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## Complete Summary

#### GUIDELINE TITLE

Acute onset of scrotal pain (without trauma, without antecedent mass).

#### BIBLIOGRAPHIC SOURCE(S)

Remer EM, Francis IR, Baumgarten DA, Bluth EI, Bush WH Jr, Casalino DD,
Curry NS, Israel GMN, Jafri SZ, Kawashima A, Papanicolaou N, Sandler CM,
Spring DB, Fulgham P, Expert Panel on Urologic imaging. Acute onset of
scrotal pain-without trauma, without antecedent mass. \[online
publication\]. Reston (VA): American College of Radiology (ACR); 2007. 5
p.

#### GUIDELINE STATUS

This is the current release of the guideline.

It updates a previous published version: Older RA, Choyke PL, Bluth EI,
Bush WH Jr, Casalino DD, Francis IR, Jafri SZ, Kawashima A, Kronthal A,
Papanicolaou N, Ramchandani P, Rosenfield AT, Sandler C, Segal AJ,
Tempany C, Resnick MI, Expert Panel on Urologic Imaging. Acute onset of
scrotal pain (without trauma, without antecedent mass). \[online
publication\]. Reston (VA): American College of Radiology (ACR); 2005. 4
p. \[50 references\]

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

### 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)

Acute onset of scrotal pain

#### GUIDELINE CATEGORY

Diagnosis\
Evaluation

#### CLINICAL SPECIALTY

Family Practice\
Internal Medicine\
Nuclear Medicine\
Pediatrics\
Radiation Oncology\
Radiology\
Urology

#### INTENDED USERS

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

#### GUIDELINE OBJECTIVE(S)

To evaluate the appropriateness of radiologic examinations in the
investigation and diagnosis of patients with acute onset of scrotal pain
without trauma, and without antecedent mass

#### TARGET POPULATION

Male adults and children with acute onset of scrotal pain

**Note**: This diagnostic appropriateness discussion is limited to
patients with acute pain who have no history of trauma and no history of
a mass antecedent to the onset of pain.

#### INTERVENTIONS AND PRACTICES CONSIDERED

1.  Ultrasound (US), scrotum

    -   Color and/or power Doppler

    -   Gray-scale only

2.  Nuclear medicine (NUC) scan of the scrotum

    -   Ga-167 or In-111 white blood cell (WBC)

    -   Infection imaging with Ga-67 or In-111 WBC labeling

3.  Magnetic resonance imaging (MRI), scrotum

#### 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

Not stated

#### 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]{.underline}: Acute Onset of Scrotal Pain**

**[Variant]{.underline}: Without trauma, without antecedent mass.**

  -----------------------------------------------------------------------------------
  **Radiologic          **Rating**   **Comments**                      **RRL\***
  Procedure**                                                          
  --------------------- ------------ --------------------------------- --------------
  US scrotum color      9            Excellent study that is generally None
  Doppler and/or power               available and has high            
  Doppler                            sensitivity and specificity.      
                                     Operator and equipment dependent. 
                                     Requires small parts transducer   
                                     with slow-flow-enhancing          
                                     techniques. Must be performed in  
                                     a timely manner. In equivocal     
                                     situations, power Doppler         
                                     evaluation of the spermatic cord  
                                     may be helpful.                   

  NUC, Ga-67 or In-111  7            Well-established study.           Med
  WBC scan, scrotum                  Interpretative experience and     
                                     careful technique required. Must  
                                     be performed in a timely manner.  

  MRI scrotum           3            May be helpful if other tests     None
                                     inconclusive, but must be         
                                     performed in short time frame.    

  US scrotum gray-scale 1            Relatively insensitive to         None
  only                               earliest changes secondary to     
                                     decreased or absent perfusion.    

  NUC infection imaging 1            Infection diagnosis not           High
  with Ga-67 or In-111               obtainable in appropriate time    
  WBC labeling scrotum               frame. Isolated case reports as   
                                     incidental finding.               

