This is the current release of the guideline.

This guideline updates a previous version: Spring DB, Francis IR, Casalino DD, Arellano RS, Baumgarten DA, Curry NS, Dighe M, Israel GM, Jafri SZ, Kawashima A, Leyendecker JR, Papanicolaou N, Prasad S, Ramchandani P, Remer EM, Sheth S, Fulgham P, Expert Panel on Urologic Imaging. ACR Appropriateness Criteria® recurrent lower urinary tract infections in women. [online publication]. Reston (VA): American College of Radiology (ACR); 2008. 7 p.

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

Recurrent lower urinary tract infections (UTIs)

To evaluate the appropriateness of radiologic examinations for recurrent lower urinary tract infections (UTIs) in women

Women with recurrent lower urinary tract infections (UTIs)

Utility of radiologic examinations in the investigation of recurrent lower urinary tract infections (UTIs) in women

Literature Search Procedure

The Medline literature search is based on keywords provided by the topic author. The two general classes of keywords are those related to the condition (e.g., ankle pain, fever) and those that describe the diagnostic or therapeutic intervention of interest (e.g., mammography, MRI).

The search terms and parameters are manipulated to produce the most relevant, current evidence to address the American College of Radiology Appropriateness Criteria (ACR AC) topic being reviewed or developed. Combining the clinical conditions and diagnostic modalities or therapeutic procedures narrows the search to be relevant to the topic. Exploding the term "diagnostic imaging" captures relevant results for diagnostic topics.

The following criteria/limits are used in the searches.

1. Articles that have abstracts available and are concerned with humans.
2. Restrict the search to the year prior to the last topic update or in some cases the author of the topic may specify which year range to use in the search. For new topics, the year range is restricted to the last 5 years unless the topic author provides other instructions.
3. May restrict the search to Adults only or Pediatrics only.
4. Articles consisting of only summaries or case reports are often excluded from final results.

The search strategy may be revised to improve the output as needed.

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

Strength of Evidence Key

Category 1 - The conclusions of the study are valid and strongly supported by study design, analysis and results.

Category 2 - The conclusions of the study are likely valid, but study design does not permit certainty.

Category 3 - The conclusions of the study may be valid but the evidence supporting the conclusions is inconclusive or equivocal.

Category 4 - The conclusions of the study may not be valid because the evidence may not be reliable given the study design or analysis.

The topic author drafts or revises the narrative text summarizing the evidence found in the literature. American College of Radiology (ACR) staff draft an evidence table based on the analysis of the selected literature. These tables rate the strength of the evidence for all articles included in the narrative text.

The expert panel reviews the narrative text, evidence table, and the supporting literature for each of the topic-variant combinations and assigns an appropriateness rating for each procedure listed in the table. Each individual panel member forms his/her own opinion based on his/her interpretation of the available evidence.

More information about the evidence table development process can be found in the American College of Radiology (ACR) Appropriateness Criteria® Evidence Table Development document (see the "Availability of Companion Documents" field).

Modified Delphi Technique

The appropriateness ratings for each of the procedures included in the Appropriateness Criteria topics are determined using a modified Delphi methodology. A series of surveys are conducted to elicit each panelist's expert interpretation of the evidence, based on the available data, regarding the appropriateness of an imaging or therapeutic procedure for a specific clinical scenario. American College of Radiology (ACR) staff distributes surveys to the panelists along with the evidence table and narrative. Each panelist interprets the available evidence and rates each procedure. The surveys are completed by panelists without consulting other panelists. The ratings are a scale between 1 and 9, which is further divided into three categories: 1, 2, or 3 is defined as "usually not appropriate"; 4, 5, or 6 is defined as "may be appropriate"; and 7, 8, or 9 is defined as "usually appropriate." Each panel member assigns one rating for each procedure per survey round. The surveys are collected and the results are tabulated, de-identified and redistributed after each round. A maximum of three rounds are conducted. The modified Delphi technique enables each panelist to express individual interpretations of the evidence and his or her expert opinion without excessive bias from fellow panelists in a simple, standardized and economical process.

Consensus among the panel members must be achieved to determine the final rating for each procedure. Consensus is defined as eighty percent (80%) agreement within a rating category. The final rating is determined by the median of all the ratings once consensus has been reached. Up to three rating rounds are conducted to achieve consensus.

