the
availability of the more sophisticated imaging modalities. Helical CTA
and contrast-enhanced MRA clearly are satisfactory replacements for CA
except when there are specific unanswered questions about coexistent
peripheral vascular, renal, or visceral arterial obstructive disease or
involvement by the aneurysm. They now may be performed so rapidly,
safely, and accurately that CTA and MRA may now be considered as the
initial test in patients with high clinical suspicion.

**Anticipated Exceptions**

In emergent situations where rupture has already occurred, all the
imaging modalities may be bypassed, because the patient will need
immediate operation for survival. In urgent situations, where clinical
diagnosis is fairly certain and rupture is impending, CTA or MRA may be
the initial and only examination requested, bypassing US.

**Abbreviations**

-   CATH, catheter

-   CT, computed tomography

-   CTA, computed tomography angiography

-   INV, invasive

-   IVP, intravenous pyelogram

-   MDCTA, multidetector computed tomography angiography

-   MRA, magnetic resonance angiography

-   MRI, magnetic resonance imaging

-   US, ultrasound

#### CLINICAL ALGORITHM(S)

Algorithms were not developed from criteria guidelines.

### EVIDENCE SUPPORTING THE RECOMMENDATIONS

#### TYPE OF EVIDENCE SUPPORTING THE RECOMMENDATIONS

The recommendations are based on analysis of the current literature and
expert panel consensus.

### BENEFITS/HARMS OF IMPLEMENTING THE GUIDELINE RECOMMENDATIONS

#### POTENTIAL BENEFITS

Selection of appropriate radiologic imaging procedures for evaluation of
patients with pulsatile abdominal mass

#### POTENTIAL HARMS

Although abdominal radiographs may be helpful in the diagnosis of the
presence of a possible abdominal aortic aneurysm (AAA), they are very
unreliable for diameter measurement, an important deficiency because the
diameter is predictive of the likelihood of rupture.

### QUALIFYING STATEMENTS

#### QUALIFYING STATEMENTS

An American College of Radiology (ACR) Committee on Appropriateness
Criteria and its expert panels have developed criteria for determining
appropriate imaging examinations for diagnosis and treatment of
specified medical condition(s). These criteria are intended to guide
radiologists, radiation oncologists, and referring physicians in making
decisions regarding radiologic imaging and treatment. Generally, the
complexity and severity of a patient\'s clinical condition should
dictate the selection of appropriate imaging procedures or treatments.
Only those exams generally used for evaluation of the patient\'s
condition are ranked. Other imaging studies necessary to evaluate other
co-existent diseases or other medical consequences of this condition are
not considered in this document. The availability of equipment or
personnel may influence the selection of appropriate imaging procedures
or treatments. Imaging techniques classified as investigational by the
U.S. Food and Drug Administration (FDA) have not been considered in
developing these criteria; however, study of new equipment and
applications should be encouraged. The ultimate decision regarding the
appropriateness of any specific radiologic examination or treatment must
be made by the referring physician and radiologist in light of all the
circumstances presented in an individual examination.

### IMPLEMENTATION OF THE GUIDELINE

#### DESCRIPTION OF IMPLEMENTATION STRATEGY

An implementation strategy was not provided.

#### IMPLEMENTATION TOOLS

Personal Digital Assistant (PDA) Downloads

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

#### IOM DOMAIN

Effectiveness

### IDENTIFYING INFORMATION AND AVAILABILITY

#### BIBLIOGRAPHIC SOURCE(S)

Grollman J, Bettmann MA, Casciani T, Gomes AS, Holtzman SR, Polak JF,
Sacks D, Stanford W, Jaff M, Moneta GL, Expert Panel on Cardiovascular
Imaging. Pulsatile abdominal mass. \[online publication\]. Reston (VA):
American College of Radiology (ACR); 2005. 5 p. \[30 references\]

#### ADAPTATION

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

#### DATE RELEASED

1995 (revised 2005)

#### GUIDELINE DEVELOPER(S)

American College of Radiology - Medical Specialty Society

#### SOURCE(S) OF FUNDING

The American College of Radiology (ACR) provided the funding and the
resources for these ACR Appropriateness Criteria®.