  **[Rating                                                            **\*Relative
  Scale]{.underline}:                                                  Radiation
  1=Least appropriate,                                                 Level**
  9=Most appropriate**                                                 
  -----------------------------------------------------------------------------------

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

**[Summary of Literature Review]{.underline}**

The ability to confidently establish a surgical versus a nonsurgical
diagnosis for acute scrotal pain is important. The benefits of early
surgery for testicular salvage in ischemic disease, primarily torsion of
the spermatic cord, are well known but must be balanced against the
costs of operating on the much larger number of patients with
nonsurgical disease, primarily acute epididymitis. Although the acute
scrotum is defined as acute unilateral scrotal swelling, with or without
pain, most patients present with pain as their primary or at least major
concurrent complaint. The differential diagnosis of the acute scrotum
includes: 1) torsion of the testis, 2) torsion of the testicular
appendages, 3) acute epididymitis or epididymoorchitis, 4) mumps
orchitis, 5) strangulated hernia, 6) inflammatory type of testicular
tumor, 7) acute hydrocele, and 8) traumatic hemorrhage. This diagnostic
appropriateness discussion, however, will be limited to patients with
acute pain who have no history of trauma and no history of a mass before
the onset of pain. A minor traumatic episode may call attention to a
scrotal process; and in the adolescent, just becoming aware of his
sexuality may be an enabling event for him to voice his symptoms.

Torsion is decidedly rare in patients older than 35 years. Acute
epididymitis is commonly the cause of acute pain in patients younger
than age 18, very common in patients age 19 to 25, and overwhelmingly
the etiology in patients older than age 25. There are enough exceptions
to these demographics, particularly in patients younger than age 30
years, such that these statistics must be used with caution. In this
group there is also significant overlap in the presence of clinical
factors that may favor torsion (abrupt onset, normal urinalysis) or
epididymitis (more gradual onset, abnormal urinalysis). Acute scrotal
pain in prepubertal boys occurs most commonly from torsion of the
testicular appendages, but may clinically mimic testicular torsion or
epididymo-orchitis. A pathognomic physical examination finding (\"blue
dot sign\") is infrequently encountered.

Radionuclide scrotal imaging (RNSI) is an accurate examination in the
differential diagnosis of ischemia versus infection. The specificity in
the diagnosis of ischemia versus other photon-deficient lesions is
slightly lower. Photon-deficient areas secondary to hydrocele,
spermatocele, uncommonly edematous appendix testis, and rarely an
inguinal hernia can be mistaken for an avascular testis. One study found
that 20 of 27 photopenic scrotal lesions were false positives (not
torsion) and the ultrasound (US) examination prevented unnecessary
surgery in 16 (59%) of these cases. There have been many large series
reported. The examination and the technique are well established and
reproducible, and most imaging specialists and nuclear medicine
technologists have been trained in the performance and interpretation of
these examinations. With scintigraphy, some problems arise in infants
and very small children whose genitalia are small and therefore
difficult to image. Because this examination is performed relatively
infrequently in many departments, the experience of individual
practitioners may be limited. With increasing use of sonography,
experience with RNSI, especially for more recently trained physicians,
is decreasing. Availability and time of examination can also be limiting
factors.

The imaging of infected scrotal contents, testis, or epididymitis with
the radionuclide infection imaging agents Ga-67 or In-111 WBC has been
noted in isolated case reports. There is, however, no routine indication
for their use.

Color Doppler ultrasound (CDU) is also a valuable exam for evaluating
testicular perfusion. Studies in the early 1990s showed a reasonable
sensitivity and specificity for diagnosis of torsion comparable to RNSI.
The CDU equipment has improved, and experience has increased, with
resultant sensitivity and specificity now ranging from approximately
89%-100%. Experience with CDU in evaluating the acute scrotum has
increased, both for practicing physicians and for those in training. It
is readily available at most, if not all, institutions and can be done
quickly without any specific preparations. Power Doppler (US) can be
used in place of, or as an adjunct to, CDU. Power Doppler has been shown
to demonstrate flow where CDU does not and, in general, to demonstrate
slower flow than CDU. Power Doppler US is especially useful to
demonstrate intratesticular flow in prepubertal testes.