If consensus is not reached, the panel is convened by conference call. The strengths and weaknesses of each imaging procedure that has not reached consensus are discussed and a final rating is proposed. If the panelists on the call agree, the rating is accepted as the panel's consensus. The document is circulated to all the panelists to make the final determination. If consensus cannot be reached on the call or when the document is circulated, "No consensus" appears in the rating column and the reasons for this decision are added to the comment sections.

Not applicable

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

ACR Appropriateness Criteria®

Clinical Condition: Recurrent Lower Urinary Tract Infections in Women

Variant 1: With no underlying risk factors.

Radiologic Procedure	Rating	Comments	RRL*
CT abdomen and pelvis without and with contrast	2
X-ray abdomen	2
CT abdomen and pelvis without contrast	2
CT abdomen and pelvis with contrast	2
X-ray contrast enema	2
X-ray cystography	2
MRI pelvis without and with contrast	2	MRI may be indicated if urethral diverticulum is suspected.	O
MRI pelvis without contrast	2		O
US kidneys and bladder retroperitoneal	2		O
US pelvis (bladder)	2		O
Tc-99m sulfur colloid cystography	2
X-ray voiding cystourethrography	2
X-ray intravenous urography	1	Not cost-effective in this group. Has been supplanted by CT and MR urography.
US pelvis (urethra)	1		O
Rating Scale: 1,2,3 Usually not appropriate; 4,5,6 May be appropriate; 7,8,9 Usually appropriate			*Relative Radiation Level

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

Variant 2: Patients who are nonresponders to conventional therapy, get frequent reinfections or relapses, and have known underlying risk factors.

Radiologic Procedure	Rating	Comments	RRL*
CT abdomen and pelvis without and with contrast	7
MRI pelvis without and with contrast	6	For suspected diverticulum or prolapse. Favored for patients who require repeated imaging examinations. See statement regarding contrast in text under "Anticipated Exceptions."	O
US pelvis (urethra)	5	Favored for pregnant women.	O
MRI pelvis without contrast	4		O
X-ray voiding cystourethrography	4	For reflux, bladder or urethral fistula, or prolapse.
US kidneys and bladder retroperitoneal	3	Less accurate for detection of pyelonephritis.	O
X-ray intravenous urography	3	Limited use (or alternative) in young patients if MR is unavailable or not possible.
CT abdomen and pelvis with contrast	3
US pelvis (bladder)	2	Also to evaluate for postvoid residual.	O
X-ray urethrography double balloon	2
X-ray abdomen	2
CT abdomen and pelvis without contrast	2
X-ray contrast enema	2	May be useful for vesicoenteric fistula.
X-ray cystography	2	May be useful for vesicoenteric fistula.
Tc-99m sulfur colloid cystography	2
Rating Scale: 1,2,3 Usually not appropriate; 4,5,6 May be appropriate; 7,8,9 Usually appropriate			*Relative Radiation Level

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

Summary of Literature Review

Urinary tract infections (UTI) are among the most common bacterial infections in women. Every year in the United States, about 15% of women are diagnosed with UTIs. Most occur in healthy, sexually active women with a normal urinary tract and normal renal function. These infections are usually limited to the lower urinary tract, are not recurrent, and respond to appropriate antimicrobial therapy. Lower UTIs are confined to the bladder and occasionally the urethra and result in irritative voiding symptoms such as frequency, dysuria, urgency, and hematuria in severe cases. There is usually no associated flank pain, fever, or other systemic symptoms. Complicated UTIs are those occurring in patients with underlying structural or medical problems. Uncomplicated UTI is classified as UTI without structural or functional abnormalities of the urinary tract and without relevant comorbidities.

Recurrent lower UTIs are usually defined as at least three episodes of infection within the preceding 12 months. Antibiotic prophylaxis is the most effective way to reduce recurrent UTIs. In most cases, such infections are the result of sexual habits and hygiene (e.g., women who are sexually active, especially those using diaphragms and/or spermatocides). In fact, such lower UTIs are commonly referred to as "honeymoon cystitis." A clean-catch or catheterized specimen for culture typically reveals >100,000 organisms per milliliter of urine. The typical infecting organism is Escherichia coli. The route of infection is ascending from the perianal area and vagina via the urethra and into the bladder. It is not at all uncommon for such infections to be severe enough to result in gross hematuria. Postmenopausal women are at increased risk for recurrent UTI in the presence of urinary incontinence, cystocele, or high postvoid residuals of urine.