#### GUIDELINE COMMITTEE

Committee on Appropriateness Criteria, Expert Panel on Cardiovascular
Imaging

#### COMPOSITION OF GROUP THAT AUTHORED THE GUIDELINE

*Panel Members*: Julius Grollman, MD (*Principal Author*); Michael A.
Bettmann, MD (*Panel Chair*); Thomas Casciani, MD; Antoinette S. Gomes,
MD; Stephen R. Holtzman, MD; Joseph F. Polak, MD, MPH; David Sacks, MD;
William Stanford, MD; Michael Jaff, MD; Gregory L. Moneta, MD

#### FINANCIAL DISCLOSURES/CONFLICTS OF INTEREST

Not stated

#### GUIDELINE STATUS

This is the current release of the guideline.

It updates a previously published version: Grollman J, Bettmann MA, Boxt
LM, Gomes AS, Henkin RE, Higgins CB, Kelley MJ, Needleman L, Pagan-Marin
H, Polak JF, Stanford W. Pulsatile abdominal mass. American College of
Radiology. ACR Appropriateness Criteria. Radiology 2000
Jun;215(Suppl):55-9. \[29 references\]

The appropriateness criteria are reviewed annually and updated by the
panels as needed, depending on introduction of new and highly
significant scientific evidence.

#### GUIDELINE AVAILABILITY

Electronic copies: Available Portable Document Format (PDF) from the
[American College of Radiology (ACR) Web
site](http://www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria/pdf/Vascular/PulsatileAbdominalMassDoc13.aspx).

ACR Appropriateness Criteria® *Anytime*, *Anywhere*™ (PDA application).
Available from the [ACR Web
site](http://www.acr.org/SecondaryMainMenuCategories/ACRStore/FeaturedCategories/QualityandSafety/ac_pda.aspx).

Print copies: Available from the American College of Radiology, 1891
Preston White Drive, Reston, VA 20191. Telephone: (703) 648-8900.

#### AVAILABILITY OF COMPANION DOCUMENTS

The following is available:

-   ACR Appropriateness Criteria®. Background and development. Reston
    (VA): American College of Radiology; 2 p. Electronic copies:
    Available in Portable Document Format (PDF) from the [American
    College of Radiology (ACR) Web
    site](http://www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria/pdf/background_dev.aspx).

#### PATIENT RESOURCES

None available

#### NGC STATUS

This summary was completed by ECRI on February 20, 2001. The information
was verified by the guideline developer on March 14, 2001. This summary
was updated by ECRI on March 6, 2006. This summary was updated by ECRI
Institute on May 17, 2007 following the U.S. Food and Drug
Administration (FDA) advisory on Gadolinium-based contrast agents. This
summary was updated by ECRI Institute on June 20, 2007 following the
U.S. Food and Drug Administration (FDA) advisory on gadolinium-based
contrast agents.

#### COPYRIGHT STATEMENT

Instructions for downloading, use, and reproduction of the American
College of Radiology (ACR) Appropriateness Criteria® may be found on the
[ACR Web
site.](http://www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria/ACRAppropriatenessCriteriaTermsandConditionsDoc1.aspx)

### DISCLAIMER

#### NGC DISCLAIMER

The National Guideline Clearinghouse™ (NGC) does not develop, produce,
approve, or endorse the guidelines represented on this site.

All guidelines summarized by NGC and hosted on our site are produced
under the auspices of medical specialty societies, relevant professional
associations, public or private organizations, other government
agencies, health care organizations or plans, and similar entities.

Guidelines represented on the NGC Web site are submitted by guideline
developers, and are screened solely to determine that they meet the NGC
Inclusion Criteria which may be found at
<http://www.guideline.gov/about/inclusion.aspx> .

NGC, AHRQ, and its contractor ECRI Institute make no warranties
concerning the content or clinical efficacy or effectiveness of the
clinical practice guidelines and related materials represented on this
site. Moreover, the views and opinions of developers or authors of
guidelines represented on this site do not necessarily state or reflect
those of NGC, AHRQ, or its contractor ECRI Institute, and inclusion or
hosting of guidelines in NGC may not be used for advertising or
commercial endorsement purposes.

Readers with questions regarding guideline content are directed to
contact the guideline developer.

Bottom of Form

© 1998-2008 National Guideline Clearinghouse

Date Modified: 11/3/2008