Doppler US is not without drawbacks, and one area of concern has been
its application in the young child and particularly the prepubertal
child. Studies in children have shown a sensitivity of 89% and
specificity of 100%, but there were technically unsuccessful studies
which emphasize the need for experience and proper equipment settings
when examining the young child. Settings optimized to detect slow flow
include a small color-sampling box, lowest pulse repetition frequency,
and lowest possible threshold setting. Blood flow can occasionally be
preserved in patients with torsion. Attention to spectral Doppler
waveforms patterns (high-resistance arterial waveform, monophasic
waveform) and spermatic cord morphology (thick spermatic cord) may help
diminish false negative examinations. A multicenter study of 919
patients aged 1-18 years studied for an acute scrotum found false
negative CDU studies in 50 of 208 patients with torsion (sensitivity
76%). An abnormal spermatic cord \"twist\" was identified, however, in
199 of 208 patients (sensitivity 96%). Further, a normal linear cord
(705/711, 99% specificity) was found in patients without torsion.

In a comparison of 294 patients with primary scrotal exploration and 332
with US first and exploration if US was positive or there was a high
clinical suspicion of torsion, one study found that US could obviate the
need for exploration in many patients, and thus minimized and shortened
hospital stays.

Gray-scale US alone is capable of evaluating the cystic or solid nature
of scrotal masses and often the signs of an inflamed epididymitis and a
necrotic testicle, but it is much less sensitive to the earliest changes
resulting from decreased or absent testicular perfusion. In the setting
of torsion, a normal homogenous echo pattern is, however, likely to
indicate a viable testis, whereas a hypoechoic or inhomogeneous testis
is likely to be nonviable.

The most common cause of acute scrotal pain in adolescent boys and
adults is epididymoorchitis. Grayscale US combined with color Doppler
imaging is the prime imaging means to make this diagnosis. The
epididymis is enlarged and may be increased or decreased in
echogenicity. Scrotal wall thickening and hydrocele are common. The
testis is involved in 20%-40% of cases (epididymo-orchitis). Increased
color Doppler flow in the epididymis and, if involved, the testis, is
characteristic. The most common cause of acute scrotal pain in the child
is torsion of a testicular appendage (appendix epididymis or appendix
testis). Reactive changes (hydrocele, epididymal head enlargement,
increased color Doppler flow) from torsion of a testicular appendage may
mimic epididymitis. The torsed testicular appendage can be difficult to
identify with US. It was seen in only 9 of 29 patients (31%) in one
study, but it is usually larger, rounder, and has more surrounding flow
than normal appendages. Size alone may discriminate torsed from normal
testicular appendages with low sensitivity (67%) but high specificity
(100%), obviating surgery in some cases.

Magnetic resonance imaging (MRI) techniques has been rarely used in
diagnosing the acute scrotum, although reports of its use in scrotal
disease are increasing. In one report, 11 patients with subacute signs
and symptoms were evaluated, and a differential diagnosis between
ischemia in six patients and infection in five patients could be made.
In a second study of 39 patients with an acute scrotum and an
inconclusive US and physical exam, MRI had a sensitivity of 93% and a
specificity of 100% for torsion. Experimental studies also suggest
potential use of MRI in acute torsion. Another study suggests that MRI
may be useful to identify patients with segmental testicular infarction
when US is not conclusive.

**Summary**

Both CDU and RSNI are valuable techniques for determining the etiology
of acute scrotal pain. Although some authors still suggest immediate
surgical exploration in patients with a strong clinical impression of
testicular ischemia, if either CDU or RNSI is readily available and can
be performed within 30--60 minutes of the request to simultaneously
prepare an operating room, there is ample evidence that fewer patients
with infection will be operated on, and also that patients with an
ischemic testis will not be treated with antibiotics for infection. The
choice of CDU or RNSI should be based on availability and operator
experience. In most institutions, availability and experience will favor
CDU. If one performs CDU and there remains a question about a diagnosis,
US evaluation of the spermatic cord, MRI, or RNSI may be of value.