Three-day antimicrobial regimens are effective in at least 90% of women. Women who have three or more symptomatic infections over a 12-month period may benefit from prophylaxis. In patients without underlying risk factors (see Appendix 1 of the original guideline document) and with lower UTIs as defined above that do not exceed two episodes per year on average, and that respond promptly to appropriate therapy, imaging is usually not cost-effective.

"Relapses" of recurrent lower UTIs in women must be differentiated from "reinfection," which may indicate causes such as a vesicovaginal or vesicoenteric fistula or a paravesical abscess with fistula to the bladder. Recurrent and chronic infections with the same organism are termed "relapses" or "persistent" infections. If infection develops more than 2 weeks after a symptomatic cure, or if it is caused by a second pathogen, it is termed a "reinfection." Causes of bacterial persistence include calculi, foreign bodies, urethral or bladder diverticula, infected urachal cyst, and postoperative changes such as a remaining ureteral stump that retains urine and results in stasis. In such patients with frequent relapses or reinfections, imaging is indicated to detect a treatable condition and monitor its progress.

Imaging Options

In support of the premise that imaging has little efficacy in uncomplicated lower UTIs in women, several studies evaluating women with recurrent UTIs with intravenous urography (IVU) revealed no findings that altered the medical or surgical management. In an additional study, the 6% of patients with recurrent UTIs that demonstrated "major structural urologic abnormalities requiring further therapy" all had risk factors (to be defined subsequently).

Therefore, imaging studies should be reserved for women who do not respond promptly to appropriate antimicrobial therapy, those who suffer frequent reinfections or relapses, and those with known risk factors. Other documented risk factors include: childhood UTIs, flank pain, fever >38.5° C, history of urinary calculi or urinary tract obstruction, obstructive voiding symptoms (straining to urinate, feeling of incomplete bladder emptying, etc.), infection with a urea-splitting organism, abnormal renal function studies, pelvic floor dysfunction, neurogenic bladder dysfunction, history of genitourinary surgery, asymptomatic bacteriuria, diabetes mellitus or other immunocompromised states, and analgesic abuse.

The following paragraphs discuss the various imaging examinations that may be useful in evaluating women with recurrent UTIs.

Radiography

Radiography of the abdomen has long been an important examination for detecting calculi, bladder wall calcifications, gas in the wall or lumen of the urinary bladder, and/or foreign bodies that may be the etiology of a UTI. Use of digital tomosynthesis of the abdomen results in improved detection of urinary stones in general over digital radiography, with only a slight increase in effective dose.

When calcifications are seen in the bladder wall, it is often possible to make a correct clinical diagnosis if these findings are viewed in the context of the clinical history, physical examination, appropriate laboratory studies, and further imaging of the remainder of the urinary tract. Bladder wall calcification is typically due to prior infection with schistosomiasis (uncommon in the United States, but very common in other parts of the world), tuberculosis, cytoxan cystitis, or radiation cystitis.

Intravenous Urography

Historically, IVU was the imaging study of choice to evaluate the urinary tract. However, computed tomography (CT) and magnetic resonance urography have supplanted the use of IVU in many institutions. IVU optimally includes thin-section nephrotomography, which may show renal scarring to indicate prior episodes of pyelonephritis. Although ill-defined renal margins may suggest a perirenal inflammatory process, complications of suspected pyelonephritis are best evaluated by CT. However, for evaluation of the collecting system, IVU may detect the changes caused by reflux nephropathy, papillary necrosis, and subtle urothelial neoplasms, as well as other changes associated with infections such as pyelitis cystica and leukoplakia. IVU is also useful for detecting or excluding congenital anomalies or obstruction of the urinary tract. The bladder phase of the IVU can usually identify contour abnormalities suggestive of inflammation or neoplasm. Further, the ability of the bladder to empty on voiding can be reasonably assessed. Cystoscopy is the best method to evaluate bladder wall pathology suspected on imaging studies. In patients with recurrent UTIs, investigators have found that 9 of 118 (8%) patients had abnormalities on cystoscopy. Additionally, patients with no underlying risk factors demonstrate a very high negative predictive value for cystoscopy.

The weaknesses of IVU include the lack of parenchymal detail and the inability to characterize filling defects. CT of the abdomen and pelvis without and with contrast and including high resolution imaging during the excretory phase (CT urography) has superseded IVU.

Computed Tomography

CT without and with intravenous contrast has been described as the "examination of choice" in evaluating complicated UTIs for detecting underlying structural problems or complications. CT is the modality of choice for evaluating acute bacterial nephritis. This is especially true in patients with known underlying risk factors, repeated episodes of reinfection, or persistent infection despite adequate therapy. CT can not only define the extent of disease but also identify complications such as renal and perirenal abscess which may be associated with these infections.

Although abdominal radiography is considered the most cost-effective imaging modality for detecting radio-opaque calculi associated with recurrent UTI, it may prove inadequate in some cases (e.g., poor definition due to moderate overlying bowel, radiolucent calculi). Its benefits include increased accuracy in detecting calculi (contrast resolution and lack of overlying bowel and bone), increased speed of examination, and increased abdominal detail, allowing, in some cases, an alternate diagnosis to explain patients' signs, symptoms, and laboratory findings. As a result, unenhanced CT has been used predominantly for the emergency patient with "renal colic" and/or hematuria. It has also been used to define the severity and extent of upper-tract calculi, which are sometimes associated with recurrent UTIs. Reduced-radiation protocols for CT are being developed, which result in similar detection of renal stones while reducing patient radiation exposure.

Ultrasound (US)

Some investigators have advocated the use of renal and pelvic US combined with radiographs as a replacement for IVU. They conclude that young women with recurrent UTIs should have this combination of examinations (i.e., US and radiographs) as the investigation of choice because it is cost-effective, "non-invasive, inexpensive and acceptable to the patient." US has the advantage of no ionizing radiation. US can efficiently measure postvoid residuals within the bladder and detect some bladder diverticula. However, it is less accurate in the detection of pyelonephritis when compared with other imaging modalities, including CT and magnetic resonance imaging (MRI).

Magnetic Resonance Imaging

MRI has been shown to be useful in evaluating UTI. It does not use ionizing radiation and therefore is favored in patient populations such as pregnant women, children, and patients who require repeated imaging examinations. MRI is effective at diagnosing pelvic organ prolapse. The resultant cystoceles and urinary incontinence associated with pelvic organ prolapse are significant risk factors for recurrent UTIs in postmenopausal women. MRI best assesses the structure and complexity of urethral diverticula, allowing for accurate diagnosis and improved surgical planning. Given the excellent soft-tissue contrast on MR imaging, this modality is also effective for evaluating vesicovaginal and enterovesicular fistulae.

MRI is less sensitive than CT for detecting urinary tract calculi. In a study of 149 patients, MR urography demonstrated 69% sensitivity for detecting calculi versus (vs) 100% for CT. MRI may be of greatest value in documenting active upper tract infection vs scar formation to determine whether therapy has been effective in the high-risk patient and in differentiating active infection from other complications post renal transplant.

Diverticula

Patients with suspected bladder diverticula may be imaged with cystography, US, or CT. Bladder diverticula are unusual in women and are associated with neurogenic, or postoperative bladder, or rarely are congenital. When a bladder diverticulum is at or near a ureteral orifice, voiding cystourethrography should be considered to evaluate the possibility of vesicoureteral reflux. Although used commonly in children to reduce the dose of radiation, nuclear cystography has not been used widely in adults.

A history of recurrent UTI is seen in 30% to 50% of patients with urethral diverticula. Diverticula of the urethra can be evaluated with high sensitivity and specificity by double balloon urethrography, voiding CT urethrography, and MRI. MRI best assesses the structure and complexity of urethral diverticula, allowing for accurate diagnosis and improved surgical planning. In at least one report, MRI altered the surgical management in 15% of patients. Double balloon urethrography can be technically difficult and may be uncomfortable for the patient. CT urethrography requires imaging postprocessing on a workstation.