**Abbreviations**

-   MRI, magnetic resonance imaging

-   NUC, nuclear medicine

-   US, ultrasound

-   WBC, white blood cell

#### CLINICAL ALGORITHM(S)

None provided

### 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 the
investigation and diagnosis of patients with acute scrotal pain

#### POTENTIAL HARMS

-   With scintigraphy, some problems arise in infants and very small
    children whose genitalia are small and therefore difficult to image.
    Photon-deficient areas secondary to hydrocele, spermatocele,
    uncommonly edematous appendix testis, and rarely an inguinal hernia
    can be mistaken on radionuclide scrotal imaging for an avascular
    testis. Because this examination is performed relatively
    infrequently in many departments, the experience of individual
    practitioners may be limited. With increasing use of sonography,
    experience with radionuclide scrotal imaging (RNSI), especially for
    more recently trained physicians, is decreasing. Availability and
    time of examination can also be limiting factors.

-   The relative radiation level is high with nuclear medicine (NUC)
    infection imaging with Ga-67 or In-111 white blood cell (WBC)
    labeling and medium with NUC Ga-67 or In-111 WBC scan of the
    scrotum.

### 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)

Remer EM, Francis IR, Baumgarten DA, Bluth EI, Bush WH Jr, Casalino DD,
Curry NS, Israel GMN, Jafri SZ, Kawashima A, Papanicolaou N, Sandler CM,
Spring DB, Fulgham P, Expert Panel on Urologic imaging. Acute onset of
scrotal pain-without trauma, without antecedent mass. \[online
publication\]. Reston (VA): American College of Radiology (ACR); 2007. 5
p.

#### ADAPTATION

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

#### DATE RELEASED

1995 (revised 2007)

#### 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 Urologic Imaging

#### COMPOSITION OF GROUP THAT AUTHORED THE GUIDELINE

*Panel Members*: Erick M. Remer, MD; Isaac R. Francis, MD; Deborah A.
Baumgarten, MD; Edward I. Bluth, MD; William H. Bush, Jr., MD; David D.
Casalino, MD; Nancy S. Curry, MD; Gary M. Israel, MD; S. Zafar H. Jafri,
MD; Akira Kawashima, MD; Nicholas Papanicolaou, MD; Carl M. Sandler, MD;
David B. Spring, MD; Pat Fulgham, MD

#### FINANCIAL DISCLOSURES/CONFLICTS OF INTEREST

Not stated

#### GUIDELINE STATUS

This is the current release of the guideline.

It updates a previous published version: Older RA, Choyke PL, Bluth EI,
Bush WH Jr, Casalino DD, Francis IR, Jafri SZ, Kawashima A, Kronthal A,
Papanicolaou N, Ramchandani P, Rosenfield AT, Sandler C, Segal AJ,
Tempany C, Resnick MI, Expert Panel on Urologic Imaging. Acute onset of
scrotal pain (without trauma, without antecedent mass). \[online
publication\]. Reston (VA): American College of Radiology (ACR); 2005. 4
p. \[50 references\]

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 in Portable Document Format (PDF) from the
[American College of Radiology (ACR) Web
site](http://www.acr.org/SecondaryMainMenuCategories/quality_safety/app_criteria/pdf/ExpertPanelonUrologicImaging/AcuteOnsetofScrotalPainWithoutTraumaWithoutAntecedentMassDoc2.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 are 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.aspx).

-   ACR Appropriateness Criteria®. Relative radiation level information.
    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/RRLInformation.aspx).

#### PATIENT RESOURCES

None available

#### NGC STATUS

This summary was completed by ECRI on May 6, 2001. The information was
verified by the guideline developer on June 29, 2001. This summary was
updated by ECRI on September 8, 2004. The updated information was
verified by the guideline developer on October 8, 2004. This summary was
updated by ECRI on February 8, 2006. This NGC summary was updated by
ECRI Institute on November 14, 2007.

#### 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

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Date Modified: 11/3/2008