When performing cystography and urethrography for evaluating the lower urinary tract, the use of digital radiography has been shown to decrease radiation dose by approximately 90% while maintaining diagnostic accuracy. This is particularly important in reducing the gonadal radiation dose during the examination of young women.

Enterovesical Fistulae

Enterovesical fistulae are usually caused by diverticulitis (cancer is the second most common cause). Clinical suspicion is frequently raised by the presence of UTI with pneumaturia and/or fecaluria. CT is the primary imaging modality for suspected cases of enterovesical fistulas. A group of researchers found that CT diagnosed 20 of 20 cases of enterovesical fistula. Another group found that CT revealed fistulas in 12 of 15 patients (80%). Cystoscopy was performed in 16 patients with 87.5% positive and barium enema in eight with 50% positive. The authors concluded that CT is the optimum imaging modality for diagnosis as it can also identify the underlying etiology. The multiplanar imaging capability, lack of radiation, and high soft-tissue resolution inherent to MRI also makes this modality suitable for imaging suspected fistulae, particularly when repeat imaging and radiation doses are of issue. IVU, colonoscopy US, upper gastrointestinal/small-bowel follow-through, sigmoidoscopy, and nuclear imaging have very low yields, making them even less cost-effective.

Summary

• Women with recurrent UTIs should have one or more additional risk factors to justify urologic or radiologic investigation.
• The basis for radiologic or urologic investigation of women with recurrent UTI is to detect abnormalities that could result in future morbidity. In such cases, cystoscopy may provide a cost-effective diagnosis.
• CT is a mainstream investigational modality for evaluating UTIs, especially in patients with underlying or known risk factors, episodes of reinfection or infection resistant to conventional therapy.
• Abnormalities of the bladder and the urethra have traditionally been demonstrated with cystography and urethrography, respectively, with MRI now playing a more central role in evaluation of the urethra as well as for diagnosing bladder prolapse.
• For the detection of fistulae, CT is the optimum imaging technique and may also provide an etiology.

Anticipated Exceptions

Nephrogenic systemic fibrosis (NSF) is a disorder with a scleroderma-like presentation and a spectrum of manifestations that can range from limited clinical sequelae to fatality. It appears to be related to both underlying severe renal dysfunction and the administration of gadolinium-based contrast agents. It has occurred primarily in patients on dialysis, rarely in patients with very limited glomerular filtration rate (GFR) (i.e., <30 mL/min/1.73 m²), and almost never in other patients. There is growing literature regarding NSF. Although some controversy and lack of clarity remain, there is a consensus that it is advisable to avoid all gadolinium-based contrast agents in dialysis-dependent patients unless the possible benefits clearly outweigh the risk, and to limit the type and amount in patients with estimated GFR rates <30 mL/min/1.73 m². For more information, please see the American College of Radiology (ACR) Manual on Contrast Media (see the "Availability of Companion Documents" field).

Abbreviations

• CT, computed tomography
• MRI, magnetic resonance imaging
• Tc-99m, technetium-99 metastable
• US, ultrasound

Relative Radiation Level Designations

Relative Radiation Level*	Adult Effective Dose Estimate Range	Pediatric Effective Dose Estimate Range
O	0 mSv	0 mSv
	<0.1 mSv	<0.03 mSv
	0.1-1 mSv	0.03-0.3 mSv
	1-10 mSv	0.3-3 mSv
	10-30 mSv	3-10 mSv
	30-100 mSv	10-30 mSv
*RRL assignments for some of the examinations cannot be made, because the actual patient doses in these procedures vary as a function of a number of factors (e.g., region of the body exposed to ionizing radiation, the imaging guidance that is used). The RRLs for these examinations are designated as "Varies".

Algorithms were not developed from criteria guidelines.

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

Selection of appropriate radiologic imaging procedures for evaluation of women with recurrent lower urinary tract infections (UTIs)

Gadolinium-based Contrast Agents

Nephrogenic systemic fibrosis (NSF) is a disorder with a scleroderma-like presentation and a spectrum of manifestations that can range from limited clinical sequelae to fatality. It appears to be related to both underlying severe renal dysfunction and the administration of gadolinium-based contrast agents. It has occurred primarily in patients on dialysis, rarely in patients with very limited glomerular filtration rate (GFR) (i.e., <30 mL/min/1.73 m²), and almost never in other patients. Although some controversy and lack of clarity remain, there is a consensus that it is advisable to avoid all gadolinium-based contrast agents in dialysis-dependent patients unless the possible benefits clearly outweigh the risk, and to limit the type and amount in patients with estimated GFR rates <30 mL/min/1.73 m². For more information, please see the American College of Radiology (ACR) Manual on Contrast Media (see the "Availability of Companion Documents" field).

Relative Radiation Level (RRL)

Potential adverse health effects associated with radiation exposure are an important factor to consider when selecting the appropriate imaging procedure. Because there is a wide range of radiation exposures associated with different diagnostic procedures, a relative radiation level indication has been included for each imaging examination. The RRLs are based on effective dose, which is a radiation dose quantity that is used to estimate population total radiation risk associated with an imaging procedure. Patients in the pediatric age group are at inherently higher risk from exposure, both because of organ sensitivity and longer life expectancy (relevant to the long latency that appears to accompany radiation exposure). For these reasons, the RRL dose estimate ranges for pediatric examinations are lower as compared to those specified for adults. Additional information regarding radiation dose assessment for imaging examinations can be found in the American College of Radiology (ACR) Appropriateness Criteria® Radiation Dose Assessment Introduction document (see the "Availability of Companion Documents" field).

The 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 examinations 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.

An implementation strategy was not provided.

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

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

Committee on Appropriateness Criteria, Expert Panel on Urologic Imaging

Panel Members: Elizabeth Lazarus, MD; David D. Casalino, MD; Erick M. Remer, MD; Ronald S. Arellano, MD; Jay T. Bishoff, MD; Courtney A. Coursey, MD; Manjiri Dighe, MD; Douglas F. Eggli, MD; Pat Fulgham, MD; Stanley Goldfarb, MD; Gary M. Israel, MD; John R. Leyendecker, MD; Paul Nikolaidis, MD; Nicholas Papanicolaou, MD; Srinivasa Prasad, MD; Parvati Ramchandani, MD; Sheila Sheth, MD; Raghunandan Vikram, MD

Not stated

This is the current release of the guideline.

This guideline updates a previous version: Spring DB, Francis IR, Casalino DD, Arellano RS, Baumgarten DA, Curry NS, Dighe M, Israel GM, Jafri SZ, Kawashima A, Leyendecker JR, Papanicolaou N, Prasad S, Ramchandani P, Remer EM, Sheth S, Fulgham P, Expert Panel on Urologic Imaging. ACR Appropriateness Criteria® recurrent lower urinary tract infections in women. [online publication]. Reston (VA): American College of Radiology (ACR); 2008. 7 p.

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

Electronic copies: Available in Portable Document Format (PDF) from the American College of Radiology (ACR) Web site.

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

The following are available:

• ACR Appropriateness Criteria®. Overview. 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.
• ACR Appropriateness Criteria®. Literature search process. Reston (VA): American College of Radiology; 1 p. Electronic copies: Available in Portable Document Format (PDF) from the ACR Web site.
• ACR Appropriateness Criteria®. Evidence table development. Reston (VA): American College of Radiology; 4 p. Electronic copies: Available in Portable Document Format (PDF) from the ACR Web site.
• ACR Appropriateness Criteria®. Radiation dose assessment introduction. Reston (VA): American College of Radiology; 2 p. Electronic copies: Available in Portable Document Format (PDF) from the ACR Web site.
• ACR Appropriateness Criteria® Manual on contrast media. Reston (VA): American College of Radiology; 90 p. Electronic copies: Available in PDF from the ACR Web site.

None available

This summary was completed by ECRI on May 6, 2001. The information was verified by the guideline developer as of June 29, 2001. This summary was updated by ECRI on September 7, 2004. The updated information was verified by the guideline developer on October 8, 2004. This summary was updated by ECRI on February 6, 2006. This summary was updated by ECRI Institute on July 31, 2009. This summary was updated by ECRI Institute on January 13, 2011 following the U.S. Food and Drug Administration (FDA) advisory on gadolinium-based contrast agents. This NGC summary was updated by ECRI Institute on July 28, 2011.

Instructions for downloading, use, and reproduction of the American College of Radiology (ACR) Appropriateness Criteria® may be found on the ACR Web site .